Collaborative Visualization in Earth · images onto wall-sized cylindrical screens (Figure 1). These systems allow users to combine and explore data and images in innovative ways

New

slett

er N

o. 8

, Sp

rin

g 2

00

2

In This Issue:

Published bi-annually by the

MARGINS OfficeLamont-Doherty Earth Observatory

of Columbia University

61 Route 9W, P.O. Box 1000

Palisades, NY 10964-8000

USA

Science Article

Collaborative Visualization

Central America update

Editorial

MARGINS funding, organization

Workshop reports

Community Sediment Model

Nankai SEIZE Town Meeting

Central America Town Meeting

Borderlands Workshop

News & Announcements

MARGINS-NSF post-doc

Funded MARGINS Programs 2002

Steering Committee Highlights

Office Update Publication Number, Logo Use

Contact Information

......................1-2

...........................3-5

............6-7

....................8-9

......................10

................12

................................12

................................13

......14-16

....................17

...................18

...........................19

Is your PowerPoint presentation a bit flat?Worse yet, has your latest image of Earthstructure left your audience adrift? In-creasingly, the near exponential growthin the number and size of datasets overthe past decade has placed an unfair bur-den on the geoscientist to integrate dis-parate data streams seamlessly into a co-herent picture. The number-crunchingaspects of these problems can be over-come through access to the latest super-computers, but typically only a few in-vestigators can interact with these smallscreen images at any one time, limitingtheir usefulness. To overcome this, newvisualization technologies have been de-veloped to immerse users into a virtualworld by projecting three-dimensionalimages onto wall-sized cylindricalscreens (Figure 1). These systems allowusers to combine and explore data andimages in innovative ways and are greatly

enhancing scientists’ ability to visualize,understand and collaborate on complexdatasets.

On March 4th, 2002, Scripps Institu-tion of Oceanography (SIO), San DiegoState University (SDSU), and the Cali-fornia Institute for Telecommunicationsand Information Technology (Cal-(IT)2)along with four California-based compa-nies unveiled the world’s first visualiza-tion complex dedicated to the Earth andOcean Sciences. Linked by a 2.4 giga-bit-per-second optical network, SIO’s Vi-sualization Center and SDSU’s Center forImmersive Telecommunications for Glo-bal Exchange will empower scientists tocollaborate in real-time on large 3-Ddatasets. Using the networked SIO/SDSUvisualization centers, groups of research-ers at both institutions are able to sendand receive data and images simulta-neously, and collaborate on analyzing:

Collaborative Visualization in Earth

and Ocean SciencesGraham M. Kent1, Deborah L. Kilb1, John A. Orcutt1, and Eric G. Frost2

1. Cecil H. and Ida M. Green Institute of Geophysics and Planetary Physics, Scripps Institution of Oceanography,San Diego, CA 92124, USA

2. Department of Geological Sciences, San Diego State University, San Diego, CA 92182-1020, USA

Figure 1. View of the Panoram® cylindrical screen (8’6"x28’4") and three Digital Christie®projectors. Bathymetry of the 9°03’N overlapping spreading center at the EastPacific Rise is displayed using Interactive Visualization Systems’ Fledermaus, whichenables disparate data types to be simultaneously displayed (e.g. bathymetry, seismicprofiles, seafloor imagery, fault scarps, and earthquakes locations to name a few)

Page 2 MARGINS Newsletter No. 8, Spring 2002

• Real-time seismic and climate dataalong the high-tech California coast-line

• Earth structure, including its oceansand atmosphere

• Impact of global warming on Earth’sclimate

• Fault-related deformation and itscorrelation with earthquake loca-tions

• Structure and dynamics of coastlines• Real-time hazard analyses to assist

emergency response teams• Detailed planetary topography (e.g.

Mars)The Visualization Center at Scripps

(http://siovizcenter.ucsd.edu) is builtaround a Panoram® GVR-120E curvedfloor-to-ceiling screen (8’6"x28’4") fea-turing 3.2 megapixel resolution (3,276,800 pixels). This immersive environmentis ideal for groups of up to 60 people whocan view these large-format images at thesame time. The system is equipped withtransmitters and LCD shutter glasses(Figure 2) which permit stereographic 3-D viewing of high-resolution images. Thethree projectors use advanced technologyto automatically blend the edges wheretheir video outputs meet. The InfiniteReality graphics subsystem is driven bya single-pipe SGI® Onyx® 3400 with a

system bandwidth of 44 GBps. TheOnyx® is powered by16 MIPS® R12Kprocessors and 16 GB of addressablememory. The Panoram® visualizationsystem enables simultaneous display ofvideo and audio streams; video and au-dio sources include the SGI® megadesk-top and stereo megadesktop, S-VHSvideo, DVD video, and video from aMacintosh® or PC.

For instance, one-third of the screenmight be displaying S-VHS video froma remotely-operated-vehicle (ROV),while the remaining portion of the screencan be used for an interactive 3-D flightover same parcel of seafloor. The videoand audio combinations using this sys-tem are numerous! The two centers arelinked via Cox® Communications’ 44-mile, 2.4 gigabit-per-second optical-fibernetwork. Networking of the two visual-ization centers is facilitated by TeraBurstNetworks’ WAVS® (Wide Area Visual-ization Solution), based on a high-per-formance, optical networking platform(OC-48) to enable transmission of mas-sive amounts of data between multiplelocations. This is the only technologyavailable that enables video, audio, anddata to be transmitted simultaneouslyover a wide-area optical network to geo-graphically distributed centers.

These two centers for visualizationhave already had a great impact on ourEarth and Ocean Sciences community.Future collaborations at the center arelikely to include, to name but a few,strategizing ships tracks for experiments,location of instruments at IntegratedStudy Sites (RIDGE 2K) or within Fo-cus Sites (MARGINS), and selection ofIODP drill-sites. Visualization softwarepackages now available include: Inter-active Visualization Systems’ Fledermausand Data Magic; Paradigm Geophysical’sFocus 3-D, VoxelGeo and GeoDepth 3-D; IBM Data Explorer’s, OpenDX;NCAR’s Vis5D; ESRI’s ArcView andArcInfo; and Mathwork’s MATLAB.

Graham Kent is Director of the Scripps Vi-sualization Center; Debi Kilb is Science Di-rector of the center; John Orcutt is Directorof the Cecil H. and Ida M. Green Institute ofGeophysics and Planetary Physics; EricFrost is Director of the Center for ImmersiveTelecommunications for Global Exchange. Tocheck on availability and to schedule the fa-cility, please contact Kitty Haak, (e-mail:[email protected], phone: (858) 534-0229).

Science Article

Figure 2. View of the Los Angeles Basin in stereo 3-D, highlighting SRTM topography, fault-lines, and earthquake locations.

MARGINS Newsletter No. 8, Spring 2002 Page 3Science Article

In May and June 2000, a cruise with theR/V Ewing acquired a variety of geophysi-cal data along the Pacific margins of Nica-ragua and northernmost Costa Rica in sup-port of the MARGINS Central Americafocused research. This was chosen as afocus area for both the Seismogenic Zoneand Subduction Factory initiatives in partdue to the variations in seismogenic andgeochemical characteristics from Nicara-gua through Costa Rica, which could becompared and contrasted along a contigu-ous convergent margin with a commonsubducting plate.

At the time of our cruise, extensivemarine geophysical data had been ac-quired along the Middle America trenchand forearc offshore Costa Rica, but MCSdata offshore Nicaragua were largely lim-ited to petroleum industry seismic pro-files spanning the broad continental shelfand a single, ‘70s-vintage MCS profile(UTIG NIC-1) crossing the forearc andtrench. In the ‘90s investigators fromGEOMAR, Kiel, Germany acquired sev-eral wide-angle seismic profiles, in-cluding an onshore/offshore dip transectalong NIC-1, and an area of swath bathy-metry covering much of the trench and ablock of the slope off Nicaragua. Withthe motivation to identify causes of theobserved variability throughout the fo-cus area, it became clear that new MCSdata were desperately needed offshoreNicaragua as well as contiguous swathbathymetry coverage.

Our survey focused on seismic data ac-quisition, and we acquired more than 2800km of 240 channel MCS data and ~580km of wide-angle seismic data (Figure 1).The wide-angle data were recorded byocean bottom hydrophone instruments(OBHs), supplied and operated by col-laborating researchers from GEOMAR,and by land instruments supplied byPASSCAL and ETH (Zurich, Switzerland)operated by participants from University

of Texas Institute for Geophysics (UTIG),ETH, and INETER (Managua, Nica-ragua). The wide-angle data set includes16+ successful land deployments on twoonshore/offshore transects and 39 success-ful OBH deployments on these twotransects and a marine-only strike profile.In addition to acquiring the seismic data,we expanded the swath bathymetry map-ping to achieve essentially contiguouscoverage in the trench and slope areas

from Costa Rica to Nicaragua, and wemapped areas significantly farther north-west along the trench. We also added im-portant gravity and magnetic coverageacross the shelf and trench slope.

At this time (April 2002), convention-al (MCS) seismic processing is largelycomplete, and we have started using pre-stack (time and depth) imaging tech-niques to improve the reflection imagesand provide true geometry at shallow to

-89˚ -88˚ -87˚ -86˚ -85˚

9˚

10˚

11˚

12˚

13˚

14˚

0 100 200

km

-4000

-4000

-2000

NICARAGUA

COSTA RICA

Nicoya Peninsula

HONDURASEL SALVADOR

volcanic arc

NIC-1

0

NIC-1

4

NIC-2

0NIC

-30

NIC-4

0

NIC-5

0NIC-6

0NIC-7

0

NIC-8

0

NIC-9

0NIC-1

00

NIC

-110

NIC-115

NIC-125

-89˚ -88˚ -87˚ -86˚ -85˚

9˚

10˚

11˚

12˚

13˚

14˚

Figure 1. Map showing location of our survey. Includes bathymetric contours, line locations,OBH and land instrument locations, and position of the Central America volcanic arc.

Nicaragua/Costa Rica Marine Geophysics UpdateKirk McIntosh1, Imtiaz Ahmed1, Eli Silver2, Robyn Kelly3, Cesar R. Ranero4, Ernst Flueh4, and Arnim Berhorst4

1. University of Texas at Austin, Institute for Geophysics, Austin, TX 78759-8500, USA2. Earth Sciences Department, University of California, Santa Cruz, Santa Cruz, CA 95064-1077, USA

3. Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA4. GEOMAR, Wischhofstraße 1-3, 24148 Kiel, Germany


intermediate depths. We have also devel-oped preliminary velocity models usingthe wide-angle data sets, which providea crustal scale perspective of the margin.In the following sections we briefly de-scribe some of the preliminary results ofthe project. Our objective is to share ourpreliminary results with the MARGINScommunity, indicate where we areheaded with our research, and stimulatefuture research, which may be aided bythis data set and our results.

Deep StructureIn general, the seismic data exceeded ourexpectations in depth of reflection pen-etration and in offset distance of inter-pretable wide-angle data. On most reflec-tion profiles we image the Cocos/Carib-bean plate boundary to depths of at least20 km and in some cases to greater than40 km. This means that on at least thesix longest profiles we probably imagethe plate boundary throughout the limitsof seismogenic rupture. In addition, someprofiles (Figure 2) feature prominentdeep reflections above the plate bound-ary that probably mark the base of theupper plate crust. Our preliminary wide-

angle velocity analysis supports this inter-pretation, but it has not yet been rigor-ously confirmed. Ultimately, by know-ing the accurate positions of the plateboundary and upper plate Moho, we in-tend to examine whether the down-diplimit of the interplate seismogenic zonecoincides with the intersection of theseboundaries as postulated (e.g., one of thecontrolling factors indicated by Oleske-vich et al., 1999 — the other being tem-perature).

Cocos Plate/Lower Slope StructureAmong the primary objectives of ourproject is to examine the structuraldevelopment of the Cocos Plate as itbends into the Middle America trench,and the effects these lower plate struc-tures have on sediment subduction andon deformation of the upper plate. To thisend, we filled in many gaps and extendedthe swath bathymetric coverage previ-ously obtained by GEOMAR. Two of theinteresting observations that were sug-gested by the GEOMAR data set and con-firmed with the expanded data set andseismic profiles are that there is a sub-stantial increase in the number of sea-

mounts from offshore Northern CostaRica to Nicaragua and that the faultingrelated to plate bending is almost exclu-sively down to the trench. This fault pat-tern leads to distinctive half-graben for-mation with blocks frequently rotatedback ~5° (i.e. away from the trench) de-

8400

8400

7200

7200

6000

6000

4800

4800

3600

3600

2400

2400

1200

1200

0.0 0.0

1.0 1.0

2.0 2.0

3.0 3.0

4.0 4.0

5.0 5.0

6.0 6.0

7.0 7.0

8.0 8.0

9.0 9.0

10.0 10.0

11.0 11.0

12.0 12.0

13.0 13.0

NIC40 FX Migration

Plate Boundary

Moho?

15 kmSW NE

(vertical scale: time in seconds)

Middle America Trench

Costa RicaNicaragua100

80

60

40

20

0550 650 750 850 950 1050

Along Strike Distance (km)

Change in RMS Height of BathymetryAlong Strike of Trench

RM

S H

eig

ht

(m)

0-25

km

fro

m T

ren

ch

Figure 2. Landward portion of line NIC-40 showing deep reflections marking the Cocos/Caribbean plate boundary and possible base ofupper plate crust (Moho).

Figure 3. RMS height variation of Cocos platebathymetry along the Middle AmericaTrench from Nicaragua to northernCosta Rica. This figure demonstratesa clear peak in the magnitude of fault-related bathymetric offsets off centralNicaragua and a precipitous decreaseinto the area off Costa Rica.

MARGINS Newsletter No. 8, Spring 2002 Page 5Science Article

spite the overall bending into the trench,which has a relief of > 2 km and an aver-age seafloor dip near 5° into the trenchaxis off central Nicaragua. We are per-forming statistical analyses of the bathy-metric data using an automated computercode, which characterizes the orientationand magnitude of bathymetric features.This work, with calibration from theMCS data, documents that the throw onthe trenchward dipping normal faults onthe Cocos Plate decreases dramaticallyalong strike from central Nicaragua to thetrench off the central Nicoya Peninsula(Figure 3). It is possibly significant thatthis pattern is quite similar to the patternof geochemical sediment subduction trac-ers directly landward along the CentralAmerica volcanic arc. At this point wecan speculate that the fault structure ofthe Cocos plate leads to very efficientsediment subduction beneath centralNicaragua, but we are working to morerigorously establish whether this is morethan an apparent relationship.

One of the related tasks of examiningthe variability of sediment subduction is tocreate the best possible images of the sub-ducting half-grabens with the MCS data.This is a particularly difficult problem dueto relatively high-velocity material (3-4 km/s) in the upper plate that extends essentiallyto the trench, creating a velocity inversionas it overrides the subducting sedimentarysection. We have started to depth-migratethe MCS data before stack to compensatefor these imaging problems. One of our firstresults using prestack depth imaging isshown in Figure 4. Although the image de-teriorates with depth due to loss of high fre-quencies, we can see that the half-grabenstructures are subducted intact beneath thelower slope, and there is no indication inthe image or the derived velocity model thatsignificant sediment has been accreted tothe upper plate. On the contrary, there isstrong evidence throughout the data set thatthe half-graben structures, with surfacescarps to at least 500 m, and the numeroussubducting seamounts seriously deform themargin wedge below the trench slope, lead-ing to partial collapse and probable tectonicerosion.

Sandino Forearc BasinThe Sandino forearc basin underlies

the shelf offshore the full length of Nica-ragua. The basin’s sedimentary thicknessvaries from ~4-5 km at the southeasternend of our survey area to an incredible~15 km at the northwestern end. Near thecoast, and extending onshore, the basinsedimentary section is deformed in com-pressional and/or transpressional struc-tures along a 10-30 km wide (in the off-shore), coast-parallel swath. In contrast,in the seaward portion of the basin, andcontinuing to the trench slope, the defor-mation is extensional with both seawardand landward dipping normal faults com-mon. One of the significant observationsthat we have been able to make on someMCS profiles across the Sandino Basinis that clinoforms, indicative of paleo-shelf edge positions, seem to have kept arelatively stable position, compared to thecurrent coastline, since ~ Middle Mi-ocene (age based on the seismic units ofRanero et al., 2000). Continued slow sub-sidence, probably due to a combinationof factors including subduction erosion,trench rollback, and/or gradually steeper

3200

3200

3500

3500

3800

3800

4100

4100

4400

4400

4 4

5 5

6 6

7 7

NIC30 Prestack Depth Migration

Dep

th (

km)

5 km

Middle America Trench

fault blocks

detachment

Figure 4. Seismic image of line NIC30 across the trench and lower slope produced by prestackdepth migration. This image illustrates the back-rotated fault blocks as they enter thetrench and shows that they remain intact as they are thrust beneath the lower slope.

ReferencesOleskevich, D. A., R. D. Hyndman, and K. Wang, The updip and downdip limits to great subduction

earthquakes: Thermal and structural models of Cascadia, South Alaska, SW Japan, andChile, J. Geop. Res., 104, 14965-14991, 1999.

Ranero, C. R., R. von Huene, E. R. Flueh, M. Duarte, D. Baca, and K. McIntosh, A cross section of theconvergent Pacific margin of Nicaragua, Tectonics, 19, 335-357, 2000.

von Huene, R., C. R. Ranero, W. Weinrebe, and K. Hinz, Quaternary convergent margin tectonics ofCosta Rica, segmentation of the Cocos Plate, and Central American volcanism, Tectonics,19, 314-334, 2000.

slab position, has allowed preservationof these strata and suggests that radicalchanges in the trench-forearc systemhave not occurred over this time. Thiswill be a particularly important area foradditional study and for comparison withsome of the Costa Rican segments of themargin where subduction erosion isdocumented (von Huene et al., 2000).

Future PlansWe plan to continue working in the areasdescribed here, focusing on deep reflec-tions, structure of the Cocos Plate and itspossible influence on sediment subduc-tion, and imaging the lower slope. Weplan also to improve our images in thedeformed parts of the Sandino basin andour seismic stratigraphic interpretationacross the basin to better document thetectonic development of the region. Ul-timately, we will identify and study thekey differences and similarities along thelength of the Costa Rica/Nicaragua con-vergent margin.

Page 6 MARGINS Newsletter No. 8, Spring 2002 Editorial

From the Chairman’s Desk: Spring 2002Garry D. Karner

Lamont-Doherty Earth Observatory, 61 Route 9W, Palisades, New York 10964, USA

The MARGINS Program continues togrow and has become a viable force inthe Earth Science community. The num-ber of funded projects continues to growand the more advanced initiatives (SEIZEand SubFac) are in the process of creat-ing proposals for IODP riser drilling (e.g.Nankai and Osa peninsula). During 2001-2002, Source-to-Sink joined the otherinitiatives with the funding of researchin the New Guinea focus site.

The MARGINS Office has been andremains very busy in assisting principalinvestigators in setting up the budgets forworkshops and theoretical institutes inaddition to organizing AGU town meet-ings and pending workshops (e.g. theIBM workshop in Hawaii). Significanteffort has also been ex-pended on working withSaudi and Egyptian organi-zations to prepare onshoreand offshore proposals forthe RCL Gulf of Suez/north-ern Red Sea focus site. Thediplomatic and logistic chal-lenge of working in the Gulfof Suez/northern Red Sea re-gion is significant but pro-gress is being made. Presenting the themeand objectives of the U.S. MARGINSProgram at Middle Eastern geologicalmeetings (e.g. Bahrain in April and theCairo AAPG meeting in October) has andshould help tremendously.

Budget issuesThe 2001-2002 MARGINS fiscal yearhas seen the establishment of a datapolicy and a fellowship scheme. Dead-lines for fellowship applications are thesame as the MARGINS proposal dead-line, 1 November in each year.

In terms of the MARGINS budget, atroubling trend is that, even given the con-tinuing successes of the MARGINS Pro-gram involving both NSF-EAR and NSF-OCE/ODP communities, the low level offinancial support for MARGINS is

disproportionate to the program’s grow-ing importance, national and internationalimage, and success. Equal fiscal partici-pation by all three NSF divisions is abso-lutely critical to the success of the MAR-GINS Program with the present internalfunding arrangement beginning to com-promise the ability of the program to workeffectively. It is thus hoped that NSF willsee its way to increase significantly theMARGINS budget in the next (and sub-sequent) fiscal year(s).

As can seen from the table below, therate of funding is at a standstill and sig-nificantly below original expectations.

The present funding level is parti-cularly disappointing, especially as the in-ternational phase of MARGINS negotia-

tions is at a sensitive and crucial stage inproject planning and ship operation, andfacility costs related to field programs areabsorbing precious research funds. If theMARGINS Program has any hope ofachieving the fundamental objectives out-lined through a host of community work-shops and as summarized in the variousscience plans, there needs to be a markedincrease in the MARGINS budget.

Organization of MARGINSThe MARGINS Office routinely fieldsquestions about Steering Committeemembership and possible conflicts of in-terest between Steering Committee mem-bers, the NSF-MARGINS Panel and thefunding of proposals. Perhaps it is timelyto discuss these issues and provide feed-back to the community (Figure 1):

THE NSF-MARGINS REVIEW PANEL

comprises 6 individuals, on average, andthe membership changes dramatically foreach session. Because of an obvious con-flict of interest, absolutely no memberof the MARGINS Steering Committee(including the chair) is allowed to sit onthe Panel or even knows the composi-tion of the Panel (until the steering com-mittee meeting months later).

Following the NSF-MARGINS pro-posal deadline on the 1 November, thePanel convenes in February for its delib-erations. The date of the Spring MAR-GINS Steering Committee meeting is se-lected only after proponents have been in-formed about the status of their proposal.Thus, no feedback can occur between the

recommendations of thePanel and the deliberationsof the MARGINS SteeringCommittee.

The objectives of theSpring steering committeemeeting are to review,with the program manag-ers, the direction/balanceof the program followingthe last round of success-

ful funding and to recognize if criticalareas are being neglected and why.Sometimes also, a proposal that is criti-cal to MARGINS falls through the cracksand the committee is in a position to helpidentify such proposals.

Finally, it should always be remem-bered that active researchers working onthe cutting-edge of MARGINS problemswill likely serve, at some time, on thesteering committee. Their research doesnot cease because of their committeemembership and thus it should be no sur-prise that members on the committeemay also successfully field NSF-MAR-GINS proposals.

The timing of the Fall Steering Com-mittee meeting is selected in order to helpwith the planning of AGU town meet-ings and special sessions.

FY98 FY99 FY00 FY01 FY02 Award Award Award Award Award

MARGINS 250,197 2,856,521 2,877,373 5,603,987 4,133,038*margins 2,806,185 1,802,176 2,771,639 2,126,256 499,339

Total 3,056,382 4,658,697 5,649,012 7,730,243 4,632,377

Table 1. MARGINS Budget numbers for the fiscal years 1998-2002.”MARGINS” are proposals reviewed by an NSF-MARGINS panel,whereas ”*margins” represents funding of margins-relatedprojects independent of the MARGINS Panel.

MARGINS Newsletter No. 8, Spring 2002 Page 7

National ScienceFoundation

MARGINS Office

MARGINS Steering Committee

NSF-MARGINS Panel

T h e E a r t h S c i e n c e C o m m u n i t y

THE MARGINS STEERING COMMITTEE

comprises 15 members who serve a threeyear term, on average. The committeemeets twice a year (Spring and Fall) andtheir work involves the preparation of whitepapers and workshop proposals, review theprogress of the program according to thevarious science plans and feedback fromprogram managers, help promote theMARGINS program in the scientific com-munity, and provide advice and feedbackto NSF program managers and the MAR-GINS chair concerning issues and problemsthat arise during the execution of the pro-gram. Each steering committee memberis expected to work actively to promoteMARGINS in their respective communityby recognizing the need for, and theme of

workshops and/or theoretical institutes, andto work with their community to preparethe necessary proposals.

Every semester, two people rotate offthe committee. Nomination to the com-mittee is either via self nomination, ornominations from the community follow-ing a “Call for Nominations” distributedevery six months by the MARGINS Of-fice, or via recommendations made by re-tiring committee members. MARGINShas long adopted a policy with respect tocommittee membership in order for thecommittee to remain balanced, dynamicand unbiased: 1) once a person has servedon the steering committee, they cannotre-serve (unless they are being consid-

ered for the steering committee chair),and 2) there cannot be institutional du-plication by committee members. Exper-tise on the committee is arranged to coverthe generalities of each of the initiativesand focus sites, if at all possible.

I would like to take this opportunityto thank the following members, whoseterms finished in either Fall 2001 orSpring 2002, for their unselfish contri-bution of time and effort to the steeringcommittee and the Earth Science com-munity: Susan Debari, William Dietrich,Simon Klemperer, Chuck Nittrouer, andBrian Taylor. Susan provided the com-mittee valuable advice regarding out-reach and education issues while Bill andChuck invested a huge effort in organiz-

ing the many Source-to-Sink workshops,town meetings and the preparation ofseemingly endless Science Plan and Ex-ecutive Summary drafts and rewrites.Simon is thanked for his help and effec-tiveness in rewriting the MARGINS datapolicy and fellowship statements. Brian’scontribution is profound given his piv-otal role in rescuing the MARGINS Pro-gram five years ago and aggressively se-curing a funding base from NSF. Allmembers are thanked for their soundjudgment and advice during the delibe-ration of a range of committee and com-munity issues.

In turn, I welcome the following newmembers onto the steering committee:

Scott Linneman, Anne Meltzer, JohnMilliman, Rudy Slingerland and PatriciaWiberg. Scott brings to the committeeexpertise and knowledge concerning edu-cation and outreach issues. AnneMeltzer, through her ties with theEarthscope community, brings a majorperspective from the IRIS and Earthscopeprograms at a time when liaisons withthese groups are particularly important.Likewise, Pat, John and Rudy, whose col-lective expertise ranges across storm-driven transport and the formation ofsedimentary strata on the continentalshelf, the long-term generation of thestratigraphic record, carbonate de-positions systems, quantitative terrestrialgeomorphology and sedimentology, arein the position to provide valuable in-sights into enacting the objectives of theSource-to-Sink initiative.

Finally, I feel it is important to remindMARGINS researchers interested in sub-mitting proposals for work in NewGuinea, New Zealand, Mexico and thenorthern Red Sea that it is crucial to in-volve local collaborators, researchersand/or students, in the proposal process.In fact, foreign collaboration is a pre-requisite for MARGINS funding in for-eign focus sites. While NSF does not di-rectly provide for the salaries or travelcosts of foreign collaborators, it does soin case of ”unique expertise or other cir-cumstances where research support cannot be provided by any other means” (i.e.the U.S.-supported research effort can-not be accomplished otherwise). It is sug-gested that principal investigators includesufficient funds in their proposals to helpfund participation by foreign researchersand students in fieldwork, short-term re-search visits (3-6 months), and tuitionfees for foreign students to attend U.S.universities.

Figure 1. The components of the MARGINS Program and their interrelationships. The EarthScience Community is the fundament of MARGINS. The review panel is selected bythe NSF within the community. The Office functions as a point of contact, organizer,and general information center.


Quantitative modeling of the dynamicsof the Earth’s surface has been going onin various forms for many decades. En-gineers, faced with management prob-lems involving waterways and coastlines,have traditionally led the quantitativeapproach; other communities, mainly inthe Earth sciences, have come later tomodeling and focused more on naturalprocesses and longer time and spacescales. Up to now, however, the variousgroups have carried out their work onspecific problems in relative isolation.

On February 20-22, 2002, some 60researchers representing fields as diverseas glaciology, sedimentary geology, geo-morphology, engineering, and geo-physics met to launch what we hope willbe a new era in quantitative modeling ofthe Earth’s surface. The workshop wasfunded by the National Science Founda-tion with financial support from bothmarine and terrestrial geoscience divi-sions. The forum was a workshop cen-tered on a new initiative called the Com-munity Sediment Model (CSM), whichaims to unite the scattered efforts of thesevarious researchers and research commu-nities in a common framework with acommon set of support tools. The ex-pected products for the CSM are (1) aset of flexible, modular modeling toolsand protocols, developed by the com-munity, that would be combined to sup-port a wide variety of model approaches,goals, and time and space scales; and (2)a set of sophisticated “stand-alone” mod-els created from these modular compo-nents for application in predicting surfaceprocesses. These models would supportstudies of basic science questions relatedto Earth surface dynamics as well as workon applied problems including river andcoastal zone management, assessment ofrisk from natural hazards, and resourceexploration and development. The CSMworkshop goal was to produce the blue-print for this effort.

The meeting began with a vision ofa “sedimentary modeling environment”comprising a highly flexible suite ofcommunity-based software modulesaimed at calculating surface fluxes andevolution as well as pre and post pro-cessing of the results. Next came a setof talks about the nuts and bolts of whatit’s like to actually put together some-thing like this by representatives fromseveral research communities with rel-evant experience, including atmo-spheric science, glaciology, oceanogra-phy and hydrology. We heard about theirexperiences, in some cases spanningmore than two decades, including in-dispensable information about organi-zation, code structure, management, andsociology — all things the sed-strat-

geomorph community will have to learnabout if our effort is to succeed. In ad-dition to the distilled wisdom of ourmore experienced colleagues, we wereheartened to learn about efforts such asthe NCAR Earth System ModelingFramework, which may provide tem-plates and specifications that we can useto get started quickly and improveinteroperability with other modelingprograms. We also heard about the di-versity of modeling approaches alreadyin use for surface processes, rangingfrom classical differential equationbased methods to cellular models andhybrids of various kinds.

The following day was spent sum-ming up the state of modeling in vari-ous branches of what we may begin

Workshop on development of a Community Sediment ModelJames P. Syvitski1, Chris Paola2, and Rudy Slingerland3

1. Institute of Arctic & Alpine Research, University of Colorado, Boulder, CO 80309-04502. St. Anthony Falls Laboratory, University of Minnesota, Minneapolis, MN 554143. Department of Geosciences, Penn State University, University Park, PA 16802

Workshop Report

Figure 1. Oblique view of Eureka, CA continental margin using multibeam and digitizedNOAA bathymetry. Land area is USGS 30-m DEM. VE = 5x., looking NE. CourtesyJames V. Gardner, US Geological Survey, Menlo Park, CA.


calling surface-process science. We at-tempted to sample the range of environ-ments, scientific problems, and societalapplications that the CSM effort wouldencompass. Again, we were struck by thediversity of approaches and backgroundsof the speakers, which ranged from sedi-mentary geology and geomorphologythrough oceanography and civil engineer-ing. Clearly, “surface-process science” isnot so much a community as the com-mon ground among several communities.We were reminded of a number of criti-cal aspects of surface dynamics: the rangeof scales (length and time); the com-plexity of the phenomena involved (sur-face dynamics is certainly one of the‘type fields’ for self-organization andpattern formation); and the profound con-nections to other fields, including biol-ogy, chemistry, geodynamics, atmo-spheric science, and hydrology. And ofcourse we were reminded of the widearray of potential applications, rangingfrom risk assessment and land manage-ment to resource exploration and im-plications of global warming.

The final day and a half of the meet-ing was devoted to developing a blueprintto be used to get the CSM effort off the

ground. Breakout groups addressed time-space scaling; developing a modulararchitecture; module definition; and de-velopment of a virtual CSM laboratory.The details of these deliberations will becast over the next few months into aWhite Paper to be written by six of theparticipants (David Furbish, Chris Paola,Rudy Slingerland, James Syvitski, GregTucker, and Pat Wiberg; please feel freeto contact any of us if you have commentsor questions). While the CSM web siteis still being constructed, readers are en-couraged to visit the site and view thepresentations http://instaar.colorado .edu/deltaforce/workshop/csm.html.

The most important summary con-clusion of the working-group efforts wasstrong endorsement for the CSM idea asdescribed in the first paragraph of thisreport. Beyond that, there was re-cognition that the CSM effort wouldlikely require several years to developeven a “draft” model suite; a central hostinstitution; support from a variety ofagencies (and perhaps industry); andmore management effort than any of uswould like to contemplate. Nothing ap-proaching the CSM project in scope orlevel of cross-disciplinary integration has

ever been attempted in the sediment-dy-namics community. With good co-ordination and leadership, the CSM willmultiply the effectiveness of numerousindividual efforts, and develop the open-ness between the modelers and field-ori-ented geoscientists. The manpower andskills are now available and, through ad-vances over the last decade, a criticalmass of basic algorithms describing sedi-mentary processes has been developed.

What’s in a name? If you’d like to dipyour toe in the water, you can think aboutwhat to call our fledgling effort. “Com-munity Sediment Model” is what we’vebeen using, but your input is welcome— if you have a catchy name for a sharedset of community-based models and soft-ware tools for investigating the dynam-ics of the surface of our (or other) planet’ssurface, let one of us know.

The Community Sediment Modelmeeting was supported by NSF throughthe MARGINS Source-to-Sink program.We were pleased to have with us NSF pro-gram managers Bilal Haq and Rich Laneand ONR program manager Dawn Lavoie.The meeting was held at INSTAAR, Uni-versity of Colorado, Boulder.

MARGINS Mailing List UpdateCut or copy this form and mail it to: MARGINS Office, Lamont-Doherty Earth Observatory,

P.O. Box 1000, Palisades, NY 10964, USA, or make changes online at

http://www.ldeo.columbia.edu/margins

Name:

Department:

Organization:

Street Address:

City:

Postal Code:

E-mail:

Your Home Page URL:

Your Department's Web Site URL:

State: Country:

Telephone:

Fax:

New

slet

ter

No. 8

, Sp

rin

g 2

00

2

Page 10 MARGINS Newsletter No. 8, Spring 2002 Workshop Report

This “second annual” Nankai TownMeeting was organized as a forum onprogress toward the goals of char-acterizing the seismogenic zone at theNankai margin, focusing especially onpotential IODP drilling. Scientific inter-est in this margin — one of the two U.S.MARGINS focus areas for seismogeniczone research — has long been high, butreached a new peak at the 2001 AGUmeeting with two full days of Nankaidevoted sessions.

Drilling and instrumentation of sub-duction plate boundary fault systems atseismogenic depths is one of the majorInitiatives identified in the IODP InitialScience Plan. The goals of such an Ini-tiative include the observation of pro-cesses related to the great earthquakecycle and tsunami generation. As the be-ginning of the IODP era looms closer, andwith the riser ship Chikyu under con-struction in Japan, attendees looked to thefuture, discussing hopes for drilling andobservatory installation at Nankai. Ac-cordingly, attention was focused on thepreliminary proposal, submitted in Oc-tober 2001 by 40 scientists from 6 coun-tries, to carry out such a study at theNankai margin (Proposal 603-Pre:Nankai Trough Seismogenic Zone Drill-ing and Observatory). This short pre-pro-posal, the first of its kind to IODP, out-lines the necessary drilling-based com-ponents of the Initiative, including mul-tiple legs of non-riser drilling to sampletrenchward inputs and up-dip portions of

faults, multi-stage riser drilling to 5 to 6kilometers below the sea floor, and em-placement of a comprehensive suite ofborehole instrumentation for long-termmonitoring.

The meeting began with refreshments(courtesy of the MARGINS Office) anda presentation on the pre-proposal and theoutcome of the first review by i-SSEP(interim Science Steering and EvaluationPanel; the primary IODP scientific re-view panel). This was followed by sev-eral short presentations meant to informattendees on recent progress toward geo-physical and geologic characterization ofthe Nankai margin.

Hisao Ito then placed the proposedNankai drilling in the context of otherpotential deep fault zone drilling projectssuch as the San Andreas Fault Observa-tory at Depth (SAFOD; part of the NSFEarthScope initiative), and the Chelung-pu (Taiwan) and Gulf of Corinth (Greece)drilling plans. The vision of a comingdecade of observatory installations in anumber of active faults in diverse tectonicenvironments quickened the pulse ofmore than a few jaded scientists.

The discussion which followed fo-cused on the uncertainties associated withproposing and planning such a complexproject when IODP decision-makingstructures are not yet operational. It wasgenerally agreed that detailed planningfor both riser and non-riser drilling needto begin very soon. With riser ship deliv-ery likely in early 2007, the time for plan-

Nankai Seismogenic Zone Experiment Town MeetingAGU 2001 Fall Meeting, San Francisco, CA, Thursday, December 13

Conveners: Gaku Kimura1, Harold Tobin2, Hitoshi Mikata3, Shuichi Kodaira3, and Pierre Henry4

1. Geological Institute, University of Tokyo, Tokyo 113, Japan2. Dept. of Earth and Environmental Science, New Mexico Tech, Socorro, NM 87801, USA

3. Japan Marine Science and Technology Ctr (JAMSTEC), Yokosuka, Japan4. Département Terre-Atmosphère-Océan, École Normale Superieure, 75231 Paris Cedex 05, France

ning a riser-based program is gettingshort, given the extensive geophysicalsurveys, tool development, and otherchallenges that must be tackled. Conven-ers and attendees alike agreed that the fullproposal must be developed thoroughlyyet quickly, so that it will weather theIODP scientific review process to be-come an IODP project without unduedelay. Accordingly, a Nankai-focusedworkshop was proposed by the conven-ers to develop a detailed science plan andfull proposal by October 1, 2002, withinput from the broadest possible rangeof disciplines as an essential ingredient.Consensus was reached that it is appro-priate to hold this workshop in the U.S.in the summer of 2002. The NanTro-SEIZE workshop is now scheduled forJuly 21-23 in Boulder, Colorado; pleaserefer to the ad on the facing page for moreinformation about this workshop.


Updip limit

Quantify lateral changes in the nature ofthe physical, chmeical, and hyrdogeologic

changes in the subduction fault

Image seismogenic zone usingearthquakes and artificial sources

Characterizing theincoming material by

non/riser drilling

Riser drilling of the seawardlimit of the seismogenic zone Sediment

surfacemeasurements

Boreholeobservatories

OOST

Seismogenic zone

INTERNATIONAL NANTROSEIZE WORKSHOPSampling and Instrumenting the Nankai Trough Seismogenic Zone

July 21-23, 2002 in Boulder, Colorado, USAAplication deadline June 7

Motivation for WorkshopThis international workshop is convened for two purposes:• To explore and better define the scientific opportunities created by access to the seismogenic zone of a subduction megathrust• To develop a robust experiment plan for carrying out this multi-faceted project at the Nankai Trough

We solicit the participation of all those interested in fault dynamics and earthquake processes from the broadest possible rangeof specialties, including seismology, structural geology, fault mechanics, borehole geophysics, geodynamics, hydrogeology, andgeochemistry.

Great subduction earthquakes are responsible for 90% of global seismic energy release and are among the most destructivenatural hazards. A fundamental goal of future ocean drilling is the sampling and long-term instrumentation of a subduction zoneplate interface at depth to improve understanding of faulting processes in the seismogenic zone. By 2006, the new drilling shipChikyu will have the capability to access depths of 6-7 km below the seabed and a borehole observatory in the seismogenic zonewill become feasible.

In pursuit of this goal, a preproposal was submitted to IODPin 2001 to carry out this experiment at the Nankai Troughoff southwestern Japan (available online at the SEIZE sec-tion of the MARGINS web site: http://www.ldeo.columbia.edu/margins). The Nankai Trough is perhaps the world’sbest studied convergent margin and locus of the longest his-torical record of great earthquakes and associated tsunami.Drilling and instrumentation of the plate boundary fault nearthe up-dip limit of co-seismic rupture will be part of a muchlarger multi-disciplinary Seismogenic Zone Experiment atthe Nankai Trough (shown above), including sampling ofthe inputs of crust, sediment, fluid, and heat to theseismogenic system. In concert with the San Andreas,Chelungpu (Taiwan), and other fault drilling efforts, theNankai project promises to offer unique data and opportuni-ties for hypothesis testing to advance our knowledge of faultdynamics.

Workshop InformationThe meeting will take place in Boulder, Colorado on 21-23 July, 2002. All those — from any country —potentially interested inattending this workshop arre requested to contact Harold Tobin via e-mail to [email protected], before June 7th, and provide thefollowing information:

• Name and institutional affiliation• Contact information (e-mail, postal addresses, and fax)• Research specialty and a very brief statement of specific interests within NANTROSEIZE

Please mark your calendar for July 21-23 and consider attending to help shape this unique scientific opportunity.

ConvenersHarold Tobin New Mexico Tech, USAGaku Kimura University of Tokyo, JapanHitoshi Mikada JAMSTEC-Deep Sea Research, JapanPierre Henry Ecole Normale Superieure, FranceShuichi Kodaira JAMSTEC-IFREE, Japan

Workshop Announcement


Two of the primary initiatives of theMARGINS program are the SeismogenicZone and the Subduction Factory. Cen-tral America is a central focus in each ofthese initiatives. A town meeting was heldon Monday, December 10, 6:30 pm-8:30pm, in Room 133 of the Moscone Cen-ter, to discuss the results of the July, 2001workshop in Costa Rica and to focus onseveral main initiatives that arose fromthe workshop. The July workshop wasorganized into the following sections:1. Role of incoming plate structure andplate kinematics on earthquake behaviorand tsunami generation;2. Role of fluid, mass, heat, and volatilefluxes on seismogenic behavior;3. Effect of incoming plate structure onarc geochemistry and volcano behavior;4. Crust and mantle fluxes and evolution;5. Effects on local populations

The results of this workshop werepublished in the Fall, 2001 issue of theMARGINS newsletter, pages 7-10. Dur-ing the town meeting, three major topicswere discussed:

A) A proposal for a deep seismic ex-periment across the volcanic arc in Cen-tral America. Discussion was led by SteveHolbrook (University of Wyoming). The

proposal includes two seismic transectsacross the arc and one along the arc, thelatter including Nicaragua. The cross-arclines would involve onshore explosionrefraction data, offshore MCS/OBS, andonshore-offshore shooting from both thePacific and Caribbean oceans. The re-sulting dense sampling would allow ac-curate imaging and seismic velocity de-termination beneath the arc, forearc, andbackarc, leading to a better understand-ing of the composition, flux, and fraction-ation of primary arc magmas in the Cen-tral American subduction factory.

B) A proposal was presented to carryout IODP riser drilling off southern CostaRica, where the seismogenic zone can bereached at relatively shallow depths (4to 5 km) in water depths less than onekm. In preparation for riser drilling, non-riser drilling is required. Drilling in thisarea allows initial penetration of theseismogenic zone with technology thatwill be well-tested by the time of the firstIODP riser drilling. It will also allow anexcellent comparison with drillingplanned off Southern Japan, because thelatter is an accretionary system and Cen-tral America is not. Discussion was ledby Roland von Huene.

On March 8-10, 2002, the Southern Cali-fornia Earthquake Center (SCEC) held aworkshop on research regarding the Cali-fornia continental borderland and thepossible organization of a BorderlandWorking group within SCEC. This group,

convened by Monica Kohler of UCLAand Tom Jordan of USC, is interested instudying ocean-continent interactions inthis transpressional plate boundary envi-ronment. A high scientific priority is tounderstand the onland seismic hazards

C) A proposal to carry out extensiveaerogravity and aeromagnetic surveyingof the offshore and onshore regions ofCosta Rica and Nicaragua was presentedby Garry Karner (Lamont-Doherty EarthObservatory). The availability of such acomplete and extensive data set for theCentral American community could beof outstanding benefit in understandingthe regional structure, rheology, andlithologic variability in this key region.It was pointed out that aerogravity mustbe flown significantly more slowly thanaeromagnetics and thus the two might bedecoupled in practice. Cesar Ranero dis-cussed the fact that much aeromagneticdata already exists for Costa Rica, andhe pointed out that the Pacific margin andocean plates off Costa Rica and Nicara-gua are well surveyed with magnetics andwith somewhat lower coverage of grav-ity data, put together by Udo Barck-hausen. Cesar Ranero also volunteeredto lead the effort for making that dataavailable for workers in Costa Rica. Theproposal must await a full evaluation ofthe available data before it can be pur-sued. Those interested in any of the abovetopics should contact the appropriate dis-cussion leader.

due to active faults and folds offshore inthe Borderland region.

The purpose of a SCEC BorderlandWorking Group, once formally estab-lished, would be to coordinate onshore-offshore southern California research

Borderlands WorkshopJoann M. Stock

Seismological Laboratory, California Institute of Technology, Pasadena, CA 91125, USA

Workshop Reports

Central America Town MeetingAGU 2001 Fall Meeting, San Francisco, CA, Monday, December 10

Conveners: Eli Silver1, Cesar Ranero2, Peter La Femina3, and Jeffrey Marshall4

1. Earth Science Department & Institute of Tectonics, University of California, Santa Cruz, Santa Cruz, California 95064, USA2. Marine Geodynamics, GEOMAR, 24148 Kiel, Germany

3. Marine Geology and Geophysics Division, Rosenstiel School of Marine and Atmospheric Science, Miami, FL 33149, USA4. Department of Geosciences, Franklin & Marshall College, Lancaster, PA 17604, USA


activities, archive and analyze existingdata, and plan new research activities in-cluding future experiments within theborderland. A white paper on the bor-derland research initiative is currentlybeing written, and information about thiseffort can be obtained from MonicaKohler ([email protected]).

The type of experiments needed in theBorderland include ocean observatories(for long-term monitoring of seismicity,crustal motions, biological, environmen-

MARGINS-NSF post-doctoral

Fellowship Program 2002

General InformationThe NSF-MARGINS Program provides support for post-doctoral researchers to conduct multi-disciplinary re-search with MARGINS research groups or individuals based at United States institutions by applying their exper-tise to problems related to the MARGINS initiatives. The Fellowships are designed so that recipients can choosethe research environment most beneficial for their scientific development and that of the MARGINS Program.

Eligibility and Award Information• Fellowships are awarded for post-doctoral study in fields supported by the four MARGINS initiatives (SEIZE,

SubFac, Source-to-Sink, and Rupturing Continental Lithosphere).• MARGINS particularly wishes to encourage applications from nationals of countries involved in the NSF-

MARGINS program, namely Costa Rica, Egypt, Japan, Mexico, New Zealand, Nicaragua, Papua New Guinea,Saudi Arabia, and the USA.

• Fellowships are intended for individuals in the early stages of their professional careers, typically within 5years of having been awarded their Ph.D. degree.

• Fellowships provide up to two years of support.• The MARGINS Fellowship award during 2002-2003 will be $40,000 for a 12-month tenure, $5,000 for

research costs per year, and an annual contribution of $5,000 as partial reimbursement for expenses incurredin support of the research.

• Application materials must be submitted to the NSF via the Fastlane electronic proposal submission system(http://www.fastlane.nsf.gov) by the deadline for the MARGINS Program, which this year is 1 November.

For a complete description of the fellowship award, conditions, application preparation information and instruc-tions, please review the information posted on the MARGINS web site:

http://www.ldeo.columbia.edu/margins/postdoc.html

tal, and biogeochemical markers); OBSand airgun studies using active sourcesto study the lithospheric architecture;OBS passive studies for earthquakemonitoring and receiver functions; heatflow studies; high-resolution gravity;studies to better constrain the geologicalhistory; and various techniques of imag-ing and sampling of active fault systems.

Although the Borderland is not partof any of the current MARGINS initia-tives, it encompasses part of the active

Pacific-North America boundary andadjoins to some extent the study area ofinterest in Rupturing of the ContinentalLithosphere in the Gulf of California/Salton Trough region. Many of the sci-entific questions of interest to the Mar-gins initiative are also relevant to theSCEC Borderlands Initiative, and pos-sible partnership activities between thetwo groups may become scientificallyadvantageous in the future.

MARGINS post-doctoral Fellowship

Page 14 MARGINS Newsletter No. 8, Spring 2002 Funded Programs

NSF Award number 0203650

Collaborative Research: Imaging themantle in the Central American sub-duction factory

Geoffrey Abers1 and Karen G. Fischer2

1. Department of Earth SciencesBoston University685 Commonwealth AveBoston, MA 02215

2. Department of Geological SciencesBrown UniversityBox 1846Providence, RI 02912

This award is for an 18 month deploy-ment of 43 PASSCAL broad bandseismometers in Nicaragua and CostaRica to seismically image the mantle“subduction factory” of the CentralAmerican volcanic arc in the region. Inaddition to the PASSCAL instruments,the PIs will also collaborate with CostaRican and Nicaraguan seismologists touse data from existing short period andbroadband instruments. The experimentwill image the mantle wedge with re-ceiver functions and other convertedwaves, together with regional waveforminversions. Tomographic imaging will beused to try to map the region of slab de-watering (and intermediate depth earth-quake generation), melt generation andmelt migration in the mantle wedge.Patterns of mantle flow will be inter-preted from shear wave splitting data, andcrustal structure will be inferred fromreceiver functions. Overall, the idea is toinfer the workings of the subduction fac-tory by combining seismic images of thecrust and mantle with the modeled inter-pretations of large observed differencesin magma composition along strike inthe arc volcanoes.


Hydrologic controls on the initial stateof the incoming plate: Costa Rica

Kevin BrownScripps Institution of OceanographyUniversity of California, San Diego9500 Gilman DriveLa Jolla, CA 92093-0220

Award is for a project to conduct a seriesof flux meter measurements alongtransects across hydrological boundariesin the down going plate off Costa Rica.This region is characterized by ano-malously low heat flow, except over re-gions of topographic highs that exhibitanomalously high heat flow values. Theflux meter measurements will test thehypothesis that the regions of low heatflow are characterized by downward fluidflow, while the high-heat-flow areas arecharacterized by upward fluid flow. Asecond portion of the project will be toreturn the areas on the accretionary prismwhere 35 flux meters were deployed aspart of a previous study, to collect pistoncores and heat flow measurements.Analyses of these cores will result in co-located temperature, chemical gradient,and direct fluid flux data sets that willprovide a more complete hydrologicalpicture of the incoming plate and theCosta Rica forearc.


Collaborative Research: Frictionaland Mineralogic properties of Sedi-ments entering subduction zones: con-trols on stress state and earthquakes

Kevin Brown1 and Michael B. Underwood2

1. Scripps Institution of OceanographyUniversity of California, San Diego9500 Gilman DriveLa Jolla, CA 92093-0220

2. Department of Geologic SciencesUniversity of Missouri, Columbia101 Geology BldgColumbia, MO 65211

This study will provide laboratory mea-surements of the coefficient of frictionof natural sediments entering the subduc-tion systems of Nankai, and Costa Rica.The frictional studies will be conductedin a combination of ring shear and directshear experiments at effective confinedstresses between 0.1-50 Mpa. Sampleswill be characterized by X-ray diffrac-tion (for bulk and clay mineralogy) grain-size, SEM/EDS geochemistry, and wetchemistry (for biogenic silica content).The mechanical properties will be com-pared with the clay mineralogy to deter-mine the effect of clay minerals on thecoefficient of friction. The study will as-sess the role of the smectite to illite tran-sition and opal to quartz reactions on con-trolling the up-dip limit of seismogenicactivity in subduction zones.


Determination of volcanic flux ratesand application to understanding re-gional geochemical trends and elementmass balances in Central America

Michael J. CarrDept. of Geological SciencesRutgers, The State University of New Jersey610 Taylor RoadPiscataway, NJ 08854-8066

Several important questions about thenature of the subduction process requirea transition from existing qualitative sub-duction signals, such as Ba/La and 10Be/9Be, to quantitative fluxes such as Ba fluxin gm/unit arc length/yr. This is accom-plished by employing 40Ar/39Ar datingtechniques to measure the ages of theolder units in several large Central Ameri-can volcanic centers. These new data,along with previously determined vol-ume measurements, enable the determi-nation of average volcanic flux rates fordifferent segments of the arc. Integratingvolcanic flux rates with regional geo-

Funded MARGINS Programs 2002These are the funded MARGINS Proposals for the fiscal year 2002. This information is also available at the awards database ofthe MARGINS web site at http://www.ldeo.columbia.edu/margins/MARGINSawards.html, together with abstracts of allNSF-funded MARGINS Projects.


chemical data allows an estimate of ele-ment fluxes to be made. From these inte-grated data several major problems arebeing addressed, including the physicalcause of along-strike variations in sub-duction signal in Central America, themass balance of elements cycling throughthe Central American arc, and the quan-tity of incompatible elements that aredelivered to the deep mantle through sub-duction.


Collaborative Research: Processescontrolling depositional signals of en-vironmental change in the Fly RiverSediment Dispersal system: rates andmechanisms of flood palin deposition

William E. Dietrich1 and Gary Parker2

1. Geology and GeophysicsUniversity of California, Berkeley313 McCone HallBerkeley, CA 94720-4767

2. St. Anthony Falls LaboratoryUniversity of MinnesotaMississippi River at 3rd Ave.Minneapolis, MN 55414

This project focuses on two fundamen-tal questions: 1) How does flow and sedi-ment routing through a lowland flood-plain system moderate short and longer-term variations in sediment delivery to-wards offshore depositional environ-ments? and 2) What controls the pro-portion of a river’s sediment load that isdeposited on its floodplain? It is hypo-thesized that net sediment loss to thefloodplains was highest during Holocenesea-level rise and, after near stabilizationof sea level, the proportion of the sedi-ment load deposited in the floodplain hasprogressively declined.

These two basic question are beingaddressed by comparing the flow andsediment routing processes, and the pro-portion of sediment lost to floodplains onthe middle Fly and lower Strickland Riv-ers. Historically, the Strickland carriedabout 7 times the load of the Fly and it ishypothesized that this larger load has ledto greater channel dynamics, steeperslopes, coarser bed, more elevated flood-plain and possibly a lower trapping effi-

ciency than the Fly. A numerical modelis being developed that is sufficientlymechanistic that it can address the ques-tions of damping and trapping efficiencyon the event and seasonal scale, yet sim-plified enough that it can also model theco-evolving bed grain size, channel slopeand floodplain topography, a crucial ca-pability for understanding the time evo-lution of trapping efficiency. Thoughambitious, many parts of the model havebeen assembled in previous research. Thehydrodynamic model accounts for theeffects of floodplain morphology andhydrology. The sediment routing includeseffects of channel migration and accountsfor the deposition and erosion of sedi-ment by grain size.

A field program is being conductedto document the flood wave dampingrates, the sediment trapping efficiency ofthe Strickland and Fly Rivers, and to pa-rameterize the numerical model. Quan-tification of floodplain morphology isbeing done through topographic surveysand analysis of remote sensing imagery.Intensive surveys of the velocity and sus-pended sediment fields are used to moti-vate and parameterize the hydraulics andsediment transport model. Short andlonger-term (less than 100 years) rate offloodplain deposition is being docu-mented from shallow cores. Extensiveflow and sediment monitoring data arebeing provided by Ok Tedi Mining, Ltd.on the Middle Fly and by Porgera JointVenture on the Strickland. Previous re-search on the Fly River enables the re-search focus to be on the Strickland River.


Convection of the mantle wedge abovesubduction zones

Greg HirthDepartment of Geology & GeophysicsWoods Hole Oceanographic InstitutionWoods Hole, MA02543-1050

This study will model the convection ofthe mantle wedge above the downgoingslab in subduction zones. Most of thebudget is to provide salary support forpost doc candidate Magali Billen to carry

out fluid dynamics based models ofwedge convection. The purpose of themodeling is to try to resolve the dis-agreement between petrologic evidencefor high temperatures (1200-1300°C) inthe wedge vs. thermal models that pre-dict much lower temperatures on the or-der of 700-800°C. This discrepancymight be explained by a low viscosityregion that allows convection in thewedge melting region at rates faster thansubduction rates. The modeling will ex-plore this possibility, as well as the ef-fects of several factors on the style andvelocity of convection: asthenosphereviscosity, localized low-viscosity zones,age of the overriding plate, slab dip, slabviscosity, slab age, slab velocity, and pos-sible non-linear rheology.


Indirect study of subducted oceanlithosphere at the Central AmericanMargin

Peter F. LonsdaleScripps Institute of OceanographyUniversity of California, San Diego9500 Gilman DriveLa Jolla, CA 92093-0205

The PIs plan mapping and sampling fea-tures on the Cocos and Nazca plates toprovide a basis for inferring the proper-ties of the subducted Cocos plate underCentral America. The basic premise isthat the Nazca plate south of Grijalva wasformerly contiguous with Cocos plateunder Nicaragua and parts of Costa Ricaand that this fossil plate boundary couldform an important structure in the down-going slab. Because a small fragment re-mains unsubducted, the investigators pro-pose to not only study it, but also it’s con-jugate off Peru, where much more re-mains. At that locality, the structure canbe mapped more thoroughly and the re-sults extrapolated to the subducted slabbeneath Costa Rica. Further, dredgingwill provide essential samples to measurethe composition of the lithosphere that isbeneath the Central American arc.

Page 16 MARGINS Newsletter No. 8, Spring 2002 Funded Programs


Collaborative research: The four-di-mensional pattern of Rifting in thesouthern Gulf of California

Peter F. Lonsdale1 and Paul Umhoefer2

1. Scripps Institute of OceanographyUniversity of California, San Diego9500 Gilman DriveLa Jolla, CA 92093-0205

2. Geology DepartmentNorthern Arizona UniversityFlagstaff, AZ 86011-4099

The PIs will carry out a swath bathym-etry survey of the southern Gulf of Cali-fornia, obtain 3.5 kHz, magnetic andgravity profiles and collect dredgesamples of the volcanic basement. Theobjectives are to test hypotheses con-cerned with the generic problems of howcontinental rifts are segmented tectoni-cally and whether this relates to asym-metries of faulting, how rift propagationoccurs tectonically and what type(s) ofmagmatism accompanies continentalbreak-up and earliest seafloor spreading.The Gulf of California is a MARGINS’focus site and this study will complementother research being carried out andplanned for this region.


What locks subduction thrusts?

Casey MooreEarth Sciences Board of StudiesUniversity of California, Santa Cruz1156 High StreetSanta Cruz, CA 95064

Under this award, the PI will examine awell-documented Eocene-Paleocene rockcomplex from a paleo subduction thrust,now exposed in Alaska, in order to quan-tify and understand the differences, at avariety of length scales, between the up-per aseismic parts of a subduction thrustand the lower seismogenic parts. Thisstudy will test the hypothesis that depo-sition of minerals in cracks strengthensand locks subduction thrusts in the peri-ods between major earthquakes. Duringfield work, the PI and a Ph.D. student will

document changes in structural fabric andmineral veins of various generations.Later lab studies will look at changes inphysical properties, and mineralogy un-der similar PT conditions as presentlyexist in the SW Japan subduction zone.Quantification of shear zone parameters,changes in mineralogy, intensity of pres-sure solution, density and porosity, andsize/shape of blocks and matrix, will al-low interpretations of the importance ofsimple sliding (aseismic) vs. stick-slip(seismic) behavior. Further, the results ofthe lab experiments can be used to inter-pret textures and structural features in-dicative of sliding, stick-slip, and heal-ing. These observations and measure-ments, including fluid inclusion studieswith Vrolijk, will be useful for testingideas about velocity weakening in actualsubduction zones, providing guidance forexperimentalists on what types of mate-rials are best for deformation studies, apreview of what will be seen in riser drill-ing at Nankai, and 10-100m scale con-straints on interpreting 3D seismic stud-ies in subduction complexes.


Processes controlling depositional sig-nals of environmental change in the FlyRiver Sediment Dispersal system:mechanisms and rates of shelf clino-form development.

Charles A. NittrouerSchool of OceanographyUniversity of WashingtonSeattle, WA 98195-7940

This project will investigate the processesof sediment transport and accumulationthat lead to development of the shelfclinoform in the Gulf of Papua off theFly River. The study will include a vari-ety of sampling and monitoring stationsfrom near the river mouth to the base ofthe clinoform that will provide time-se-ries observations on the spatial and tem-poral variation in present day sedimenttransport and accumulation. The study

will specifically investigate the role offluid muds as primary mechanism foracross-shelf transport of sediment thatleads to clinoform morphology. Corestudies including radioisotope measure-ments will provide information of sedi-ment transport and accumulation on sea-sonal to millennial time scales.


MARGINS Steering Committee highlightsOlaf M. Svenningsen


This is a new column in the newsletter inwhich highlights and important decisionsmade during the meetings of the MAR-GINS Steering Committee are madeavailable to the community.

The Steering Committee convened atLamont-Doherty Earth Observatory ofColumbia University in Palisades, NewYork, on March 13-14, 2002, and theagenda included the following items(items covered in other places in thisnewsletter are indicated in brackets):

1. Welcome by the MARGINS Chairand the Director of Lamont,

2. NSF Program managers’ report onMARGINS and MARGINS funding(see From the Chairman’s desk, page6, and Funded Programs, page 14),

3. Meeting reports (pages 8, 10, and 12)4. EarthScope — status and interaction5. Data management issues6. MARGINS Research Fellowships

(see announcement on page 13)7. Publication of science plans8. MARGINS Publications9. Watch dogs for the focus intiatives/

the Steering Committee’s responsi-bilities

10. Nominations for Steering Committeevacancies (see From the Chairman’sdesk, page 6)

Below are summaries of some of the de-cisions and discussion points that are notcovered elsewhere in this issue.

MARGINSUnder Item 2, Bilal Haq of the NSF re-quested that the scientific achievementsof the MARGINS Program should besummarized in the form of scientificmilestones or breakthroughs. Projects arenow funded within all of the four MAR-GINS Focus Initiatives, and NSF ex-pressed interest in a review of the pro-

gress for each intiative. Such a reviewwould contain:• the status of each component• what was envisaged, and• what has been achieved up until now?

The MARGINS Office will coordinatethese efforts and publish the results in theMARGINS newsletter.

EarthScopeThe MARGINS Steering Committee, to-gether with EarthScope and the Border-land Initiative, need to write a white pa-per about deploying ocean bottom seis-mometers (OBS’s) as a forerunner to aproposal to MRI.

Data management issuesThe NSF representatives pointed out thatthe Margins Data Policy now is a part ofOcean Sciences Divion’s data manage-ment policy.

Tom Shipley demonstrated The Uni-versity of Texas at Austin, Institute forGeophysics’ Seismic Reflection DataSearch Site (http://wedge.ig.utexas.edu/Web/main_html/intro.htm), and GarryKarner demonstrated the Lamont-Do-herty-MARGINS metadata web site(http://data.ldeo.columbia.edu/margins)

PublicationsThe Steering Committee decided that thescience plans for each intitiative, whichare presently available as downloadablePDF files on the MARGINS web site,should be printed published.

A MARGINS publications series istaking shape. The two first publicationswill be books resulting from the twoMARGINS Theoretical and Experimen-tal Institutes (TEIs), and each TEI is ex-pected to result in a book. Both the vol-ume from the “Inside the SubductionFactory”, and from the “Rheology andDeformation of the Lithosphere at Con-

tinental Margins” TEIs are in the finalstages of the pre-printing process.

Watch dogs for thefocus sites and intiatives

Each Steering Committee member is ex-pected to work actively to promote MAR-GINS in their respective community(with the assistance of the MARGINSOffice) and to represent their communityin the MARGINS Steering Committee.

This means that the it is the responsi-bility of Steering Committee members toactively promote new workshops, townmeetings, TEIs, and other MARGINSactivities. The MARGINS Office willassist in organizing and coordinating suchevents, but it is stressed that all MAR-GINS projects are proposal-driven, andthere is no budget for financing for ex-ample a TEI; the PIs will have to prepareand submit a proposal to the NSF in or-der to finance any such endeavour.

Steering Committee highlights

Page 18 MARGINS Newsletter No. 8, Spring 2002 Office News

MARGINS PublicationsOne of the MARGINS Office’s tasks isto keep track of the progress of the vari-ous components of the MARGINS Pro-gram, and to make the science resultsavailable on the MARGINS web site. TheMARGINS Steering Committee andNSF have decided that every publicationthat is produced within MARGINS,needs to obtain a publication number.These will be used to organize an onlinedatabase, containing literature references,abstracts and keywords of MARGINSpublications. Only publications producedwithin projects funded by the MARGINS-NSF Program are eligible for registration.

To obtain a MARGINS PublicationNumber, authors of any publicationfunded by the NSF-MARGINS Programare requested use the web form at:

http://www.ldeo.columbia.edu/margins/PublicationReg.html.

Publication numbers should be re-quested whenever a manuscript is ac-cepted for publication, for the number tobe included in the Acknowledgements orat some other appropriate location in the

MARGINS Office NewsOlaf M. Svenningsen


publication procedure. Specific biblio-graphic information, like page numbers,can be amended later. Full instructionson how to use the form are posted on theweb.

If cut-and-paste is used to enter, forexample, authors, abstract and keywords,the form takes about one to two minutesto complete.

Conference contributions (talks andposters) will not receive an offical num-ber, but authors are still strongly encour-aged to submit the bibliographic infor-mation via the form for inclusion in thereference database. As a means to pro-long the life of conference contributions,the submittal of summaries of posters andtalks, including graphics, to the MAR-GINS Office for posting on the web siteis encouraged.

Web site updateIn the previous issue (#7) of this news-letter, some statistics for the use of theMARGINS web site were summarized.The development since then has beenvery positive, and the user statistics forthe last 11 months is shown in Figure 2.

At the beginning of 2002, a new web

counter was installed, which makes de-tailed tracking of web site use possible.Also, at the beginning of the year, theMARGINS-NSF Awards Database waspublished on the web site. This, togetherwith some other enhancements, resulted

Figure 1. The Publication Registraton format the MARGINS web site

0 1,000 2,000 3,000 4,000 5,000 6,000

AprilMarch

FebruaryJanuary2002:

DecemberNovember

OctoberSeptember

AugustJuly

June2001:

Figure 2. Visits to the MARGINS web sitefrom June 2001 to April 2002

in a substantial increase in the numberof visits to the web site. The increasedfrequency of hits has remained high thro-ughout the winter and spring.

IMPORTANT:MARGINS-NSF logo use

We would like to revisit the need to ad-vertise the results, work and successes ofthe MARGINS Program at national andinternational conferences and meetings.In a room full of posters, being able toeasily recognize what projects are fundedby which program is particularly impor-tant to the NSF program managers. Anexcellent way to do this is by acknowl-edging MARGINS in: 1) Research pa-pers funded by NSF-MARGINS, and 2)Including the MARGINS logo in posterpresentations by using the MARGINSlogo:

Accompanied by the text: “Research sup-ported by NSF-MARGINS [award # ...]

The MARGINS-NSF logo can be down-loaded in a number of different formatsand sizes from the following site:

http://www.ldeo.columbia.edu/margins/Logos.html


Garry Karner, ChairmanLamont-Doherty Earth Observatory61 Route 9W, P.O. Box 1000Palisades, New York 10964Tel: (845) 365-8355Fax: (845) 365-8156e-mail: [email protected]: http://www.ldeo.columbia.edu/karner/ QBA

.word.html

Frederick M. ChesterDepartment of Geology & GeophysicsMail Stop 3115College Station, TX 77843Tel: (979) 845-3296Fax: (979) 845-6162e-mail: [email protected]: http://geoweb.tamu.edu/Faculty/chesterf/

index.html

Rebecca J. DorseyDepartment of Geological Sciences1272 University of OregonEugene, OR 97403-1272Tel: (541) 346-4431Fax: (541) 346-4692e-mail: [email protected]: http://darkwing.uoregon.edu/~dogsci/

dorsey/rjd.html

Marc M. HirschmannDepartment of Geology and Geophysics108 Pillsbury HallUniversity of MinnesotaMinneapolis, Minnesota 55455Tel: (612) 625-6698Fax: (612) 625-3819e-mail: [email protected]: http://www.geo.umn.edu/orgs/

hirschmann/home.html

Greg HirthDepartment of Geology and GeophysicsWoods Hole Oceanographic InstitutionWoods Hole, MA 02543Tel: (508) 289-2776Fax: (508) 457-2183e-mail: [email protected]: http://www.whoi.edu/science/GG/dept/cv/

jgh.html

Scott LinnemanGeology Department and Science Education GroupWestern Washington University516 High StreetBellingham,WA 98225-9080Tel.: (360) 650-7207Fax: (360) 650-7302e-mail: [email protected]: http://www.ac.wwu.edu/

%7Elinnems/index.htm

Anne MeltzerDept. of Earth & Environmental SciencesLehigh University31 Williams DriveBethlehem, PA 18015-3188Tel.: (610) 758-3660Fax: (610) 758-3677e-mail: [email protected]: http://www.ees.lehigh.edu/,

http://www.earthscope.org

John MillimanVirginia Institute of Marine ScienceCollege of William and MaryP.O. Box 1346Cloucester Point, VA 23062Tel: (804) 684-7105Fax: (804) 221-3540e-mail: [email protected]: http://www.vims.edu/physical/faculty/

milliman_jd.html

Simon PeacockDepartment of GeologyArizona State UniversityP.O. Box 871404Tempe, Arizona 85287-1404Tel: (602) 965-1733Fax: (602) 965-8102e-mail: [email protected]: http://geology.asu.edu/people/faculty/

peacock/index.html

Thomas H. ShipleyInstitute of GeophysicsUniversity of Texas4412 Spicewood Springs Road, Building 600Austin, Texas 78759Tel: (512) 471-0430Fax: (512) 471-6338e-mail: [email protected]: http://www.ig.utexas.edu/staff/tom/tom.htm

Eli A. SilverUniversity of California, Santa CruzEarth Science Department & Institute of Tectonics1156 High StreetSanta Cruz, California 95064Tel: (831) 459-2266Fax: (831) 459-3074e-mail: [email protected]: http://www.es.ucsc.edu/personnel/Silver/

Rudy SlingerlandDepartment of GeosciencesPenn State University503 Deike BldgUniversity Park, PA 16802Tel: 814-865-6892Fax: 814-863-8724e-mail: [email protected]: http://www.geosc.psu.edu/People/Faculty/

FacultyPages/Slingerland/index.html

Joann StockSeismological Laboratory 252-21California Institute of Technology1200 E. California Blvd.Pasadena, California 91125Tel: 626-395-6938Fax: 626-564-0715e-mail: [email protected]: http://www.gps.caltech.edu/~jstock

Patricia WibergDepartment of Environmental SciencesUniversity of VirginiaP.O. Box 400123Charlottesville, VA 22904-4123Tel: (434) 924-7546Fax: (434) 982-2137e-mail: [email protected]: http://www.evsc.virginia.edu/faculty/people/

wiberg.shtml

Douglas A. WiensDepartment of Earth and Planetary SciencesWashington University1 Brookings DriveSt. Louis, Missouri 63130-4899Tel: (314) 935-6517Fax: (314) 935-7361e-mail: [email protected]: http://epsc.wustl.edu/admin/people/wiens.html

MARGINS Steering Committee Members

Bilal HaqMarine Geology and Geophysics Program

Division of Ocean SciencesTel: (703) 292-8581Fax: (703) 292-9085

e-mail: [email protected]

Paul DauphinOcean Drilling Program

Division of Ocean SciencesTel: (703) 292-8581Fax: (703) 292-9085


David FountainTectonics Program

Division of Earth SciencesTel: (703) 292-8552Fax: (703) 292-9025


Contact Information

NSF Program DirectorsNational Science Foundation, 4201 Wilson Boulevard, Arlington, Virginia 22230

MARGINS OfficeLamont-Doherty Earth ObservatoryOceanography Building, room 30561 Route 9W, P.O. Box 1000Palisades, New York 10964-8000Tel: (845) 365-8665, or 8509Fax: (845) 365-8156e-mail: [email protected]: [email protected]: http://www.ldeo.columbia.edu/margins

This newsletter is supported by the National Science Foundation underGrant No. OCE 00-79660. Any opinions, findings, and conclusionsexpressed in it are those of the authors and do not necessarily reflect theviews of the National Science Foundation.

New

slet

ter

No. 8

, Sp

rin

g 2

00

2

Pre-SortedFirst Class MailU.S. Postage

PAIDPermit No. 3593

NEW YORK

NY 10027

Upcoming Meetings:• The Geological Society of America2002 Annual Meeting &

ExpositionOctober 27-30, 2002 in Denver, Colorado

—• Chapman Conference on

Continent-Ocean Interactions within the East Asian

Marginal SeasNovember 27-30, 2002 in San Diego, California

—• AGU 2002 Fall Meeting

6-10 December 2002, San Francisco, California—

For more information on meetings, see the MARGINS web site:http://www.ldeo.columbia.edu/margins

Documents

Collaborative Visualization in Earth · images onto wall-sized cylindrical screens (Figure 1). These systems allow users to combine and explore data and images in innovative ways