C COONNTTEENNTTSS - Remote sensing a nutshell GRSG represents a true ... At this grass roots level a prime task is ... students require an understanding of the integrative tools of

GRSG Newsletter Issue 22 April 1998 Page 1

CCCOOONNNTTTEEENNNTTTSSS

Want to know more Inside front cover

Contents 1

Editorial 2

Group News 6

Members‟ News 7

Sensor News 11

Letters 14

Company News 17

GRSG Corporate Members 20

Product News 22

GRSG Meetings 26

Other Meetings 27

MDSG Greenwich - Abstracts 31

Feature Article 46

Questionnaire 51

Summer Competition 54

Message from Philippa 55

International Contacts Inside back cover


EDITORIAL

Geological remote sensing and the state of our art

In common with previous contributors to this page, I have glanced through back

numbers for inspiration. Issues raised over the last few years include the joys of

fieldwork, the consultant‟s lot, relationships with “uncles” (RSS and the Geological

Society), the future of geological remote sensing, GRSG meetings strategy, remote

sensing in degree programmes and a celebration of the renaissance of photogeology.

As the editor is breathing down my neck, I will provide a collage, loosely based on

some previous editorial themes, newsletter contributions and bees I have in my

bonnet.

Whither Geological Remote Sensing? As we all know, membership of GRSG covers

a wide range of working environments: companies, consultants, researchers,

educators, students and government agencies to name a few. GRSG itself is affiliated

to the RSS which likewise interests itself in a very wide range of RS applications, of

which geology is just one. The SIGs of the Geological Society are equally numerous.

In a nutshell GRSG represents a true Diaspora of interests and this lies at the root of

the meetings conundrum recognised by Alistair in his discussion of GRSG sessions

at RSS97 and Geoscience 96 (Editorial, issue 21). At the back of my mind is the

fundamental question “do most geologists appreciate the full contribution that

modern remote sensing can make to their work, whatever their field of specialism?”

We have to spread the word and encourage geologists who are not remote sensors to

acquire least a basic understanding of remote sensing and its usefulness. We still

have to fight old prejudices. Current trends should make this an easy task.

Developments in imaging spectrometry, field-based PIMA, the potential of


hyperspectral and metric resolution from spaceborne sensors are all contributing to an

environment in which remote sensing can realistically fulfill its early promise. At the

same time, digital photogrammetry and the prospects raised by the new generation of

commercial satellites are giving a new lease of life to the skills of photogeological

interpretation as Geoff Lawrence noted in his lyrical editorial of Issue 14. It has even

been suggested, according to Eric Peters‟ contribution to GRSG‟s lunchtime session

at ERIM (issue 21), that image processing may take a back seat in the face of this

resurgence. In such a generally favorable environment GRSG should continue to put

on its own “shows” but, as Alistair pointed out, it is also essential to promote wider

awareness through the medium of joint conferences with other SIGs. To the same end

we should see more collaborative involvement of remote sensing in a wide range of

geoscience research areas and we must make sure that the needs of our students are

properly catered for.

At this grass roots level a prime task is the promotion of remote sensing among the

rising generation of geoscientists, and the training offered by UK geoscience degrees

needs to recognise this important fact. Remote sensing is still far too often a “bolt

on” part of another course, or taught as a module in isolation, sometimes for geology

students but by non-geologists, and often with a minimum of “hands on” experience.

Likewise, students require an understanding of the integrative tools of GIS, still too

commonly excluded from geoscience degree programmes. However it is delivered in

classwork, remote sensing is an intensely practical subject and, as Vicky reminded us

(Editorial, issue 17), good fieldwork provides an essential underpinning to good

remote sensing (and vice versa). Yet I wonder how much remote sensing commonly

goes into undergraduate preparation for honours field projects. Is there an attempt at

preliminary photogeological interpretation? Is use made of the widely available

national TM and SPOT datasets? Do students take stereopairs and pocket

stereoscopes into the field? Are orthoimages used as a mapping base? I think a

review would show a wide range of variation but with a disturbingly large number of

negatives, or am I wrong? While we wait for geoscience training to catch up with


reality, or questionnaire responses from colleagues to correct my misconceptions (see

back pages) what can we do?

Well, first, let‟s acknowledge the success and quality of the Newsletter, maintained

over several years by Vicky and with a continuation of the same tradition under

Philippa as the new Editor. I think we all recognise this as an important component

of what GRSG has to offer members in addition to the meetings. We know the

membership situation has been steady over recent years and that there has been an

encouraging increase in corporate membership (report on AGM is issue 21). Do we

have enough academic members, does the subject have enough “champions” in

Departments around the country and do we have enough student members? I don‟t

think so. Let‟s see a big effort from all GRSG members to promote membership

among all colleagues and students that they have access to. Finally, if you are in

higher education and want a more objective assessment of the state of remote sensing

teaching in undergraduate geoscience courses then please complete the questionnaire

at the back of this issue. I will present the data without naming individual

contributors or departments.

Andy Bussell

School of Earth Sciences, University of Greenwich


Looking for slicks. Geoff sea-truthing OBS.


GROUP NEWS

Membership renewal

The 1998 reminders for membership renewal will be in the post to you all soon, so

have your chequebooks dusted off in readiness.

GRSG Student Prize

The GRSG Committee is currently reviewing entries for the 1997 GRSG Student

MSc Thesis Prize. The results will be published in the next issue of this Newsletter.

New committee members

The present GRSG Committee has co-opted Martin Wooster as a new committee

member for 1998.

„Old‟ committee members

Stuart Marsh is at present, a man behaving badly. We suspect that this maybe a

cunning plan to get himself sacked as Secretary. Anyone who feels that they could

take on the task of a) convincing Stuart that he is marvelous at his job and should

therefore stay, or b) becoming Secretary, should make themselves known to the

Committee, ASAP.


MEMBERS’ NEWS

At last: News from Thailand

In case you were wondering what has happened to the “old” Newsletter Editor (you

weren‟t? well, you‟re going to hear anyway!) she left the Natural Resources Institute

(NRI) at the end of December 1997 and has now resurfaced at the Asian Institute of

Technology (AIT) in Bangkok, Thailand. The posting is funded by the UK

Department for International Development (DFID, formerly known as ODA) and

takes the form of an attachment to the Aquaculture Outreach programme, based

within the Agricultural and Aquatic Systems unit at AIT.

Well.....She writes:

I have now been in Bangkok for five weeks and am just about getting used to the heat

and humidity (…and what about the fact that Bangkok is sinking several centimetres

per year: see the differential interferogram!!) The traffic though is something else.

Having become slightly tired of lots of short overseas trips, mainly to Africa, I

decided that it would be good to get some long term overseas experience under my

belt, and that is more or less the story of how I ended up here. I had slowly been

weaned off geological remote sensing during my time with NRI, and my role at AIT

is perhaps even further removed from the GRSG world! The brief I have is to assess

the possible role of GIS and remote sensing in the development of a feasible

approach for resources assessment and planning for aquatic resources development,

within the Aquaculture Outreach programme.

The potential contribution of Aquaculture to sustainable development, in the context

of the carrying capacity of natural aquatic ecosystems and man-made agro-

ecosystems, depends on promotion, both to intensify production by existing farms,

and to facilitate new entrants into aquaculture. The Aquaculture Outreach


Programme is engaged in capacity building with national research and educational

institutions involved in aquatic resources planning and management in four countries

of mainland southeast Asia: Cambodia; Lao PDR; Thailand; and Vietnam.

AIT has a well-developed remote sensing program, known as the STAR program

(Space Technology Applications and Research). A recent STARinitiative has been to

run a five-day workshop on the use of Radarsat data, with support from various

agencies and Radarsat International. This was well attended by delegates from south-

east Asia and has raised the profile of the satellite in the region. Another initiative,

jointly with the Asian Association on Remote Sensing and with further support from

National Space Development Agency of Japan and the National Research Council of

Thailand, has been the establishment of Asian Centre for Research on Remote

Sensing. ACRoRS is self-funded, non-profit research centre dedicated to the

development and promotion of remote sensing research and activities in Asia-Pacific.

Other current projects of the STAR program include a cassava monitoring project, a

malaria project, and a remote sensing research promotion project.

In case you were wondering about AIT, it originated in 1959 to help meet the

growing need for advanced engineering education in Asia. In November 1967, the

Institute became an autonomous international institution with the power to award

degrees and diplomas. It currently offers advanced (postgraduate) education in

engineering, science, planning and management through a range of activities, at

levels and intensities from doctoral research to short-term training. There are over

one thousand students, mostly from Asia, and 200 faculty and international staff,

addressing the need for more and better trained personnel for key positions in private

and public sectors throughout the region. The Institute is supported by donor

governments, international agencies, foundations, business organizations and

individuals, Asian and non-Asian. Find out more at: http://www.ait.ac.th

Vicky Copley [email protected]


Bill Di Paulo moves

Bill Di Paulo would like to let everyone know that he left Unocal last August, to

return to his home territory of Evergreen, Colorado (where he is now looking for

consultancy work), and where he and his wife now reside at the following address:

P.O.Box 3877, Evergreen, Colorado 80437-3877, USA

Tel: +1 303 674 8533 email: [email protected]

Short but sweet from John Berry

..............the Geosat Committee has moved to UT El Paso, Texaco's TEEMS is

operational, and that the long-awaited vol. 3 of the Manual of Remote Sensing is

back on track.

Reminder: did you pay your 1998 dues……or do we have to persuade you?


Geoff bows out from picture-gathering It‟s goodbye to one of our backroom boys, Geoff Lawrence, who is taking half of his

company, the Really Easy Imaging Company Limited, off to Houston in the near

future. Surprised by the strength of the oil industry and civil engineering markets in

the States, in spite of all the “downsizing”, TREICoL reckons that US technology

and graduates have the edge over the European varieties. Geoff plans to oversee both

offices but will continue to be based in the UK some of the time. Geoff, who was

GRSG‟s founding Chairman, has been responsible for the irrelevant and usually

irreverent pictures (…and that‟s not all…Ed) that have spread like a fungus in the

Newsletter. So, offers please for your pictures and cartoons for the Newsletter.

It’s getting a bit cushy here in UK, Mabel…why don’t we try Houston?


SENSOR NEWS

LANDSAT-7 LAUNCH DELAYED

The Landsat-7 Earth science spacecraft will not be launched in July 1998 as planned,

due to necessary changes in the design of the electrical power supply hardware for

the spacecraft's main instrument. A new target launch date will be set by NASA

officials after completion of instrument thermal vacuum tests scheduled for this July.

During a series of instrument-level thermal vacuum tests beginning in December 1997, a power supply

on the Enhanced Thematic Mapper Plus (ETM+) instrument failed twice. ETM+ is Landsat-7's only

science instrument. Because of the most recent failure in January, both internally redundant power

supplies were returned to their manufacturer. Completion of vacuum testing will be delayed while the

power supplies are being repaired, which will consequently delay the launch.

The Enhanced Thematic Mapper was designed and built by Raytheon (formerly

Hughes) Santa Barbara Remote Sensing, Santa Barbara, CA. The Landsat-7

spacecraft was built by Lockheed Martin Missiles and Space, with integration of the

instrument and spacecraft conducted at the company's facility in Valley Forge, PA.

In particular, the science instrument on Landsat-7 will continue a database of high-

resolution Earth imagery begun in 1982 by the Landsat-4 Thematic Mapper. As

changes occur on the Earth's surface due to natural or human-induced events,

scientists will be able to study these recent changes with the aid of the archive of

similar imagery. Applications include agriculture, forestry and urban planning.

Landsat-7 contains several technological improvements over previous Landsat

satellites and their instruments. These improvements include better instrument


calibration and a solid state data-recorder capable of storing 100 individual enhanced

Thematic Mapper images of the Earth. This capability will enable Landsat-7 to

update a complete global view of Earth's land surfaces seasonally or approximately

four times per year.

NASA also is developing an Advanced Land Imager instrument and related small

spacecraft technology. This will enable future follow-on measurements to be made by

a sensor that is one-fourth the mass of the enhanced Thematic Mapper and uses only

20 percent of the electrical power, while reducing the instrument's cost by 75 percent.

Earth-viewing satellite to focus on education & science

NASA is developing plans for a small satellite which could provide continuous views

of the Earth by the year 2000. The satellite would contain a high-definition television

camera and an eight-inch telescope into an orbit at a unique vantage point a million

miles from Earth where it could provide 24-hour views of the home planet. It would

orbit at a point in space where the gravitational attraction of the Sun and the Earth

essentially cancel one another out, allowing the satellite to constantly view a fully

sunlit hemisphere.

Early plans envision a 330-pound satellite linked to Earth through three simple, low-

cost ground stations equally spaced around the globe to provide continuous downlink

capability. One new image would be downlinked every few minutes. The satellite

would be developed and launched within two years of a competitive selection

process. College students would participate in the design and development of the

spacecraft, and student teams would operate the ground stations. The total mission

cost, including launch and operations, would not exceed $50 million.

Expected launches for 1998

Satellite launches, from various nations, in the coming year, are as follows:


Satellite

Sensor Resolution Launch date

Ikonos-1 Op 1m March

Clark Hyperspectral 3m Post-March

if at all

CRSS-1 1m Spring

EOS AM-1 15m June 30

EROS A

(USA/Israel)

Op 1m Summer

Ikonos-2 Op 1m October

Quickbird Op 1m Late autumn

NMP/EO-1 Hyperspectral 10m 315 bands Late autumn

OrbView 3 Hyperspectral 1m End of year

All launches are from USA unless otherwise stated

LETTERS


Dear Readers,

For those of you who wonder where the old Chevron Remote Sensing Group and Donn Walklet ended

up, read on .- This note is extracted from a Press Release that is going to be published in GIS World

next month. I believe the GRSG membership, in particular, will find items of interest within the Press

Release.

<<International Alliance Forged For Resource Development

The MapFactory Recognized for Map Technology Leadership

February 17, 1998

The MapFactory, Inc., a company offering leading edge technology to create mapping information for

business applications, announced an alliance with Harrods Natural Resources Inc., a company

established by the Chairman of Harrods, Mohamed Al Fayed, to engage in exploration for oil and

minerals worldwide.

The MapFactory was established to bring together experts in the use of satellite

imagery and digital mapping.....it provides products and services for

telecommunication ...companies and commercial real estate developers, as well as

geologists engaged in oil and mineral exploration......

Mr. Al Fayed was the founding investor of The MapFactory, recognizing the need to

bring together the best talent and technology for map creation. Donn Walklet who

has over 25 years of experience in the commercial application of satellite imagery

heads the company as its President and Chief Executive. He has gathered a team of

mapping veterans from a major petroleum exploration company '...(Pat Caldwell,

Peter Goodwin, Hattie Davis, Mike Quinn, Mark Choiniere and Jim Ellis)...' as well

as other experienced computer mapping professionals....

Mr. Walklet observed,"....The Harrods name is associated worldwide with quality of

product and service, and we anticipate bringing digital mapping to an unparalleled

level of excellence as a result of this collaboration....>>


The new company is expanding the vision and roles of the former big oil company

employees. We all enjoyed reading the 20 August 1997 GRSG Newsletter article (p.

7) entitled "The oil industry lets more remote sensors go" about us. As noted in the

article, Donn continues to be "enduring" and Jim Ellis will be glad to entertain

inquires - however, for the latest update, please visit our Web Page at

www.mapfactory.com. We are introducing a new product line within a few months

that we hope will attract much attention (and sales!) across the commercial mapping

marketplace.

Best regards from Jim Ellis

The MapFactory, Inc., 3000 Oak Road, Suite 200, Walnut Creek, CA 94596 U.S.A.

Tel: 510-280-8765 Fax: 510-280-8760

www.mapfactory.com [email protected]

mailto:[email protected]


The Full Fayad……..hats off and salute the MapFactory!


COMPANY NEWS

ASD introduces FieldSpec OEM

Analytical Spectral Devices, Inc. (ASD) introduces FieldSpec OEM, a spectrometer designed for

industrial applications. The system features an overall spectral range of 300nm to 2500nm, through the

use of up to four internal spectral modules. Specific ranges can be tailored for individual applications

by combining these modules.

ERDAS Training Schedule

A number of IMAGINE and image processing training schemes are being run at the

ERDAS Education Centre in the winter and spring months of 1998 (February, April,

May and June).

Details from: ERDAS Education Centre, Telford House, Fulbourn, Cambridge, CB1 5HB, and UK.

Tel: +44 (0)1223 880802 Fax:+44 (0)1223 880160

ER Mapper Training Schedule

ER Mapper wishes to announce their training schedule in the UK for 1998:

Oil & Gas applications March & May 1998 Land Applications/Reseller Training March - July 1998 Professional Sales Course for ER Mapper Resellers March - July 1998 For details contact [email protected]


NRSCL to distribute ER Mapper

The National Remote Sensing Centre Limited (NRSCL) of the United Kingdom has

entered an agreement with Earth Resource Mapping to act as an ER Mapper Dealer.

ER Mapper expands to South Africa

GeoWorld has entered an agreement with Earth Resource Mapping to act as an ER

Mapper Master Dealer for the South African GIS market. GeoWorld are the approved

Autodesk distributor for Southern Africa and have established an executive network

throughout the region to supply Autodesk GIS products for a range of markets.

ER Mapper Chosen for Hyper-Spectral Remote Sensing

ER Mapper has been selected by Comserve APSE for use in the THEMAP system.

THEMAP, a jointly developed technology between Comserve APSE and CSIRO, is

an advanced hyper-spectral airborne remote sensing system designed for commercial

application. After over 7 years of R&D invested from both organisations it is now

undergoing operational testing in Eastern Indonesia under some of the most

demanding logistical and environmental conditions possible for introduction into key

world markets.

Information on THEMAP can be viewed at

http://www.dwr.csiro.au/commercial/themap



GRSG CORPORATE MEMBERS

The following were Corporate Members in 1997:

ERDAS (UK) Limited Telford House, Fulbourn, Cambridge, CB1 5HB, U.K.

Tel: 01223 880802 Fax: 01223 880160

email: [email protected]

Floating Point Systems UK Ltd. Ash Court, 23 Rose Street, Wokingham,

Berkshire, RG40 1XS Tel: +44 (0) 118 977 6333 Fax: +44 (0) 118 977 643

E-Mail: [email protected] http://www.floating .co.uk

http://www.rsinc.com

Natural Environment Research Council

Directorate of Science and Technology, Polaris House,

North Star Avenue, Swindon SN2 1EU

Tel: +44 (0)1793 411500

PCI Geomatics Group Ltd. 5 Shenley Pavilions, Chalkdell Drive, Milton Keynes,

Buckinghamshire MK5 6LB

Tel: (44) 1908 523300 Fax: (44) 1908 521511

Email: [email protected] http://www.pci.on.ca/

Rio Tinto Mining & Exploration 4 The Broadway, Newbury,

Berkshire, RG14 1BA U.K. Tel: +44 (0)1635 48511

Fax: +44 (0)1635 35542 or 35947

Corporate Membership renewals are in the post to you now


New Corporate Members in 1998 are:

NPA Group

Crockham Park, Edenbridge, Kent, TN8 6SR

Tel: 01732 865023 Fax:017322 866521

Earth Resource Institute of Michigan (ERIM)

P.O. Box 134001,

Ann Arbor, Michigan 48113-4001, USA

Tel: +1 313 994 1200 Fax: +1 313 994 5123

Analytical Spectral Devices (ASD) Inc.

5335 Sterling Drive,

Boulder, Colorado USA

Tel: +1 303 444 6522 Fax: +1 303 444 6825

Email: [email protected] Web: http://www.asdi.com


PRODUCT NEWS

ERDAS software news:

ERDAS Imagine 8.3.1 for MS Windows NT and 95

This latest version provides new technical features. The ability to edit ESRI Arc/Info

format vector GIS layers is now available in the core module IMAGINE

EssentialsTM. New importers are included for NLAPS Data Format (NDF), IRS-1C in

EOSAT Fast Format v.C, IRS-1C in Euromap format and Daedalus airborne scanner

data. Fuzzy classification tools have been added to IMAGINE Professional, including

automated decision-making tools for greater flexibility in map production.

OrthoMAXTM 8.3

Highly accurate, total solution for generating elevation models and orthoimages.

Notable additions in this release are expanded stereo viewing and editing capabilities

with more digitising tools. The software generates digital terrain models and

orthoimages from aerial photography and SPOT satellite imagery. There is also a

new ASCII import/export tools to allow input and output of TINs and GCPs.

Mobile Mapping System

ERDAS announces completed development of the Mobile Mapping System from

Lockheed Marin Corporation (LMC) Management and Data Systems (M&DS). The

new system, called LM3S, is a self-contained integrated GIS/Image processing

system suitable for military, civil or commercial applications.. Mounted on a High

Mobility Multipurpose Wheeled Vehicle (HMMWV), the LM3S can receive map

and satellite data, construct or update maps and conduct terrain analysis anywhere.

PCI Geomatics Group press release:

SPANS 7 - the new version features new SPANS AuthorTM module, 24-bit raster

support and import, and charting enhancements. The Author module allows the


development of Graphical User Interfaces (GUI). The new version also includes

essential analysis and modeling operations in the form of SPANS TopographerTM,

ProspectorTM and PioneerTM.

NIMA Pathfinder98 - Geomatics software suite (remote sensing, digital

photogrammetry, image processing, spatial analysis and digital cartography) have

been selected for potential inclusion in the Pathfinder98 initiative of the US National

Imagery and Mapping Agency (NIMA).

Geocomp-n - PCI Geomatics Group has been awarded the contract to enhance the

Geocomp processing system from Natural Resources Canada, based on specifications

of the Canada Centre for Remote Sensing (CCRS). This will involve software from

the EASI/PACE® remote sensing system and components from the Sky to MapTM

geomatics suite. Geocomp-n is the second enhancement to the original Geocomp

system and will be developed in a modular fashion so that it can be updated to

support future sensor and other hardware developments.

ER Mapper Announces FREE ER Viewer

Earth Resource Mapping, announces the FREE release of ER Viewer. ER Viewer is

totally Microsoft compliant and allows you to view ER Mapper detests and

algorithms whilst also handling TIFF, GeoTiff, BMP and HDR images. ER Viewer is

also capable of „Real Time‟ roaming and zooming.


Floating Point Systems announce release of Version 3.0 of the ENVI Image Processing Software

Well established as the prime software to manipulate and analyse hyperspectral imaging data, ENVI is

steadily consolidating its position as a front-line image processing package for workstations and PCs,

up there with ER Mapper, ERDAS (both claiming the market lead) TNT-MIPS and PCI ENVI 3.0

incorporates substantial new features:

NEW GIS FEATURES

Perform heads up vector digitizing

Build new layers and attributes

Query vector and attribute data

Edit vector layers

Convert raster to vector data

NEW 3D SURFACE VIEWER

Fly over the 3-D surface

Specify a flightpath using image annotation

Interactively read Cursor from 3-D View

NEW SPECTRAL FEATURES

New mixture tuned matching filter for classification

Identify materials with Spectral Analyst

New spectral libraries: soil and vegetation

NEW ORTHO-RECTIFICATION FEATURES


Calculate interior orientation with camera info

Establish exterior orientation using ground control points

Ortho-rectify air-photos or SPOT data

For a complete overview of ENVI and the new features of V3.0, or to order your

evaluation CD-ROM copy and links to other remote sensing sites visit

http://www.floating.co.uk/envi or telephone or e-mail.

Dr Tony Kehoe at ENVI Sales, Floating Point Systems UK Ltd

Ash Court, 23 Rose Street, Wokingham, Berks, UK, RG40 1XS

Tel: 44(0)118 977 6333 Fax: 44(0)118 977 6433

email: [email protected] http://www.floating.co.uk

Don’t take a risk with your image processing….

use ERDAS, ER Mapper, ENVI..or PCI…or….

http://www.floating.co.uk/envi


GRSG MEETINGS

NEW! Annual GRSG Meeting

Research in Progress

Wednesday 18 November, 1998

Oxford-Brookes University

This is intended to be the new GRSG annual meeting slot. It will also be the venue of

the 1998 Annual General Meeting of the GRSG

Contact: Prof. Howard Colley, Tel:01865 483901

email: [email protected] Kelly Davis

Tel: 01865 883641 email: [email protected]

Research Centre, Oxford Brookes University, Gipsy Lane Campus,

Headington, Oxford OX3 0BP, UK

General: Tel: 01865 483600 fax: 01865 483926


OTHER MEETINGS

GEOSCIENCE 98

14 - 18 April 1998

University of Keele, UK

Enquiries: The Conference Department, The Geological Society, Burlington House, Piccadilly, London W1V 0JU.

Tel: +44 (0)171 434 994 Fax: +44 (0)171 439 8975 Email: [email protected]

OPERATIONAL REMOTE SENSING FOR SUSTAINABLE DEVELOPMENT

Preliminary Announcement and Call for Papers (EARSeL/NSEOG):

11 - 15 May, 1998

DISH Hotel, Enschede, The Netherlands

For details: EARSel Secretariat, Madeleine Godefroy, B-318, 2 Avenue Rapp,

F-75340, Paris Cedex 07, France

Tel: +33 1 45 56 73 60 Fax: +33 1 45 56 73 61 Email: [email protected]

EUMETSAT - European Organisation for the Exploitation of Meteorological Satellites

9th Conference on Satellite Meteorology and Oceanography

25 May 1998, Paris, France

To be held at the Hotel Frantour Suffren, 20, rue Jean Rey, 75737 Paris Cedex 15.

More information from:

http://www.onr.navy.mil/sci_tech/ocean/9thsmo


INTERNATIONAL CONFERENCE ON EARTH OBSERVATION DATA IN

FORECASTING, MANAGING AND RECOVERING FROM NATURAL AND

MAN-MADE DISASTERS

3-5 June 1998 London, UK

Contact: Berni-Miles Taylor, Anite Systems, The Gables, Curload,

Stoke St. Gregory, Taunton TA3 6JA, UK

Tel: +44 1823 698175 Fax: +44 1823 698179

Email: [email protected]

27TH INTERNATIONAL SYMPOSIUM ON REMOTE SENSING OF ENVIRONMENT

CALL FOR PAPERS

8 - 12 June, 1998

Tromsø, Norway

Submission of camera ready copy of full paper: 1 April 1998

Papers will be peer-reviewed, on request, for publication in a major international journal

Details: Norwegian Space Centre, P.O. Box 113 Skoyen, N-0212 Oslo, Norway

Tel: +47 22 51 18 01 Email: [email protected] WWW: http://www.spacecentre.no/

5th CIRCUMPOLAR REMOTE SENSING SYMPOSIUM

22-26 June 1998 Dundee, UK

Contact: Sheila Newcombe, Dundee Centre for Coastal Zones Research,

A.P.E.M.E., University of Dundee, DD1 4HN, UK

Tel: +44 1382 344933 Fax: +44 1382 345414 Email:

[email protected]


CONFERENCE ANNOUNCEMENT AND CALL FOR PAPERS

First International Conference on GIS for the 21st Century

Geographical Information Systems in the next Millennium

6 - 8 July 1998, Udine, Italy

Conference Secretariat: Sue Owen, GIS 98, Wessex Institute of Technology, Ashurst Lodge, Ashurst, Southampton, SO40 7AA, UK

Tel: 44 (0) 1703 293223 Fax: 44 (0) 1703 292853


DATA INTEGRATION: SYSTEMS AND TECHNIQUES

13 - 17 July 1998

Cambridge, UK

Contact: ISPRS Commission II Symposium, Prof. I. Dowman, Department of Photogrammetry and Surveying,

University College London, Gower Street, London WC1E 6BT, UK

Tel: +44 171 380 7226 Fax: +44 171 380 0453

email: [email protected]

24TH ANNUAL CONFERENCE AND EXHIBITION OF THE REMOTE SENSING SOCIETY

CALL FOR PAPERS RSS98 Developing International Connections

9 - 11 September, 1998

The University of Greenwich, UK

Submission of camera ready copy of full paper and registration fee: June 1998

Contact: Ian Downey, Medway Campus, Pembroke,

Chatham Maritime, Kent ME4 4AW

Tel: +44 (0)181 331 9803 Fax: +44 (0)181 331 9805

Email: [email protected] http://www/gre.ac.uk/~rss98


19TH ASIAN CONFERENCE ON REMOTE SENSING

16 - 20 November 1998

Manila, Philippines

For further information contact: Ms Chiwako Fujino:


Also see: http://www.geog.nottingham.ac.uk/rss/rss_m98d.htm#nov98

(The following week is the Euro-Asian Space Week in Singapore, 23 - 27 November

"Co-operation in space: where East and West finally meet”)

ADVANCE ANNOUNCEMENT

XIX ISPRS Congress and Exhibition “Geoinformation for All”

16 - 23 July 2000

Amsterdam, Netherlands

The Netherlands Society for Earth Observation and Geoinformatics (NSEOG) is organising the 19th ISPRS Congress and Exhibition in the year 2000.

The 19th ISPRS Congress and Exhibition with the theme Geoinformation for All will be organised at the RAI International Exhibition and Congress Center in Amsterdam. Venue dates for the congress are Sunday, July 16, 2000 until Sunday, July 23, 2000. The main body of the congress will be preceded by tutorials (to be organised on location) on Friday, July 14, 2000 and Saturday, July 15, 2000 and followed by in-depth workshops starting Monday, July 24, 2000 and ending Wednesday, July 26, 2000. A homepage with information about the 19th ISPRS Congress and Exhibition is presently under construction and should be operational by autumn 1997. For more information about the XIX ISPRS Congress, please contact:

Prof. Dr. Klaas-Jan Beek (Congress director) or

Dr. Freek van der Meer (Secretary),

ITC, Hengelosestraat 99, P.O. Box 6, 7500 AA Enschede, Netherlands

Fax: +31 53 4874400 Email: [email protected]


Mineral Deposits Studies Group Joint Meeting

Abstracts from the MDSG - Annual Joint Meeting

School of Earth and Environmental Sciences, Greenwich University, 5-6 January

1998

The joint session for GRSG research in progress and Annual Meeting of the Mineral

Deposit Studies Group was held at Greenwich in January. Alistair Lamb gave the

keynote speech on January 5th, for the Remote Sensing and Mineral Exploration

afternoon session. The following are selected abstracts from the two-day MDSG

programme:

Status of Remote Sensing within the Mineral Exploration Industry.

Alistair D. Lamb Rio Tinto Mining and Exploration, 4 The Broadway, Newbury,

RG14 IBA, UK

Remotely sensed imagery provides what is essentially a mapping tool, for both

structure and lithology, at various scales of study. The multispectral character of

many data sets adds the extra dimension of mineral discrimination, of value in

developing targets and focusing the efforts of field staff.

Past (the Landsat MSS era)

Geological remote sensing has its origins in aerial photography and photogeology

themselves still very much in use. The availability of digital image data since

Landsat- 1 in 1972 has given rise to the matching computing discipline of digital

image processing. Data from the Landsat Multispectral Scanner instrument gave us

the regional synoptic view for structural mapping, but limited spectral content. Data

over this period was probably oversold, particularly with respect to 'lineaments'.

Nevertheless, many mining companies started up in-house remote sensing


departments with early examples of image processing systems from the early 1980's,

based around a team of photogeologists. The maximum mapping scale of 1:200,000

limited the impact of the data to regional assessments only, with the major emphasis

being on structural interpretation, though some enhancement of iron oxides was

possible.

Present (the Landsat TM era)

Landsat-4 in 1982 carried an improved instrument called the Thematic Mapper, with

better spatial resolution providing mapping scales down to 1:50,000, with more

spectral bands including coverage in the shortwave infrared (SWIR). TM was again

NOT designed with geology being particularly in mind, but has been the workhorse

of the mineral exploration industry over the last decade or more, through its ability to

map 'clay'-rich materials as well as iron oxides. The system is therefore able to detect

outcropping or subcropping hydrothermal alteration systems in felsic environments,

and has enjoyed huge semi-regional application in the and - semi-arid parts of the

world, e.g. Andean South America.

TM data can be complemented by higher spatial resolution data from the French

SPOT system (available since 1986), particularly the 10m resolution panchromatic

product over a 60km x 60km area with optional stereo - re-emphasising the ongoing

photogeological aspect. Imagery is frequently digitally combined with other

exploration data sets through a GIS-style approach, e.g. aeromagnetic data.

The 1990's have also seen the development of comparatively cheap image processing

software running on PC's, and increasing levels of 'outsourcing' of remote sensing

support, to the point where geological remote sensing constitutes quite a 'cottage

industry'. In parallel, the emphasis in-house is becoming less 'remote' with the take-

up of handheld field spectrometers, more as mineral mapping tools in their own right

than as a means of ground-truthing a satellite-derived spectral anomaly.

However, recent industry cutbacks are forcing a re-appraisal of in-house specialist

skills and the value of technology in general. Remote sensing has been given very

little credit for contributing to tangible exploration success, and is perhaps is at odds

with a 'back to basics' message that is now permeating industry. There is a view that


remote sensing has done enough to stay alive in the minerals industry, but still trails

behind geophysics and geochemistry and has not yet unequivocally been seen as a

major contributor to significant discoveries. To counter this view, positive case

histories never are published and much research is done on a confidential contract

basis. No technique in isolation will find an orebody. Other techniques also throw up

false anomalies. TM data is 15 years old and cannot offer any new capability or

leverage beyond the structural mapping and 'broad-brush' hydrothermal anomaly

mapping we have found valuable at semi-regional scales. Furthermore, some

companies have recently invested in in-house airborne facilities, suggesting that the

successes are there but remain discrete.

So, what is required to develop remote sensing in mineral exploration, with the

proviso that many future discoveries will be under cover, or obscured by vegetation?

There is clearly an instrumentation gap between Landsat TM and the field

spectrometer, both in spatial resolution terms (we need drill-target level topographic

detail) and in achieving more informative mineral species maps (not simply 'clay-

rich' or 'clay-poor'). For example, TM cannot detect alteration systems in mafic or

ultramafic environments. Although aircraft systems have been available

commercially for many years, offering more spectral-bands and the ability to map

more minerals than Landsat TM, they have not been taken up with enthusiasm.

One reason is that we have not necessarily known what mineralogy we wanted to

map. Spectrometry cannot directly identify the economic minerals we seek except

through some surrogate signature. The relationship between economic mineralisation

and surrogate host mineral changes is poorly known (and often unique from orebody

to orebody). Fundamentally, the host mineralogy context of deposit settings is in its

infancy.

This means the knowledge base now being made possible by use of high signal-to-

noise field spectrometers is very important. A ground-based spectral orientation

survey provides mineralogical variation and important trends for the project

geologist. It could be as subtle as a 20nm shift in the wavelength of a mica signature,


indicating a regional background mica versus a hydrothermally overprinted mica with

a different internal chemistry. Can this be mapped from the air or from Space?

The future (the „hyper' era)

The late 90's will give us operational data to take us beyond the TM era and address

some of these challenges. One of the research outcomes in recent years has been the

appreciation of the importance of instrument signal/noise ratio in discriminating

surface mineralogy, pointing towards a new generation of systems pioneered by the

NASA 'AVIRIS' instrument.

High spatial resolution systems ('hyperspatial') collecting stereo panchromatic

imagery to pixel sizes of lm are expected during 1998. This will re-emphasise photo-

interpretation as a discipline, somewhat overlooked in recent years with all the

attention having been on spectral enhancement. lm data, if cheap enough, will

supplant aerial photography for many district-scale topographic mapping needs.

One such satellite system (Orbview-3) will also carry an imaging spectrometer at 8m

spatial resolution. The Australian ARIES initiative aims to launch and operate a 100

channel imaging spectrometer by 2001. These 'hyperspectral' systems will offer

mineral species maps of direct relevance to ore deposit detection in appropriate

Geological settings and climatic regimes.

Of particular note is a joint initiative between Australia's CSIRO and World

Geoscience, the geophysical contractor. This will build an airborne profiling

instrument (as opposed to an imaging system) for testing in mid-98, to accompany an

airborne geophysics package. This will collect very high signal-to-noise reflectance

spectra with a 10m pixel, under the flight line of the aircraft, concurrently with

gamma ray and magnetic data, all data being collocated by differential GPS. Mineral

abundance maps will be gridded up from the raw line data as with any other

geophysical data set, with the emphasis on cost per line km and commercial

imperatives.

More than ever, remote sensing and mineral mapping practitioners must be seen as

explorationists, not data processors. The geology, not the technology, must come

first. The true challenge is to understand the host mineralogical expression of ore


deposits and to add incremental, tangible value to field projects on a proactive basis,

over appropriate time scales.

Airborne Multi- and Hyperspectral Data as Applied to Mineral

Exploration in Australia and South America

R.A. Agar, Australian Geological & Remote Sensing Services Perth,

Western Australia

Spectral remote sensing data as applied to mineral exploration traditionally involves

the use of satellite imagery, typically Landsat TM data. This provides a regional

geological and structural overview in support of area selection, with, in some cases,

the added bonus of target selection where clay-iron enrichment is indicated by the use

of standard TM band ratios. Satellite data, although being low cost with substantial

coverage, is limited in both spatial and spectral resolution. In both the relatively flat

lying, easily accessible Archaean terrain of Western Australia and the rugged, often

inaccessible, Peruvian Andes, is not necessarily effective, even as a reconnaissance

exploration tool.

Airborne spectral remote sensing has been around now for over 12 years but has only

recently come of age as far as its ability to provide true value to the mineral explorer

is concerned. This has come about largely because of the advent of high-powered

PCs and sophisticated image processing software. The spatial and spectral resolution

of airborne instruments has long been known to offer significant advantages over

satellite systems. However, the difficulty in georeferencing the distorted airborne data

and reducing its large volumes to produce scaled maps of geological or mineralogical

information capable of integration with other data sets has held back the widespread

application of the technology to mineral exploration. Furthermore, a perceived high

cost has prejudiced the technology as an elective alternative to more traditional

exploration techniques.

However, the availability of archival Geoscan data in Australia is now being used in

an innovative way to provide both reconnaissance and ongoing advanced exploration

support at costs which are more than competitive with alternative approaches to an

inherent deep weathering problem which has hitherto restricted the application of any


form of remote sensing. Western Australia is an and terrain, which would be ideally

suited to geological remote sensing were it not that bedrock geology has been

modified by prolonged tropical weathering to produce a deep lateritic profile which is

now itself in various stages of erosion or burial. Thus, even Landsat TM data has

little impact in trying to map bedrock geology and exploration has traditionally

resorted to geochemical methods of outlining prospective target areas.

In recent years however, detailed research into weathering processes has developed

an understanding of metal ion movements within the deep weathering profile and has

focussed attention upon the need for regolith mapping as a framework upon which to

base exploration geochemistry. Spectral remote sensing has a significant role to play

in regolith mapping and Landsat TM has begun to be widely used. However, it is

limited to providing interpretive regolith maps at 1:50,000 scale at best in areas

where 1:10,000 is needed.

Archival Geoscan AMSS data flown in the late 1980's and early 1990's offers a high

resolution alternative that is finding increasing use not only as a tool for regolith

mapping but also, in exploration targeting. The data is processed to produce indices

of iron oxide, clay, carbonate and silica content which are then draped either

individually or as RGB algorithms over greyscale albedo or DEM's for regolith and

landform analysis. The same indices can also be used to identify hydrothermal

alteration in erosional terrain and residual alteration minerals in transported

overburden to generate exploration targets.

In the Peruvian Andes, Landsat TM has been widely used as a ground selection and

targeting tool based upon its ability to identify clay-iron anomalies using band ratios.

However, it cannot distinguish hypogene clay-iron alteration from supergene, in

some cases generating false targets and in many cases, highlighting very extensive

alteration zones while in others it does not pick up the alteration at all. GER DAIS-63

data was acquired over a large part of the Central Peruvian Andes with the specific

aims of ranking existing targets by analysis of alteration styles and mineralogy, as

well as generating new prospects. Simple difference imaging over the region as a

whole using algorithms designed to enhance argillic, silicic and ferruginous alteration

identified all known prospects as well as new ones. These targets were then further


analysed and their specific alteration styles characterised. Spectral feature fitting and

linear unmixing techniques were used in combination to develop mineral assemblage

maps for prospects and thus rank them according to known exploration models,

resulting in the discovery of gold mineralisation within 10km of an operating mine

and within one of the more heavily explored parts of the district.

Thus, airborne multi- and hyperspectral data are being successfully applied to resolve

exploration problems in very contrasting geological and topographic regimes.

However, the same principles are being applied in each case and the data are proving

their advantage in both spatial and spectral resolution over Landsat. More

importantly, however, the data are also proving to be cost effective in each case when

the costs are compared to alternative exploration approaches.

An Analysis of Mineral Exploration Programmes in Fiji

Howard Colley Geology and Cartography Division Oxford Brookes

University, Oxford

Analysis of 38 exploration programmes carried out in Fiji between 1976 and 1990

reveals a heavy reliance on geochemical prospecting. Principal targets in the

exploration programmes were deposits of epithermal gold and volcanic massive

sulfides. Early stages in the exploration were characterised by collection of rock chip

samples and stream sediments; panned concentrates were also collected in around

half the exploration programmes. Historically panning has been very successful and

all Fiji's major gold occurrences were discovered by this method. Follow-up soil

geochemical surveys were conducted in 70% of the licences along surveyed grids and

in pits and trenches. Channel sampling of rock was also common at this stage. Of

twelve programmes progressing to the drilling, stage five had targets solely defined

by geochemical prospecting.

Geophysical exploration methods, principally magnetic, electromagnetic (EM) and

induced polarisation (IP) surveys, were employed in about 30% of the programmes,

usually at an advanced stage of exploration and commonly after drilling had

commenced. Interpretation of EM and IP results was hampered by tropical-


weathering clays giving long decay times which masked potential sulfide responses.

The limited efficacy of geophysical methods led to a much greater reliance on

geochemistry and geological mapping to define drill targets. Remote sensing has

been employed mainly in the search for eroded volcanic centres.

In all the exploration programmes significant areas of hydrothermal alteration were

located indicating that in volcanic terrain such alteration is the norm around volcanic

centres. Of the 38 programmes, two (Tuvatu and Mt Kasi) have progressed to the

mining or mine feasibility stage. The analysis indicates that the biggest challenge

facing exploration geologists is not to locate areas of hydrothermal alteration and

sulfide mineralisation, but to devise methods that can differentiate productive ground

from barren hydrothermal ground in volcanic centres.

Do We Need ARIES (in Space)?

W.P. Loughlin Geological Consultants (Ireland) Ltd., Derrygonnelly, County

Fermanagh, N. Ireland

"ARIES is the Australian Resource Information and Environment Satellite. The

ARIES project aims to design, build and launch a Low Earth Orbit (LEO) satellite

which will carry into space a hyperspectral sensor capable of identifying materials on

the earth's surface not able to be seen by any current satellites. The hyperspectral

sensor will image the earth using reflected visible and infrared light. ARIES, being a

LEO satellite, will be able to cover the globe and will provide its data commercially

to an international remote sensing market place.

The ARIES-1 project not only involves the development of a satellite carrying a

hyperspectral imaging spectrometer but will be a commercially oriented end-to-end

information system designed to acquire, process and deliver data and value-added

products. The project is firmly based on applications solutions rather than

technological path finding

All of which just sounds too good to be true. Considering that it took some six years

after launch before Landsat TM began to be either useful to, or accepted by, the


mineral exploration community. So how long will it take the same people to support

or accept ARIES?

There can be little doubt that TM is the space-borne imagery of choice for us

prospectors. Discoveries have been made with TM which in total probably exceed

the value of the original satellite. In an ideal world, with good exploration budgets,

the way to do 'Remote Sensing' is to find prospective zones using TM, then overfly

these with airborne scanners, buy the available air photo coverage, integrate the

interpretation of these with previous geological mapping, airmag, geochemistry and

whatever else is available.

This is not an ideal world; we don't have those luxuries, budgets are tight. In most

instances, the airborne scanner route is unnecessary. Follow up your TM anomalies

with FIELDWORK; that means a geologist on the ground, taking rock chip samples,

soils, BLEGS, whatever is needed in the circumstances. One can even do great work

at Alteration Mapping with a hand held spectrometer (PIMA). Not only that but TM

is getting to be extremely cheap these days with big discounts on ten-year-old

imagery.

Therefore, these Australians propose to put up a 30-metre spatial resolution (same as

TM) hyperspectral satellite to cover the earth‟s entire surface. When we already know

that 30 metre is inadequate to map tight vein systems; when we know that it is very

difficult to keep airborne hyperspectral systems well tuned and working on airborne

platforms; when previous efforts at dividing the 'clay band' region were a disaster,

known, but not acknowledged by the academic research community (got to think of

research funding) before launch in the case of the Japanese JERS-1; due to launch or

deployment failure in the case of Landsat 6 or LEWIS respectively).

Although the promoters of ARIES claim that it will be applicable in terrain with up

to 50% vegetation cover, it is undeniable that it will have little application in

vegetated terrain. It will be unsuitable for Africa (with the possible exception of the

Ethiopian Rift - but even there the anomalies have already been found with TM and

extensive fieldwork is underway); Brazil and other jungle parts of S America, the


Pacific Rim. Geological applications in temperate/agricultural parts of Europe?

Forget it.

In mature exploration provinces, the marketable value of ARIES seems even

gloomier. Nevada has two superlative mineral belts, the Carlin trend and Battle

Mountain - Eureka trend, plus some additional prospective areas besides. Most of

these areas have been covered by airborne TM or Geoscan imagery, a lot of which is

in the public domain and by truly hyperspectral imagery such as AVIRIS. Privately

flown GER imagery also covers numerous prospective belts. This airborne imagery is

at really useful spatial resolutions like 7.5 or 10 metre (that's 9 times better than

Landsat) and doesn't have to image through the entire atmosphere.

So how can the ARIES project benefit us prospectors?

The project is led by the best in the business, Jonathan Huntington of CSIRO. To

quote again from the promotional publicity material:- "The project is firmly based on

applications solutions rather than technological path-finding with the development of

specialised value-added products as part of the business strategy."

The project is supported by mining companies. To test and simulate the data airborne

imagery will be flown, and new airborne scanners/simulators will be developed. The

world's leading experts will develop algorithms to get value from the simulated

imagery. At the end of the day, the data (with multi-spectral VNIR bands) will

benefit the agricultural/landuse communities (land degradation, pollution-monitoring

etc.). It might well fly and we prospectors will reap the benefits in the end.

When a few people heard that I was to give a talk on this subject, they automatically

assumed that I would be against ARIES. Not true, I'm all for it, especially the

feasibility and research stages of the project. If it flies - that's a big bonus!.

Mind you I would be more in favour of putting up a dirt cheap multi-temporal single-

band thermal imager, for which the technology exists and is well tested (there are

military versions up there already). To give bulk compositional (as opposed to

'geodermatological') soil/rock properties, applicable in mineral exploration, but more

especially in hydrological work. To help feed people in sub-Saharan Africa (and

other places) where ARIES will be inapplicable.


In the meantime we should wholeheartedly support the ARIES project. It can be

followed on the web starting at: www.cossa.csiro.au/

Spectral geology at the British Geological Survey

S. H. Marsh and A. M. Denniss British Geological Survey, Kingsley Dunham

Centre, Keyworth, Nottingham, NG12 5GG, U.K.

The British Geological Survey (BGS) first became involved in spectral geology

through a standard route; the use of Landsat Thematic Mapper (TM) band 7

anomalies to target clay alteration haloes around precious mineral deposits. Early

work in the Peruvian Andes was funded by the Overseas Development

Administration (now the Department for International Development) and proved very

successful. Techniques employed at that time included standard band ratioing and

principal components analysis.

In recent times this work has been developed in three ways. Firstly, the focus of the

targeting has changed to the clay minerals themselves, in a project looking for bulk

industrial minerals in Sinai, Egypt. Secondly, the techniques employed have become

more sophisticated. Algorithms are now employed which convert the satellite data to

near-reflectance values and the data are analysed in the form of spectra. Finally, new

data sets with more spectral bands have become available, such as those from the

Japanese Earth Resources Satellite JERS-1.

This paper will illustrate these developments with examples from BGS work in Sinai,

demonstrating the range of minerals that can now be discriminated using widely

available satellite data sets. It will also consider what improvements can be expected

following the launch in 1998 of the Advanced Spaceborne Thermal Emission and

Reflectance Radiometer (ASTER). Finally, some examples will be presented of the

use of the Portable Infrared Mineral Analyser (PIMA) in identifying the mineralogy

of core samples.

POSTER PRESENTATIONS

Digital photogrammetry, computer-assisted terrain visualisation

and geological image interpretation


M.A. Bussell School of Earth and Environmental Sciences, University of

Greenwich, Chatham Maritime, Kent ME4 4AW, U.K.

Traditionally stereoscopic interpretation of vertical aerial photographs has provided a

prime tool for the exploration of inaccessible terrain. The principal shortcoming of

this technique is the fixed vertical nature of the viewpoint. The optimum potential of

three-dimensional visualisation of geological structures is often achieved by strategic

viewpoints, for example along the trend of oversteps at an unconformity, fault-vein

intersections and fold axes. Such viewpoints are most uncommon in vertical stereo-

pairs and when they do occur they are fortuitous. A more trivial problem is the

intractable nature of the large number of paper prints needed for any regional study.

A costly and sometimes dangerous solution is use light planes or helicopters, a

cheaper and safer alternative is to use the commonly extant aerial photographic

archive in conjunction with digital photogrammetry. Soon aerial photographic

resolution will be available from space, extending these techniques to regions

without photographic archives.

Digital photogrammetry provides a set of procedures for the generation of digital

orthoimages and digital elevation models (DEMs). An orthoimage can be produced

for the overlap area of two vertical aerial photographs, which have been scanned. The

map grid co-ordinates of ground control points must be known and they must be

carefully identified on both images. It is also desirable to identify a larger number of

matching points of known height. These data can come from published large-scale

maps but high quality global positioning system data is to be preferred. With this

information supplied by the user, image-processing software is used to automatically

match features, pixel by pixel, on each digital image and correctly solve

photogrammetric equations to give the true location and height of each point.

There are two outputs from this process. First a digital elevation model (DEM is

produced: a raster array of height values mosaiced to cover the region of interest.

Because the DEM is a model of the surface seen on the aerial photograph, it will

include buildings, trees and continuous canopy surfaces. In such cases a certain

amount of editing is necessary if a model of ground heights is required. These effects

are minimal in poorly vegetated semiarid areas and acceptable DEMs for


visualisation purposes are fairly easy to produce. The second output is a digital

orthoimage which is similarly a mosaic of the region, when printed, has all the

appearance of a normal aerial photograph. The difference is that all radial relief

distortions have been removed, scale is constant in all directions and a map co-

ordinate grid can be placed on the image. If the aerial photography is in colour then

the orthoimage can be manipulated by methods chosen from an array of routine

image processing techniques in order to enhance geological features.

These techniques can be applied to terrestrial and aerial stereo-pairs and the outputs

used to assist in terrain visualisation and geological interpretation. The DEM can be

used by appropriate software to generate a perspective model of the terrain, the

orthoimage can then be draped over this model and inspected from any desired angle

in order to help clarify details of a geological interpretation. Because the DEM and

orthoimage are mosaics produced from a large number of overlapping photographs

they can be inspected continuously by "fly through" methods giving maximum

flexibility in three dimensional visualisation of the dataset. Examples are presented

show how the techniques can be used to help recognise progressive overstep at an

unconformity, facies transitions the orientation of fold axes and the geometry of

faults and veins.

Remote lithological identification via spectral differentiation of an

area adjacent to Loch Assynt, NW Scotland, using ERDAS Imagine

David Holmes School of Earth & Environmental Sciences, University of

Greenwich

The purpose of this study is to test how far it is possible to use vegetation cover to

identify bedrock geology. The study area includes a 9km2 section of the Assynt

district, Sutherland. The elevation of the area ranges between 80-350m above sea

level. The area consists of Lewisian gneisses, Torridonian red beds and a succession

of Cambro-Ordovician quartzites, siltstones and limestones, which were stacked into

a pile of thrust nappes during the Caledonian orogeny.


Saraf et al (1989) used the Airborne Thematic Mapper with eleven separate bands to

complete a botanical study of an area approximately 10km south of Loch Assynt.

Their data were used to detect vegetation stress in relation to underlying mineral

deposits. Biomass characteristics were recognised between plant type and in the

change of spectral response between bands. Study area spectral discrimination was

achieved via comparison of reflectance of south facing slopes in a range of Landsat

TM bandwidths (1-7). This was possible with pre and post fieldwork analysis via use

of ERDAS Imagine 8.2.

Initial project processing saw the georectification and gridding of the region using a

SPOT Panchromatic image. Post fieldwork processing involved the georectification

and 1:25000 gridding (from OS maps) of the project area, using a Landsat TM image.

This resulted in a series of bandwidth triplet options to identify geobotanical species.

Two were found to be non-discriminatory. Plant type discrimination was due to a

difference in reflectance. Plants with greater H2O content were more easily discerned.

Detailed spectral analysis using the built-in ERDAS Imagine 8.2 library enabled

identification of the sub-surface lithologies. Due to the resolution of the Landsat TM

data collection systems, this is only reliable to a 30m minimum.

The geology around Beinn an Dubhaich, Isle of Skye, as determined

using Landsat TM imagery and field mapping

Barbara Morgan School of Earth & Environmental Sciences, University of

Greenwich, Chatham Maritime, Kent ME4 4AW, U.K.

The area around Beinn an Dubhaich in southeastern Skye is dominated by a large

granitic intrusion that cuts older Cambro-Ordovician carbonates. The form and mode

of intrusion of this granite body is controversial, and an investigation of the outcrop

pattern and shape of the intrusion forms the basis of this work. One of the principal

aims of the project was to assess the comparison that can be made between the

resulting solid geology map and processed satellite images.

Prior to fieldwork, a Landsat TM satellite image of the project area was processed

using ER Mapper 5.2 and ERDAS Imagine 8.2 software. The outcrop pattern of the


Beinn an Dubhaich Granite determined using Red-Green-Blue (RGB) and False

Colour composites along with various ratio images (e.g. vegetation, clay and iron

oxide). Each of these was then compared with the mapped granite outline in an

attempt to establish the "best fit' between the situation established on the ground and

the sensed image. The best results were obtained using the vegetation index, False

Colour and RGB images.

GRSG’ Committee’s Spring Outing………?


FEATURE

Could the Grand Canyon Village area become part of a future

landslide block? Some observations from remote sensing

data.

While viewing a SEASAT radar image over the area of the South Rim, I noticed a

curved escarpment east of the village area that was oriented concave toward the

north. Figure 1, from Avery and Berlin (1992), shows this SEASAT radar image

with the curved escarpment denoted by the lower two arrows. The third arrow, bear

the top of the image, point to the Grand Canyon National Park Airport runways,

which are on a trend with the Vishnu Fault zone. I wondered if this represented the

geomorphic expression of the early stage of a future slump block or rotational

landslide. Could the Grand Canyon Village area or other areas along the South Rim

become part of a future landslide block?

Figure 2, from Avery and Berlin (1992) shows an airborne radar image along the

South Rim of the Grand Canyon, North is toward the bottom of this image. The

Bright Angel Fault can be seen trending from A to A‟ with A‟ being over the area of

the Grand Canyon Village on the South Rim. A curved linear feature, delineated by

two arrows, can be observed trending approximately parallel to the South Rim at this

location. Does this also represent the geomorphic expression of a future slump block

or rotational landslide, or a palaeo-fault, or neither?

Landslides are just nature‟s way of responding to donwcutting and erosion to try to

reach a state of equilibrium. This process occurs on a daily basis in the Grand

Canyon usually on a small scale. This author can recall many backpacking trips along

the Tonto Trail on rainy Spring days suddenly hearing the crack of breaking rock

followed by low rumble of the broken cliff face pieces tumbling down the South Rim

slopes. On some river trips, we would find that our campsite from the previous year


was now covered in rubble. Usually the detachment layer is a ductile unit such as

shale overlain by more competent, or harder, rock such as limestone or sandstone.

Larger scale landslides may occur as the river cuts into the shale units causing the

lateral support to be removed, with the shale wanting to „flow‟ toward the newly

created gap. As moisture percolates down into the shale through fractures from the

rocks above, or by saturation from river water, the shale becomes lubricated and may

swell forming a detachment plane. So, the „rug‟ is pulled out from under the cliff-

forming rocks above, causing slope failure and landslides.

A large landslide did occur in the Surprise Valley area along the north side of the

Colorado River, west of Thunder River. Quoting Ford and others, in Breed and Roat

(1976), “the is the most spectacular example of landsliding in the Grand Canyon. The

debris that comprises the slide occupies between 3 and 4 square miles of terrain north

of the Colorado River and extends for 4.5 miles. The maximum width of disturbance

is over 1.5 miles in Surprise Valley.”

A cross-section of this rotational slide block can be seen in Figure 5, from Huntoon,

in Breed and Roat (1976). This shows the Redwall Formation and Supai Group

rotating into the fault plane and gliding along a detachment in the Bright Angel

Shale. It is felt that this occurred after the Colorado River cut through the Bright

Angel Shale, which then lost support and became saturated. Similar landslide

features can also be seen in other areas of the Colorado Plateau.

Finally, to gain an overview of the Grand Canyon area. Figure 6 shows a Landsat

MSS scene covering an area of approximately 110 miles on side. The San Francisco

Peaks and volcanic field as well as Flagstaff can be observed in the lower right corner

of this image. The arrow, in the centre of the scene, points northeast along the trend

of the Bright Angel Fault heading into the Grand Canyon Village area. The side of

the canyon originating just to the northwest of the arrow is Havasu Canyon.

On this image, the Kailab Plateau can be observed as the large northwest trending oval in the centre of

this scene. The Paiute word „Kaibab‟ is translated as „mountain lying down‟. If this uplift was not

present for the Colorado River to flow through, the Grand Canyon would have been no more

spectacular than the Little Colorado River gorge which can be seen in this figure entering the Canyon

from the east.


One other observation that can be made from this image is that the area of dissection

and erosion north of the Colorado River is wider than the dissected area south of the

River. This is due to the southerly dip of the rocks along the south plunge of the

Kaibab Upwarp causing ground water to flow toward the south. This explains the

larger and more spectacular springs emanating from the North Rim, and why the

South Rim has a problem with ground water retention. Ground water is flowing away

from the South Rim.

So, will the Grand Canyon Village area or other areas along the South Rim have a

geologic future similar to the Surprise Valley landslide? Probably not at the same

scale, and certainly not tomorrow, but in terms of geologic time who knows? As has

occurred in the San Juan Capistrano area of Southern California, a leaking swimming

pool can cause an entire hillside to fail. Therefore, in the Grand Canyon Village area

we should be aware of anything that will saturate the underlying shale. Leaking water

pipelines or irrigation systems could cause such saturation. From a safety and

environmental standpoint we probably do not want to speed up the natural process of

erosion.

It would be interesting to field check the escarpments that I observed and delineated

in Figures 1 and 2. Ground truthing may either disprove or validate my remote

sensing observations. In any event, I hope you have found these observations

informative. The Grand Canyon is a marvelous feature to view, even from outer

space.

By William D. Di Paulo

REFERENCES

Avery, T. E. and Berlin, G. L. 1992. Fundamentals of remote sensing and airphoto

interpretation, Fifth Edition, Macmillan Publishing Company, New York.

Breed, W. J. and Roat, E. 1976. Geology of the Grand Canyon. Museum of North America, Flagstaff.


Figure 1. SEASAT L-band (23.5cm) synthetic aperture radar image acquired in

1978. North is toward the bottom of this satellite image. The spatial resolution of

SEASAT radar data is 25m (from Avery & Berlin, 1992).


Figure 2. Airborne K-band (0.86cm) radar image along the South Rim of the

Grand Canyon. North is toward the bottom of this image (from Avery & Berlin,

1992).

Figure 5. A cartoon depicting the cross-sectional view of the Surprise Valley

landslide (from Huntoon, in Breed and Roat, 1976).


QUESTIONNAIRE

Remote Sensing in UK Geoscience Degrees

Name of person completing questionnaire:

…………………………………………………………………………………………

Email address:

…………………………………………………………………………………………

University Department Degree Title

........................................ .................................... .......................................

1. How long has remote sensing been part of your undergraduate geology

curriculum? ...........Years

2. How many hours of remote sensing teaching are there in the core programme for

your geology students?

Year 1 Year 2 Year 3

lectures .......... .......... ..........

practical .......... .......... ..........

3. How many hours of remote sensing teaching are there in the option programme

for your geology students?


lectures .......... .......... ..........

practical .......... .......... ..........

4. Percentage of remote sensing practical work devoted to:


Photogrammetry .......... .......... ..........

Photogeological Interpretation .......... .......... ..........

Fieldwork .......... .......... ..........


Hands-on Image Processing .......... .......... ..........

Individual Project Work .......... .......... ..........

5. Contribution of remote sensing to final year project fieldwork

.........................................................................................................................................

.........................................................................................................................................

………………………………………………………………………………………….

6. Number of staff with remote sensing as main or joint specialism ……………….

7. Remote sensing inputs from other Departments................................% of

programme

Department of ....................................................

8. Computing facilities available for remote sensing, please give brief indicative

information:

No of PCs. ...................

No of Workstations ...................

Tape drives ...................

Digitisers ...................

Scanners ...................

Hardcopy devices. ...................

Digital Data ...................

Software ...................

Technical support ...................

9. What are the main strengths of your remote sensing teaching?

.........................................................................................................................................

...................…………………………………………………………………………….


.........................................................................................................................................

...................…………………………………………………………………………….

10. What are your aims for the future development of remote sensing in the degree

programme?

.........................................................................................................................................

..................……………………………………………………………………………...

.........................................................................................................................................

....................…………………………………………………………………………….

.................................................................................……………………………………

11. What are the main problems/limiting factors in achieving these aims?

.........................................................................................................................................

.....................……………………………………………………………………………

........................................................................................................…………………….

………………………………………………………………………………………….

………………………………………………………………………………………….

12. Any other comments?

____________________________________________________________________

Please return to Dr Andy Bussell (address inside front cover)

SUMMER COMPETITION


Following the award of the 1997 Summer Competition prize (a field excursion to the

infamous „Kyrzigstan‟), announced in the previous issue of the GRSG Newsletter, to

John Berry of Shell, Houston, we thought we‟d show you a picture of two previous

winners of this prestigious award (having a marvelous time) just to spur you all on in

your endeavors.

Dr J. G. Liu and John McM Moore, of Imperial College, London


DISCLAIMER & MESSAGE FROM PHILIPPA

No responsibility is assumed by the publisher for any injury and/or damage to

persons or property as a matter of product liability, negligence or otherwise, or from

any use or operation of any methods, products, instructions or ideas contained in the

material herein. Although all advertising material is expected to conform to ethical

(medical) standards, inclusion in this publication does not constitute a guarantee or

endorsement of the quality or value of such product or of the claims made by its

manufacturer.

The GRSG does not purport to have a unified view and this newsletter is a forum for

the views of all its members and their colleagues in industry, colleges and

government on a free and equable basis.

Compiled in Microsoft Word for Windows and printed by Triographics Ltd, Knebworth

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