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American Association of Petroleum Geologists International Conference and ExhibitionOctober 15–18, 2000Bali, IndonesiaAbstracts

EVALUATION OF SATELLITE RADAR (SAR) INTERFEROMETRIC COHERENCE IMAGES FOR GEOLOGIC AND LANDCOVER MAPPING, AND COMPARISON WITH LANDSAT TM OPTICAL IMAGERY, SE KALIMANTAN, INDONESIA

Barton, Robert H., and Walter D. Tomlinson, Spectra Resources, Inc., Houston, TX

Optical satellite imagery has been used successfully forgeologic and environmental interpretation and mapping forsometime. However, optical imagery is limited by its inabil-ity to penetrate clouds. Many of the prime exploration areas,such as Indonesia, are found in areas where cloud cover is asignificant barrier to the use of imagery. Satellite SAR oper-ates in wavelengths that allow imaging of perennially cloud-prone areas. However, these SAR images have limitations indiscriminating wide classes of surface attributes and condi-tions. Interferometric processing significantly increases theability to define these features.

This study evaluated the utility of RADAR Coherence im-ages for mapping surface geologic features and landcover/landuse categories. The study compared the features and at-tributes that were mappable from both the optical and Coherenceimages and the variation of signature characteristics for each im-age type. For geologic features, the analysis comprised a quali-tative comparison of the interpretability of each image type,any variations in apparent structural dimensions of mapped fea-tures, and possible discrimination of various surface lithologies.The evaluation of the Coherence imagery for landcover/landusemapping utilized various filtering, image classification, changedetection, and GIS mapping techniques. This study has shownthat RADAR Coherence imagery can be successfully used to aidin geologic and environmental mapping in cloud-covered areas.

OVERVIEW OF THE STATUS OF GEOLOGIC CARBON SEQUESTRATION RESEARCH IN THE U.S.A.

Beecy, David, U.S. Department of Energy, Germantown, MD and Vello Kuuskraa, Advanced Resources International, Arlington, VA

Carbon sequestration is a relatively new field of scienceand technology. However, interest in it has been growingrapidly over the past several years. In 1998, the Office ofFossil Energy and the Office of Science of the Department ofEnergy jointly initiated an activity to develop a roadmap forcarbon sequestration as one new means of addressing cli-mate change concerns. One of the major options is the stor-age of CO

2

in geologic formations. Results of this activity,including a workshop in mid-September 1999, have beenposted on the internet, and the process is continuing.

In parallel, a Carbon Sequestration Research and Devel-opment Program has been evolving in the Office of FossilEnergy, in partnership with industry, other agencies, and theInternational Energy Agency Greenhouse Gas Research andDevelopment Program; and a Carbon Management ScienceProgram has been evolving in the Office of Science.

This paper summarizes the progress and findings to datein both the roadmapping and program planning and devel-opment and provides an indication of future directions. Rec-ommendations include how to obtain additional informationand to join in this global, public/private partnering process.

CHEVRON AND WWF: LESSONS LEARNED FROM SIX YEARS OF COLLABORATION ON BIO-DIVERSITY PROTECTION IN PAPUA NEW GUINEA

Flemming, Dennis, Chevron Niugini Limited, Port Moresby, Papua New Guinea and Dan McCall, World Wildlife Fund, N/A

In 1994, the Kutubu Petroleum Development Project (es-tablished by a consortium of oil companies and operated byChevron Niugini Limited) embarked on a unique partner-ship with the World Wildlife Fund (WWF) to conserve theglobally significant forest ecosystem of the Kikori River catch-ment in Papua New Guinea. The Kutubu Project is Papua NewGuinea’s first petroleum development project and is surrounded

A B S T R A C T S

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by the vast 2.3-million-hectare Kikori River catchment. Thepartnership established between Chevron Niugini and WWFinitiated the Kikori Integrated Conservation and Develop-ment Project (KICDP) to assist the people of the KikoriRiver catchment to conserve their natural resources, whichare under threat primarily from large-scale logging. Al-though few partnerships of this magnitude exist between in-ternational oil companies and conservation organizations,the KICDP has proven that such a partnership can be a suc-cessful way to promote and achieve environmental conser-vation. This partnership is predicated on Chevron Niugini’sefforts to safeguard the environment through environmentalcontrols and WWF’s goal of conserving the earth’s out-standing biological diversity. The KICDP completed its firstthree-year phase of operation in 1997 and initiated a secondthree-year phase in January of 1998 with funding from theGobe and Kutubu Petroleum Development Projects. BothChevron and WWF have recently completed internal re-views of the partnership. This paper describes the results ofthese reviews. The conclusion from six years of partnershipexperience between Chevron and WWF is that this partner-ship—and potentially others like it—offers considerable prom-ise as an innovative strategy for environmental protection.

DEMONSTRATING THE POTENTIAL FOR GEOLOGICAL STORAGE OF CO

2

: THE EUROPEAN SLEIPNER AND GESTCO PROJECTS

Gale, John, IEA Greenhouse Gas Research and Development Program, Cheltenham, United Kingdom

For the European Union (EU) to meet the CO

2

emission re-duction targets set by Kyoto, other options of greenhouse gasmitigation than fuel switching, energy efficiency, and renew-ables will have to be considered. The geological storage of CO

2

from fossil fuel use is a potential option to reduce the im-pact of climate change and assist the EU in meeting itsKyoto targets. Two projects are now underway in the EU tostudy the potential for CO

2

storage and to demonstrate storageCO

2

. The first Project, known as GESTCO, will assess the po-tential CO

2

storage capacity of the main sedimentary basinswithin the EU. GESTCO will examine in detail the geologicalstorage potential and coincidence of CO

2

emission sourcesand potential storage sites.

In the North Sea, the world’s first commercial geologicalstorage project has now been in operation for three years.The Sleipner West field began production in 1996. The nat-ural gas from the Sleipner field contains

z

9% CO

2

, whichmust be reduced to 2.5% before sale. The CO

2

is stripped fromthe natural gas by an amine scrubbing plant and then injectedinto a saline water bearing structure about 800 m below theseabed. To date,

z

3 million tons of CO

2

have been stored.

COAL BED METHANE ENHANCEMENT WITH CO

2

SEQUESTRATION—WORLDWIDE POTENTIAL

Gale, John Joseph, Greenhouse Gas Research and Development Program, Cheltenham, Glos, United Kingdom and Paul Freund, IEA Greenhouse Gas Research and Development Program, Cheltenham, United Kingdom

A new coal bed methane production technology has theadded attraction of tackling greenhouse gas emissions. In-jection of carbon dioxide, an important anthropogenic green-house gas, into deep coal seams can enhance methane recov-ery, whilst simultaneously locking up the carbon dioxide inthe coal measure. Providing the coal is never mined, the car-bon dioxide would be sequestered for many years, andthereby help to avoid climate change.

Initial results from the world’s first carbon dioxide–enhanced coalbed methane (CO

2

-ECBM) pilot in the south-western United States show this new technology to be tech-nically and economically feasible. Since 1996,

.

57 millionm

3

(2 Bcf) of CO

2

has been sequestered in Cretaceous Fruit-land coal seams located in the northern San Juan Basin.Based on current costs and performance, CO

2

-ECBM maybe profitable in the San Juan and nearby basins at prevailingwellhead natural gas prices of US$0.06–$0.07/m

3

($1.75–$2.00/Mcf), representing an estimated 8.5 Gt of CO

2

se-questration potential. The technology for implementing andoperating CO

2

-ECBM recovery is based on demonstratedoilfield technology, although further refinements are needed.Apart from the San Juan basin, coal basins in Australia, Rus-sia, China, India, Indonesia, Canada and other countries alsohave large CO

2

-ECBM potential, estimated at 150 Gt CO

2

.Analysis of representative CO

2

-ECBM projects indicatesthat 5 to 15 Gt of carbon dioxide could conceivably be se-questered at a net profit, while

z

60 Gt of sequestration ca-pacity may be available at moderate costs of

,

$50/ton CO

2

.

ENVIRONMENTAL AND SAFETY CONSCIOUSNESS IN THE OVERLAPPING AREA OF PETROLEUM AND COALMINING INDUSTRY: EAST KALIMANTAN CASE

Hamdani, Achmad, Pertamina - BPPKA, Jakarta, Indonesia; Achmad Nurdin, Exspan Kalimantan, Jakarta, Indonesia and Rochana Hassan, Vico Indonesia, Jakarta, Indonesia

East Kalimantan is one of the richest areas in terms of oil/gas and coal production. Petroleum companies have suc-cessfully developed this area as the second biggest producerin Indonesia for the past few decades. When it was reported

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that the oil/gas reserves will be finished, coal companiescame in to the area. Some of them have successfully pro-duced the coal. Because the authority issued a permit to ex-plore the oil/gas and coal, the existence of an overlappingarea can’t be avoided. However, when coal exploration dis-covered the economic reserve in the petroleum area, theoverlapping area became a serious problem. The exploita-tion of coal mining activities uses an open pit method andwill have negative consequences to the environment andsafety; however, the most critical aspects are shallow re-serves as well as the pipeline nearby the exploitation area.The best solutions for mutual benefits are that the followingsteps are carried out. The mining concession area of Petro-leum companies, in terms of prospect (priority), should bedivided into three categories: red area or exploitation area:where there are wells, pipeline (flow line and trunk line)gathering stations, and other installations. Coal mining ac-tivities in this area are prohibited; yellow area or prospectarea: area under exploration, need time for considering todeclare. The coal mining activities should wait for the ex-ploration result before entering the area; green area or non-prospect area: coal company can exploit the area at anytime. If the oil/gas pipeline and installation or another pro-duction facilities exist, both oil/gas and coal activities shouldhave good coordination. In order to achieve a win–win solution,a Memorandum of Understanding (MOU) should be issuedprior to coal exploitation in the oil/gas prospect area. The valid-ity of MOU is

z

5 years and should be reviewed thereafter.

REDUCTION OF “GREENHOUSE GAS” EMISSIONS THROUGH UNDERGROUND CO

2

SEQUESTRATION IN TEXAS OIL AND GAS RESERVOIRS

Holtz, Mark H., Teknecon Energy Risk Advisors LLC, Austin, TX; David L. Carr, Geoscience Consultant, Austin, TX and Peter K. Nance, Teknecon Energy Risk Advisors LLC, Austin, TX

A promising method for reducing CO

2

emissions—andthus reducing potential human impacts on global climate—is through sequestration of CO

2

in subsurface reservoirs.The greatest concerns regarding the feasibility of subsurfaceCO

2

sequestration are the economics and the long-term trap-ping capability of a given reservoir over geologic time. Us-ing CO

2

emissions in enhanced oil recovery (EOR) opera-tions may provide a solution that addresses both concerns.Oil reservoirs are ideal candidates for CO

2

sequestration be-cause they are proven geologic traps. Structural analysis,caprock evaluation, and pressure monitoring similar to themethods widely used by operators of underground gas-stor-age reservoirs can be applied to oil reservoirs to determinetheir viability for CO

2

sequestration. The economic benefit

from increased oil production resulting from EOR by CO

2

injection would partly, or in some cases, fully offset the costsof power plant CO

2

capture, pipelines, and transportation.CO

2

EOR can produce oil that would otherwise not be re-covered, at an incremental cost of $6–$12 per stock tankbarrel (STB; 1992 U.S. dollars). More than 1700 oil reser-voirs are possible candidates for CO

2

EOR in Texas. Thesereservoirs represent 80 billion STB of original oil in place,of which 31 billion STB is residual oil, the target for CO

2

EOR. Eight billion STB of this resource is within a 90-mileradius of candidate coal or lignite fired plants in Texas. Inaddition, between 12 and 20 years of CO

2

production from19 lignite or coal fired boilers could be sequestered.

SUBSURFACE CO

2

DISPOSAL WITH ENHANCED GAS RECOVERY AND BIOGEOCHEMICAL CARBON RECYCLING

Koide, Hitoshi, Research Institute of Innovative Technology for the Earth, Tokyo, Japan and Kenichi Yamazaki, Mitsui Mining Engineering Co., Ltd, Tokyo, Japan

There is an enormous amount of methane in subsurfaceformations in the world. Most of the natural gas resources,however, is hardly economically recoverable as the methaneis adsorbed in coal seams, trapped in hydrate clathrate, ordissolved in saline groundwater. Shallow accumulation ofmethane is even a hidden threat of explosive global warming.Enhanced gas recovery by subsurface CO

2

injection (CO

2

-EGR) is a practicable solution for the greenhouse gas controlwith efficient use of potential energy resources. Extremelylight isotopic compositions of carbon in methane suggest thatmethanogens formed many subsurface accumulations of meth-ane-rich natural gas in the world. Chemolithotrophic methano-gens, that belong to Archaea, form methane from CO

2

and gainenergy without sunlight in anoxic circumstances. Methanogensare often blamed for greenhouse gas emission as they producemethane in bowels of cows and termites and in rice paddies.However, reapplication of CO

2

-EGR for subsurface biogenicmethane that is converted from disposed CO

2

makes the car-bon recycling possible. Subsurface ecosystem is somewhatsimilar to archaic ecosystem that is adapted to anoxic CO

2

-rich atmosphere under high pressure and temperature. Bionicmethanogenesis is active even in deep basaltic aquifers. Sub-surface biogeochemical carbon recycling may realize green-house gas control with restoration of energy resources.

SOURCE, MIGRATION AND CO

2

OCCURRENCES IN THE PAILIN FIELD, GULF OF THAILAND

Martens, David, Rui Lin, and Robert Hickman,Unocal Thailand, Ltd, Bangkok, Thailand

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73

The Pattani Trough is an extensive Tertiary rift-sag basinin the Gulf of Thailand where several large gas fields havebeen discovered and developed since 1979. The structure inthe main producing interval (Miocene) of the Pattani Troughis dominated by a series of highly faulted half-grabens or“graben complexes.” During the Oligocene, lacustrine depo-sition dominated in the basin (secondary source) followed byfluvial deposition in the Miocene and Pliocene (primary res-ervoir, source, and seal). Pailin Field, representing one ofthe half-graben systems, is located in the southern PattaniTrough. The field’s petroleum system involves two distinc-tive hydrocarbon sources: a fluvial coaly facies and a lacus-trine shale facies. Gas condensates from the lacustrine fa-cies are characterized by low pristane/phytane ratios andhigh gammacerane, whereas those from the fluvial sourcesare characterized by high pristane/phytane ratios and highangiosperm resin markers (bicadinane “W” and bicadinane“T”). The lacustrine sources are deeply buried and overlainby high sand/shale ratio alluvial deposits, permitting verti-cal migration along fault planes and/or stacked sands. Incontrast, the majority of the hydrocarbons in the field weresourced locally from Middle Miocene fluvial coals and car-bonaceous shales. Hydrocarbon migration from the coalyfacies was predominantly lateral; the migration model inconjunction with the thermal maturity analysis allows foraccurate pay window predictions. The Pailin gas containsappreciable amounts of CO

2

(5 to over 65%) derived fromboth organic and inorganic sources, which can be predictedpre-drill through a relationship between CO

2

partial pres-sure and temperature or depth. This understanding of source,migration and CO

2

distribution facilitates the developmentand production of Pailin Field.

UTILIZATION OF METHANE AND INJECTION OF CARBON DIOXIDE INTO ABANDONED COAL MINES

Ohga, Kotaro and Kiyoshi Higuchi,Hokkaido University, Sapporo, Japan

Ishikari coal field is the most gassy coal field in Japan.There is no operating coal mine in this coal field. But thereare many abandoned coal mines in the coal field. Fromthese abandoned coal mines, methane has emitted into theatmosphere. This is a significant problem for global warm-ing. Therefore, we have planned to use the methane emittedfrom the abandoned coal mines for small-scale generatorand inject the exhaust generated by the engines for electricgeneration into the gob area of the abandoned coal mines.Injected carbon dioxide into the abandoned coal mines isabsorbed by coal remaining in the gob area and replacesmethane absorbed by coal. In order to make it clear, dis-placement tests of methane by carbon dioxide were carried

out at the lower pressure (

,

2 atm.). In this paper, the resultsof the tests and outline of this project are described.

THE GEODISC PROGRAM: RESEARCH INTO GEOLOGICAL SEQUESTRATION OF CO2 IN AUSTRALIA

Rigg, Andy, Australian Petroleum Cooperative Research Centre, Sydney, NSW, Australia and John Bradshaw, AGSO, Canberra, ACT, Australia

In Australia, some of the largest point-source emitters ofCO

2

are LNG plants and it is projected that emissions willincrease as Australia develops more fields for LNG, someof which have higher CO

2

content than currently producingfields. The GEODISC research program, funded by the Aus-tralian Government and some of the nation’s gas producers, isdesigned to address key technical, commercial, and environ-mental issues associated with geological sequestration in Aus-tralia and is predicted to take four years to complete. It is an-ticipated that the results of the research will have applicationboth within Australia and internationally.

The first phase of this program is the identification ofthose geological formations in each sedimentary basin withthe most appropriate parameters to sequester large volumesof CO

2

. The parameters will not only be the physical char-acteristics for both the target reservoir and seal formations,but also the temperature, structural setting, stress regime,and hydrogeology of the surrounding basin that directly af-fects those formations. The major output from this work willbe injectivity maps for each sedimentary basin. The secondphase will involve moving to specific sites within key basinsfor far more detailed study. This will include prediction ofCO

2

trapping mechanisms from modelling of the water–CO

2

-rock interactions, economic modelling for transporta-tion, compression and injection, examining technology formonitoring the movement of the CO

2

, and investigation ofany environmental or safety issues. Physical and chemicalattributes of Australia’s naturally occurring CO

2

accumula-tions will also be studied in support of these predictions.

THE GLOBAL WARMING ISSUE — AN OIL COMPANY PERSPECTIVE; PROSPECTS FOR CO

2

INJECTION?

Shinn, John, Chevron, Richmond, CA

The global warming issue poses a number of potentialchallenges and opportunities for the oil industry. Ongoingnegotiations are defining not only targets for greenhouse gasreduction but also mechanisms to enable countries and com-panies to respond. A broad range of options exist to reduceor sequester emissions. Underground injection of CO

2

couldprovide an interesting alternative. In this paper, we will dis-

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cuss some of the important technical, economic, and politicalquestions that surround the ultimate viability of this option.

UNDER-EXPLORED BASINS OF AUSTRALIA: AN INVENTORY

Stephenson, A. E., Australian Geological Survey Organisation, Canberra, Australia

Most of Australia’s continental margin has not been thor-oughly explored for petroleum and can be regarded as “fron-tier.” In order to understand the petroleum and other resourcepotential of Australia’s frontier basins, it is first necessary toknow the location and physical and geological attributes ofthose basins. Whilst data on particularly larger basins havebeen collated locally, no comprehensive inventory of Aus-tralian basins has existed at a national scale. In addition, re-cent work associated with the Law of the Sea has seenknowledge of offshore basins in frontier areas expand con-siderably. Australian Geological Survey Organisation’s Ba-

sin Evaluation Project has addressed these shortcomings bycompiling an inventory of all known sedimentary basins inAustralia and its ocean territories, to be made available onCD and via the Internet, as part of the national geosciencedatabase. The detail available on each basin varies with bothits relative resource importance and our current level ofknowledge. The inventory also cites key references and fur-ther sources of information and includes hot-links. It is inpart designed to give an overview of Australian basins tothose in the international petroleum industry not familiar withthe details of Australian geology and petroleum potential.

Current geological knowledge suggests that many Austra-lian underexplored offshore basins may have generated sig-nificant quantities of hydrocarbons. The most prospective ofthese include the Bight, Browse, Duntroon, Maryborough,Otway, Perth, Roebuck, Sorell, and Townsville Basins, plussome newly discovered basins on the Lord Howe and SouthTasman Rises. Onshore, the Georgina and Officer Basins inparticular may have untested petroleum potential.