MINISTER’S STATEMENT

he Bracks Labor Government was elected with a clear view of the importance of the energy and resources sector and the particular challenges that must be met if the industry is to continue to make a valuable Tcontribution to the wealth and wellbeing of all Victorians. Oil and gas make a significant contribution to the Victorian and the national economies. It has been a remarkable year for Victoria's petroleum industry since the last Victorian supplement was released. The outstanding record of success, with five back-to-back gas discoveries in the onshore Port Campbell region by Santos, was followed by the offshore successes at Thylacine-1 (just in Tasmanian waters) and Geographe-1 by the Origin consortium. Esso/BHP Billiton has also discovered gas at the East Pilchard-1 well in the Gippsland Basin. This year has been pivotal for the State. These new discoveries provide some real opportunities for significant changes in the southeastern Australian gas market structure. New potential markets and customers, both in Victoria and interstate, are developing, in turn leading to development projects and stimulating high exploration activity levels. The Bracks Government remains committed to its reform agenda in the oil and gas sector. The Pipelines Act General Discussion Paper has been released for comment on the objectives and purpose of regulation of the pipeline industry and on other specific issues. Encouragement of exploration and establishment of new sources of supply will ultimately enhance security of gas supply to Victoria. Victoria is also continuing to support responsible exploration and development of the industry through the Victorian Initiative for Minerals and Petroleum. Provision of basic and value - added information and its preservation for future explorers remains a priority. That policy and the development of the region's gas markets is stimulating the upstream and midstream gas sector. Last fiscal year (2000/1) witnessed the greatest investment in exploration expenditure for a decade (over $75 M). That investment has already been eclipsed at mid year in 2001/2. An estimated $165 M has been spent by the end of January 2002 on exploration work and the completion of a busy year is projected. The largest ever offshore 3D seismic acquisition program in the southeastern Australian region is being conducted by the Esso/BHP Billiton joint venture at the time of writing. In 2002 it is anticipated that the first new producer in the Gippsland Basin, OMV, will be supplying gas from the Patricia Baleen field. The gas pipeline to Tasmania is also under construction, linking that state to the Bass Strait fields and ultimately to the rest of the nation. Gas development and pipeline projects valued at up to $2 Billion are planned for the next five to six years. Articles in this supplement will provide greater detail as to the scope and timing of these projects. Victorian acreage, released at the 2002 APPEA conference, will again be accompanied by the comprehensive technical reports that supplement the national release and also cover the areas exclusively under the State's jurisdiction. The successes in the Otway Basin have highlighted this region internationally and it is anticipated that there will be considerable interest in the offshore Otway areas. I am confident that the three offshore areas offered in Australia's historically most prolific Gippsland Basin, will also be closely considered by the industry. The Bracks Government is developing a petroleum industry that contributes substantially to the wealth and wellbeing of all Victorians, while meeting contemporary community expectations for social and environmental outcomes. I would like to extend thanks to the industry contributors to the supplement. With the Department summaries I trust it will provide a useful reference for both those companies already established in Victoria, as well as those who are new to the State.

Candy Broad Minister for Energy and Resources, Minister for Ports, Minister Assisting in State Development

I Minister's Statement IFC IContentsMPV Division Structure 3 IMinister'sMPV PetroleumStatement. .Regulation ...... Unit ...... IFC Lakes Oil HoracioExploration Haag Activities in Victoria Update 4 I Major Projects Reflect Renewed Confidence Lakes Oil GeoffNL . . Collins...... 105 Petroleum Branches of E&M Division...... 1 I Petroleum Web Site BASIN STUDIESGeoff CollinsGROUP UPDATE 5 IINFRASTRUCTURE2001 Release of Exploration Areas Dr Mike Woollands,Dr Mike Woollands David Wong And Dr Tom Bernecker Surgein inHighlights Infrastructure Otway Development Basin Potential to Tap Gas Discoveries Otway Basinand . .Andrew ...... Constantine ...... 116 IGeoffGippsland Collins . .Basin: . . . . . Potential...... and . . . .Opportunities ...... 2 D. Wong, D. H. Moore & Dr T. Bernecker 9 I Exploration Activities in Victoria GippslandMaher Basin . Megallaa...... 1211 Feasibility Studies in Progress for New Offshore Otway Basin Fields WoodsideOffshore Energy Otway .Exploration ...... Enters. . . . .New . . . Phase...... 2 News fromOrigin Basin Energy Studies & .Woodside ...... 15 Strike's Otway Gas Opportunity Coming Together Strike Oil Nl SouthernBusy Year Gas Planned Pipeline for - FulfillingSantos with a NeedIncreased for TwoExploration States’ inPipeline Otway Basin PETROLEUMSANTOS RESOURCES Ltd & PRODUCTION DukeOil Energy and Gas International Opportunity. in. . Bass. . . .Straight ...... 3 Eagle Bay Resources Melville Upside Potential of 251mmb in Golden Beach Sub-Group PetroleumBass Resources, Strait Oil Production Company and Drilling Activities In Victoria SEA Gas Project Set to Flow in Late 2003 Dr Kourosh Mehin ...... 16 IAustraliaPetroleum National Resources Power. . and. . . .Operational ...... Activities...... Update...... 4 Dr Kourosh Mehin 18 I Tuna / West Tuna M-Sand Outstanding PETROLEUM INFORMATION EXPLORATION ACTIVITIES Performance from a 12 m Oil Rim Esso Australia Ltd. 19 Petroleum Information Group Update IAcreagePetroleum Release Information and Industry Group Activities Update in Victoria Bob HarmsBob. . . Harms...... 1820 IMaherMPV Megallaa Reports. .Listing ...... 5 21 I EMD Reports Listing ...... 19 GippslandList of 3DTenements Seismic Survey - A Boost For The Northern Fields Life 22 IEssoTenements Australia Pty and Ltd Pipelines...... Map...... 6 List of Tenements ...... 20IBC I Otway Seismic Line OBC New Otway2002 Horizons Tenements and Pipelines Map ...... IBC Santos Ltd...... 7 Santos’ 3D Map, TWT for Top Waarre ...... OBC Otway/Sorell Basin New Seismic Fugro Multi Client Services (formerly Seismic Australia) and Fugro Geoteam ...... 9 ENERGY & MINERALS DIVISION

Richard Aldous Executive Director Energy and Minerals Ph: +61 3 9412 4508 Fax: +61 3 9412 4183 Email: richard.aldous @nre.vic.gov.au Energy and Minerals is a division of the Department of Natural Resources and Environment. It seeks to deliver the lowest sustainable energy prices for Victorian consumers with assurance of safety and security of supply. It promotes and regulates mineral and petroleum exploration and extraction; administrates and reforms policies related to these activities, including mining and transmission pipelines.

Kathy Hill Manager Petroleum Development Ph: +61 3 9412 4208 Fax: +61 3 9412 5156 Email: [email protected] Responsible for facilitation of petroleum exploration and development, acreage marketing, geological studies, data management, reservoir engineering and legislative policy reform.

Rob King Manager Minerals and Petroleum Regulation Ph: +61 3 9412 5069 Fax: +61 3 9412 5152 Email: [email protected] Responsible for establishment of technical aspects of licence conditions and approvals of drilling programs, pipelines, health, safety and environment monitoring. Also responsible for granting Petroleum Development Managers renewal and administration of licences and fees.

Mike Woollands Kourosh Mehin Manager Basin Studies Manager Petroleum Resources Ph: +61 3 9412 5135 Fax: +61 3 9412 5156 Ph: +61 3 9412 5082 Fax: +61 3 9412 5156 Email: [email protected] Email: [email protected] Basin Studies have developed a knowledge of Victorian Basins and produce Petroleum Resources monitors the level of reserves within Victoria and regional geological reports to assist with the assessment of acreage. The provides geological/technical advice in respect of drilling programs and group also funds studies and acquisition of data where this will promote tenement applications. the acreage. Geoff Collins Maher Megallaa Manager Petroleum Projects Manager Acreage Release Ph: +61 3 9412 5095 Fax: +61 3 9412 5156 Ph: +61 3 9412 5081 Fax: +61 3 9412 5156 Email: [email protected] Email: [email protected] Provides assistance in liaising with government agencies for all projects Handles the co-ordination of acreage release processes and the marketing including new transmission pipelines. of gazetted acreage, including the preparation of promotional data.

Bob Harms Minerals & Petroleum Regulation Manager Information Services Ph: +61 3 9412 5053 Fax: +61 3 9412 5156 Horacio Haag Email: [email protected] Manager Petroleum Regulation Unit In Victoria data is required to be submitted to the government. Information Ph: +61 3 9412 5101 Fax: +61 3 9412 5152 Services manages this data and, after confidentiality periods, handles Email: [email protected] distribution to companies requesting the data. Responsible for the management of the Petroleum Tenements, assessment and acceptance of safety cases, environmental management plans, approvals of seismic, drilling, and Workover operations. Department of Approvals relating to pipeline construction and operations.

Natural Resources Front Cover: A photograph courtesy of Duke Energy International of the 30,000 tonne Allseas Pipelay vessel, Lorelay. This ship is installing the and Environment 301 km offshore section of Duke Energy's Tasmanian Gas Pipeline from Victoria to Tasmania, a natural gas pipeline that will provide Tasmania with natural gas for the first time (see Duke's article page 3). On completion of this work the Lorelay will be used in building two other pipelines in offshore Energy & Minerals Division (EMD), formerly Minerals & Petroleum Gippsland Basin to bring gas ashore one from OMV and Diamond Gas Victoria, is a division of the Department of Natural Resources and Resources Patrician Baleen Field and the other from Esso/BHP Billiton Bream Environment (DNRE) Field (see page 2). EMD has its headquarters at: 240/250 Victoria Parade, East Melbourne, Victoria 3002 Outside Back Cover: A 3D visualisation of the seismic two-way time The Petroleum Development Branch is located at: structure of the Waarre Sandstone, draped with full-stack seismic amplitude, Level 7, 240/250 Victoria Parade, East Melbourne, Victoria 3002 over Santos' gas fields within the onshore Port Campbell Embayment P.O. Box 500, East Melbourne, Victoria 3002 (PPLs 4, 5 and 7). The utilisation of the 3D seismic technique and Ph: +61 3 9412 4208 Fax: +61 3 9412 5156 2002 associated amplitude variations has lead to reduced exploration risk in the EMD Web-site: http://www.nre.vic.gov.au/minpet/ area (see Santos article page 7). This image is published with permission of Santos Ltd.

This publication was produced by Oilfield Publications Pty Ltd T/A RESolutions Resource & Energy Services on behalf of PESA PESA News April/May 2002 1 P.O. Box 24, Innaloo City WA 6918 • Ph: +61 8 9446 3039 • Fax: +61 8 9244 3714 • Email: [email protected] INFRASTRUCTURE DEVELOPMENT

SURGE IN INFRASTRUCTURE DEVELOPMENT TO TAP GAS DISCOVERIES BY GEOFF COLLINS, MANAGER, PETROLEUM PROJECTS

evelopment has continued apace in Also, gas discoveries in the onshore Otway Victoria over the last year. The Basin have been nothing short of remarkable. Doutstanding discoveries in offshore There was a 100% success rate in 2001, Otway Basin at Geographe and Thylacine, bringing in five discoveries all within a few together with new, smaller, gas discoveries kilometres of the existing gas plant and onshore, have resulted in a substantial lift in facilities (see Santos article page 7). Victoria's gas reserves. Thylacine and Geoff Collins Geographe are relatively large fields and have The impact of the introduction of 3D seismic added an amount equal to about a quarter of has been dramatic. Very few wells drilled on industry in Victoria. Victoria's offshore gas the remaining discovered reserves in recent 3D grids in Victoria have failed to be industry is on the brink of its busiest growth Gippsland. Feasibility studies have already discoveries. The results of the substantial Esso phase since the discovery of the Bass Strait oil commenced on how the gas from these new operated 3D seismic program in the Gippsland and gas fields in the 1960s, with major finds can be brought on stream (see Woodside Basin will be of interest (see Esso article page 6). projects worth more than $A1 billion set for article below) development. It is difficult to remember that only five years The Minerva gas field (which lies offshore in ago the Victorian gas industry was so very the Otway Basin about 12 km south of Port different. Then, it was the Esso/BHPP Campbell - see location inner-cover) now has a monopoly producing gas and selling it on long gas sales agreement with Australian National term contracts to the government owned Power (ANP) that will enable the project to be monopoly transmitter/distributor/retailer with delivering gas by 1st January 2004. BHP the market limited to Victoria. Now, there are Billiton is currently calling for tenders for the multiple producers through multiple gas development of an offshore facility on the plants, supported by a commercial Minerva field and associated sub-sea pipeline underground gas storage capacity, with that and onshore gas processing facilities. number increasing.

The Bass Gas project to develop the offshore Supply competition has increased with the Yolla field is well into its environmental construction of the two links to NSW and is to Patricia Baleen Project: New technology used by Cherrington, Australia. Pipeline string being assessment phase and it also has a gas sales be further increased with a link to Adelaide. loaded into thrust rig at Orbost for insertion agreement in place; 260 PJ over 15 years to Two groups (see articles page 3 and 4) are into HDD hole. Origin Retail, with first gas in the first half of moving ahead with plans to build a gas 2004. Origin Energy will bring the gas and pipeline between Port Campbell in associated petroleum liquids from Yolla to southwestern Victoria and Adelaide to serve onshore east of Westernport Bay, near Cape the rapidly expanding South Australia market Liptrap. (location in the inner-back cover).

Construction has commenced on development Downstream there are multiple, privately of the Patricia Baleen gas field, on the owned transmitters, distributors and retailers development of the gas in the Bream field, and with long term contracts and a wholesale on the Tasmanian Natural Gas Pipeline (inside market in operation. The accessible market is back cover). the entire southeast of Australia, including Tasmania. The future is looking bright for the Esso/BHP Billiton Bream Project: The Tasmanian Natural Gas Pipeline (Duke Lift, lower and lay pipeline into trench. Energy project) is a 714 km, high-pressure, 350 mm-gas pipeline (one of the largest infrastructure projects in Australia) started before last Christmas. The pipeline will EASIBILITY TUDIES IN ROGRESS FOR transport up to 40 PJ of gas from Longford in F S P Eastern Victoria to Bell Bay on the north coast of Tasmania, before being branched to supply EW FFSHORE TWAY ASIN IELDS the entire state. First gas delivery is expected in N O O B F June this year. The giant pipelaying ship, Lorelay, was contracted for this work (see front BY WOODSIDE ENERGY LTD cover and Duke’s article on page 3). oodside Energy Ltd on behalf of Campbell, Victoria in water depths of OMV and its partner, Diamond Gas Resources, Origin Energy Resources Limited, 80-100 m. will build a pipeline from the Patricia Baleen WBenaris International NV and field and a small onshore gas plant near Orbost CalEnergy Gas (UK) Limited has commenced The gas accumulations were discovered by to produce around 50 MMcfgpd into the feasibility studies on the Thylacine and exploration wells Thylacine-1 and Geographe- Eastern Gas pipeline. OMV will use the Lorelay Geographe gas discoveries made in the 1, drilled in May and June 2001. The initial to lay the 2002pipeline after it finishes the Duke offshore Otway Basin in 2001. The two fields discoveries were quickly followed by the pipeline to Tasmania. Gas is expected on are in exploration permits VIC/P43 and T/30P, successful appraisal well Thylacine-2 and a stream for this winter. about 55 km and 70 km south of Port further exploration well, Geographe North-1,

2 PESA News April/May 2002 INFRASTRUCTURE DEVELOPMENT

gas reservoirs and consider various • Recommendations on feasibility of alternatives for their development. the development. There will also be a strong emphasis on environmental More detailed definition studies are expected studies, including discussions with to be carried out through the remainder of government agencies over 2002. It is anticipated that major decisions on necessary approvals for the the development will be made in early 2003 project. with concept selection and identification of gas processing location preferences. Gas The feasibility review, which is due could be delivered to markets by early 2006. to be completed in the second quarter of 2002, will cover issues Scope for Recovery Volumes for the combined such as: Geographe and Thylacine fields are 0.80 Tcf • Potential development concepts dry gas (1.5 Tcf GIIP) and 8.0 MMbbl (wells, infield facilities, condensate, which are initial 100% estimates. pipeline, process and export facilities); Participants in VIC/P43 (Geographe) are • Preliminary development Woodside Energy Ltd (55%), Origin Energy capital expenditure and Resources Limited (30%) and CalEnergy Gas production operating costs; (UK) Limited (15%). Participants in T/30P • Preliminary reserves and (Thylacine) are Woodside Energy Ltd (50%), Fig. 1. Ocean Bounty Rig vessel used in drilling production profiles; Origin Energy Resources Limited (30%) and Thylacine and Geograph. • Market analysis; Benaris International NV (20%). • Economic analysis; • Preliminary project plan for the For more information contact: development; • Government approvals, plans and Annalisa Grubisa takeholder management plans, together External Affairs Adviser with plans for timely environmental studies; Woodside Energy Ltd. • Field appraisal requirements; and Ph: +61 8 9348 4922

SOUTHERN GAS PIPELINE - FULFILLING A NEED FOR TWO Fig. 2. Location of Thylacine and Geograph in relation to La Bella and Minerva fields. TATES IPELINE where only minor gas shows were S ’ P encountered. BY TERRY DWYER, COMMUNITY AFFAIRS The Thylacine-2 appraisal well, which is about 5.7 km to the west of Thylacine-1, was MANAGER, SOUTHERN GAS PIPELINE, production tested at rates of 28 MMscfpd. The drilling program was successfully completed DUKE ENERGY INTERNATIONAL on October 14th 2001.

Thylacine is the largest gas field discovered in ictoria's emerging sources of natural Australia Government appealed to the market the Otway Basin and its discovery was the gas, both from onshore fields near Port for expressions of interest to provide a new highlight of the 2001 exploration campaign. VCampbell and the burgeoning offshore source of competitively priced gas to the State. Thylacine and nearby Geographe have the Otway Basin fields, are on the lookout for Duke Energy International (DEI), and GasNet potential to make a significant contribution to customers. Australia have formed a partnership to accept reserves in southeast Australia and will have the challenge and are well advanced in an important impact on the supply of energy Opportunistically for the Victorian producers, planning to build the Southern Gas Pipeline to Victoria and South Australia. South Australia, its near neighbour to the west, between Victoria and South Australia. has an urgent need for more gas to come into Forecasts by several independent groups the state to satisfy future industrial and power Both companies have impressive credentials in suggest that Australia's consumption of gas generation requirements. the gas pipeline business. DEI forms part of a will increase significantly in the next 15 years, US-based energy merchant with a portfolio of at a time when reserves in Bass Strait and the With over 3000 Mw of combined new power assets in excess of US $58 billion. In the Asia Cooper Basin are projected to decline. This generation proposed for Victoria and South Pacific region, DEI has an extensive portfolio of opens up future opportunities for a new gas Australia in the near future, a continuation of gas pipelines and other energy assets in source, such as the offshore Otway Basin, to at the national network of gas pipelines to Australia, including the 795 km Eastern Gas least partially meet this demand. Woodside, provide interconnection between Victoria and Pipeline from Sydney to Melbourne, and the Origin, Benaris and CalEnergy have already South Australia is a need that has to be fulfilled. Tasmanian Gas Pipeline, currently under been encouraged by early expressions of construction. market interest. Currently, South Australia is energy constrained,2002 having only the one gas pipeline GasNet is one of Australia's leading gas The early stages of the current feasibility supplying the State's entire gas needs. transmission companies with a high-pressure studies will increase understanding of these Responding to industry needs, the South network of almost 2,000 km, transporting

PESA News April/May 2002 3 INFRASTRUCTURE DEVELOPMENT

almost all of Victoria's southeast of South Australia, close to Mount natural gas supplies to Gambier, Naracoorte and Murray Bridge. 1.3 million households These centres are close enough to the pipeline and 40,000 commercial route to avoid expensive laterals. and industrial users. Market opportunities for an alternative gas At a cost of more than supply in South Australia include the Torrens $250 million, the Island power station and existing and future planned Southern Gas gas-fired power stations, the proposed South Pipeline is a significant Australian Magnesium (SAMAG) development, development which major industrial users, and new and existing Lorelay laying pipeline into Bass Strait. will traverse 690 km of players in the South Australian industrial and countryside between retail markets. The giant pipe laying Iona, near Port public display. Final regulatory approvals for the ship Lorelay. Campbell in western The presence of a new pipeline from Victoria project are expected by mid 2002. Victoria, to Adelaide. is also expected to stimulate development of new power generation and industrial projects. The Southern Gas Pipeline project will be Potential new gas demands have been either a 350 or 400 mm (nominal bore), identified along the route in regional western Pre development activities for the Southern Gas buried, high-pressure natural gas pipeline, Victoria and in south eastern South Australia, Pipeline are well advanced. At the time of with an initial capacity of at least 45 PJpa and and the alliance has been active in pursuing writing, all of the 2000 property owners had an ultimate capacity of 90-120 PJpa. new customers, which need a competitively- been visited and the entire route had been priced, long term source of gas. surveyed. The environmental impact assessment Construction is scheduled to commence in late has been completed and the Victorian permit 2002 and continue through to October 2003, The pipeline will pass close to Portland in application and the South Australian licence with commercial operation contracted for western Victoria and then traverse through the application have been submitted and are on January 1st 2004.

SEA GAS PROJECT SET TO FLOW IN LATE 2003 BY JIM KOUTS, CORPORATE AFFAIRS MANAGER, AUSTRALIAN NATIONAL POWER

he South East Australia (SEA) Gas project The gas will come from Minerva (15 km offshore The SEA Gas project will create a corridor for to transport gas from offshore Victorian from Port Campbell) and Yolla (100 km offshore major Origin Energy growth projects including Tfields to Adelaide is on track for from Western Port). the proposed development of the new completion in October, 2003, according to its Thylacine/Geographe gas discoveries in the joint venture proponents, Origin Energy and The open access, 360 mm diameter, 15 MPa offshore Otway Basin, the SEA Gas project itself, Australian National Power (ANP). Origin Energy pipeline will allow Origin Energy, Australian and the Quarantine Power Station which is is a major integrated energy company focused National Power and other interested parties to currently being commissioned. Other merits are on natural gas with complementary interests in ship up to 70 PJpa - lifting the inward capacity that the open access gas pipeline will deliver the exploration and production, power generation, for gas into Adelaide by more than 80%. energy equivalent of three times the existing and energy retailing and ANP is a subsidiary of electricity inter-connector between South one of the world's largest independent power Origin and ANP are Foundation shippers on the Australia and Victoria, and will add up to 80% companies, International Power. pipeline while agreements are in place for to inbound gas supply to Adelaide. SAMAG - the proponent of an $800 magnesium In South Australia ANP has successfully smelter at Port Pirie - to access gas. As well as meeting the need in South Australia constructed the Pelican Point Power Station and and Victoria for a new independent source of owns the Synergen peaking generators. As well as providing capacity to meet the fuel energy, the SEA Gas pipeline is set to create needs of other power generators or industrial significant regional benefits for both states, The SEA Gas pipeline project is progressing consumers of gas, the planned SEA Gas pipeline including: well, and so far works completed include: will supply power stations operated by • Alleviating gas supply security issues in • the project route has been fully surveyed; Australian National Power and service Origin South Australia and Victoria; • comprehensive environmental impact Energy's retail and growing generation business • Promoting development of the Minerva studies have been undertaken; in Adelaide. and Yolla gas fields; • community consultation has been completed Continued On Page 5 and led to Environment Australia approving the project; and • engineering procurement and construction contract tenderers for the project have been short-listed.

SEA Gas will invest approximately $300 million in the pipeline project, which will carry gas sourced from offshore Victorian fields 680 km from Iona to Pelican Point along an inland route passing south2002 of Casterton and south of Tailem Bend. Lateral pipelines along the SEA Gas route could Pelican Point Power Station, Adelaide, owned and bring gas to regional commiunities. operated by SEA Gas joint venture partner ANP.

4 PESA News April/May 2002 EXPLORATION ACTIVITIES

2002 ACREAGE RELEASE AND INDUSTRY ACTIVITIES IN VICTORIA BY MAHER MEGALLAA, MANAGER, ACREAGE RELEASE

hydrocarbon potential of the offshore Otway south of the Seaspray area, where sub- Basin block is given in pages 11-12 and on commercial hydrocarbons were encountered the Gippsland Basin blocks in pages 12-15 of in Woodside wells. Area VIC/G-02(1) is this supplement. The VIMP reports and other located in the Strzelecki Group province, supporting acreage release posters and comprising rocks that have not been as material will be on display at EMD booth in thoroughly explored as their counterparts (the Maher Megallaa the APPEA Conference in Adelaide. You may Otway Group sediments) in the Otway Basin. also view previous acreage release VIMP Drilling and seismic control in these blocks is he Department of Natural Resources and reports, listed in page 19, by visiting our NRE limited. Environment will release eleven (11) web-site mentioned at the end of this article. Tpetroleum exploration areas at the April Commonwealth Waters 2002 APPEA Conference. The Commonwealth Otway Basin Acreage [Areas V02-2, V02-3 & V02-4] of Australia and the State of Victoria will jointly release four offshore areas and concurrent with State Coastal Waters The areas are adjacent to major producing oil this release, Victoria will also release seven [Areas 02-1(v), -2(v), 3(v) & 4(v)] and gas fields and are within proximity to areas, two onshore and five offshore (3-notical established infrastructure and commercial mile zone). These areas has the potential for containing centres. They are close to the growing small gas accumulations exemplified by the Southeastern Australian gas market and also to The location of all areas is shown on the Permit fact that 2001 onshore drilling in PEP- the planned new gas pipeline network to Map in the inner back cover, which are: 153&154(a) to the immediate vicinity of 3(v) South Australia and Tasmania. They are within • Commonwealth Waters: One area in & 4(v) resulted in 7 out of 8 wells as gas proven petroleum systems where several play Otway Basin (V02-01) and three areas in discovery [Croft-1, Lavers-1, McIntee-1, types with untapped potential in deeper Gippsland Basin (V02-2, V02-3 and V02-4). Tregony-1, Naylor-1, Penryn-2 and Butress-1]. stratigraphic levels are interpreted from • State Waters: Five coastal waters areas, of Although these discoveries are small, but their existing good well and seismic control which four in the Otway Basin (02-1(v), - close proximity to Santos Heytesbury gas (see page 12). AREA V02-2 comprises whole 2(v), 3(v), 4(v)) and one in Gippsland Basin plant has ensured they are commercial (see and parts of eleven (11) graticular blocks (630 (02-5(v)). back cover). Subject to completion of the km2) and lies immediately north of the • State Onshore: Two areas, one in pipeline construction, the first gas deliveries Snapper, Marlin-Turrum and Tuna oil and gas Gippsland Basin (VIC/G-02(1)) and one in from these discoveries will flow into fields. It is located in water depths of less than Murray Basin (VIC /M- 02(1)). Melbourne's gas markets very soon. 75 m. AREA V02-3 comprises ten (10) graticular blocks (680 km2) and lies EMD has prepared VIMP report 74 (see page 19) Commonwealth Waters immediately north of the Basker-Manta and on the hydrocarbon prospectivity of the 2002 [Area V02-1] Kipper fields and west of the Sole gas field. Offshore Gippsland gazettal blocks. A brief Water depths are generally less than 200 m. summary of the petroleum geology and Area V02-1 is located 45 km southwest of AREA V02-4 comprises two (2) graticular Port Campbell and comprises 30 graticular blocks (135 km2) and is located approximately blocks (1874 km2). Around 80% of the area 80 km in a southeasterly direction from Lakes Continued From Page 4 are located in water depths of less than 200 m. Entrance. A number of oil and gas fields lie in The block is under-explored with only two close proximity to this area [Basker-Manta oil • Creating new markets for the Otway Basin wells drilled in it. V02-1 is in a proven gas and gas field to the northeast, the Flounder, gas discoveries, particularly the new province adjacent to recent and existing Halibut-Cobia and Mackerel oil fields to the Thylacine and Geographe gas fields; discoveries at Thylacine (600 Bcf GIP) and west and the Blackback oil field to the south]. • Creating direct regional benefits of more Geographe (500 Bcf GIP) in the central part of It is located on the flank of the Bass Canyon, than $40 million along the construction the basin and also at La Bella (210 Bcf GIP) in water depths exceeding 500 m. corridor (including up to 300 construction and Minerva (575 Bcf GIP) fields. The block jobs) and up to $1 billion in future offshore has potential for oil discovery, as Late Murray Basin Acreage gas developments in Victoria; and Cretaceous and Cainozoic play fairways are • Providing customers, residential users and interpreted to exist. It has the advantage of [Area VIC/M-02(1)] industries (eg power generators, timber and being close to growing Victorian gas market, minerals processors, an olive processing established gas transmission network linked It is located in the epicratonic Murray Basin facility and the wine industry) with clean to New South Wales and planned/under- which is also a Cainozoic stratotectonic gas by a lateral link. This lateral link will construction gas pipelines to South Australia feature underlain by a number of infrabasins be part of a network of lateral pipelines and Tasmania (see page 2 and inside back or troughs containing Late Carboniferous, bringing gas to key regional centres along cover). Permian and Early Cretaceous sediments. The the SEA Gas pipeline route. The final size troughs extend in a NE direction into NSW and timing of the lateral pipelines will Gippsland Basin Acreage where the depth to the Early to Middle depend on key load commitments Palaeozoic basement is less than 1000 m. The currently being negotiated with a range of Victoria [Areas 02-5(v) & VIC/G-02(1)] basin is poorly explored with only 8 wells users. drilled in its Victorian sector. Area 02-5(v) is located in the coastal strip to Further information about the project is the southwest2002 of the Golden Beach gas available by visiting www.seagas.com.au or accumulation (approx. 75 Bcf GIP) and to the contact Jim Kouts on 0417 866 474.

PESA News April/May 2002 5 EXPLORATION ACTIVITIES

Applications Further information on gazetted blocks, Closing Date For Bids conditions and criteria for selection and Both the State and Commonwealth acreage submission of applications can be seen on: - Applications close at 4 PM (EST) as below : - will be released under the relevant Petroleum Commonwealth (ITR) web-site: • Commonwealth areas V02-1, V02-3 & Act's competitive work program bidding http://www.industry.gov.au/resources/ V02-4 on April 10th 2003 systems. Invitations to submit bids will be petroleum.html • Commonwealth Area V02-2 on October under the Commonwealth Petroleum State of Victoria (NRE) web-site: 24th 2002 (Submerged Lands) Act 1967 for the offshore http://www.nre.vic.gov.au/ • State Water areas VIC/02(1), 02(2), 02(3), areas, the State of Victoria Petroleum minpet/pet/pet.htm 02(4) & 02(5) & onshore Gippsland Basin (Submerged Lands) Act 1982 for the coastal Or contact Maher Megallaa, Area VIC/G-02(1) on October 24th 2002 water areas, and under the State of Victoria Ph: +61 3 9412 5082 • State onshore Murray Basin Area Petroleum Act 1999 for the onshore areas. Email: [email protected] VIC/M-02(1) on August 1st 2002.

GIPPSLAND 3D SEISMIC SURVEY - A BOOST FOR THE NORTHERN FIELDS LIFE BY ESSO AUSTRALIA PTY LTD

sso Australia and BHPB commenced Over more than 30 years the joint venturers, "The advances in technology have been so acquisition of the largest ever 3D seismic Esso Australia (operator) and BHPB have great that we are now ready to update our Esurvey in the Gippsland Basin in invested billions of dollars in development existing 3D seismic coverage by undertaking October, 2001. infrastructure in Bass Strait. the largest 3D seismic survey we have ever recorded in Bass Strait", he said. The 3,900 km2 Northern Fields 3D will see "By applying the latest in computer enhanced some of the world's most sophisticated array oil field data analysis and interpretation Esso's parent company, US based Exxon of proprietary exploration technology applied techniques, we are confident we can identify Mobil Corporation, spends approximately to one of the most mature offshore oil and gas new opportunities and increase the US$200 million a year in research into producing regions. productive life of our fields", said Esso technologies that improve its ability to Chairman, Robert Olsen. identify, acquire, comercialise and efficiently

2002

6 PESA News April/May 2002 EXPLORATION ACTIVITIES

manage oil and gas resources. In exploration alone it has developed over 150 applications that can combine large volumes of different data types for display in a state-of-the-art, walk-in visualisation centre that allows geoscientists and engineers to coordinate the application of their technologies and quickly interpret geological formations.

With more than three decades of exploration and production around its Gippsland Basin oil and gas fields Esso and BHPB have gathered a vast store of knowledge. By combining this information with exceptionally high-quality data gathered during the Northern Fields 3D Esso and BHPB believe they will see a new round of activities in the basin.

This survey has come about as a result of ExxonMobil's significant advances in Geco Beta aquiring the northern fields 3D sesimic survey. exploration technology. Modern marine seismic data acquisition, data processing and "As stand-alone discoveries they would be The Northern Fields 3D will provide analysis techniques will allow it to gather, difficult to commercialise. However, because geoscientists with a wealth of data that they process and interpret high-quality data quickly of their proximity to our existing fields they will be poring over for many years to come. and economically. Its proprietary tool set has provide us with an excellent opportunity to It will also provide opportunities for some reduced the time required to complete critical further utilise our existing infrastructure." innovative engineering as Esso ponders new resource identification activities from years to opportunities on its existing fields, as well months. Esso geoscientists have been remapping the as options for integrating currently geology right across the northern fields area uneconomic resources and new discoveries In 1999 two smaller 3D surveys, one at and this has highlighted opportunities that at into its extensive Bass Strait production Barracouta and one at Kipper, provided insight the moment are considered high risk. "The operations. into the potential applicability of new 'state of new seismic should help us reduce these the art' 3D seismic in Gippsland. risks", said Dr Schwebel.

"What we saw at Barracouta and Kipper has resulted in our geoscientists rethinking some old paradigms regarding the geology of the Gippsland basin. The new data provided a NEW OTWAY HORIZONS small window on what we could do with high quality 3D seismic data to further refine our BY RICK WILKINSON, SOUTHERN AUSTRALIA understanding of the geology of known oil and gas fields, as well as potential new BUSINESS UNIT, SANTOS LTD. opportunities", said Esso Exploration Director, Dr Doug Schwebel. Introduction Santos' strategy is based upon three key drivers: As the survey area covers a number of old 3D ecent activity in Victoria and surveys over fields like Marlin, Tuna and particularly the Otway Basin has seen 1. Market and Infrastructure Flounder, it will have a 4D component, with Santos extending its focus into the R Development the fourth dimension being time. important Victorian petroleum provinces and markets. "By comparing the new data with past 3D we Santos first acquired interest in both the expect to get a clearer picture of how the fields Onshore, six exploration wells were drilled in onshore and offshore Port Campbell are being depleted and possibly identify infill the Port Campbell Embayment Waarre Embayment Waarre Sandstone play within drilling opportunities to develop the remaining Sandstone play resulting in five cased and the Otway Basin in 1996. The offshore area oil and gas", said Dr Schwebel. suspended exploration wells (McIntee-1, consisted of exploration acreage that Tregony-1, Croft-1, Lavers-1 and Naylor-1) contained the recently discovered Minerva The Northern Fields 3D seismic will also allow and one successful development well and La Bella gas fields and the onshore Esso to refocus efforts on to commercialisation (Penryn-2). A large 3D seismic programme included the Mylor field discovery. The Port of a number of currently uneconomic was acquired (the 188 km2 Heytesbury/ Campbell area has been a focus of oil and gas discoveries like Sunfish, Remora, Emperor, Nirranda seismic survey) and this was merged exploration for over 40 years, but until Sweetlips and Wirrah. It anticipates that the with the existing Waarre and Curdievale 3D recently there has been only modest levels of new seismic will give it the tools to identify surveys, resulting in a total 3D seismic activity due to limited market opportunities sweet spots in these discoveries that may be coverage of 330 km2 in PEP-153 and 154 (see and supporting infrastructure. economic to develop. back cover). Following Santos' acquisition, the onshore While Esso also hopes to identify a number of Santos also farmed into the prospective Fenton Creek discovery was made in 1997. near-field wildcats, it believes the chances of offshore VIC/P44 block and participated in At that time Santos' focus was predominantly finding more world-class fields like Kingfish or the 546 km2 Casino 3D seismic survey in late onshore. In late 1998 the Victorian Halibut is low. 2001, and the data is currently being Government led a drive to provide better processed. The current Santos acreage security of gas supply to customers in "What we expect to find are smaller, more position within the Otway Basin of Victoria is Melbourne and commenced construction of a complex fields", explained Dr Schwebel. shown in Figure 1. 12" pipeline from Geelong to Iona and the

PESA News April/May 2002 7 EXPLORATION ACTIVITIES

development of the Iona underground gas The VIC/P44 Joint Venture completed the the wet winter months. The ability to 'cream' storage facilities. Soon after Santos proposed acquisition of the 546 km2 Casino 3D seismic the Waarre Sandstone play has been afforded to develop the onshore Otway Basin fields the survey late in 2001, and this data is currently by the application of 3D seismic and the work commenced to construct the being processed. If the 3D seismic confirms implementation of campaign drilling, Heytesbury gas plant located about 7 km the prospectivity as understood from the 2D reducing the exploration risks and costs and from Port Campbell. seismic interpretation, this block could make therefore improving the economics for these a significant contribution to gas supply within smaller onshore fields. The Heytesbury facility was constructed three to four years. adjacent to the existing North Paaratte gas This increased confidence in the prospects facility, using fast track project management 3. Cost Effective Exploration means that it is possible to commercially drill from project sanction in December 1999 to down to modest-size, while retaining a first gas production in August 2000. The plant By putting together a programme of three to satisfactory rate of return. provides the separation of condensate from six wells which are drilled consecutively, the raw gas with its capacity recently significant savings can be made on Future Horizons increased to 30 TJ/day, and an additional mobilisation and materials, delivering a lower 15 TJ/day capacity expansion planned for this per well drill cost. This is extremely Further wells are being considered for the year. important in the onshore Otway where the Waarre Sandstone onshore, as part of a exploration activity window is curtailed by campaign commenced in late 2001. The Heytesbury facility together with other Offshore the VIC/P44 Joint facilities in the Otway Basin such as local Venture will drill the pipelines, storage, and the pipeline initial well on the permit, connection to the Melbourne market ensure following suitable that the necessary market and infrastructure encouragement from the developments are now in place to facilitate Casino 3D seismic survey. further development. Two significant regional onshore 2D seismic 2. Application of 'Fit For Purpose' surveys are currently being planned, one in the Exploration Technology Port Campbell region, and the other targeting the The application of 3D seismic technology eastern extent of the which formed the basis of the intensive 2001 Penola Trough, towards drilling programme of seven wells, was a key the South Australian factor in the exploration success rates enjoyed border. in that year. For further details contact The seismic (and subsequent drilling) Rick Wilkinson on programmes require detailed planning to Ph: +61 8 8224 7304. ensure all environmental, cultural heritage and regulatory issues are observed, as well as minimising disruption to the local primary Fig. 1. Santos' current Victorian Otway Basin acreage position. producers. The seismic surveys were major undertakings, and in 2001 Santos had to obtain agreement of 320 landowners to gain access to the land involved in the survey and around 5,800 temporary gates were installed, used and then restored. The survey team had to traverse more than 1,200 km to conduct the survey.

Knowledge from the 2001 drill programme and studies of historical analogues confirmed that the coincidence of full stack seismic amplitude anomalies and Amplitude Variations with Offset (AVO) response, within structural closure reduced the exploration risk.

An example of the variation of reflector strength with offset is shown in Figure 2, which has been proved to be indicative of gas at this location. The far offsets are noticeably brighter than the comparable near offsets.

Santos farmed into VIC/P44, which is offshore from the current Port Campbell acreage, and contiguous and west of the existing Minerva and La Bella fields. Much of the knowledge from onshore can be applied offshore, particularly2002 the use of 3D seismic. Fig. 2. Amplitude Variation with Offset response indicative of gas.

8 PESA News April/May 2002 EXPLORATION ACTIVITIES

Basins to contain significant oil and wet gas OTWAY/SORELL BASIN NEW SEISMIC accumulations. The Cape Sorell-1 well was drilled adjacent to BY FUGRO MULTI CLIENT SERVICES the Tasmanian mainland and provides a strong indicator for potential wet hydrocarbons in the (FORMERLY SEISMIC AUSTRALIA) AND FUGRO GEOTEAM area. Although an extremely sandy well (being nearshore to Tasmania), it had oil shows Introduction less faulted than the structures further up on throughout the Cretaceous. Recent work by the shelf. The size of these structures is such Geoscience Australia (formerly AGSO) has he deep water Otway and Sorell basins that economical developments of oil or gas revealed a very rich source (TOC 16%, HI have remained under-explored, discoveries may be possible in the future. The 500) in the bottom of the well and it is not Talthough proximity to the Eastern States expected distal facies in the proposed license unreasonable to believe this type of source market makes it an extremely attractive blocks should benefit from a higher degree of may be more abundant and better preserved exploration opportunity. This has been further marine influence, which should reduce the in the deep water parts of the basin. enhanced by the two recent gas discoveries, perceived seal and source rock risks. The Geographe-1 and Thylacine-1. deep water portion of the basin goes beyond Leads 4,500 m, with drilling activity to date only testing the shallow water plays. The best The new 2D seismic data (Fig. 3) shows several source rocks are often deposited and Direct Hydrocarbon Indicators (DHIs) at preserved throughout time in the central deep multiple levels confirming that the deep water portion of a basin. On this basis, we should basin may be generating considerable volumes expect the deepwater Otway and Sorell of hydrocarbons. A preliminary review of the new 2D seismic data implies the possibility of structures of 2-400 km2 in size and hydrocarbon column heights of up to 600 m.

Summary

Fig. 1. Location Map of regional seismic survey. Encouraged by the size of the structures and asso- In May 2001, Seismic Australia and Fugro ciated DHIs, Seismic Geoteam acquired a regional seismic survey Australia proceeded with over the areas covered by the 2001 licensing additional data acquisition rounds. This was followed up in November to enable more detailed 2001 by an infill survey for the 2002 licensing mapping for the upcoming round. A total of 5,658 km of 2D seismic data 2002 licensing round. It is was acquired with long offsets (cable length: anticipated that processing 7,000 m) to help assess this under-explored of all data will be completed area (see Fig. 1). at the time of the APPEA Conference in Adelaide in Fig. 2. West Tasmanian well stratigraphy and correlations. April 2002. Prospectivity (Courtesy of Geoscience Australia) The prospectivity of the Otway and Sorell basins had been considered questionable due to the highly faulted nature of the Otway Basin and the lean character of the perceived source. There had been little oil found in the system and the gas discoveries have contained quite dry gas. The perception was that the faulted nature of the basin would make discoveries small and potentially uneconomic in addition to increasing the seal risk. The two recent back-to-back discoveries, Geographe-1 and Thylacine-1, thought to each contain 1 Tcf of gas have dramatically changed the picture. The size, total hydrocarbon column (up to 280 m) and moderately wet gas found creates a level of excitement in new opportunities in the region.

Geological Background The previous wells on the eastern flank of the Otway and Sorell Basins were very sandy with only minor marine inclusions, as shown in Figure 2. The new deepwater 2D data shows Fig. 3. New 2D seismic section. large compressional structures, significantly

PESA News April/May 2002 9 EXPLORATION ACTIVITIES

LAKES OIL EXPLORATION ACTIVITIES IN VICTORIA UPDATE BY JACK MULREADY, TECHNICAL CONSULTANT, LAKES OIL N.L.

akes Oil was born out of the heady days The limited amount of of the exploration boom at Lakes information regarding LEntrance in the 1940s. Strzelecki Formation reservoir quality led Lakes’ considerable onshore Gippsland Lakes to the drilling of acreage position at that time led to takeover the Boundary Creek-1 by Woodside Petroleum in the 1950s, and the corehole, designed to company became dormant until its re-listing obtain continuous core by May and Mellor in 1985. from the top Strzelecki (Parnassus Zone) where Since that time Lakes has been an active it subcrops at the explorer in the onshore & offshore Otway shallow depth of Basin, onshore Carnarvon Basin, Eromanga around 220 m at the Basin, onshore USA and PNG. crest of the Longford Dome. Gippsland Basin The results proved Late in 1995 Lakes returned to its Victorian spectacularly different Jack Mulready overseeing the acquisition of the Yarram Vibroseis Survey birthplace, taking out the onshore Gippsland from previous expec- in onshore Gippsland Basin. permit PEP-135, (now PEP-155) which tations. Porosity for includes the Lakes Entrance oil field. sands within this zone Subsequently, Lakes acquired permits PEP between 220 and 356 m averaged around Otway Basin 136, 137 and 138, (now renamed PEPs 156, 28%, with permeabilities averaging around 157 and 158), giving it (once again), a 100 millidarcies (mD), and ranging up to 880 For over a decade Lakes has maintained an dominant onshore acreage position, now mD. Lakes is now preparing to drill a second active interest in the Victorian onshore Otway stretching from Wilson's Promontory in the corehole in the vicinity, this time in an Basin, dating back to its first well as operator west to Orbost in the east, and from the coast endeavour to confirm the presence of Golden in 1991 (South Caramut-1). in the south to the Dividing Range in the Beach Formation as inferred from seismic. north. Apart from a short burst of drilling by Lakes then joined with Cultus et al. to explore Arco et al. in the early 1980s, exploration of Lakes' 2002 drilling programme envisages at the potential of permit PEP-111 (now PEP- 152), onshore Gippsland had effectively stalled least two onshore wells. participating in three seismic surveys between following the success in offshore Gippsland in 1996 and 2000. the 1960s, and the subsequent lack of any In PEP-158 York-1, with a programmed TD of local market for gas. 1200 m, is designed primarily as a test of one Lakes also participated in the Howmains-1 well of the few untested robust Top Latrobe Group (PEP-104) in 1995, and most recently joined Lakes quickly embarked on an active structures in the Victorian onshore region. with Essential Petroleum to drill Port Fairy-1 in Gippsland exploration programme which has York-1 is located in close proximity to an PEP-152 in January of this year. Testing of the included: offshore depocentre and close to an latter well is planned for early March. • an airborne magnetometer/scintillometer interpreted migration path. Strzelecki survey of most of PEP-135 and PEP-136; Formation sands located structurally above The large Pretty Hill Formation structures • 2 appraisal wells in the Lakes Entrance sands in Woodside South-1 well to the east (Tower and Taurus) located in the vicinity of field; will constitute a valid secondary target. The Tower Hill provide additional tantalising • 2 wells designed to test the potential for well is scheduled for drilling in late February, targets, which the PEP-152 joint venture structural-stratigraphic entrapment within and results should therefore be available prior hopes to mature for drilling in the near future. the Lower Latrobe Group; to the publication of this magazine. • 25 km of seismic in the Yarram area, The advantages of onshore petroleum • 3 shallow coreholes designed to test for oil Steele-1 is designed as a test of a Strzelecki exploration in Victoria are obvious - shows in the vicinity of a seep located structure identified on 1985 seismic, and is proximity to markets, excellent infrastructure, 10 km SE of Sale; and located a mere 2 km north of the Longford including rail and road access and oil and gas • 3 wells designed to test the potential for gas processing plant. Details are still being pipelines, and the established service industry production from the Lower Cretaceous settled, but it is likely the well will have a TD associated with the Bass Strait fields. Strzelecki Formation, which underlies the of 2000 m or greater, and target both Golden Latrobe Group both onshore and offshore. Beach and Strzelecki Formation reservoirs. Lakes Oil is now hoping to bring its extensive Drilling is tentatively scheduled for early exploration effort in Victoria to fruition. If the All three of these wells (North Seaspray-3, second quarter 2002. current exploration effort proves successful it Trifon-1 and Gangell-1) produced non- will be the culmination of a tradition of commercial gas flows from the Strzelecki Lakes’ two pronged attack is a logical exploration risk taking that began with Formation. Nonetheless they provided outcome of the review of data (seismic, wells, wildcatting syndicates at the Lakes Entrance encouragement for Lakes to re-examine aeromagnetics/radiometrics, gravity and oil field over seventy years ago. existing seismic to try and better define a geochemistry) and its determination to unlock valid Strzelecki target, as well as examining the potential for commercial production from the possibility2002 of fracture stimulation of what onshore Gippsland . are generally tight Strzelecki Formation sands.

10 PESA News April/May 2002 OTWAY BASIN

BASIN STUDIES GROUP UPDATE BY DR MIKE WOOLLANDS, BASIN STUDIES MANAGER, DAVID WONG AND DR TOM BERNECKER, SENIOR GEOLOGISTS

Operators of the various exploration permits in the Otway Basin have planned further drilling activities and seismic data acquisition for this year and in the near future (see Santos article on page 7). It should be noted that all the recent drilling successes in both the onshore and offshore permits in the basin were made based on 3D seismic data.

The petroleum potential for the Otway Basin is enhanced by the close proximity to the Victorian gas market and, particularly, by infrastructure development (see page 2) and the increasing demand for gas in all the Dr Mike Woollands David Wong Dr Tom Bernecker southeastern Australian states.

2002 Acreage Release Areas Otway Basin: waters and Geographe (estimated GIP 400- 600 Bcf), coupled with the 1993 gas Area V02-1 Exciting New Discoveries and discoveries at La Bella (GIP 217 Bcf) and Acreage Opportunities Minerva (GIP 558 Bcf), have established the Area V02-1 is located at the easternmost part hydrocarbon prospectivity of the offshore of the Voluta Trough (Fig. 1), about 45 km he Otway Basin is currently enjoying a Otway Basin. There were also five recent gas southwest of Port Campbell, and is close to tremendous increase in E & P activities. discoveries in the onshore Otway Basin in the five recent onshore gas discoveries. The most TThe recent gas discoveries of Thylacine Port Campbell area, which proved that the recent significant gas discoveries at (estimated GIP 600-1000 Bcf) in Tasmanian onshore Otway Basin is similarly prospective. Geographe-1 and Thylacine-1 are located

Fig. 1. Late Cretaceous structural elements map showing gas field locations (in red) and Area V02-1.

PESA News April/May 2002 11 OTWAY BASIN

AA

Fig. 2. Interpreted composite seismic section from onshore to offshore passing through the southern end of Area V02-1. (see location A-A on Figure 1). The offshore part of this line is reproduced courtesy of Geoscience Australia and their marketing agent Seismic Australia. Reprocessed version of this line is available from Seismic Australia. immediately east of Area V02-1. Water Flaxman Formation and the Belfast Mudstone CONSTANTINE, A. E., 2000: Hydrocarbon depths across V02-1 increase towards the of the Late Cretaceous Sherbrook Group. prospectivity of V00-1 and V00-2, Late southwest, ranging from 50 m along the These units are currently early- to mid-mature Cretaceous Voluta Trough, Offshore Otway northeastern edge, to 1000 m along the for oil in Triton-1 (Rv 0.5 - 1.0%), but little is Basin, Victoria, Australia, VIMP Report 66, southwestern margin. Around 80% of the known about their overall source rock quality Department of Natural Resources and area is located in water depths of less than in V02-1. Elsewhere in the basin, these units Environment. 200 m. The northeastern part of the block tend to have low to moderate TOCs and HIs, GEARY, G.C. & REID, I.S.A., 1998: straddles the Tartwaup-Mussel Fault Zone, and are dominated by Type III and IV kerogens Hydrocarbon prospectivity of the offshore which separates the Voluta Trough from the suggesting they are gas-prone with some oil eastern Otway Basin, Victoria, for the 1998 Mussel Platform to the northeast (Fig. 1 ). The potential. Acreage Release, VIMP Report 55, Mussel Platform hosts the La Bella gas field, Department of Natural Resources and situated 5 - 10 km outside Area V02-1. The primary objectives are the Late Environment. Cretaceous Waarre Formation within tilted Two wells were previously drilled in the area. fault blocks (analogous to those tested at La WOOLLANDS, M. A. AND WONG, D., Esso drilled Nautilus-1 in 1968 in the Bella, Minerva, Thylacine, Geographe and the (Eds), 2001: Petroleum Atlas of Victoria, southeast part of V02-1. It was drilled in onshore Port Campbell gas fields). The Australia. Department of Natural Resources 100 m of water and bottomed in the Belfast regional seismic section (Fig. 2) across the and Environment, Victoria. Mudstone at a total depth of 2011 mKB. The southeastern part of the V02-1 illustrates this well was designed to test a Tertiary clastic- play. The Waarre Formation in V02-1 is deep wedge stratigraphic play, interpreted to be (greater than 3400 m in Triton-1) and therefore Gippsland Basin: Oligocene in age, developed on the may have a higher reservoir risk than on the northeastern flank of the Voluta Trough. The Mussel Platform. However, the area is well 2002 Offshore Acreage Caters for target interval, however, was composed situated to take advantage of low-stand system all Players Big and Small entirely of marl with no reservoir potential. tract plays within the Cainozoic Wangerrip No hydrocarbons were encountered. and Nirranda groups. These are well he Gippsland Basin has enjoyed developed along the edge of the continental renewed exploration activity in recent Triton-1 was also drilled by Esso in shelf and could be charged from source rocks Tyears. Not only have new players 1980 approximately 2 km west-southwest of within the underlying Otway and Sherbrook entered the scene, but also the established Nautilus-1. The objective was to test the groups. The Paaratte Formation and Timboon players have refocussed their efforts on Waarre Formation in a previously interpreted Sandstone of the Sherbrook Group could also evaluating extra opportunities. For instance, fault closure in the hanging wall of the Mussel act as potential reservoirs, but it is uncertain if Esso has embarked on an extensive 3D Fault Zone. It was drilled in 100 m of water they are present in the area due to its position seismic survey (see page 6) that will cover and the well bottomed in the Waarre relative to the palaeo-shoreline. much of the Rosedale Fault System, a Formation at a depth of 3545 mKB. The target complex tectonic feature that separates the interval however proved both tight and water- In summary, Area V02-1 has the potential to Central Deep from the Northern Terrace, wet. No closure is currently mapped across contain all the elements for successful along which some of the producing fields the structure. exploration, including mature source rocks, (including Kipper and Tuna) are located. A several prospective reservoir units, the new well, East Pilchard-1, was drilled to verify The gas in the La Bella and Minerva gas fields development of both regional and intra- an extension to the Kipper field. The other were sourced from coals in the lower half of formational seals, and the presence of main operator in the basin, BHP Billiton, is the Eumeralla Formation, based on released structural and stratigraphic traps. In addition reassessing the Archer/Anemone discovery. geochemical studies by BHP Petroleum. to the established offshore gas play in the Although deemed a mature basin, the overall These coals would also most likely be the Waarre Formation, which may extend into the consensus is that more hydrocarbon main source of any hydrocarbons present in Voluta Trough, there is additional potential in accumulations are likely to be located in the both V02-1 and elsewhere in the eastern excellent quality delta front and delta plain many undrilled offshore areas and that new Otway Basin.2002 Other potential source rocks in sandstones of Late Cretaceous and Early exploration strategies will be rewarded with the block include the Waarre Formation, the Tertiary age. success.

12 PESA News April/May 2002 GIPPSLAND BASIN

Fig. 3. Tectonic elements map showing 2002 gazettal areas.

2002 Acreage Release Areas because the seal proved to be permeable, the Five wells have been drilled in the area, presence of Latrobe Group pinch-out was Wahoo-1, Sweep-1, Admiral-1, Hammerhead-1 Following the recent offshore release of confirmed, supporting the idea that valid and Leatherjacket-1. The latter well exploration blocks in the Central Deep, reservoir sandstones exist on the terrace. discovered subeconomic oil and gas in top- including two deep water areas in the eastern Longtom-1 encountered 63 m of net gas and intra-Latrobe sandstones. The recovered unexplored part of the basin, the 2002 hosted by three zones within deeper Latrobe oil measured 23-25º API gravity indicating offshore exploration acreage (Fig. 3) Group sediments (Halibut and Golden Beach moderate biodegradation that was confirmed encompasses three blocks two of which Subgroups, see Fig. 4). Post-drill evaluation by geochemical analysis. Well failure in the (V02-2, V02-3) are located on or near the demonstrated poorer than expected reservoir other four wells has been related to ineffective northern basin margin. Only one small block characteristics as well as thinner pay intervals. cross-fault seal (Admiral, Wahoo, Sweep), (V02-4) is located in the eastern Central However, an additional oil leg may be permeable top-sealing Lakes Entrance Deep. developed below the gas column in the Formation (Wahoo, Sweep), lack of effective Longtom structure, given the similarity to the intra-Latrobe seals (Admiral, Hammerhead) Area V02-2, located on the Northern Terrace deep-Latrobe target intervals in the Sunfish and non-generation of hydrocarbons or (Fig. 3), is surrounded by several large oil and and Tuna fields. migration prior to trap emplacement (Sweep). gas accumulations, including Patricia/Baleen to the east as well as Turrum and Snapper in In terms of hydrocarbon prospectivity, the Prospectivity in Area V02-3 falls into two the south. It is noteworthy that the previous operators of the block (Shell, Esso categories: top and intra-Latrobe plays on the southernmost portion of the area extends and BHPP) identified several northern margin Northern Terrace, and deep Latrobe plays beyond the Rosedale Fault System, which plays in the area. They include downthrown adjacent to and south of the Rosedale Fault corresponds to the northern extent of Golden fault traps, similar to those tested in Longtom System. The Latrobe Group thins out rapidly Beach Subgroup sedimentation. These and Patricia/Baleen and stratigraphic pinch- towards the north and is less than 100 m thick sediments rapidly increase in thickness out of the Latrobe Group on the Northern on the southern part of the Northern Terrace. towards the basin centre and are known to Terrace. Additional plays involve inverted Offshore barrier sandstones at top-Latrobe host small hydrocarbon accumulations, as rollover traps within the Golden Beach level represent the most viable targets, identified in Sunfish-1, -2, Sweetlips-1 and Subgroup that are sealed by either the thick provided effective seals are developed. The Remora-1 and sub-commercial quantities in lacustrine Kipper Shale (Fig. 4) or by Gurnard Formation (Fig. 4), a condensed the Archer/Anemone discovery in the prominent volcanic intervals of Campanian interval of marine glauconitic, mainly fine- southeastern part of the basin. age as developed in the Kipper field. grained siliciclastic sediments and known to be gas-bearing in the Patricia/Baleen area, Only two wells, Gannet-1 and Longtom-1 Area V02-3 is located on the Northern also has considerable potential on the (including sidetrack), have been previously Terrace and extends southwards of the Northern Terrace. drilled in Area V02-2. Gannet-1 targeted a Rosedale Fault System. The gazettal block is sedimentary pinch-out play, involving a thin surrounded by three major hydrocarbon The southern part of the gazettal block Latrobe Group wedge that is overlain and discoveries:2002 the Sole gas field in the east, the comprises a thicker Latrobe Group interval, sealed by mud-rich sediments of the Lakes Basker/Manta oil and gas field in the south particularly south of the Rosedale Fault Entrance Formation. Although the well failed and the Kipper gas field in the southwest. System, and provides additional play type.

PESA News April/May 2002 13 GIPPSLAND BASIN

Cretaceous and Early Tertiary, potential hydrocarbon plays would involve non-marine source rocks that are overlain by fluvial/deltaic or near shore marine reservoir sandstones. Seals would be provided by either volcanic horizons or coastal plain mudstones.

Refined stratigraphy to assist explorers The traditional stratigraphic framework used in the offshore Gippsland Basin by the petroleum industry is characterised by wide acceptance of stratigraphic units at the rank of group but a patchy and poorly applied lithostratigraphic nomenclature at the rank of formation, the basic unit of stratigraphy.

For example the basic three-fold subdivision of the sedimentary fill into the Strzelecki, Latrobe and Seaspray Groups, and the more recently proposed Golden Beach Group as a lower subdivision of the Latrobe Group, are widely used in the published literature. In contrast, acceptance of formations within the Latrobe Group has been limited to the Gurnard, Flounder and Turrum Formation near the top of Latrobe and more recently the Chimaera Formation and Kipper Shale near the base of the group. Even though other names have been proposed the bulk of the Fig. 4. Revised stratigraphic column for the Gippsland Basin (after Partridge 1999 and published in Latrobe Group lacks a formation nomen- Bernecker & Partridge 2001). clature that has been acceptable to the petroleum industry. Both, top and intra-Latrobe reservoirs are succession. Volcanic horizons of Campanian developed and are expected to be age that are capable of providing excellent This lack of an appropriate and represented by coarse-grained, well-sorted seals, are widely distributed along the fault comprehensive formation terminology for the offshore sandstones. The eastern part of the system. Given that several graticular blocks of sedimentary succession has both hindered basin was dominated by fully to marginal V02-3 cover the Central Deep, numerous understanding and impeded communication marine processes from the Late Cretaceous prospective leads are likely to be associated of the stratigraphy. To rectify this situation and onwards, consequently, all essential with fault-dependent closures. refine the stratigraphic framework new petroleum systems elements, lower coastal terminology for the Latrobe Group is plain and marine source rocks, porous deltaic Area V02-4 only consists of two graticular introduced (Fig. 4). The new names are to nearshore marine reservoirs and effective blocks that are located in the Central Deep derived from a major review of the mudstone seals, are likely to exist in V02-3. immediately southwest of the Basker/Manta stratigraphy for the whole basin by Partridge field. Other hydrocarbon fields in the vicinity (1999), and will be described in detail in Of particular interest is the rapidly southward include Flounder in the northwest and more appropriate publications. Details of the thickening deep Latrobe Group interval Blackback in the south. The area is flanked by lower Latrobe Group were published at the (Emperor and Golden Beach subgroups) in the western edge of the Eastern Graben recently held Eastern Australasian Basins the Central Deep. While the Golden Beach (Fig. 3) in which the Latrobe Group is Symposium (Bernecker & Partridge, 2001). In Subgroup is only very thin (<20 m) near the believed to exceed a thickness of 3000 m. revising the stratigraphic nomenclature for the Rosedale Fault System, the Emperor Subgroup Gippsland Basin, three factors are deemed is prominently developed in rotated fault- Bignose-1 is the only exploration well drilled crucial: blocks on the southern part of the Northern in the area and targeted a fault-dependent • Priority, current usage and continuity of Terrace, exceeding thickness of 1000 m, and closure at both top- and intra-Latrobe levels. existing stratigraphic names with the aim to thickens towards the Central Deep where While the top-Latrobe target was dry, the well minimise change; seismic profiles indicate thicknesses of up to encountered gas in thin fluvial sandstones of • the necessity to appropriately rank the

2000 m. Near the Rosedale Fault System, the Campanian (T. lilliei) age. The gas is CO2-rich stratigraphic units according to their Emperor Subgroup can easily be drilled, lying (38%) and has a similar composition as the regional scale; and less than 1500 m below sea-level. Although gas in Volador-1, located only 10 km further • the likely acceptance of the stratigraphic to date no hydrocarbons have been recorded south. Volador-1, one of the deepest wells in names. from this stratigraphic level, the lacustrine the basin (4611 m TD), reached the Golden Kipper Shale is not only an important seal Beach Subgroup and penetrated a thick For explorers, the subdivision of the (e.g. Kipper field), but also contains numerous sequence of coal-bearing lower coastal plain hydrocarbon-bearing Latrobe Group sandstone intervals. The shales are over- and sediments (Volador Formation). According to sediments is most relevant. Four subgroups underlain by alluvial and fluvial sandstones thermal modelling, these are considered are discriminated, each of which is bounded that all may have reservoir potential. excellent, oil-mature source rocks. by basinwide unconformities and each consisting of formations that are distinguished The Golden Beach Subgroup is represented Seismic mapping has indicated a possible according to main depositional facies by erosional conglomerates near the Rosedale updip potential of the Volador structure in assemblages. The Emperor Subgroup Fault System2002 and thick fluvial sediments V02-4. Because the area was subject to accumulated prior to continental break-up further into the Central Deep. At Kipper, a alternating marine and non-marine and is characterised by a rift-valley lake facies 200 m gas column is hosted by such a fluvial depositional processes throughout the Upper association comprising lacustrine sediments

14 PESA News April/May 2002 GIPPSLAND BASIN

(Kipper Shale) and erosional material of BERNECKER, T. & PARTRIDGE, A.D. 2001: joined the Geoscience Australia (formerly varying composition from uplifted basin Emperor and Golden Beach subgroups: the AGSO) marketing tour to Houston and margins (Kersop Arkose, Admiral Formation, onset of Late Cretaceous sedimentation in Calgary. This was an opportunity to present the Curlip Formation). The Longtom the Gippsland Basin, SE-Australia. In Hill, relevant details of the 2001 acreage Unconformity marks continental break-up at K.C. & Bernecker, T. (eds.) 2001. Eastern release and demonstrate to the interested the South East Australian margin and the Australasian Basins Symposium, A company representatives the many advantages opening of the Tasman Sea signalling the Refocused Energy Perspective for the Future, of exploring in Australia and specifically in onset of marine sedimentation as part of Petroleum Exploration Society of Australia, Victoria. It would appear that the marketing Golden Beach Subgroup deposition. This Special Publication, p. 391-402. efforts made in recent years have come to stratigraphic unit comprises two formations, fruition with the deep water Gippsland Basin the marine Anemone Formation, dominant in gazettal blocks being awarded to PanCanadian the eastern part of the basin and the fluvial, News From Basin Studies Energy, a newcomer to Victoria. Mike partly deltaic Chimaera Formation, dominant Woollands attended the NAPE conference in in the western segment. In addition, renewed The Basin Studies Group in DNRE's Petroleum Houston in January 2002 and reported that tectonic activity is accompanied by extensive Development Branch had a busy and eventful strong interest exists among North American volcanism mainly along the northern margin. year. Without doubt, the highlight was the explorers in Australian opportunities. heavy involvement in the very successful The associated depositional hiatus, Eastern Australasian Basins Symposium, held Geological work is continuing and the latest represented by the Seahorse Unconformity is at the Hilton on the Park in Melbourne on product soon to be released is the description followed by the Halibut Subgroup that November 25-28th 2001. Apart from of the basement-basin relationship in the contains the reservoir sandstones of the participating in the trade exhibition, members Gippsland and Otway basins. David Moore, majority of oil and gas fields in the basin. The of the group presented two papers and assisted by David Wong, has spent the last two subgroup comprises five distinct formations: contributed to a further three in the Gippsland years assessing aeromagnetic, gravimetric and Barracouta Formation (dominantly fluvial and Otway basins sessions. bathymetric data in order to delineate the sediments), Volador and Kingfish formations likely correlations between basement (dominantly coal-bearing lower coastal plain Another milestone was the completion of the structures and location of hydrocarbon sediments), Kate Shale (a marine interval that long-awaited Petroleum Atlas of Victoria. This accumulations. The result of these separates the Volador and Kingfish publication is the third volume in the investigations will be published as part of the formations) and the Mackerel Formation "Resource Atlas"-series prepared by the VIMP Report series. (near-shore marine sandstones with Petroleum Development Branch. The book, intercalated marine shales). comprising a compilation of maps and The last year also saw a few staff changes. diagrams that summarise the geological and Sadly, Andrew Constantine was lured by Major canyon cutting commencing at least as geophysical framework to the hydrocarbon Origin Energy and, having taken the bait, has early as the Paleocene and extending to the occurrences in the State, emphasises regional joined their Otway Basin team in Brisbane. end of the Early Eocene characterises the petroleum geological aspects rather than Andrew's expertise will be surely missed. upper part to the Latrobe Group in the eastern specific oil and gas discoveries. Throughout Earlier in the year, Jim Driscoll, a geologist part of the basin. The youngest the Marlin the volume, a variety of previously from England, joined Basin Studies and is Channel representing a major sea-level unpublished digital images highlight currently working with Tom Bernecker on the lowstand and a significant hiatus is geological features that have a profound stratigraphy/sedimentology of the Gippsland manifestation of the Marlin Unconformity. control on the distribution of hydrocarbons in Basin. David Moore, who was seconded to the the basins. The Petroleum Atlas is available in group, rejoined the Geological Survey at the The Middle Eocene to Early Oligocene Cobia hard-copy and CD-ROM format (see page 19). beginning of the year and David Wong is Subgroup comprises the Burong Formation about to shift his focus from seismic (lower coastal plain facies) that contains thick As is now a regular feature on Basin Studies' interpretations to project facilitation and will coal seams and the shallow to open marine agenda, exploration acreage was actively commence to work with Geoff Collins. The Gurnard Formation, a condensed section promoted at the APPEA conference in Hobart other team members Eddie Frankel and composed of fine-to medium-grained and at the AAPG convention in Denver. Prior Natalia Liberman are currently busy with glauconitic siliciclastics. The Cobia Subgroup and subsequent to the Denver exhibition, acreage release work and preparation for the is overlain by the fully marine carbonates of Andrew Constantine and Tom Bernecker AAPG and APPEA conferences. the Seaspray Group. These provide the regional seal to the oil and gas accumulations at the top-Latrobe interval.

Undoubtedly, there is scope for further refinement and adjustment of the basin-fill stratigraphy. Efforts are under way to integrate the lithostratigraphy with sequence stratigraphy, correlating the many distinct seismic markers in the basin. The influence of tectonism on the development of regional unconformities also deserves focussed attention. The revised stratigraphic column, however, is a step towards a comprehensive stratigraphy and hopefully will aid all explorationists to better understand the basin.

PARTRIDGE, A.D. 1999: Late Cretaceous to Tertiary geological evolution of the Gippsland Basin, Victoria. PhD thesis, La Trobe University, Bundoora, Victoria, 2002 unpublished, 439p. The Basin Studies Group in 2001: from left to right, Tom Bernecker, Jim Driscoll, Mike Woollands, Natalia Liberman, Eddie Frankel, David Wong, Andrew Constantine and David Moore.

PESA News April/May 2002 15 PETROLEUM RESOURCES & PRODUCTION

PETROLEUM RESOURCES, PRODUCTION AND DRILLING ACTIVITIES IN VICTORIA DURING 2000-2001 BY DR KOUROSH MEHIN, MANAGER PETROLEUM RESOURCES

Overview - Exploration and the Gippsland Basin. Whilst production from Dr Kourosh Mehin Development the major fields is declining, development and work-over activities have reduced the ompared to the 1999/2000 fiscal year, rate of decline in oil production. The basin The 3D seismic surveys in Victoria comprise exploration expenditure in Victoria's provided an average of 162,000 barrels per 271.6 km2 in onshore Otway Basin, (83.6 km2 hydrocarbon provinces increased day (bbl/d) during 2000/01 fiscal year (Fig. 2), in PEP-132 and 188.0 km2 in PEP-153/154), C 2 twofold in the 2000/2001 fiscal year (Fig. 1). which represents 27% of Australia's total 714 km in offshore Otway Basin (VIC/P43), Success rates varied from 33% in the offshore production. and 84.4 km2 in offshore Gippsland Basin Gippsland Basin, 75% in the eastern offshore (VIC/RL5). Otway Basin, including the Tasmanian wells, Gas production, generally linked to demand and 100% in the onshore Otway Basin. level, met the 2001 winter peak demand of Exploration Drilling 800 million cubic feet per day (Mcf/d). On Esso/BHP Billiton continued petroleum average, the winter demand is about 650 Seven onshore exploration wells and one development in the offshore Gippsland Basin. Mcf/d and, in comparison, the summer appraisal well were drilled by Lakes Oil NL, Work-overs at several older oil fields such as demand averages 450 Mcf/d (Fig. 2). Santos and Origin Energy: They include the Flounder, Halibut, Kingfish and West Kingfish uneconomic Trifon-1 and Gangel-1 in PEP- were also carried out. The annual historical oil and gas production 157 of the onshore Gippsland Basin, and profile for Gippsland Basin is presented in Tregoney-1 in PEP-153, Croft-1, McIntee-1, Offshore Gippsland Oil and Gas Figure 3. Lavers-1, Naylor-1 in PEP-154 plus one appraisal well, Dunbar-DW1 in PPL-1, were Production Exploration drilled in the onshore Otway Basin. Five of these wells, including the appraisal well, Production of crude oil and condensate from Seismic Data Acquisition resulted in economic gas discoveries in the the offshore Gippsland Basin has declined onshore Port Campbell area. significantly since the mid-1980s as the A total of 825.4 line km of 2D and 1070 km2 reserves of the first developed major fields of 3D seismic data were acquired in Victoria Eagle Bay Resources and Esso/BHP Billiton approach depletion and the current discovery during 2000/01 (Table 1). The 2D seismic drilled two exploration wells, Northright-1 rate is unable to keep up with production survey consists of 142.7 line km in onshore (VIC/P41) and East Pilchard-1 (VIC/L9) in decline. In the 2000/2001 fiscal year the Gippsland (111.38 km in PEP-161 and 31.3 km offshore Gippsland. Geographe-1 and North major oil and condensate producers were in PEP-137/138), 449.7 line km in offshore Geographe-1 were drilled by Woodside Bream, Flounder, Fortescue, Halibut, Gippsland Basin (VIC/ P41), 233.0 line km in Petroleum/Origin Energy in the offshore Kingfish, Tuna, West Kingfish and West Tuna. onshore Otway Basin (70.5 km in PEP-119, Otway Basin. While East Pilchard-1 These eight fields are now responsible for 99.5 km in PEP-101/111, and 63.0 km in PEP- confirmed a group of stacked gas accumu- more than 78% of liquid hydrocarbons from 159/152). lations within Golden Beach Formation, 4 km South West from the Kipper gas field, Geographe-1 made a significant new gas discovery.

Oil and Gas Reserves Gippsland Basin

As of June 30th 2001, some 3.7 Bbbl of liquid hydrocarbons had been produced from the offshore Gippsland Basin. The remaining reserves are 432 Mbbls.

The gas reserves in the Gippsland fields have been depleted from the initial 9.8 Tcf to 4.4 Tcf. 2002 Gas-in-place in the undeveloped fields of Esso/BHP Billiton and other operating companies in the offshore Gippsland Basin Fig. 1. Petroleum exploration expenditure (1984/85-2000/01). has been estimated to be 3.4 Tcf.

16 PESA News April/May 2002 PETROLEUM RESOURCES & PRODUCTION

Otway Basin

As of 30th June 2001, the gas reserves in the onshore eastern gas fields of the Victorian Otway Basin were reduced from the initial 59 Bcf to 36.7 Bcf (includes the reserves of the undeveloped fields). The developed fields, which are in the Port Campbell region, include the North Paaratte, Mylor, Fenton Creek, Skull Creek, Dunbar, Penryn and Wallaby Creek. The undeveloped fields are Grumby, Langley, McIntee, Tregoney, Lavers, Naylor and Croft.

The initial recoverable reserve of carbon dioxide from Boggy Creek Field in the Port Campbell area was 13.9 Bcf. Cumulative gas production now stands at 2 Bcf and the remaining reserve 11.9 Bcf. Fig. 2. Gippsland oil and gas production (2000/01). The gas-in-place in the undeveloped offshore fields of Minerva, La Bella and Geographe has been estimated at 1.3 Tcf.

Underground Gas Storage The Iona gas field is located approximately 8 km northeast of the township of Port Campbell in southwestern Victoria and is the first field in the State that was converted to an underground natural gas storage facility. TXU (Texas Underground) began operation in mid- 1999 and gas injection commenced in December 2000 after gas production from the Iona field had ceased in November 2000. During the period January-March 2001 a total volume of 10 Bcf was injected (Fig. 4). The facility will ensure that higher than average gas demands are met during winter months. Fig. 3. Gippsland oil and gas production (1968-2001). Leasing

1. The 2000 acreage release resulted in the award of two offshore exploration permits in 2001. Permit VIC/P46 in the offshore Otway Basin went to Essential Petroleum Resources Ltd and VIC/P47 in the offshore Gippsland Basin was awarded to Eagle Bay Exploration Resources. Both permits comprise a six year work program.

2. The Sunfish field retention lease in Gippsland offshore area has been renewed for a further five years.

3. Retention leases for two graticular blocks on either side of Gummy/Basker and Manta fields have also been issued for five years, with a work program directed towards determining feasibility of production early in this term. Fig. 4. Iona field gas production/injection. 4. The Minerva Gas field, which is currently part of retention lease (offshore Port Gippsland Basin Otway Basin Campbell area), is being considered for Total development as feedstock for a fertiliser Seismic Acquisition Onshore Offshore Onshore Offshore plant at Geelong. The La Bella gas field is 2D (km) 142.7 449.7 233.0 0.0 825.4 not currently considered for immediate 3D (km2) 0.0 84.4 271.6 714.0 1070.0 development and will thus remain in a Table 1. retention lease. 2002

PESA News April/May 2002 17 PETROLEUM INFORMATION

PETROLEUM INFORMATION GROUP UPDATE BY BOB HARMS, MANAGER INFORMATION SERVICES dbMap Assets Database Web Site Cataloguing The Petroleum Section of DNRE website http://www.nre.vic.gov.au/minpet/pet is a The Petroleum Information Group has source of information about the Petroleum gradually been cataloguing reports, logs, Development Branch and includes contact tapes and other exploration and production details, publication lists, statistical items. To date, over 57,000 items have been information on reserves and acreage release catalogued with priority given to the most information with prospectivity reports. requested data. The aim is to manage the data Bob Harms to allow maximum use to be made of it, You can also download and view 'The Guide allowing easy access. As items are to the Petroleum Industry in Victoria' - a catalogued, the condition of the item is document specifically designed to assist new The Well Completion Reports (WCR) are assessed and steps put in place to preserve it. players by giving information on legislation, available on DVD at a reduced price procedures, facilities and infrastructure in compared to CD: Catalogued items will, in time, be linked to Victoria. This document is also available in spatial data in dbMap, enabling searches to hardcopy for a cost of $A110 or on CD-ROM • Offshore Otway Scanned WCR DVD be conducted by area. for $A55. Contact Dee Ninis at (1 x DVD-ROM) ($A100); [email protected]. • Offshore Gippsland Scanned WCR DVDs ASCII dumps of these catalogues are available (3 x DVD-ROMs per $A100 package); and so that explorers can find, peruse and Data Packages evaluate the available data. These ASCII • Onshore/Offshore Otway & Gippsland dumps also identify whether the report has • The current list of PDB data packages is Scanned WCR DVD been electronically scanned. provided on page 19 and includes EMD (1 x DVD-ROM) ($A100) Petroleum Reports that support acreage Scanning releases; The complete offshore Gippsland WCRs • Victorian Petroleum GIS CD-ROM ($A33) would take approximately 18 CDs, compared Future requests for copies of reports that have which contains SP-navigation data and to three DVDs. not already been scanned will be charged at cultural data (as Petrosys mapping files) scanning cost. This policy has been put in and is updated every six months with the • DNRE provides Geoframe IESX place to reduce the amount of handling of latest open-file data. This allows explorers workstation dumps consisting of located items and to ensure their preservation. Most to make maps and import the UKOOA seismic trace data and interpretations in Well Completion Reports have been scanned data into their seismic interpretation selected areas. These may cover the and are available on CD and DVD. workstations. It also contains ASCII dumps acreage release areas, or may be of a more from our dbMap database, showing report regional nature. DNRE will also be actively scanning more and data lists; reports in the next three years as part of • Victorian Biostratigraphy Reports Standard Data Services DNRE's data preservation efforts. The most Scanned Images Package (1 x CD Otway requested reports and the datasets most 'at and 1 x CD Gippsland) ($A110); DNRE can provide you with onshore and risk' will be scanned first. DNRE is seeking • Otway Journal Papers CD, containing offshore data, including: input from industry in setting scanning scanned PDF files of APPEA, ASEG, and • Well Completion Reports; priorities. PESA journal papers relevant to the Otway • Composite logs and mud logs; Basin; • Digital wireline log data; Data Preservation • Otway Basin Geochemical Reports CD • Cores, cuttings and side wall cores; contains scanned geochemical reports for • Permit, field, regional and special studies DNRE has a program to preserve well log and the Otway Basin, and also a spreadsheet reports submitted by operators; seismic navigation tapes. It is now extending of geochemistry analysis results; and • Seismic navigation UKOOA data; this effort to onshore seismic, processed data • Gippsland Basin Journal Papers CD, • Seismic processed SEG-Y digital data; and field tapes. DNRE is seeking input from containing scanned PDF files of APPEA, • Seismic field tapes and observer logs; industry to prioritise the preservation efforts. ASEG, and PESA journal papers relevant • Seismic hardcopy sections; and to the Gippsland Basin. (in preparation) • Seismic acquisition and interpretation New Data Submission Guidelines reports. New Data Packages On Dvd New guidelines have been released for the For more information on any of these submission of exploration data to the DNRE has been changing the way that digital projects, please contact: Victorian Government. A copy of the information is being delivered and is now [email protected] guidelines can be emailed to you on request, using DVD-ROMs for some of the data Ph: +61 (3) 9412 5015 see contact below. packages. DVD-ROMs can hold up to 4.7 Gb, compared to only 650 Mb on To order data and listed reports (page 19), CD-ROMs. please contact: [email protected] 2002 Ph: +61 (3) 9412 5169

18 PESA News April/May 2002 EMD PETROLEUM REPORTS LISTING

2002 VIMP REPORT A Guide to the Petroleum Industry in Victoria. OTHER VIMP REPORTS Minerals and Petroleum Victoria, Petroleum Development Unit: Collins G., Parker N. VIMP Report 74 VIMP Report 54 & Platek L. 2000 ...... $100 Bernecker, T., Driscoll, J. & Wong, D...... $250 Mehin, K. & Bock, M. P. 1998 ...... $80 Hydrocarbon Prospectivity of Areas V02-2, V02-3 Cretaceous source rocks of the onshore Gippsland Geological Survey Report 103 and V02-4 in the Gippsland Basin, Victoria, Basin, Victoria Eastern Otway Basin - The stratigraphy, strucrure, Australia geophysics and hydrocarbon potential of the Eastern VIMP Report 43 Otway Basin, Victoria. 1995 ...... $220 Mehin, K. & Link, A. G. 1997 ...... $80 2001 VIMP REPORTS Late Cretaceous source rocks offshore Otway Basin, Various Wells - Well Completion Report CD Victoria and South Australia VIMP Report 70 (WCR of your choice - Maximum 650 Mb per CD) Constantine, A.E. & Liberman, N. 2001 . . . . . $100 ...... $200 VIMP Report 42 Hydrocarbon Prospectivity Package, Eastern Chiupka, J. W., Megallaa, M., Jonasson, K. E., Onshore Otway Basin: VIC/O-01(1), VIC/O-01(2) Otway Basin Published Papers: & Frankel, E. 1997 ...... $110 and VIC/O-01(3). 2001 Acreage Release. A CD contains 68 Otway Basin papers, scanned in Hydrocarbon plays and play fairways of four vacant PDF Format, previously published in the APPEA offshore Gippsland Basin areas VIMP Report 69 Journal, Exploration Geophysics and the PESA Moore, D.H. & Wong, D. 2001...... $150 Journal...... (Free on request) VIMP Report 41 Eastern and Central Gippsland Basin, Southeastern Lavin, C. J. & Muscatello, T. 1997...... $55 Australia; Basement Interpretation and Basin Links. Otway Basin Geochemical Reports: The petroleum prospectivity of the Casterton A CD contains scanned geochemical reports for the Petroleum System in the Victorian onshore Otway VIMP Report 68 Otway Basin and also a spreadsheet of geochemistry Basin Constantine, A.E., Geary, G.C. & Reid, I.S.A. 2001 from the analysis of well samples to be released in ...... $250 mid-August 2001 VIMP Report 31 Hydrocarbon Prospectivity of Areas V01-1 to V01-3, ...... (Free on request) Mehin, K. & Link, A. G. 1996 ...... $65 Offshore Western Otway Basin, Victoria, Australia. Early Cretaceous source rock evaluation for oil and 2001 Acreage Release. VIMP PREVIOUS RELEASES gas exploration, Victorian Otway Basin

VIMP Report 67 2000 ACREAGE RELEASE REPORTS VIMP Report 30 Wong, D. & Bernecker, T. 2001 ...... $200 Chiupka, J. W. 1996...... $55 Prospectivity and Hydrocarbon Potential of Area VIMP Report 66 Hydrocarbon play fairways of the onshore V01-4, Central Deep, Gippsland Basin, Victoria, Constantine, A. E. 2000 ...... $165 Gippsland Basin, Victoria Australia. 2001 Acreage Release. Hydrocarbon prospectivity of V00-1 and V00-2, Late Cretaceous Voluta Trough, offshore Otway VIMP Report 23 OTHER REPORTS Basin, Victoria, Australia. Parker, G. J. 1995 ...... $65 & DIGITAL DATA PACKAGES Early Cretaceous stratigraphy along the northern VIMP Report 65 margin of the Otway Basin NEW RELEASES Smith, M.A., Bernecker, T., Liberman, N., Moore, D. H. & Wong, D. 2000 ...... $275 VIMP Report 22 Petroleum Atlas of Victoria, Australia Petroleum prospectivity of the deep water Gazettal Mehin, K. & Link, A. G. 1995 ...... $65 Minerals & Petroleum Victoria Areas V00-3 and V00-4, southeastern Gippsland Early Cretaceous source rocks of the Victorian Hard Copy & CD ...... $150 Basin, Victoria, Australia. onshore Otway Basin CD ROM Only...... $100 1999 ACREAGE RELEASE REPORTS VIMP Report 21 Victorian Onshore Gippsland & Otway Sarma, S. 1995 ...... $80 Well Completion Report DVD Package VIMP Report 62 Seismic interpretation of the offshore Otway Basin, (a complete set of every open file Mehin, K. & Constantine, A. E. 1999...... $110 Victoria WCR on a single DVD) ...... $100 Hydrocarbon potential of the western onshore Otway Basin in Victoria; 1999 Acreage Release VIMP Report 18 Victorian Complete Offshore Otway Lavin, C. J., & Naim, H. 1995...... $80 Well Completion Report DVD Package VIMP Report 61 The structure, stratigraphy and petroleum potential (a complete set of every open file Smith, M. 1999 ...... $275 of the Portland Trough, Otway Basin, Victoria WCR on a single DVD)...... $100 Petroleum systems, play fairways and prospectivity of the offshore southern Gippsland Basin, Victoria; VIMP Report 17 Victorian Complete Offshore Gippsland Gazettal Area V99-2 Perincek, D., Simons, B., Pettifer., G. R., Well Completion Reports DVD Package & Gunatillake, K. 1995 ...... $110 (a complete set of every open file VIMP Report 60 Seismic interpretation of the onshore western Otway exploration well WCR on three DVD's) ...... $100 Messent, B. E., Collins, G. I., Basin, Victoria & West, B. G. 1999 ...... $110 PREVIOUS RELEASES Hydrocarbon prospectivity of the Offshore Torquay VIMP Report 16 Sub-basin, Victoria; Gazettal Area V99-1 Knight, L. A., McDonald, P. A., Frankel, E. Victorian Petroleum GIS Data CD ROM & Moore, D. H. 1995...... $55 (2002 Version)...... $30 1998 ACREAGE RELEASE REPORTS A preliminary appraisal of the pre-Tertiary infrabasins beneath the Murray Basin, northwestern Victorian Biostratigraphic Reports Package VIMP Report 57 Victoria (Otway Basin and Gippsland Basin CDs) . . . . . $110 Lavin, C. J. 1998 ...... $165 Geology and prospectivity of the western Victorian VIMP Report 15 Victorian Petroleum Reports Voluta Trough, Otway Basin, for the 1998 Acreage Ryan, S. M., Knight, L. A., & Parker, & Publications CD ...... $110 Release & G. J. 1995 ...... $65 Version 0.5c of this CD-ROM includes the The stratigraphy and structure of the Tyrendarra following reports: VIMP Report 56 Embayment, Otway Basin, Victoria • 'Oil and Gas Resources of Victoria. by Malek, R. Megallaa, M., Bernecker, T. & Mehin, K. 1999' & Frankel E. 1998 ...... $110 * All prices include GST but not mailing costs • 'A Guide to the Petroleum Industry in Victoria, Hydrocarbon prospectivity of the Northern Terrace, by Collins G., Parker N. & Platek L. 2000' offshore Gippsland Basin, for the 1998 Acreage • PESA Victorian Supplements 1999, 2000, & 2001 Release • VIMP70, VIMP68, VIMP67, VIMP66, VIMP65, VIMP62, VIMP61, VIMP60, VIMP57, VIMP Report 55 VIMP56, VIMP55 reports in PDF format Geary, G. C. & Reid, I. S. A. 1998 ...... $275 Hydrocarbon prospectivity of the offshore eastern Oil and Gas Resources of Victoria. Otway Basin, Victoria, for the 1998 Acreage Release Minerals and Petroleum Victoria, Petroleum Development Unit: Malek, R. & Mehin, K. 1999 ...... $165 2002

PESA News April/May 2002 19 PETROLEUM TITLES

OFFSHORE TITLES

PRODUCTION LICENCES FIELD(S) TENEMENT HOLDER EXPIRY DATE

VIC/L1, L2, L3, L4 Barracouta and Marlin Esso ✱ / BHP Billiton 24/08/2009 VIC/L5, L6, L7, L8 Halibut and Kingfish Esso ✱ / BHP Billiton 19/09/2010 VIC/L9 Tuna Esso ✱ / BHP Billiton 12/07/2016 VIC/L10, L11 Snapper and Flounder Esso ✱ / BHP Billiton 28/05/2018 VIC/L13, L14 Bream Esso ✱ / BHP Billiton 15/12/2006 VIC/L15, L16, L17, L18 Dolphin, Perch and Seahorse Esso ✱ / BHP Billiton 13/06/2010 VIC/L19 West Fortescue Esso ✱ / BHP Billiton 12/07/2016 VIC/L20 Blackback Esso ✱ / BHP Billiton 01/01/2019 VIC/L21 Gippsland Basin Basin Oil ✱/Diamond Gas Resources/ OMV Timor Sea 26/12/2022

EXPLORATION PERMITS BASIN TENEMENT HOLDER EXPIRY DATE

VIC/P41 Gippsland Eagle Bay ✱ 13/02/2005 VIC/P42 Gippsland Bass Strait ✱ / Inpex Alpha 13/01/2006 VIC/P43 Otway Origin ✱ / Woodside / CalEnergy (UK) 10/08/2005 VIC/P44 Otway Strike Oil ✱ / Santos 10/08/2005 VIC/P45 Gippsland BHP Billiton ✱ / Inpex Alpha 15/05/2006 VIC/P46 Otway Essential Petroleum ✱ 27/05/2007 VIC/P47 Gippsland Eagle Bay ✱ 27/05/2007 VIC/P48 Gippsland Pan Canadian ✱ 16/10/2007 VIC/P49 Gippsland Pan Canadian ✱ 16/10/2007

RETENTION LEASES FIELD TENEMENT HOLDER EXPIRY DATE

VIC/RL1 Mulloway Esso ✱ / BHPB 13/04/2005 VIC/RL2 Kipper Esso ✱ / Woodside / Crusader / 14/12/2003 Woodside Eastern Energy / BHPB/ Santos VIC/RL3 Sole Mobil ✱ / Santos 13/04/2005 VIC/RL4 Sunfish Esso ✱ / BHPB 27/02/2006 VIC/RL6 Basker/Manta Woodside Eatern Energy ✱ / Woodside Energy 29/10/2005 VIC/RL7 La Bella BHPB ✱ / Santos (BOL) 27/02/2003 VIC/RL8 Minerva BHPB ✱ / Santos 29/11/2002 VIC/RL9 Manta Woodside ✱ / Woodside Eastern Energy / News Corp 21/03/2006 VIC/RL10 Gummy Woodside ✱ / Woodside Eastern Energy / News Corp 21/03/2006 VIC/RL1 (V) Golden Beach Bridge ✱ / Basin Oil 24/07/2002

ONSHORE TITLES

PRODUCTION LICENCES BASIN TENEMENT HOLDER

PPL 1 Otway TXU Gas Storage P/L✱ PPL 2 Otway TXU Gas Storage P/L✱ PPL 3 Otway Boggy Creek P/L ✱ PPL 4 Otway Santos (BOL) ✱ PPL 5 Otway Santos (BOL) ✱ PPL 6 Otway Santos (BOL) ✱ / Beach Petroleum PPL 7 Otway Santos (BOL) ✱ PPL 8 Otway Origin ✱ PPL 9 Otway Santos (BOL) ✱ / Beach Petroleum PPL 10 Otway Santos (BOL) ✱ / Beach Petroleum

EXPLORATION PERMITS BASIN TENEMENT HOLDER EXPIRY DATE

PEP 152 Otway Origin ✱/ Lakes Oil/ Essential Petroleum 03/02/2005 PEP 153 Otway Santos ✱ 28/02/2005 PEP 154 (a) (b) Otway Santos ✱/ Beach Petroleum 31/03/2005 PEP 155 Gippsland Petrotech ✱ 28/08/2005 PEP 156, 157 Gippsland Petrotech ✱ 16/06/2005 PEP 158 Gippsland Petrotech ✱ 16/03/2005 PEP 159 Otway Origin ✱/ Essential Petroleum 12/11/2005 PEP 160 Otway TMOC Exploration ✱/ Origin 13/11/2005 PEP 161 Murray Knight Industries 18/02/2005 PEP 1622002 Gippsland Bass Petroleum 15/05/2006

✱ OPERATOR

20 PESA News April/May 2002 EXPLORATION ACTIVITIES