PETROLEUM GEOCHEMISTRY OF THE OTWAY BASIN AND THE SIGNIFICANCE OF COASTAL

BITUMEN STRANDINGS ON ADJACENT SOUTHERN AUSTRALIAN BEACHES

byDIANNE PADLEY

M.Sc. Organic Geochemistry and Organic Petrology,B.Sc. Hons. Geology, Newcastle upon Tyne, U.K.

Volume 1

Thesis submitted for the degree of Doctor of Philosophy

inThe University of Adelaide

Faculty of Science, Department of Geology and Geophysics

August 1995

To my grandad, Alfred Partridgefor bicycles, dominoes and

wisdom - life is long

This work contains no material which has been accepted for the award of any other degree or diploma in any university or other tertiary institution and, to the best of my knowledge and belief, contains no material previously published or written by another person, except where due reference has been made in the text.

I give consent to this copy of my thesis, when deposited in the University Library, being available for loan and photocopying.

SIGNED: ..................... DATE: ....................

i

Abstract

The stranding of crude oil on the beaches of southern Australia was fi rst recorded approximately 150 years ago. This material, locally known as coastal bitumen, was used by the early maritime visitors and settlers to caulk their vessels and is the fi rst recorded commercial use of crude oil in Australia. Historical records indicate that the greatest amount of coastal bitumen strands along the coasts of South Australia and western Victoria. The Otway Basin, which straddles part of this shoreline, is one of a series of basins located along the southern passive margin of the Australian continent. These basins formed during the Late Jurassic-Early Cretaceous in response to the rifting and fi nal breakup of eastern Gondwanaland 95 million years ago. The circumstantial evidence of coastal bitumen, and the more recent discovery of offshore gas seeps, have been used to promote petroleum exploration in the Otway Basin. As a result, several small but commercial gas fi elds and numerous oil shows have been discovered. The moderate success of exploration in the Otway Basin may not be a true indication of its ultimate reserves, given that Australia’s most prolifi c petroleum province, the Gippsland Basin, lies immediately to the east.

The aims of this study were twofold: to appraise the hydrocarbon potential of the western Otway Basin, and to identify the origin(s) of the coastal bitumen.

Source rocks were identifi ed using an interdisciplinary approach which included wireline log interpretation, lithological descriptions, organic petrology (viz. maceral analysis, vitrinite refl ectance) and organic geochemical analyses (viz. TOC and Rock-Eval pyrolysis). Oil-source rock and oil-oil correlations were attempted using carbon isotope mass spectrometry, gas chromatography and gas chromatography-mass spectrometry.

In the western Otway Basin the most important hydrocarbon plays occur within the Early Cretaceous Otway Group (Crayfi sh Subgroup and Eumeralla Formation). Terrigenous source rocks with potential to generate both oil and gas were identifi ed in the lower Eumeralla Formation. The waxy paraffi nic-naphthenic crude oils recovered from Windermere-1 and 2, Lindon-1 and Port Campbell-4 have biomarker signatures that are indicative of a terrestrial source to which conifer resins made a signifi cant contribution. These oils have been correlated with coaly facies of the lower Eumeralla Formation. In the Crayfi sh Subgroup, lacustrine mudstones in the Pretty Hill Sandstone contain kerogen derived from a mixture of algal and biodegraded plant remains which appears to have generated signifi cant volumes of gas (Katnook-Ladbroke Grove Gas Field; Troas-1) and minor quantities of oil (Sawpit-1).

Reservoir bitumens occur in the Pretty Hill Sandstone at Crayfi sh-A1 and Zema-1. These bitumens are unlike any other oil found within the Otway Basin. Their distinctive biomarker assemblage indicates that they were derived from algal and bacterial remains preserved in carbonate-evaporite sediments. Although no such source rocks have yet been penetrated by any exploration well, it is believed that they may be located within either the lower Crayfi sh Subgroup or the Casterton beds. These inferred source rocks are likely to be overmature in most areas of the western Otway Basin, precluding any signifi cant future hydrocarbon generation. However, their required presence indicates that hydrocarbons were generated very early in the history of the basin.

ii

A bimonthly survey documenting the stranding of coastal bitumen between Kangaroo Island, South Australia and Cape Otway, Victoria was carried out from September 1990 to September 1991. The physical characteristics of the coastal bitumens collected during this period enabled three categories of beached petroleum to be identifi ed: waxy bitumen, asphaltite and oil slicks. Elemental, isotopic and biomarker analyses of representative samples confi rmed that these three categories of petroleum are not geochemically related. Of extreme signifi cance is the fact that they bear no resemblance to oil discoveries in the Otway Basin.

Waxy bitumens are the most common type of coastal bitumen, accounting for 90 % of the total beached petroleum. They represent the weathered remains of paraffi nic-naphthenic crude oils which have low to moderate sulphur (0.1-2.6 %) contents. Their medium to low density (10-40 °API) ensures that they fl oat in sea water. These waxy bitumens contain a unique association of source-specifi c biomarkers, notably botryococcane, oleanane, isomeric bicadinanes and 4-methyl steranes, which is not found in any indigenous Australian oils. The biological precursor of botryococcane is synthesized only by the freshwater green alga Botryococcus sp. and 4-methyl sterols are abundant in dinofl agellates. Oleanane originates from angiosperms which fi rst appeared in the Late Cretaceous. High concentrations of bicadinane are derived from the resins (dammars) of the fossil angiosperm family Dipterocarpaceae. In terms of their biogeographic range, both extant and fossil dipterocarps are confi ned to the tropics of Southeast Asia, although their dammars have been found on South Australian beaches. Together, these biomarkers imply that the waxy bitumens were derived from Tertiary lacustrine source beds which were deposited at low palaeolatitudes. When the effects of extensive weathering and biodegradation are taken into account, the waxy bitumens are similar to bitumens stranded on the coasts of the Northern Territory and Western Australia, and to Tertiary crude oils produced from Sumatra. Hence, it has been deduced that the waxy bitumens originate from oil seeps within the Indonesian Archipelago. These crude oils are transported into southern Australian waters as fl otsam by a complex system of surface ocean currents which include the South Equatorial Current, Leeuwin Current and West Wind Drift.

Asphaltite is the least common variety of coastal bitumen. These jet black bitumens are heavy (~ 8 °API) and characteristically exhibit deep desiccation cracks on their upper surface. The oldest asphaltite analysed in this study was collected before the year 1900 on Kangaroo Island, and the stranding of comparable samples continues to the present day. The asphaltites have a uniform aromatic-asphaltic composition and are rich in sulphur (S = 3-6 %). Their unimodal n-alkane distribution centred about C15, the predominance of cholestane among their C27-C29 desmethyl steranes and the presence of dinosterane (a marine dinofl agellate biomarker) as the major C30 4-methyl sterane, highlight the marine source affi nity of the asphaltites. The presence of rearranged steranes and hopanes indicates that their parent crude oils were generated from clay-rich sediments. The asphaltite samples are isotopically light (δ13Csat ~ -30.0 ‰; sat ~ -30.0 ‰; sat δ13Carom ~ -29.5 ‰) relative to the waxy bitumens. These depleted δ13C values, combined with the presence of dinosterane and C28/C29 sterane ratios ranging from 0.7 to 1.2, suggests that their source rocks are of Mesozoic age. The South Australian and Victorian asphaltites are almost identical to asphaltic bitumen which strands on the west and south coasts of Tasmania. The biomarker geochemistry of the asphaltite was compared with those of many other Australian and non-Australian marine sediments and oils. However,

iii

no matching signatures were found and so the source of the asphaltite could not be identifi ed. Nevertheless, the long stranding history of the asphaltite suggests that it is a natural phenomenon.

A third group of ‘coastal bitumens’ represents stranded oil slicks. These fi lms and sheets of liquid oil are of sporadic occurrence and have been linked to local maritime operations. The bitumens assigned to this category have variable geochemical signatures depending on the type of oil discharged; both refi ned and unrefi ned crude oils were among the samples collected. The majority of these crude oils originated from either Southeast Asia or the Middle East, the two main provinces from which oil is imported into Australia.

The stranding of coastal bitumen along the southern margin of Australia can be attributed to both natural and anthropogenic causes but not, as fi rst suspected, to oil seepage from the offshore sector of the Otway Basin.

iv

v

Acknowledgements

This research project was carried out under the supervision of Dr David M. McKirdy, to whom I am indebted for his constant support and painstaking concern for my well-being. Thank you.

I would like to express my gratitude to Dr Roger E. Summons and Andrew P. Murray (Australian Geological Survey Organisation, Canberra) for their hospitality, encouragement, and help with the acquisition and interpretation of MRM data. I also extend my thanks to Dr Chris J. Boreham for undertaking HPLC analyses on selected aromatic and resin fractions.

I wish to thank Dr Robb J. Willink and Neil P. Tupper (SAGASCO Resources Ltd.) and Dr. David I. Gravestock (Department of Mines and Energy, South Australia) for their guidance throughout the project.

Special thanks are due to my colleague Bernd H. Michaelsen. It was only by working together that we were able to furnish, equip and run the Organic Geochemistry Laboratory in the Department of Geology and Geophysics, University of Adelaide. I thank Rick Barrett and Sherry Proferes for their help with photography and computer drafting. Also to Don R. Vinall for his assistance with coastal bitumen collecting, vehicle maintenance and off-road driving lessons.

Technical assistance was provided by Dr Graeme Currie and Yoji Hayasaka (GC-MS facility, Australian Wine Research Institute, Adelaide), Xu Gu and Libby Geary (Adelaide University) and Janet Hope and Zoltan Horvath (Australian Geological Survey Organisation, Canberra).

I also extend my thanks to all of the following for helping me to complete this comprehensive study:

Geoff Wood (SANTOS Ltd.) and Dr Roger Morgan (Morgan Palaeo Associates) for their palynological expertise;

David N. Love (Department of Mines and Energy, South Australia) for information on seismic activity;

Dr John B. Jones (Adelaide University) for help with the interpretation of XRF data on pumice samples;

Dr Steve J. Rowland and David Heath (University of Plymouth, UK) for acquiring high temperature gas chromatograms;

Dr Michael A. Wilson (Division of Coal and Energy Technology, CISRO) for n.m.r. spectra;

Alan Aldrige (Database, UK) for consultation on isotopic procedures;

Dr John A. T. Bye (Flinders University), Dr Ross W. Griffi ths and Dr Nigel Wace (Australian National University) for discussions on oceanography;

vi

Brian L. Watson (AMDEL Core Services, Adelaide) for allowing me access to the Leitz microscope for vitrinite refl ectance measurements;

South Australian Department of Mines and Energy, SAGASCO Resources Ltd., Oil Company of Australia N.L. and BHP Petroleum Pty. Ltd. for providing samples from exploration wells;

Australian Geological Survey Organisation for supplying samples from RV Rig Seismic Cruise 102;

Roger Sweeney and Tony Ralph (Port Stanvac Refi nery) for crude oil samples; Dr Bill Birch (Museum of Victoria) and Gerr Horr (South Australian Museum) who donated samples of archived coastal bitumen and amber; and

the Sykes family from Port Fairy who monitored the stranding of bitumen on the beach opposite Lake Yambuk.

Funding for this project was provided by:

University of Adelaide Research Grants;

Australian Research Council;

SAGASCO Resources Ltd.;

South Australian Department of Mines and Energy;

Mobil Exploration Australia Pty. Ltd.; and

BHP Petroleum Pty. Ltd.

I also acknowledge receipt of a Postgraduate Research Scholarship from the University of Adelaide.

Permission to sample in National Parks and Conservation areas was granted by the National Parks and Wildlife Service (Permit No. U20302) and Victorian Department of Conservation and Environment Research (Permit No. 901/001).

Finally, I would like to thank my family and my fi ancé Drue Saint Edwards for enduring our separation and for their faith in me.

“Love is temporary insanity curable by marriage”

Amba Bierce

But I’ll wait and see...............................

vii

Contents

Abstract i

Acknowledgements ........................................................................................................... v

Chapter 1 Introduction .................................................................................................... 31.1 Preamble ........................................................................................................ 31.2 Aims ............................................................................................................... 31.3 Coastal Bitumen ............................................................................................. 4

1.3.1 History of Stranding ......................................................................... 41.3.2 Defi nition and Descriptions ............................................................. 61.3.3 Theories for the Origin of Coastal Bitumen .................................... 61.3.4. Local (Otway Basin) Submarine Oil Seeps ..................................... 81.3.5. Distant Submarine Oil Seeps ......................................................... 12

1.4 The Otway Basin .......................................................................................... 131.4.1 Geological Setting .......................................................................... 131.4.2 Tectonic Evolution ......................................................................... 131.4.3 Stratigraphy .................................................................................... 161.4.4 Structure ......................................................................................... 191.4.5 Continental Drift and Palaeoclimate .............................................. 221.4.7 History of Petroleum Exploration ................................................. 231.4.8 Exploration Wells, Permits and Hydrocarbon Discoveries ............ 281.4.9 Source and Reservoir Rocks .......................................................... 29

Chapter 2 The Study of Sedimentary Organic Matter ....................................................The Study of Sedimentary Organic Matter ....................................................The Study of Sedimentary Organic Matter 332.1 Kerogen ........................................................................................................ 33

2.1.1. Organic Petrological Description of the Maceral Groups .............. 332.1.2 Microlithotypes .............................................................................. 342.1.3 Coalifi cation ................................................................................... 342.1.4 Vitrinite Refl ectance ...................................................................... 352.1.5 Kerogen Typing ............................................................................. 362.1.6 TOC and Rock-Eval Pyrolysis ....................................................... 362.1.7 Generation of Petroleum ................................................................ 382.1.8 Elemental Analysis ........................................................................ 42

2.2 Biomarkers ................................................................................................... 422.2.1 Defi nition of a Biomarker ..............................................................2.2.1 Defi nition of a Biomarker ..............................................................2.2.1 Defi nition of a Biomarker 422.2.2 n-Alkanes ....................................................................................... 432.2.3 Acyclic Isoprenoid Alkanes ........................................................... 492.2.4 Bicyclic Sesquiterpanes ................................................................. 502.2.5 Diterpanes ...................................................................................... 502.2.6 Steranes .......................................................................................... 512.2.7 Hopanes and Moretanes ................................................................. 572.2.8 Gammacerane ................................................................................ 602.2.9 Oleanane ........................................................................................ 612.2.10 Bicadinanes .................................................................................... 622.2.11 Aromatic Hydrocarbons:Alkylphenanthrenes ............................... 632.2.12 Molecular Maturity Parameters ..................................................... 63

2.3 Stable Carbon Isotopes ................................................................................ 66

viii

Chapter 3 Analytical Procedures .................................................................................... 713.1 Sampling ...................................................................................................... 71

3.1.1 Cores and Cuttings from the Otway Basin .................................... 713.1.2 Hydrocarbons of the Otway Basin ................................................. 713.1.3 Coastal Bitumens ........................................................................... 713.1.4 Dredge Samples from the Ceduna Sub-basin ................................ 723.1.5 Miscellaneous Crude Oil and Source Rock Samples ..................... 723.1.6 Coastal Amber and Coastal Pumice ............................................... 73

3.2 Preparation of Samples ................................................................................ 733.2.1 Core and Cuttings .......................................................................... 733.2.2 Coastal Bitumens ........................................................................... 73

3.3 Organic Petrology ........................................................................................ 733.3.1 Refl ected Light Microscopy ........................................................... 733.3.2 Fluorescence Microscopy .............................................................. 743.3.3 Maceral Analysis ............................................................................ 743.3.4 Vitrinite Refl ectance Measurement ................................................3.3.4 Vitrinite Refl ectance Measurement ................................................3.3.4 Vitrinite Refl ectance Measurement 74

3.4 Organic Geochemistry of Sediments, Oils and Coastal Bitumens ............... 743.4.1 Elemental Analysis ........................................................................ 743.4.2 Total Organic Carbon Analysis ...................................................... 753.4.3 Rock-Eval Pyrolysis ...................................................................... 753.4.4 Solvent Extraction .......................................................................... 753.4.5 De-asphaltening ............................................................................. 753.4.6 Liquid Chromatography ................................................................. 763.4.7 Thin Layer Chromatography (TLC) .............................................. 763.4.8 Urea Adduction .............................................................................. 763.4.9 Gas Chromatography (GC) ............................................................ 773.4.10 High Temperature-Gas Chromatography (HT-GC) ....................... 773.4.11 Gas Chromatography-Mass Spectrometry (GC-MS) ................... 773.4.12 Stable Carbon Isotope Mass Spectrometry .................................... 78

3.5 Organic Geochemistry of Coastal Ambers ................................................... 783.5.1 Pyrolysis ......................................................................................... 783.5.2 Liquid Chromatography ................................................................. 793.5.3 Stable Carbon Isotopic Composition of Coastal Ambers,

Resinites and Resins ...................................................................... 793.5.4 Pyrolysis-Gas Chromatography (Py-GC) ...................................... 79

3.6 Palynology of Coastal Bitumens .................................................................. 793.7 Petrology and Geochemistry of Coastal Pumice .......................................... 80

3.7.1 Petrology ........................................................................................ 803.7.2 Geochemistry ................................................................................. 80

Chapter 4 The Stranding Of Coastal Bitumen On Southern Australian Beaches ........... 834.1 Coastal Bitumen Monitoring Programs ....................................................... 83

4.1.1 Previous Work ................................................................................4.1.1 Previous Work ................................................................................4.1.1 Previous Work 834.1.2 The 1990-1991 Coastal Bitumen Survey ....................................... 83

4.2 Description, Location and Abundance of Coastal Bitumen ......................... 864.2.1 Introduction .................................................................................... 864.2.2 Coastal Bitumen Types .................................................................. 864.2.3 Waxy Bitumen and Weathered Waxy Bitumen .............................. 874.2.4 Asphaltite ....................................................................................... 99

ix

4.2.5 Oil Slicks ...................................................................................... 1044.2.6 Wax .............................................................................................. 109

4.3 Miscellaneous Flotsam .............................................................................. 1094.3.1 Animal Faeces .............................................................................. 1094.3.2 Coal .............................................................................................. 1094.3.3 Amber ..........................................................................................4.3.3 Amber ..........................................................................................4.3.3 Amber 1104.3.4 Pumice ..........................................................................................1114.3.5 Algal Blooms ................................................................................1114.3.6 Marine Turtles .............................................................................. 1124.3.7 Man-made Ocean Flotsam ........................................................... 112

4.4 The Oceanography of Local Southern Australian Waters .......................... 1134.5 Summary .................................................................................................... 116

Chapter 5 Hydrocarbon Potential Of The Western Otway Basin ................................. 1215.1 Source-Rock Analyses ............................................................................... 121

5.1.1 Previous Studies ........................................................................... 1215.1.2 Wells Sampled .............................................................................5.1.2 Wells Sampled .............................................................................5.1.2 Wells Sampled 1225.1.3 Interpretation of Source Rock Data ............................................. 1235.1.4 Summary: Western Otway Basin ................................................. 137

5.2 Eumeralla Formation Source Play on the Chama Terrace, Offshore Western Otway Basin ................................................................................. 1385.2.1 Source Rock Analysis Geltwood Beach-1 ................................... 1415.2.2 Source Rock Analysis Chama-1A ................................................5.2.2 Source Rock Analysis Chama-1A ................................................5.2.2 Source Rock Analysis Chama-1A 1465.2.3 Source Rock Analysis Crayfi sh-A1 ............................................. 1495.2.4 Source Rock Analysis Troas-1 (Confi dential) ............................. 1555.2.5 Source Rock Analysis Mocamboro-11 (Confi dential) ................. 1565.2.6 Summary ...................................................................................... 158

Chapter 6 Hydrocarbon Geochemistry Of The Western Otway Basin ......................... 1636.1 Geochemistry of Eumeralla Formation Sediments from the Chama

Terrace ........................................................................................................ 1636.1.1 C. hughesi Coaly Facies .............................................................. 1636.1.2 C. striatus Lacustrine Facies ....................................................... 1746.1.3 Lower Eumeralla Formation at Troas-1 (Confi dential) ............... 1776.1.4 Carbon Isotopic Composition of the Lower Eumeralla

Formation ..................................................................................... 1826.1.5 Depositional Environment of the Lower Eumeralla Formation .. 1826.1.6 Oil Source Potential of the Lower Eumeralla Formation ............ 185

6.2 Geochemistry of Crude Oils, Condensates and Oil Shows ........................ 1856.2.1 Oils and Condensates Reservoired in the Pebble Point

Formation, Wangerrip Group (Lindon-1, Wilson-1) .................... 1866.2.2 Oils and Condensates Reservoired in the Waarre Sandstone,

Sherbrook Group (Caroline-1, North Paaratte-2) ........................ 1916.2.3 Oils and Condensates Reservoired in the Otway Group ............. 1956.2.4 Oil Reservoired in Fractured Basement at Sawpit-1

(Confi dential) ............................................................................... 2016.3 Geochemistry of Reservoir Bitumens ........................................................ 203

6.3.1 Crayfi sh-A1: Previous Work ........................................................6.3.1 Crayfi sh-A1: Previous Work ........................................................6.3.1 Crayfi sh-A1: Previous Work 2036.3.2 Crayfi sh-A1: Preliminary Studies ................................................ 204

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6.3.3 Crayfi sh-A1: Reservoir Bitumen Geochemistry .......................... 2086.3.4 Zema-1: Previous Work ...............................................................6.3.4 Zema-1: Previous Work ...............................................................6.3.4 Zema-1: Previous Work 2206.3.5 Zema-1: Oil Show and Reservoir Bitumen Geochemistry .......... 2226.3.6 Discussion: Family A Reservoir Bitumens .................................. 229

6.4 Oil-Oil and Oil-Source Rock Correlations ................................................. 2316.4.1 Oil-Oil Correlations ..................................................................... 2316.4.2 Oil-Source Rock Correlations ...................................................... 234

6.5 Connection Between Earthquakes in the Otway Basin and the Stranding of Coastal Bitumen .................................................................... 238

6.6 Summary .................................................................................................... 240

Chapter 7 Southern Australian Coastal Waxy Bitumen ................................................ 2437.1 Previous Work ............................................................................................7.1 Previous Work ............................................................................................7.1 Previous Work 243

7.1.1 Defi nition of Coastal Bitumen Families 1, 2, 3 and 4 (after McKirdy, 1984a) .......................................................................... 243

7.2 Organic Geochemistry of Coastal Waxy Bitumen ..................................... 2447.2.1 General Organic Geochemistry .................................................... 2447.2.2 Molecular Signatures of Waxy Bitumen Families ....................... 2517.2.3 Source Character of Waxy Bitumens ........................................... 2687.2.4 Weathering Characteristics .......................................................... 2697.2.5 Maturity ....................................................................................... 2747.2.6 Variation of Bulk Composition with Stranding Location ............ 2747.2.7 Historical Continuity of Stranding ............................................... 2777.2.8 Summary ...................................................................................... 283

7.3 Palynology of Selected Coastal Bitumens ................................................. 2837.3.1 Introduction .................................................................................. 2837.3.2 Results and Discussion ................................................................ 283

7.4 Origin of Southern Australian Waxy Bitumen .......................................... 2847.4.1 Evidence Against a Southern Australian Origin .......................... 2847.4.2 Evidence for an Indonesian Origin .............................................. 2857.4.3 The Occurrence of Southeast Asian Oils in Southern Australia .. 2937.4.4 Evidence for Southern Australian Coastal Waxy Bitumens

being Southeast Asian Ocean Flotsam ......................................... 2937.5 Coastal Bitumen from the Seychelle Islands ............................................. 300

7.5.1 Group 1 Seychelles Coastal Bitumen .......................................... 3007.5.2 Group 2 Seychelle Islands Coastal Waxy Bitumen ..................... 3057.5.3 Discussion .................................................................................... 305

7.6 Summary .................................................................................................... 305

Chapter 8 Southern Australian Coastal Asphaltite ....................................................... 3118.1 Organic Geochemistry of Coastal Asphaltite ............................................. 311

8.1.1 Bulk Composition ........................................................................ 3118.1.2 Molecular Signatures ................................................................... 3118.1.3 Molecular Weathering Characteristics ......................................... 3188.1.4 Maturity ....................................................................................... 3188.1.5 Age of Source Rocks ................................................................... 3238.1.6 Atypical Asphaltite Samples ........................................................ 3258.1.7 Molecular Signatures of Southern Australian Asphaltites

over Time ..................................................................................... 3268.1.8 Summary ...................................................................................... 328

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8.2 Palynological Analyses .............................................................................. 3288.3 Origin of the Southern Australian Coastal Asphaltites .............................. 328

8.3.1 Mode of Asphaltite Formation ..................................................... 3288.3.2 Evidence Against a Southern Australian Origin (Otway

Basin, Duntroon Basin, Ceduna Sub-basin) ................................ 3308.3.3 Evidence for a Distant Origin ...................................................... 3348.3.4 Evidence for an Anthropogenic Origin ........................................ 344

8.4 Summary .................................................................................................... 344

Chapter 9 Southern Australian Oil Slicks ..................................................................... 3479.1 Imported Petroleum Feedstocks ................................................................. 3479.2 Geochemistry of Oil Slicks ........................................................................ 348

9.2.1 Kangaroo Island Oil Slick, December 1986 ................................ 3489.2.2 Little Dip Conservation Park-Nora Creina Bay Oil Slick,

January 1993 ................................................................................ 3489.2.3 Cape Otway Oil Slick, May 1990 ................................................ 3599.2.4 Little Dip Conservation Park-Robe Oil Slick, November 1990 .. 3619.2.5 Greasy Bitumen, September-October 1991 ................................. 3649.2.6 Miscellaneous Oils ....................................................................... 3689.2.7 Coastal Waxes .............................................................................. 370

9.3 Summary .................................................................................................... 370

Chapter 10 Conclusions ................................................................................................ 375

Epilogue .................................................................................................................... 379

Bibliography ................................................................................................................. 381

Appendix 1 Well And Sample Information ................................................................. 431A1.1 Well Information ........................................................................................ 431A1.2 Sample Information ................................................................................... 439

Appendix 2 Analytical Methods .................................................................................. 449A2.1 Sample Preparation .................................................................................... 449

A2.1.1 Preparation of Cuttings Samples .................................................. 449A2.1.2 Preparation of Core Samples ....................................................... 449A2.1.3 Preparation of Samples for Organic Geochemical Analyses ....... 450

A2.2 Instrument Parameters ................................................................................ 451A2.2.1 Gas Chromatography ................................................................... 451A2.2.2 High Temperature Gas Chromatography ..................................... 452A2.2.3 Gas Chromatography-Mass Spectrometry ................................... 452

A2.3 Carbon Isotope Standards .......................................................................... 455

Appendix 3 Stranding Locations Of Coastal Bitumen And Coastal Amber ................Stranding Locations Of Coastal Bitumen And Coastal Amber ................Stranding Locations Of Coastal Bitumen And Coastal Amber 459A3.1 Historical Occurrences of Stranded Coastal Bitumen, Coastal

Amber and Algal Blooms. .......................................................................... 459A3.2 Catalogue of Coastal Bitumen and Coastal Amber Samples Collected

on the Beaches of Southern Australia. ....................................................... 465A3.3 Locations of Samples Collected During the Bi-monthly Coastal

Bitumen Survey, 1990-1991 (microfi che). ................................................. 487

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A3.4 Summary Maps Showing Where Stranded Coastal Bitumen and Coastal Amber Samples were Collected During the Coastal Bitumen Survey, 1990-1991. ..................................................................... 488

Appendix 4 Rock-eval Pyrolysis Data ......................................................................... 497A4.1 Rock-Eval Pyrolysis Data, Western Otway Basin ..................................... 497

A4.1.1 Open File Rock-Eval Pyrolysis Data (Microfi che) ...................... 497A4.1.2 Confi dential Rock-Eval Pyrolysis Data (Microfi che) .................. 497A4.1.3 Bibliography to Rock-Eval Pyrolysis Data .................................. 498

A4.2 Rock-Eval Pyrolysis Data of the Potoroo Formation, Ceduna Sub-basin .................................................................................................... 501

Appendix 5 Organic Petrology .................................................................................... 505A5.1 Petrological Information ............................................................................ 505

A5.1.1 Glossary ....................................................................................... 505A5.1.2 Key to Petrological Descriptions ................................................. 508

A5.2 Organic Petrological Descriptions: Western Otway Basin ........................ 509A5.2.1 Casterton-1 ................................................................................... 509A5.2.2 Chama-1A ....................................................................................A5.2.2 Chama-1A ....................................................................................A5.2.2 Chama-1A 512A5.2.3 Crayfi sh-A1 .................................................................................. 521A5.2.4 Geltwood Beach-1 ....................................................................... 521A5.2.5 Mocamboro-11 ............................................................................. 528A5.2.6 Morum-1 ...................................................................................... 531A5.2.7 Troas-1 ......................................................................................... 532

A5.3 Organic Petrological Descriptions: Miscellaneous Samples ..................... 536A5.3.1 Sumatran Source Rock .................................................................A5.3.1 Sumatran Source Rock .................................................................A5.3.1 Sumatran Source Rock 536A5.3.2 New Zealand Source Rocks ......................................................... 536A5.3.3 R/V Rig Seismic Cruise 102: Ceduna Sub-basin ......................... 537

A5.4 Maceral Analyses ....................................................................................... 539A5.4.1 Geltwood Beach-1 ....................................................................... 539A5.4.2Chama-1A .......................................................................................A5.4.2Chama-1A .......................................................................................A5.4.2Chama-1A 548A5.4.3 Mocamboro-11 ............................................................................. 564

A5.5 Vitrinite Refl ectance Data .......................................................................... 572A5.5.1 Chama-1A ....................................................................................A5.5.1 Chama-1A ....................................................................................A5.5.1 Chama-1A 572A5.5.2 Mocamboro-11 ............................................................................. 581

Appendix 6 Coastal Bitumen Geochemical Data ........................................................ 589A6.1 Compilation of Coastal Bitumen Geochemical Data. ................................ 589

Appendix 7 Reports, Published Abstracts And Papers ................................................ 601A7.1 Reports ....................................................................................................... 601A7.2 Published Abstracts .................................................................................... 602A7.3 Published Papers ........................................................................................ 603

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List of Figures

Figure 1.1 Historical coastal bitumen stranding sites around the Australian coast. ..5

Figure 1.2 Location of the Otway Basin ....................................................................9

Figure 1.3 Structural elements of the Otway Basin (modifi ed from Williamson et al., 1987 and Robertson et. al., 1988). ...............................................15

Figure 1.4 Stratigraphy of the western Otway Basin (modifi ed from Morton, 991). .......................................................................................................16

Figure 1.5 Schematic cross section of the western Otway Basin (modifi ed from Gravestock et al., 1986). ........................................................................18

Figure 1.6 Time structure mape at base Aptian unconformity level, western Otway Basin. ..........................................................................................21

Figure 1.7 Petroleum exploration licence areas in the Otay Basin up to December 1993. .....................................................................................24

Figure 1.8 Petroleum exploration wells drilled in the Otway Basin up to December 1993. .....................................................................................25

Figure 2.1 Coal microlithotype classifi cation. .........................................................35

Figure 2.2 Van Drevelen diagram showing the principal types and evolution paths of kerogen (after Tissot and Welte, 1984). ....................................37

Figure 2.3 Hydrocarbon-generation models from different kerogen types (after Powell and Snowdon, 1983). ........................................................41

Figure 2.4 Structures of isoprenoid ikanes. .............................................................48

Figure 2.5 Structures of bicyclic sesquiterpanes. ....................................................49

Figure 2.6 Stuctures of diterpanes. ..........................................................................51

Figure 2.7 Numbering system for steranes ..............................................................52

Figure 2.8 The principal isomerisation of 5α(H),14α(H),17α(H) 20R C29steranes which occurs with increasing maturity (after Seifert and Moldowan, 1981). ..................................................................................53

Figure 2.9 Structures of selected steranes. ..............................................................55

Figure 2.10 Numbering system of hopanes. ..............................................................57

Figure 2.11 Structures of selected triterpanes based on the hopane skeleton. ...........58

Figure 2.12 Structures of selected triterpanes ...........................................................62

Figure 2.13 Numbering system of alkylphenanthrenes .............................................62

Figure 4.1 The 1990–1991 Coast Bitumen Survey area ..........................................85

xiv

Figure 4.3 Waxy bitumens collected along the southern Australian coast, September– October 1990. .....................................................................91

Figure 4.4 Waxy bitumens collected along the southern Australian coast, September 1991. .....................................................................................92

Figure 4.5 Abundances of waxy bitumen collected from 200m beach at selected sites during the 1990–1991 Coastal Bitumen Survey. ...........................93

Figure 4.6 Stranding locations of asphaltite during 1990–1991. ...........................101

Figure 4.7 Asphaltites collected along the southern Australian coast, September 1990–1991. .........................................................................102

Figure 4.8 Stranding locations of major oil slicks during 1986–1993. .................105

Figure 4.9 Local surface currents along the coast of southeaster South Australia and western Victoria. ............................................................................117

Figure 5.1 Rock-Eval pyrolysis data for the Dilwyn Formation, western Otway Basin. ........................................................................................125

Figure 5.2 Rock-Eval pyrolysis data for the Paaratte Formation and Timboon Sandstone, western Otway Basin. ........................................................125

Figure 5.3 Rock-Eval pyrolysis data for the Belfast Mudstone, western Otway Basin. ........................................................................................127

Figure 5.4 Rock-Eval pyrolysis data for the Belfast Mudstone at Triton-1, eastern offshore Otway Basin. .............................................................127

Figure 5.5a Rock-Eval pyrolysis data for the Sherbrook Group in the Gambier Embayment. .........................................................................................129

Figure 5.5b Rock-Eval pyrolysis data for the Shebrook Group on the offshore Crayfi sh Platform and in the western Voluta Trough. ..........................129

Figure 5,6a Rock-Eval pyrolysis data for the upper Otway Group in the and Gambier Embayment and Robe and Penola Troughs. .........................131

Figure 5.6b Rock-Eval pyrolysis data for the upper Otway Group on the offshore Crayfi sh Platform. ................................................................................131

Figure 5.7 Rock-Eval pyrolysis data for the Laira Formation, western Otway Basin. ........................................................................................133

Figure 5.8 Rock-Eval pyrolysis data for the Pretty Hill Sandstone, western Otway Basin. ........................................................................................133

Figure 5.9 Rock-Eval pyrolysis data for the Basal Unit in the Penola Trough. ....135

Figure 5.10a Rock-Eval pyrolysis data for the Crayfi sh Subgroup in the Robe and Penola Trough. .....................................................................................136

Figure 5.10b Rock-Eval pyrolysis data for the Crayfi sh Subgroup on the offshore Crayfi sh Platforms. ................................................................136

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Figure 5.11 Rock-Eval pyrolysis data for the Casterton beds in the Penola Trough. .....................................................................................135

Figure 5.12 Source rock development within the lower Eumeralla Formation on the Chama Terrace, western Otway Basin. .....................................139

Figure 5.13 Vitrinite refl ectance versus depth in key wells on the Chama Terrace ..................................................................................................142

Figure 5.14a Rock-Eval pyrolysis data, Eumeralla Formation, Geltwood Beach-1. ...............................................................................................143

Figure 5.14b Rock-Eval pyrolysis data, C.striatus and C. hughesi organic facies, Geltwood Beach-1. ...................................................................143

Figure 5.15a Rock-Eval pyrolysis data, Eumeralla Formation, Chama-1A. .............148

Figure 5.15b Rock-Eval pyrolysis data, C. striatus and C. hughesi organic facies in Chama-1A. .......................................................................................148

Figure 5.16 Rock-Eval pyrolysis data, Eumeralla Formation, Crayfi sh-A1. ..........153

Figure 5.17 Rock-Eval pyrolysis data, Pretty Hill Sandstone, Crayfi sh-A1. ..........153

Figure 5.18 Rock-Eval pyrolysis data for whole rock and solvent extracted samples, Crayfi sh-A1. ..........................................................................154

Figure 5.19 Rock-Eval pyrolysis data, Eumeralla Formation, Troas-1. ..................157

Figure 5.20 Rock-Eval pyrolysis data, Eumeralla Formation, Mocamboro-11. .....157

Figure 6.1 Saturates chromatograms of selected lower Eumeralla Formation source rocks. .........................................................................................167

Figure 6.2 MRM GC-MS chromatograms showing the distribution of steranes and triterpanes C. striatus Lacustrine Facies, sample A923.165/7 (2929-2935 m), Geltwood Beach-1. .....................................................176

Figure 6.3 Saturated chromatograms of selected lower Eumeralla Formation source rocks from Troas-1. ...................................................................179

Figure 6.4 MRM GC-MS chromatograms comparing the distribution of steranes in shaly coal and mudstone at Troas-1. ..................................180

Figure 6.5 Carbon isotopic composition of Otway Basin extracts, oils and reservoir bitumens. ...............................................................................184

Figure 6.6 Bulk composition of Otway Basin oils and reservoir bitumens. ..........184

Figure 6.7 Saturates chromatograms of selected crude oils from the Otway Basin. ....................................................................................................189

Figure 6.8 MRM GC-MS chromatograms showing the distribution of steranes and triterpanes in Windermere-1 crude oil. ..........................................196

Figure 6.9 Saturates chromatograms of selected condensates and crude oils from the Otway basin. ..........................................................................198

xvi

Figure 6.10 MRM GC-MS chromatograms showing the distribution of steranes and triterpanes in Troas-1 condensate, sample A923.233 (2698 m). ...200

Figure 6.11 MRM GC-MS chromatograms showing the distribution of steranes and triterpanes in Sawpit-1 crude oil, sample A923.213 (2514-2546 m). .....................................................................................202

Figure 6.13 Saturates chromatograms of reservoir bitumens from the Undifferentiated Crayfi sh Subgroup at Crayfi sh-A1. ...........................211

Figure 6.14 MRM GC-MS chromatograms showing the distribution of steranes and triterpanes in Family A reservoir bitumen from 1747-1753 m depth in Crayfi sh-A1. ...........................................................................214

Figure 6.15 Saturates chromatograms showing increasing biodegradation of Family A reservoir bitumen towards the base-Aptian unconformity at Crayfi sh-A1. .....................................................................................216

Figure 6.16 MRM GC-MS chromatograms showing the distribution of steranes and triterpanes in Family B and Family C reservoir bitumens from the Undifferentiated Crayfi sh group at Crayfi sh-A1. ...........................219

Figure 6.17 Saturates chromatograms of representative reservoir bitumens from the Pretty Hill Sandstone at Zema-1. ...................................................226

Figure 6.18 Saturates chromatograms of representative reservoir bitumens from the Pretty Hill Sandstone at Zema-1. ...................................................227

Figure 6.19 Saturates chromatograms of selected Otway Basin oils and soure rock extracts. ........................................................................................237

Figure 6.20 MRM GC-MS chromatograms showing the distribution of steranes and triterpanes in source rock extract, Robertson-1 (1762-1768 m). ...239

Figure 7.1 Bulk composition of coastal waxy bitumens. ......................................250

Figure 7.3 Saturates chromatograms of waxy bitumen families. ..........................257

Figure 7.4 MRM GC-MS chromatograms showing the distribution of steranes and triterpanes in Family 1 waxy bitumen (sample B-38). ..................258

Figure 7.5 MRM GC-MS chromatograms showing the distribution of bicandinane and methylbicadinane in waxy bitumen families. ...........264

Fgure 7.6 MRM GC-MS chromatograms showing the distribution of steranes and triterpanes in Family 2 waxy bitumen (sample CB-28). ...............266

Figure 7.7 MRM GC-MS chromatograms showing the distribution of steranes and triterpanes in Family 4 waxy bitumen (sample CB31). .................267

Figure 7.8 Saturates chromatograms showing weathering profi les in Family 1 and Family 3 waxy bitumens. .............................................................271

Figure 7.9 High temperature saturates chromatograms of waxy bitumens. ..........273

xvii

Figure 7.10 Change in bulk composition of Family 1 waxy bitumens due to weathering. ...........................................................................................277

Figure 7.11 Saturates chromatograms of coastal waxy bitumens showing the similarity of ancient and recently stranded samples. ...........................278

Figure 7.12 Saturates chromatograms of waxy bitumens collected from inland sand dunes and on the beach in Beachport Conservation Park. ...........279

Figure 7.13 Ocean currents (adapted from Hughes and Goodall, 1993). ................280

Figure 7.14 Location of selected sedimentary basins within Indonesia. .................286

Figure 7.15 Saturates chromatograms of Indonesian crude oils and extracts. ........291

Figure 7.16 MRM GC-MS chromatograms showing the distribution of steranes and triterpanes in Minas-1 crude oil. ....................................................292

Figure 7.17 MRM GC-MS chromatograms showing the distribution of bicadinane and methylbicadinane isomers in Southeast Asian crude oils and South Australian coastal waxy bitumens. ............................................294

Figure 7.18 Comparison of saturates chromatograms of representative coastal waxy bitumens from Northern Territory, Western Australia, South Australia and Victoria. .........................................................................296

Figure 7.19 Ocean currents which are responsible for the transportation of fl otsam from southeast Asia to southern Australia. ..............................297

Figure 7.20 Gas chromatograms of aliphatic hydrocarbons of the 300°C pyrolysates of coastal ambers and reference resin and resinite samples (after Murray et al., 1994) ......................................................302

Figure 7.21 Saturates chromatograms of Group 1 coastal bitumen from the Seychelle Islands. .................................................................................304

Figure 7.22 Saturates chromatograms of Group 2 coastal bitumens from the Seychelle Islands and a highly weathered South Australian coastal waxy bitumen. ..........................................................................306

Figure 8.1 Bulk composition of asphaltite. ...........................................................316

Figure 8.2 Saturates chromatograms of typical asphaltites. ..................................317

Figure 8.3 MRM GC-MS chromatograms showing the distribution of steranes and triterpanes in a typical asphaltite (sample CB-32). .......................320

Figure 8.4 Saturates chromatograms of weathered typical asphaltites. .................321

Figure 8.5 Change in the C28/C29 ratio of marine-derived crude oils with time (after Grantham and Wakefi eld, 1988). ................................................324

Figure 8.6 Carbon isotopic composition of coastal asphaltite. ..............................325

Figure 8.7 Change in the carbon isotopic composition of marine crude oils with time (after Chung et al., 1992). ............................................................326

xviii

Figure 8.8 Saturates chromatograms of atypical asphaltites. ................................327

Figure 8.9 Saturates chromatograms of typical asphaltites showing the similarity between old and recent samples. ..........................................................329

Figure 8.10 Stratigraphy of the Bight and Duntroon Basins (after Hibburt, 1992). ...................................................................................................333

Figure 8.11 Saturates chromatograms of selected Potoroo Formation mudstones. .337

Figure 8.12 MRM GCMS chromatograms showing the distribution of steranes and triterpanes in a Potoroo Formation mudstone (sample 102DR003). ..........................................................................................338

Figure 8.13 Saturates chromatograms of asphaltites found stranded around the southern hemisphere. ......................................................................339

Figure 8.14 Saturates chromatograms of selected New Zealand oils and sediments from the East Coast Basin. ..................................................342

Figure 8.15 MRM GC-MS chromatograms showing the distribution of steranes and triterpanes in an oil seep from Waitangi, New Zealand. ...............343

Figure 9.1 Saturates chromatograms of Australian oils used as feed stocks at port Stanvac refi nery. ...........................................................................353

Figure 9.2 Saturates chromatograms of imported oils used as feed stocks at Port Stanvac refi nery. ...........................................................................354

Figure 9.3 Saturates chromatograms of oil slicks with marine carbonate source affi nities. ...............................................................................................357

Figure 9.4 MRM GC-MS chromatograms showing the distribution of steranes and triterpanes in the Kangaroo Island Oil Slick, December,1986 (sample A923.149). ..............................................................................358

Figure 9.5 Saturates chromatograms of the oil slick at Cape Otway in May 1990 and the cargo of the tanker MV Arthur Phillip. ....................................362

Figure 9.6 MRM chromatograms of the oil slick at Cape Otway in May 1990 and the heavy fuel oil from the tanker MV Arthur Phillips. ................363

Figure 9.7 MRM chromatograms showing the distribution of steranes and triterpanes in an oil slick (sample 149) collected from little Dip Conservation Parks in November 1990. ...................................................................................365

Figure 9.8 Bulk composition of coastal bitumen. ..................................................366

Figure 9.9 Carbon isotopic compositions of coastal slicks. ..................................366

Figure 9.10 Saturates chromatograms of coastal greasy bitumn and wax. ..............367

Figure 9.11 MRM chromatograms showing the distribution of steranes and triterpanes in greasy bitumen (sample 373). ........................................369

xix

Figure A3.4.1 93-1000A1 Victoria. Waxy bitumen, oil, asphaltite and amber sample locations. ..............................................................................................488

Figure A3.4.2 93-998 Southeast South Australia. Waxy bitumen sample locations. ..............................................................................................489

Figure A3.4.3 93-997 Southeast South Australia. Oil, asphaltite and amber sample locations. ..............................................................................................490

Figure A3.4.4 93-999 ................ Upper southeast South Australia. Waxy bitumen, oil, asphaltite and amber sample locations. ................................................491

Figure A3.4.5 93-996 Kangaroo Island. Waxy bitumen sample locations. ..............492

Figure A3.4.6 93-995 Kangaroo Island. Oil, asphaltite and amber sample locations. ..............................................................................................493

Figure 4.2.1 Rock-Eval Pyrolysis Data of the Potoroo Formation ...........................501

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List of Tables

Table 1.1 Summary of hydrocarbon and carbon dioxide shows in the Otway Basin. ..........................................................................................26

Table 2.1 Maceral classifi cation scheme (modifi ed from AS 2856-1986). ............34

Table 2.2 Key to Rock-Eval pyrolysis parameters (after Espitalié et al., 1985; Peters, 1986). ..........................................................................................39

Table 2.3 Summary of criteria used to defi ne a mature source rock (after Peters, 1986). .....................................................................................................40

Table 2.4 Key to source-specifi c biomarker parameters. .......................................44

Table 2.5 Key to highly source-specifi c biomarker parameters. ............................45

Table 2.6 Key to labelling on saturated hydrocarbon MRM GC-MS chromatograms. ......................................................................................46

Table 2.7 Key to labelling on aromatic hydrocarbon SIM GC-MS chromatograms. ......................................................................................48

Table 4.1 South Australian beaches monitored in detail for the stranding of coastal bitumen during the 1990-1991 Coastal Bitumen Survey. ..........84

Table 4.2 The total volume of stranded waxy bitumen, weathered waxy bitumen and barnacle bitumen collected at specifi c beaches along the coast of South Australia. ..................................................................84

Table 4.3 Specifi c gravity of coastal ambers. .......................................................110

Table 5.1 Summary of TOC and Rock-Eval pyrolysis data for western Otway Basin. ........................................................................................124

Table 5.2 Summary of Rock-Eval pyrolysis data for individual wells in the Otway Basin. ........................................................................................140

Table 6.1 Quantity and bulk composition of extractable organic matter in the lower Eumeralla Formation on the Chama Terrace. ............................164

Table 6.2 Alkane parameters of sediment extracts from the lower Eumeralla Formation on the Chama Terrace. ........................................................168

Table 6.3 Source-dependent biomarker parameters of sediment extracts from the lower Eumeralla Formation on the Chama Terrace. .......................170

Table 6.4 Maturity-dependent molecular parameters of sediment extracts from the lower Eumeralla Formation on the Chama Terrace. .......................172

Table 6.5 Carbon isotopic compositions of C12+ saturated and aromatic hydrocarbons in Otway Basin extracts, oils and reservoir bitumens. ..183

Table 6.6 Physical properties of Otway Basin oil stains, crude oils and condensates. .........................................................................................187

xxi

Table 6.7 Bulk composition of Otway Basin oil stains, crude oils and condensates. .........................................................................................188

Table 6.8 Alkane parameters of Otway Basin oil stains, crude oils and condensates. .........................................................................................190

Table 6.9 Source-dependent biomarker parameters of Otway Basin oil stains, crude oils and condensates. ..................................................................193

Table 6.10 Maturity-dependent molecular parameters of Otway Basin oil stains, crude oils and condensates. ..................................................................194

Table 6.11 Bulk composition of reservoir bitumens, Crayfi sh-A1. .......................209

Table 6.12 Alkane parameters of reservoir bitumens, Crayfi sh-A1. ......................210

Table 6.13 Source-dependent biomarker parameters of reservoir bitumens, Crayfi sh-A1. .........................................................................................212

Table 6.14 Maturity-dependent molecular parameters of reservoir bitumens, Crayfi sh-A1. .........................................................................................212

Table 6.15 Effects of biodegradation on molecular composition of crude oil (modifi ed from Peters and Moldowan, 1993). .....................................217

Table 6.16 Summary biomarker characteristics of reservoir bitumens in the Pretty Hill Sandstone at Crayfi sh-A1. ..................................................221

Table 6.17 Bulk composition of reservoir bitumens, Zema-1. ...............................223

Table 6.18 Alkane parameters of reservoir bitumens, Zema-1. .............................224

Table 6.19 Source-dependent biomarker parameters of reservoir bitumens, Zema-1. ................................................................................................225

Table 6.20 Maturity-dependent molecular parameters of oil shows and reservoir bitumens, Zema-1. ................................................................................225

Table 6.21 Summary biomarker characteristics of oils reservoired in the Pretty Hill Sandstone at Zema-1. .........................................................230

Table 6.22 Key biomarker characteristics used in oil-oil and oil-source correlations. ..........................................................................................232

Table 6.23 Oil-source correlations in the Otway Basin. ........................................236

Table 7.1 Bulk composition of waxy bitumens. Samples in each family are ordered from least to most weathered. .................................................245

Table 7.2 Extent to which weathering has effected oil composition based on appearance of saturates chromatogram. ...............................................251

Table 7.3 Alkane parameters and isotopic composition of waxy bitumens. Samples in each family are ordered from least to most weathered. .....252

Table 7.4 Source-dependent biomarker parameters of waxy bitumens. ..............259

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Table 7.5 Highly source-specifi c biomarker parameters of waxy bitumens. .......262

Table 7.6 Diagnostic characteristics of Family 1 to 5 waxy bitumens. ...............270

Table 7.7 Maturity-dependent molecular parameters of waxy bitumens. ............275

Table 7.8 Major elemental analyses of coastal pumice samples and reference pumice ..................................................................................................281

Table 7.9 Trace element analyses of coastal pumice samples. ............................281

Table 7.10 Published major element analyses of extrusive rocks from selected orogenic belts. ......................................................................................282

Table 7.11 Published trace element analyses of extrusive rocks from selected orogenic belts. ......................................................................................282

Table 7.12 Palynological analyses of coastal bitumen. ..........................................284

Table 7.13 Bulk composition of Sumatran oils and sediment extracts. .................288

Table 7.14 Alkane parameters of Sumatran oils and sediment extracts. ................288

Table 7.15 Source-dependent biomarker parameters of Indonesian oils and sediment extracts. .................................................................................289

Table 7.16 Highly source-specifi c biomarker parameters of Indonesian oils and sediment extracts. .................................................................................289

Table 7.17 Maturity-dependent biomarker parameters of Indonesian oils and sediment tracts. .....................................................................................289

Table 7.18 Summary of key geochemical parameters used in oil-oil and oil-source rock correlations for the southern Australian coastal waxy bitumens. ..............................................................................................290

Table 7.19 Bulk composition of coastal ambers and reference resin samples. ......301

Table 7.20 Bulk composition of coastal bitumens from the Seychelle Islands. .....303

Table 7.21 Alkane parameters and isotopic composition of coastal bitumens from the Seychelle Islands. ..................................................................303

Table 8.1 Bulk composition of asphaltites. Samples are ordered from least to most weathered. ...................................................................................312

Table 8.1 Bulk composition of asphaltites. Samples are ordered from least to most weathered. ...................................................................................313

Table 8.2 Alkane parameters and isotopic composition of asphaltites. Samples are ordered from least to most weathered. .............................314

Table 8.2 Alkane parameters and isotopic composition of asphaltites. Samples are ordered from least to most weathered. .............................315

Table 8.3 Source-dependent biomarker parameters of asphaltites. ......................319

Table 8.4 Maturity-dependent molecular parameters of asphaltites. ...................322

xxiii

Table 8.5 Key geochemical parameters used in oil-oil and oil-source rock correlations for the southern Australian coastal asphaltite. ..................332

Table 8.6 Yield and composition of marine sediment extracts and a marine oil. ........................................................................................................335

Table 8.7 Alkane parameters and isotopic composition of marine sediment extracts and a marine oil. .....................................................................335

Table 8.8 Source-dependent biomarker parameters of marine sediment extracts and a marine oil. ...................................................................................336

Table 8.9 Maturity-dependent biomarker parameters of marine sediment extracts and a marine oils. .................................................................................336

Table 9.1 Bulk composition of beached oil slicks and other petroleum substances. ............................................................................................349

Table 9.2 Alkane parameters of beached oil slicks and other petroleum substances. ............................................................................................351

Table 9.3 Source-dependent biomarker parameters of beached oil slicks and tanker oils. ............................................................................................355

Table 9.4 Highly source-specifi c biomarker parameters of beached oil slicks and tanker oils. .....................................................................................356

Table 9.5 Maturity-dependent molecular parameters of oil slicks and tanker oils. .......................................................................................................360

Table A1.2.1 Key to analytical procedures. ...............................................................439

Table A1.2.2 Sediment samples, onshore western Otway Basin. ..............................439

Table A1.2.3 Sediment samples, offshore western Otway Basin. .............................440

Table A1.2.4 Oil samples, Otway Basin ...................................................................442

Table A1.2.5 Reservoir bitumen samples, western Otway Basin ..............................442

Table A1.2.6 Sediment samples from the Ceduna Sub-basin collected during the RV Rig Seismic, Cruise 102.RV Rig Seismic, Cruise 102.RV ..........................................................443

Table A1.2.7 Miscellaneous oil samples from ships and Port Stanvac Refi nery. ......443

Table A1.2.8 Non-Australian samples of oil, sediment and coastal bitumen. ...........444

Table A1.2.9 Coastal amber and reference samples of resin and resinite. .................445

Table A1.2.10 Coastal pumice and reference samples of pumice. ............................445

Table A2.3.1 External carbon isotope standards. .......................................................455

Table A2.3.2 International correlation of carbon isotope values for the hydrocarbon fractions of coastal bitumen samples. ..................................................455

Table A3.1.1 Historical occurrences of stranded coastal bitumen along the Australian coast line. ............................................................................460

xxiv

Table A3.1.2 Historical occurrences of stranded coastal amber along the Australian coast line. ............................................................................464

Table A3.1.3 Historical occurrences of algal blooms in South Australian coastal waters. ......................................................................................464

Table A3.2.1 Key to abbreviations used in Appendix A3.2. ......................................465

Table A3.2.2 Miscellaneous samples of coastal bitumen and wax assembled from museums and private collections. ........................................................466

Table A3.2.3 Samples of coastal bitumen collected in South Australia from the South Australian Department of Mines and Energy coastal bitumen survey, 1983. ........................................................................................469

Table A3.2.4 Samples of coastal bitumen collected in Victoria from the coastal bitumen survey, 1990-1991. .................................................................471

Table A3.2.5 Samples of coastal bitumen collected in southeast South Australia from the coastal bitumen survey, 1990-1991. ......................................473

Table A2.3.6 Samples of coastal ambers assembled from museums and collected in the coastal bitumen survey, 1990-1991. ...........................................485

Table 4.2.1 Rock-Eval Pyrolysis Data of the Potoroo Formation ...........................502

Table 5.5.1 Summary of Vitrinite Refl ectance Measurements, Chama-1A. ...........571

Table 5.5.2 Summary of Vitrinite Refl ectance Measurements, Mocamboro-11. ....581

Table A6.1.1 Bulk composition of Austalian coastal bitumens which have been compiled from reports and papers. .......................................................590

Table A6.1.2 Alkane parameters and isotopic compositions of coastal bitumens which have been compiled from reports and papers. ...........................593

Table A6.1.3 Source-specifi c biomarker parameters of coastal bitumens which have been compiled from reports and papers. ......................................596

Table A6.1.4 Maturity-dependent biomarker parameters of coastal bitumens which have been compiled from reports and papers. ...........................597

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List of Plates

Plate 4.1 .......................................................................................................................... 94

Plate 4.2 .......................................................................................................................... 96

Plate 4.3 .......................................................................................................................... 98

Plate 4.4 ........................................................................................................................ 103

Plate 4.5 ........................................................................................................................ 106

Plate 4.6 ........................................................................................................................ 114

Plate 5.1 ........................................................................................................................ 144

Plate 5.2 ........................................................................................................................ 150

Plate 6.1 ........................................................................................................................ 206

xxvi