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Trumpet-1

Geochemical data indicate the majority of samples in Trumpet-1, between 1070 and 2252 mKB, have low source richness, with TOC <1%. Good source richness,capable of supporting effective source rocks, with TOC >2% is only apparent at 1268 mKB. Source quality is generally poor with gas-prone Type III/IV organicmatter (HI <100 mg HC/g TOC). An exception (HI of 367 mg HC/g TOC) occurs at 1326 mKB, however, low TOC and S2 yields indicate this value is unreliable.Maturity is insufficient for hydrocarbon generation above 2090 mKB (VR <0.65%). Nonetheless, high Tmax values (>440oC) present at shallower depths support ahigher maturity. However, the wide scatter in Tmax values suggests a high level of unreliability due to a combination of low S2 yields and oxidation of organicmaterial during deposition. The accompanying high PI values (PI >0.15, with some >0.4) indicate free hydrocarbons throughout the succession. It is uncertain if thebase of the well has reached maturities sufficient for oil generation due to the ‘noise’ in the Rock Eval data. Tmax data shows less variability suggesting thatappropriately high maturities have been attained.

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Depth plot (from left to right) of total organic carbon (TOC; Wt%), Rock Eval S2 (mg HC/g TOC), Rock Eval Hydrogen Index(HI; mg HC/g TOC), Rock Eval Production Index (PI), Rock Eval Tmax (oC), and vitrinite reflectance (%) in Trumpet-1.

Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Plot of Rock Eval Hydrogen Index (HI; mg HC/g TOC) versus (from left to right) Rock Eval Oxygen Index (OI; mg CO2/g TOC), Tmax (oC), and total organic carbon(TOC; Wt%) in Trumpet-1. Note: Modified van Krevelen diagrams show maturation pathways of kerogens.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Source richness plot of Rock Eval S1+S2 (mg HC/g rock) versus total organic carbon (TOC; Wt%), and source maturity plot of Rock Eval Tmax (oC) versus RockEval Production Index (PI) in Trumpet-1.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Crayfish-A1

Geochemical data indicate good source richness, capable of supporting effective source rocks, with TOC >2%, is consistently found below 2300 mRT. In addition,good source quality with oil prone, Type I, II and II/III organic matter (HI >300 mg HC/g TOC), is found predominantly below 2200 mRT. Gas prone, Type III organicmatter (HI <200 mg HC/g TOC), occurs between 540 mRT to TD. Maturity is sufficient for hydrocarbon generation below 2300 mRT (VR >0.65%, Rock Eval Tmax>440°C). The onset of oil expulsion from mature source rocks is likely to occur below 2650 mRT (>0.75% VR). A VR of 1.2% at TD indicates these sediments havematurities at boundary between the oil and gas windows. This maturity assessment is further supported by concentrated elevated production indices (PI >0.15) nearTD. At shallower depths, elevated PIs (some >0.4) and low Tmax signifies oil staining with oil expulsion and migration from the deeper mature source rocks in thewell to shallower sandier intervals.

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Depth plot (from left to right) of total organic carbon (TOC; Wt%), Rock Eval S2 (mg HC/g TOC), Rock Eval Hydrogen Index(HI; mg HC/g TOC), Rock Eval Production Index (PI), Rock Eval Tmax (oC), and vitrinite reflectance (%) in Crayfish-A1.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Plot of Rock Eval Hydrogen Index (HI; mg HC/g TOC) versus (from left to right) Rock Eval Oxygen Index (OI; mg CO2/g TOC), Tmax (oC), and total organic carbon(TOC; Wt%) in Crayfish-A1. Note: Modified van Krevelen diagrams show maturation pathways of kerogens.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Source richness plot of Rock Eval S1+S2 (mg HC/g rock) versus total organic carbon (TOC; Wt%), and source maturity plot of Rock Eval Tmax (oC) versus RockEval Production Index (PI) in Crayfish-A1.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Neptune-1

Geochemical data indicate the majority of samples in Neptune-1 have very low source richness, with TOC <0.5%. Good source richness, capable of supportingeffective source rocks, with TOC >2%, is isolated to the sample at 2249 mKB. Source quality is moderate for samples at 1120 and 2249 mKB with Type III organicmatter having minor liquids potential (HI = 207 mg HC/g TOC). However, it is only in the deeper sample that the source richness is adequate. This is also the casefor the Type II organic matter at 1378 mKB where poor source richness (TOC = 0.5%) would limit its potential. The rest of the section has only minor gas to nohydrocarbon potential in Type III to Type IV organic matter. VR indicates sufficient maturity for hydrocarbon generation at 2249 mKB. Rock Eval Tmaxmeasurements >440°C indicate maturity over a larger section from 700 mKB to TD, but is considered to be unreliable due to the generally low S2 yields (<0.5 mgHC/g rock). The high PI (>0.15 with some >0.4) over most of the succession is consistent with the shows and most likely indicates migration through the section.

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Depth plot (from left to right) of total organic carbon (TOC; Wt%), Rock Eval S2 (mg HC/g TOC), Rock Eval Hydrogen Index(HI; mg HC/g TOC), Rock Eval Production Index (PI), Rock Eval Tmax (oC), and vitrinite reflectance (%) in Neptune-1.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Plot of Rock Eval Hydrogen Index (HI; mg HC/g TOC) versus (from left to right) Rock Eval Oxygen Index (OI; mg CO2/g TOC), Tmax (oC), and total organic carbon(TOC; Wt%) in Neptune-1. Note: Modified van Krevelen diagrams show maturation pathways of kerogens.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Source richness plot of Rock Eval S1+S2 (mg HC/g rock) versus total organic carbon (TOC; Wt%), and source maturity plot of Rock Eval Tmax (oC) versus RockEval Production Index (PI) in Neptune-1.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Troas-1

There is insufficient data to accurately assess the hydrocarbon potential at Troas-1. Data indicates that source richness and maturity is insufficient for hydrocarbongeneration and expulsion with all values having TOC <2% and VR <0.65%.

Troas-1/ST1

The majority of the samples analysed in Troas-1ST, have low source richness with TOC <1%. Good source richness, capable of supporting effective source rocks(TOC >2%) occurs in samples at 1568, 2049 and 2569 mRT. Excellent source richness (TOC >40%) is identified in the coal at 2286 mRT. Good oil prone, Type II/IIIorganic matter (HI >300 mg HC/g TOC) occurs from 2050 to 2350 mRT. There is also residual gas potential (HI <150 mg HC/g TOC) between 2500 and 3500 mRT.The onset of oil generation occurs at 2100 mRT with VR and Tmax approximately 0.65% and 440oC, respectively. Expulsion begins at 2250 mRT where VR =0.75% and Tmax is at 445oC. The end of the oil window and beginning of the gas window is at 3000 mRT where Tmax ≈ 465oC and VR ≈ 1.2%. High PI values (PI>0.15) towards the base of the well support local generation and expulsion of hydrocarbons from mature to overmature source rocks.

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Depth plot (from left to right) of total organic carbon (TOC; Wt%), Rock Eval S2 (mg HC/g TOC), Rock Eval Hydrogen Index(HI; mg HC/g TOC), Rock Eval Production Index (PI), Rock Eval Tmax (oC), and vitrinite reflectance (%) in Troas-1.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Depth plot (from left to right) of total organic carbon (TOC; Wt%), Rock Eval S2 (mg HC/g TOC), Rock Eval Hydrogen Index(HI; mg HC/g TOC), Rock Eval Production Index (PI), Rock Eval Tmax (oC), and vitrinite reflectance (%) in Troas-1/ST1.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Plot of Rock Eval Hydrogen Index (HI; mg HC/g TOC) versus (from left to right) Rock Eval Oxygen Index (OI; mg CO2/g TOC), Tmax (oC), and total organic carbon(TOC; Wt%) in Troas-1/ST1. Note: Modified van Krevelen diagrams show maturation pathways of kerogens.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Source richness plot of Rock Eval S1+S2 (mg HC/g rock) versus total organic carbon (TOC; Wt%), and source maturity plot of Rock Eval Tmax (oC) versus RockEval Production Index (PI) in Troas-1/ST1.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Morum-1

Although geochemical data are sparse in Morum-1, they indicate poor source richness; only two samples have TOCs >1% (2134 and 2390 mKB). Unfortunately, thisinterval contains only Type III to Type IV organic matter (HI <100 mg HC/g TOC) and shows limited gas potential. VR values vary below 1800 mKB betweenanalysts, with two main maturity ‘trends’. Maturity VR values range from 0.67% at 2304 mKB (AMDEL) and 0.28% at 2435 mKB (Padley). The Tmax ofapproximately 440°C at 2408 mKB is more consistent with the higher maturity profile (AMDEL). Therefore, maturity sufficient for oil generation is likely to be attainedbelow 2300 mKB (VR >0.65%). The high PI (>0.15 with some >0.4) below 2125 mKB is more likely to signify oil migration through the section than expulsion from alocal mature source rock.

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Depth plot (from left to right) of total organic carbon (TOC; Wt%), Rock Eval S2 (mg HC/g TOC), Rock Eval Hydrogen Index(HI; mg HC/g TOC), Rock Eval Production Index (PI), Rock Eval Tmax (oC), and vitrinite reflectance (%) in Morum-1.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Plot of Rock Eval Hydrogen Index (HI; mg HC/g TOC) versus (from left to right) Rock Eval Oxygen Index (OI; mg CO2/g TOC), Tmax (oC), and total organic carbon(TOC; Wt%) in Morum-1. Note: Modified van Krevelen diagrams show maturation pathways of kerogens.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Source richness plot of Rock Eval S1+S2 (mg HC/g rock) versus total organic carbon (TOC; Wt%), and source maturity plot of Rock Eval Tmax (oC) versus RockEval Production Index (PI) in Morum-1.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Copa-1

Geochemical assessments are based on a limited number of analyses in Copa-1. Good source richness, capable of supporting effective source rocks, with TOC>2% is only found at 3195 mKB. No oil prone organic matter (HI >300 mg HC/g TOC) occurs in the succession. Source quality indicates that the Type III to IVorganic matter is gas prone (HI <150 mg HC/g TOC). Unfortunately, there is not sufficient maturity for hydrocarbon generation with Rock Eval Tmax <440°C. Theelevated PI (>0.15 with some >0.4) over most of the succession is more likely to signify oil migration through the section than a mature source rock.

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Depth plot (from left to right) of total organic carbon (TOC; Wt%), Rock Eval S2 (mg HC/g TOC), Rock Eval Hydrogen Index(HI; mg HC/g TOC), Rock Eval Production Index (PI), Rock Eval Tmax (oC), and vitrinite reflectance (%) in Copa-1.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Plot of Rock Eval Hydrogen Index (HI; mg HC/g TOC) versus (from left to right) Rock Eval Oxygen Index (OI; mg CO2/g TOC), Tmax (oC), and total organic carbon(TOC; Wt%) in Copa-1. Note: Modified van Krevelen diagrams show maturation pathways of kerogens.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Source richness plot of Rock Eval S1+S2 (mg HC/g rock) versus total organic carbon (TOC; Wt%), and source maturity plot of Rock Eval Tmax (oC) versus RockEval Production Index (PI) in Copa-1.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Argonaut-A1

In Argonaut-A1, good source richness, capable of supporting effective source rocks, with TOC >2% is found in isolated samples between 500 and 3125 mKB.Unfortunately, this interval does not have good source quality since no samples show oil prone organic matter with HI >300 mg HC/g TOC. The samples indicateonly gas prone Type III organic matter, with the majority of samples having HI <150 mg HC/g TOC. VR data show a wide variation between analysts below 2500mKB, with two main maturity ‘trends’. Maturity VR values at TD range from 0.7% (Robertson Research) to 1.0% (AMDEL). The Tmax of ~445°C at TD is moreconsistent with the lower maturity profile (Robertson Research), as is the limited VR analyses from Cook Services. Therefore, maturities sufficient for oil generationare likely to be attained below 3200 mKB (VR >0.65%). The high PI (>0.15 with some >0.4) over most of the succession is more likely to signify oil migration throughthe section rather than a mature source rock.

Depth plot (from left to right) of total organic carbon (TOC; Wt%), Rock Eval S2 (mg HC/g TOC), Rock Eval Hydrogen Index(HI; mg HC/g TOC), Rock Eval Production Index (PI), Rock Eval Tmax (oC), and vitrinite reflectance (%) in Argonaut-A1.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Plot of Rock Eval Hydrogen Index (HI; mg HC/g TOC) versus (from left to right) Rock Eval Oxygen Index (OI; mg CO2/g TOC), Tmax (oC), and total organic carbon(TOC; Wt%) in Argonaut-A1. Note: Modified van Krevelen diagrams show maturation pathways of kerogens.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Plot of Rock Eval Hydrogen Index (HI; mg HC/g TOC) versus (from left to right) Rock Eval Oxygen Index (OI; mg CO2/g TOC), Tmax (oC), and total organic carbon(TOC; Wt%) in Argonaut-A1. Note: Modified van Krevelen diagrams show maturation pathways of kerogens.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

Source richness plot of Rock Eval S1+S2 (mg HC/g rock) versus total organic carbon (TOC; Wt%), and source maturity plot of Rock Eval Tmax (oC) versus RockEval Production Index (PI) in Argonaut-A1.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Breaksea Reef-1

In Breaksea Reef-1, good source richness, capable of supporting effective source rocks, with TOC >2% is consistently found from 900 to 4250 mKB. Unfortunately,this interval does not have good source quality as no samples have oil prone organic matter (HI >300 mg HC/g TOC). The samples indicate mainly gas potential withminor liquids from Type III organic matter (HI <200 mg HC/g TOC). The sediments below 3300 mKB are mature for hydrocarbon generation with VR >0.65% andTmax >440°C. This is further supported by the elevated production indices (PI >0.15) below 3200 mKB.

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Depth plot (from left to right) of total organic carbon (TOC; Wt%), Rock Eval S2 (mg HC/g TOC), Hydrogen Index (HI; mgHC/g TOC), Rock Eval Production Index (PI), Rock Eval Tmax (oC), and vitrinite reflectance (%) in Breaksea Reef-1.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Plot of Rock Eval Hydrogen Index (HI; mg HC/g TOC) versus (from left to right) Rock Eval Oxygen Index (OI; mg CO2/g TOC), Tmax (oC), and total organic carbon(TOC; Wt%) in Breaksea Reef-1. Note: Modified van Krevelen diagrams show maturation pathways of kerogens.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Source richness plot of Rock Eval S1+S2 (mg HC/g rock) versus total organic carbon (TOC; Wt%), and source maturity plot of Rock Eval Tmax (oC) versus RockEval Production Index (PI) in Breaksea Reef-1.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Discovery Bay-1

In Discovery Bay-1, samples with good source richness, capable of supporting effective source rocks, with TOC >2% are sparse below 950 mKB. Unfortunately, thisinterval does not have good source quality since no samples show oil prone organic matter with HI >300 mg HC/g TOC. The source material is gas prone, with HI<100mg HC/g TOC, in samples below 800 mKB. VR indicates maturity sufficient for hydrocarbon generation (VR >0.65%) below 2500 mKB. However, the low Tmax(<440oC) is inconsistent with the majority of the VR data (Unreported analyst) and is more consistent with the limited VR data with lower values from GeotechnicalServices. The low PI values are consistent with a marginally mature sequence at TD.

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Depth plot (from left to right) of total organic carbon (TOC; Wt%), Rock Eval S2 (mg HC/g TOC), Rock Eval Hydrogen Index(HI; mg HC/g TOC), Rock Eval Production Index (PI), Rock Eval Tmax (oC), and vitrinite reflectance (%) in Discovery Bay-1.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Plot of Rock Eval Hydrogen Index (HI; mg HC/g TOC) versus (from left to right) Rock Eval Oxygen Index (OI; mg CO2/g TOC), Tmax (oC), and total organic carbon(TOC; Wt%) in Discovery Bay-1. Note: Modified van Krevelen diagrams show maturation pathways of kerogens.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Source richness plot of Rock Eval S1+S2 (mg HC/g rock) versus total organic carbon (TOC; Wt%), and source maturity plot of Rock Eval Tmax (oC) versus RockEval Production Index (PI) in Discovery Bay-1.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Voluta-1

Geochemical data indicate source richness capable of supporting effective source rocks, with TOC >2% is only observed in isolated samples at 1917, 2168 and2897 mDF, even though the succession has been extensively sampled below 2300 mDF. The disappointing source richness is matched by very poor source quality,with only very minor gas potential from Type III/IV to Type IV organic matter (HI <100 mg HC/g TOC). Samples with higher HI occur within the deeper succession.VR data are highly variable depending on the analyst involved. However, using the combined datasets of AMDEL and Cook Services, the VR profile is consistentwith the majority of the Tmax data. The onset of oil generation is taken at 3000 mDF where VR ~0.65% and Tmax is consistently around 440oC. The onset ofexpulsion is at 3500 mDF where VR and Tmax values of 0.75% and 445oC are reported. High PI values (>0.15) indicate oil migration through the successionresulting from a combination of local generation and migration.

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Depth plot (from left to right) of total organic carbon (TOC; Wt%), Rock Eval S2 (mg HC/g TOC), Rock Eval Hydrogen Index(HI; mg HC/g TOC), Rock Eval Production Index (PI), Rock Eval Tmax (oC), and vitrinite reflectance (%) in Voluta-1.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Plot of Rock Eval Hydrogen Index (HI; mg HC/g TOC) versus (from left to right) Rock Eval Oxygen Index (OI; mg CO2/g TOC), Tmax (oC), and total organic carbon(TOC; Wt%) in Voluta-1. Note: Modified van Krevelen diagrams show maturation pathways of kerogens.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Source richness plot of Rock Eval S1+S2 (mg HC/g rock) versus total organic carbon (TOC; Wt%), and source maturity plot of Rock Eval Tmax (oC) versus RockEval Production Index (PI) in Voluta-1.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Bridgewater Bay-1

Geochemical data indicate good source richness, capable of supporting effective source rocks, with TOC >2% is consistently found below 725 mKB, with excellentsource potential (TOC >10%) occurring below 3750 mKB. The source quality of the samples indicates both oil and gas potential from Type II and III organic matter.There is good source quality with oil prone organic matter (HI >300 mg HC/g TOC) below 3625 mKB. Gas potential is indicated from 725 mKB to TD (HI <200 mgHC/g TOC). Sufficient maturity for hydrocarbon generation is achieved below 2500 mKB with VR >0.65% and Tmax >440°C. Oil expulsion from mature source rocksis likely to occur below 3300 mKB (VR >0.75%), with onset of oil to gas cracking and the beginning of the gas window below 4100 mKB (VR >1.2%). High PI values(>0.15) are consistent with oil generation whereas PI >0.4 (with low Tmax) between 2980 and 3980 mKB suggests oil staining. This suggests oil migration throughthe section.

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Depth plot (from left to right) of total organic carbon (TOC; Wt%), Rock Eval S2 (mg HC/g TOC), Hydrogen Index (HI; mgHC/g TOC), Rock Eval Production Index (PI), Rock Eval Tmax (oC), and vitrinite reflectance (%) in Bridgewater Bay-1.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Plot of Rock Eval Hydrogen Index (HI; mg HC/g TOC) versus (from left to right) Rock Eval Oxygen Index (OI; mg CO2/g TOC), Tmax (oC), and total organic carbon(TOC; Wt%) in Bridgewater Bay-1. Note: Modified van Krevelen diagrams show maturation pathways of kerogens.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Source richness plot of Rock Eval S1+S2 (mg HC/g rock) versus total organic carbon (TOC; Wt%), and source maturity plot of Rock Eval Tmax (oC) versus RockEval Production Index (PI) in Bridgewater Bay-1.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Minerva-1

The available data for this well is sparse. Only one sample (1837 mRT) shows good source richness, capable of supporting effective source rocks, with TOC >2%.This coal sample contains oil prone Type II/III organic matter with a HI of 450 mg HC/g TOC. The remaining samples show only gas potential from Type III organicmatter. Sufficient maturity for hydrocarbon generation occurs below 2300 mRT (VR >0.65%) towards the base of the well. PI values of <0.1 further supports theimmaturity of the section above 1900 mRT; the deepest sample for Rock Eval.

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Depth plot (from left to right) of total organic carbon (TOC; Wt%), Rock Eval S2 (mg HC/g TOC), Rock Eval Hydrogen Index(HI; mg HC/g TOC), Rock Eval Production Index (PI), Rock Eval Tmax (oC), and vitrinite reflectance (%) in Minerva-1.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Plot of Rock Eval Hydrogen Index (HI; mg HC/g TOC) versus (from left to right) Rock Eval Oxygen Index (OI; mg CO2/g TOC), Tmax (oC), and total organic carbon(TOC; Wt%) in Minerva-1. Note: Modified van Krevelen diagrams show maturation pathways of kerogens.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Source richness plot of Rock Eval S1+S2 (mg HC/g rock) versus total organic carbon (TOC; Wt%), and source maturity plot of Rock Eval Tmax (oC) versus RockEval Production Index (PI) in Minerva-1.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Conan-1

No source rock data is available for this well. However, based on the limited VR data, maturities are insufficient for oil generation with VR estimated to be <0.65% atTD.

Depth plot (from left to right) of total organic carbon (TOC; Wt%), Rock Eval S2 (mg HC/g TOC), Rock Eval Hydrogen Index(HI; mg HC/g TOC), Rock Eval Production Index (PI), Rock Eval Tmax (oC), and vitrinite reflectance (%) in Conan-1.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Mussel-1

The available data for Mussel-1 is sparse but indicates good source richness, capable of supporting effective source rocks, with TOC >2% between 2100 and 2240mRT. However, source quality is poor with mainly gas prone Type III organic matter (HI <150 mg HC/g TOC). The VR profile indicates insufficient maturity forhydrocarbon generation with the organic matter remaining immature (VR <0.65%, Tmax <440oC) at TD. The high PI (>0.15) signifies hydrocarbon migration throughthe section as opposed to generation and expulsion from a mature source.

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Depth plot (from left to right) of total organic carbon (TOC; Wt%), Rock Eval S2 (mg HC/g TOC), Rock Eval Hydrogen Index(HI; mg HC/g TOC), Rock Eval Production Index (PI), Rock Eval Tmax (oC), and vitrinite reflectance (%) in Mussel-1.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Plot of Rock Eval Hydrogen Index (HI; mg HC/g TOC) versus (from left to right) Rock Eval Oxygen Index (OI; mg CO2/g TOC), Tmax (oC), and total organic carbon(TOC; Wt%) in Mussel-1. Note: Modified van Krevelen diagrams show maturation pathways of kerogens.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Source richness plot of Rock Eval S1+S2 (mg HC/g rock) versus total organic carbon (TOC; Wt%), and source maturity plot of Rock Eval Tmax (oC) versus RockEval Production Index (PI) in Mussel-1.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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La Bella-1

The available data for La Bella-1 is sparse, but indicates good source richness capable of supporting effective source rocks, with TOC >2% between 1430 and 2600mRT. Unfortunately, source quality is generally poor for oil. Gas and minor liquid prone Type III organic matter (HI <200 mg HC/g TOC) is found between 1430 and2600 mRT, whereas only one sample shows increased liquid potential (HI = 254 mg HC/g TOC) from Type II/III organic matter at 2541 mRT. VR and Tmax profilesindicate sufficient maturity (VR >0.65%, Tmax >440°C) for hydrocarbon generation below 2450 mRT. The relatively low PI of <0.15 in the deeper early maturesuccession is not a true reflection of the maturity but is responding to the very limited liquid potential of the disseminated organic matter. The higher PI values in theshallower samples indicate staining, and are most likely the result of migration rather than hydrocarbon generation and expulsion.

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Depth plot (from left to right) of total organic carbon (TOC; Wt%), Rock Eval S2 (mg HC/g TOC), Rock Eval Hydrogen Index(HI; mg HC/g TOC), Rock Eval Production Index (PI), Rock Eval Tmax (oC), and vitrinite reflectance (%) in La Bella-1.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Plot of Rock Eval Hydrogen Index (HI; mg HC/g TOC) versus (from left to right) Rock Eval Oxygen Index (OI; mg CO2/g TOC), Tmax (oC), and total organic carbon(TOC; Wt%) in La Bella-1. Note: Modified van Krevelen diagrams show maturation pathways of kerogens.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Source richness plot of Rock Eval S1+S2 (mg HC/g rock) versus total organic carbon (TOC; Wt%), and source maturity plot of Rock Eval Tmax (oC) versus RockEval Production Index (PI) in La Bella-1.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Nautilus-A1

Although geochemical data are sparse, they suggest good source richness, capable of supporting effective source rocks, with TOC >2% below ~1730 mKB.However, source quality is extremely poor for oil in the one sample analysed near TD. This sample contains gas prone, Type IV organic matter. VR data indicateinsufficient maturity for hydrocarbon expulsion (<0.65%). The low PI (<0.15) at 1966 mKB is consistent with the immaturity of the section.

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Depth plot (from left to right) of total organic carbon (TOC; Wt%), Rock Eval S2 (mg HC/g TOC), Rock Eval Hydrogen Index(HI; mg HC/g TOC), Rock Eval Production Index (PI), Rock Eval Tmax (oC), and vitrinite reflectance (%) in Nautilus-A1.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Plot of Rock Eval Hydrogen Index (HI; mg HC/g TOC) versus (from left to right) Rock Eval Oxygen Index (OI; mg CO2/g TOC), Tmax (oC), and total organic carbon(TOC; Wt%) in Nautilus-A1. Note: Modified van Krevelen diagrams show maturation pathways of kerogens.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Source richness plot of Rock Eval S1+S2 (mg HC/g rock) versus total organic carbon (TOC; Wt%), and source maturity plot of Rock Eval Tmax (oC) versus RockEval Production Index (PI) in Nautilus-A1.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Triton-1

The data for this well is sparse. There is insufficient source richness to support an effective source for liquid hydrocarbons, with no sample having >2% TOC. Sourcequality is poor with minor gas potential from Type III/IV organic matter (HI <100 mg HC/g TOC). VR and Tmax data indicate immaturity for hydrocarbon generationwith VR <0.65% and Tmax <440oC. One exception occurs at 2830 mKB, where sediment is marginally mature close to the onset of oil generation. The high Tmaxvalue at this depth is unreliable due to the very low S2 yield. High PI values at >0.15 indicate migration of liquid hydrocarbons through the section.

Triton-1/ST1There is insufficient source richness to support an effective source rock for liquid hydrocarbons with no sample having >2% TOC. There is no Rock Eval data for thesidetrack of this well. Combined VR data from Triton-1/ST1 and Triton-1, indicates that the onset of oil generation at VR = 0.65% occurs at ~2900 mKB, whereas theonset of expulsion at VR = 0.75% occurs at ~3100 mKB if source quality is sufficiently good. The progressive decrease in TOC with depth towards the base of thewell is consistent with the loss of organic matter through oil generation.

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Depth plot (from left to right) of total organic carbon (TOC; Wt%), Rock Eval S2 (mg HC/g TOC), Rock Eval Hydrogen Index(HI; mg HC/g TOC), Rock Eval Production Index (PI), Rock Eval Tmax (oC), and vitrinite reflectance (%) in Triton-1.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Plot of Rock Eval Hydrogen Index (HI; mg HC/g TOC) versus (from left to right) Rock Eval Oxygen Index (OI; mg CO2/g TOC), Tmax (oC), and total organic carbon(TOC; Wt%) in Triton-1. Note: Modified van Krevelen diagrams show maturation pathways of kerogens.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Source richness plot of Rock Eval S1+S2 (mg HC/g rock) versus total organic carbon (TOC; Wt%), and source maturity plot of Rock Eval Tmax (oC) versus RockEval Production Index (PI) in Triton-1.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Depth plot (from left to right) of total organic carbon (TOC; Wt%), Rock Eval S2 (mg HC/g TOC), Rock Eval Hydrogen Index(HI; mg HC/g TOC), Rock Eval Production Index (PI), Rock Eval Tmax (oC), and vitrinite reflectance (%) in Triton-1/ST1.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Eric the Red-1

This well is difficult to interpret due to sparse data. The available data suggest good source richness, capable of supporting effective source rocks, with TOC >2% inisolated samples below approximately 500 mRT. Source quality is poor being mainly gas prone Type III organic matter (HI <200 mg HC/g TOC) from 500 to 1625mRT. The isolated coal at 1275 mRT shows limited liquids potential with an HI of 224 mg HC/g TOC. VR data indicates that the succession is immature to 1630mRT, and is only marginally mature close to TD at 1830 mRT. The low PI values (predominantly <0.1) support the lack of maturity.

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Depth plot (from left to right) of total organic carbon (TOC; Wt%), Rock Eval S2 (mg HC/g TOC), Rock Eval Hydrogen Index(HI; mg HC/g TOC), Rock Eval Production Index (PI), Rock Eval Tmax (oC), and vitrinite reflectance (%) in Eric the Red-1.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003

Plot of Rock Eval Hydrogen Index (HI; mg HC/g TOC) versus (from left to right) Rock Eval Oxygen Index (OI; mg CO2/g TOC), Tmax (oC), and total organic carbon(TOC; Wt%) in Eric the Red-1. Note: Modified van Krevelen diagrams show maturation pathways of kerogens.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Source richness plot of Rock Eval S1+S2 (mg HC/g rock) versus total organic carbon (TOC; Wt%), and source maturity plot of Rock Eval Tmax (oC) versus RockEval Production Index (PI) in Eric the Red-1.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Loch Ard-1

No Rock Eval data is available for this well. Maturity is insufficient for hydrocarbon generation with VR <0.65% to TD.

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Depth plot (from left to right) of total organic carbon (TOC; Wt%), Rock Eval S2 (mg HC/g TOC), Rock Eval Hydrogen Index(HI; mg HC/g TOC), Rock Eval Production Index (PI), Rock Eval Tmax (oC), and vitrinite reflectance (%) in Loch Ard-1.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Snail-1

Geochemical data indicate good source richness (TOC >2%) capable of supporting effective source rocks is found from 750 to 820 mKB and at 963 mKB, whereasthe majority of samples between 244 and 1232 mKB have TOC <1%. Overall, the source quality for this section is poor with minor gas prone Type III organic matter(HI <100 mg HC/g TOC). VR and Tmax data indicate that the succession is immature to TD (VR <0.65% and Tmax <440oC). The high PI (>0.15) around 800 mKBwithin the organic-rich samples may indicate free hydrocarbons within the interbedded coarser-grained sediments. Early oil generation is not likely to have occurredfrom this narrow interval considering the poor source quality of the organic matter.

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Depth plot (from left to right) of total organic carbon (TOC; Wt%), Rock Eval S2 (mg HC/g TOC), Rock Eval Hydrogen Index(HI; mg HC/g TOC), Rock Eval Production Index (PI), Rock Eval Tmax (oC), and vitrinite reflectance (%) in Snail-1.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Plot of Rock Eval Hydrogen Index (HI; mg HC/g TOC) versus (from left to right) Rock Eval Oxygen Index (OI; mg CO2/g TOC), Tmax (oC), and total organic carbon(TOC; Wt%) in Snail-1. Note: Modified van Krevelen diagrams show maturation pathways of kerogens.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Source richness plot of Rock Eval S1+S2 (mg HC/g rock) versus total organic carbon (TOC; Wt%), and source maturity plot of Rock Eval Tmax (oC) versus RockEval Production Index (PI) in Snail-1.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Nerita-1

Good source richness (TOC >2%) capable of supporting effective source rocks is consistently found between 540 and 1500 mDF, with coals (TOC >40%) observedbetween 770 and 1190 mDF. Source quality is good with coals containing oil prone Type II/III organic matter (HI >300 mg HC/g TOC). The remaining organic-richrocks are predominately gas prone and contain Type III organic matter (HI <200mg HC/g TOC). Unfortunately, VR and Tmax data indicate that there is insufficientmaturity for hydrocarbon generation (VR <0.65% and Tmax <440°C at TD of 2042 mDF). PI values reinforce the immaturity of the section with values predominantly<0.1.

Depth plot (from left to right) of total organic carbon (TOC; Wt%), Rock Eval S2 (mg HC/g TOC), Rock Eval Hydrogen Index(HI; mg HC/g TOC), Rock Eval Production Index (PI), Rock Eval Tmax (oC), and vitrinite reflectance (%) in Nerita-1.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Plot of Rock Eval Hydrogen Index (HI; mg HC/g TOC) versus (from left to right) Rock Eval Oxygen Index (OI; mg CO2/g TOC), Tmax (oC), and total organic carbon(TOC; Wt%) in Nerita-1. Note: Modified van Krevelen diagrams show maturation pathways of kerogens.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.

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Source richness plot of Rock Eval S1+S2 (mg HC/g rock) versus total organic carbon (TOC; Wt%), and source maturity plot of Rock Eval Tmax (oC) versus RockEval Production Index (PI) in Nerita-1.Source: www.ga.gov.au/oracle/apcrc. Accessed: April, 2003.