Cretaceous and Jurassic Source Rocks: East Texas Salt Basin, Deepwater Gulf of Mexico, Onshore Mexico. Daniel M Jarvie

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1 1 Cretaceous and Jurassic Source Rocks: East Texas Salt Basin, Deepwater Gulf of Mexico, Onshore Mexico 28 th International Meeting on Organic Geochemistry, Sep 2017, Florence, Italy Daniel M Jarvie TCU Energy Institute Worldwide Geochemistry 2017 Daniel M Jarvie. All rights reserved. Acknowledgements Joe Kast, Vaughn Resources Mike Moldowan, Biomarker Technologies Jeremy Dahl, Stanford Mike Price, Hess Craig Steinke, Renaissance Oil Geomark Research for access to RFDbase JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 2

2 2 Introduction: Area of Interest Southern North America Map modified from GeoExPro, 2015 JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 3 Late Jurassic to Early Cretaceous Paleogeography Source: Colorado Plateau GeoSystems Inc. JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 4

3 3 Early Cretaceous Lithofacies: carbonates (blue) dominate Gulf Coast with siliciclastics (yellow) in upper East Texas Source: Colorado Plateau GeoSystems Inc. JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 5 List of Source Rocks JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 6

4 4 EAST TEXAS OIL FIELD Production = 5.2 B boe (830 M m 3 ) Pearson, 2012 JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 7 Salt Withdrawal Mini Basin Peel, 2012 JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 8

5 5 Comparison of TOC Values coastal plain vs salt withdrawal Present-day Average Average Deposition Age Formation TOC (wt.%) HI (mg/g) Count Production Shallow marine Turonian Tuscaloosa Oil Marine, E. TX Turonian Eagle Ford * 84 Oil Marine, S. TX Turonian Eagle Ford * 24 Oil/gas Shallow marine M. Cretaceous Kiamichi/Goodland na Salt Basin M. Cretaceous Kiamichi/Goodland Oil Shallow marine L. Cretaceous Pearsall Group Gas Salt Basin L. Cretaceous Pearsall Group??? na Shallow marine Tithonian Bossier Dry gas Salt Basin Tithonian Bossier Dry gas Shallow marine Tithonian Bossier na Shallow marine Kimmeridgian Haynesville Dry gas Salt Basin Kimmeridgian Haynesville Dry gas Shallow marine Oxfordian Smackover* 0.54 na 537 Oil Shallow marine Oxfordian Smackover* (immature) ( ) 4 Oil Deepwater Oxfordian ~ Smackover * 24 (Oil) *Smackover data from Sassen and Moore, 1988 JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 9 Archived vs Fresh Cuttings, Core: Evaporation results in low S1 in archived cuttings whereas oxidation appears to cause the reduction in S2 and TOC as a result of high CO 2 in pyrolysis effluent split ca. 3x higher ca. 3x lower Jarvie, 2017a, AAPG Course Notes JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 10

6 6 East Texas Stratigraphic calls are variable Baker, 1995 Bruno et al., 1991 JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 11 Background of Glen Rose Production and Oil Geochemistry Upper Glen Rose Tight carbonate Lower Glen Rose separated from U. Glen Rose by massive anhydrite Interbedded shales: Bexar and Pine Island (Pearsall Group) Lower Glen Rose has produced oil and gas from over 360 wells in Alabama Ferry field (as of 2014) Average cumulative oil: 112,000 bbls/well Average cumulative gas: 407,000 mcf gas/well Average GOR: 3,600 scf/stb/well Postulated to be an U. Jurassic or L. Cretaceous source rock (Bruno et al., 1991) JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 12

7 7 L. Glen Rose (Pearsall) Geochemistry TOC 83% of present-day TOC values range from 0.00 to 0.50 wt.%; only 9% exceed 1.00 wt.% Only 12% of original TOC values are > 1.00 wt.% HI of restored TOC and S2 values is ca. 270 mg/g for those samples with greater than 1% TOC The restored values suggest a very modest 51,000 to 92,000 boe/acre-foot generation potential at full conversion Gas data suggests a much more mature source than Pearsall Group gases, although gas is wetter (more C 2 + gas) Pristane-to-phytane ratio is 1.5 suggesting a marine source rock (Bruno et al., 1991) There is 0.87 correlation to a Smackover source based on diamondoids (note: not all Smackover oil is marine carbonate); Smackover carbonate oils are found in other Glen Rose reservoirs particular in nne East Texas JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 13 Saturate vs Aromatic Carbon Isotopes suggest a Paleozoic source rock Cretaceous Paleozoic Data from Sofer (1984), Burgess (1990), Geomark RFDbase JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 14

8 8 Sterane Distribution shows similarity to either U. Jr. Bossier or M. Cret. Goodland and Kiamichi shales; no L. Cret. Pearsall samples available %C27 Steranes Eagle Ford/Buda Woodbine Goodland Kiamichi Bossier Glen Rose %C28 Steranes %C29 Steranes JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 15 However, Comparison of QEDA signatures from two Glen Rose oils vary from those of the Bossier and Haynesville Courtesy: Mike Moldowan, Biomarker Technologies JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 16

9 9 Deepwater GOM: select immature source rock wells in Garden Banks and Atwater Valley JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 17 Norton-754 (Garden Banks): Average present-day TOC and HI values Cenomanian Albian Barremian Tithonian Kimmeridgian Oxfordian Cenomanian Albian Barremian Tithonian Kimmeridgian Oxfordian TOC (wt.%) Average HI (mg HC/g TOC) JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 18

10 10 Organofacies and Organic Quantity Differences JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 19 Computed Total Petroleum Generation Potentials by source interval, DGOM Cenomanian 74 Albian 5 Barremian 120 Tithonian 80 Kimmeridgian 35 Oxfordian Millions Average Generation Potential (boe/section/thickness) JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 20

11 11 Diamondoids show distinct differences between Cretaceous (Turonian) Tuscaloosa condensates and U. Jr. (Oxfordian) Smackover oils Relative concentrations (Log Scale) Gulf of Mexico oil and condensate Turonian (Tuscaloosa) USA (all condensates) Oxfordian (Smackover) USA Condensate and black oil Tuscaloosa with co-source Extended diamondoids Measured Moldowan et al., 2015 JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 21 Pyrolysis high resolution gas chromatographic yields from immature DGOM source rock samples Gasier Oilier After Horsfield, 1989 JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 22

12 12 Comparison of Atwater Valley Cretaceous organofacies using bulk kinetic data 1.00 RATE OF KEROGEN CONVERSION TO HYDROCARBONS: using a constant heating rate of 3.3 o C/my 2.20 CALCULATED KEROGEN CONVERSION TEMPERATURE ( o C) 19,500-19,520 ft. 20,100-20,130 ft. Calc. %Ro CALC. VITRINITE REFLECTANCE JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 23 Comparison of Organofacies via bulk kinetic data at 3.3 o C/Ma JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 24

13 13 Compositional Kinetics by engineering P factors shows the C5 to C15+ petroleum being generated earliest at a high rate, but also a continuum of wet and dry gas generation in the oil and gas windows. Gas increases exponentially above 90% TR. JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 25 What is secondary cracking? Cracking of products formed from kerogen not just alkanes. It is a continuum of kerogen and petroleum (bitumen) cracking. The Pepper-Corvi (1995) oil cracking model fits these data the best. Jarvie, 2017b (submitted) JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 26

14 14 This is also demonstrated in SARA data where decreasing resins, increasing saturates correlate with increasing oil quality (API gravity) Data from Santamaria, 2000 JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 27 Unconventional Tight Oil System Production is best with 40 o + API and scf/stb Best Production Potential = Volatile Oil (other factors being equal) Fair Production Potential (other factors being equal) Poor Production Potential (other factors being equal) Determined from GC data JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 28

15 15 Tampico- Misantla Basin, Onshore Mexico Tampico-Misantla Basin Stevens and Moodhe, 2016 JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 29 Geochemical Log showing shallow Cretaceous and deeper U. Jurassic source rocks with high oil content, oil crossover, and volatile oil window maturity Depth: ft. m. Strat Lith TOC OIL (boe/af) Kerogen OSI %Roe HI OI TOC (wt.%) OIL (BOE/AF) KEROGEN (mg/g) S1/TOC (mg/g) %Roe(Tmax) HI (mg/g) OI (mg/g) PIMIENTA TAMAN JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 30

16 16 U. Jurassic System primarily organic-rich marine marls and carbonates similar to Eagle Ford, south Texas with similar TOC and HI values JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 31 Elevated Aromatics in Carbonates and Marls in U. Jurassic (also Madison Group, Williston Basin) Carbonates Marls Not evaporative fractionation Clay-rich shales For evaporative fractionation, see Thompson, 1988 JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 32

17 17 HAWK PAM can only measure what remains in sample Lost oil due to evaporation Maende, 2015 See also Shale Play Method, Romero-Sarmiento (2014) JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 33 Lost oil is demonstrated by this solvent extract of a dolomite dominated reservoir rock (core) after 1 year of storage. It has lost lost C 15 - alkanes, whereas the Bakken Shale retained to C 5 alkanes. Relative Yield (microamps) n-c 15 Middle Member of the Bakken Formation: extracted oil from core in production interval mins The lower GC fingerprint is the produced dead oil sample showing light ends similar to the high TOC shale itself. Although this contains C 5 + alkanes, it has lost some of the C 8 - fraction, again lost oil. Relative Yield (microamps) n-c 7 Oil produced from Middle Member of Bakken Formation Jarvie et al., 2011 JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 34 n-c 15 mins

18 18 Using exponential fitting and normalization of the unevaporated fraction of the extract or the oil shows the same exponential factor. Yield Restored Middle Member Oil y = e x The fitting equation enables restoration of the entire gas and oil content from either the dead oil or highly evaporated extract. This only applies to volatile oil and condensate windows Yield Carbon Number (C 1 to n-c 40 ) Restored Middle Member Extract y = e x Carbon Number (C 1 to n-c 40 ) JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 35 Illustration: Evaporative Loss of Oil (slide-1 showing loss of C 15 - alkanes) Evaporative Loss JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 36

19 19 In the Volatile Oil and Condensate Windows, alkanes that are not evaporated show exponential fit. Evaporative losses are logarithmic with good fitting results. Molar Yield Logarithmic loss with very high correlation n-alkane Carbon Number Exponential fit with very high correlation JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 37 Exponential Fitting Results of Unevaporated C 15 + Alkanes Kissin, 1987; Thompson, 2002; Holba et al., 2014 JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 38

20 20 Using the Exponential Fitting Equation Lost Oil and Gas may be restored Exponential Restoration of C 1 through C 40 Predicted in situ Gas to Oil Index: 63% Results compare favorably with PVT-recombination analysis JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 39 Cross Check: evaluate evaporative loss JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 40

21 21 Similar High Resolution Results can be achieved with Thermal Syringe FAST GC of rock thermal extracts at the well site in mins including high molecular weight wax analysis on rock extracts Jarvie et al., 2015 Waxes are not always noted in oil samples due to precipitation and poor sampling of oils. If present, they will be found in rock thermal extracts JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 41 Relationship of GOR to restored C 1 to C 5 : increasing restored C 1 to C 5, shows increasing GOR JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 42

22 22 Prediction of GOR from GC: Eagle Ford Shale using Mango and Jarvie (2001) equation C 6 -C 7 Calculated GOR Value (scf/bbl) y = x R² = Reported GOR Value (scf/bbl) JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 43 Prediction of GOR from GC: Bakken Shale Formation Production GORs ca. 400 scf/stb Jarvie et al., 2011 JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 44

23 23 Prediction of GOR from GC: Wolfcamp JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 45 Correlation of GOR to API: Mexican oils JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 46

24 24 Prediction of GOR from GC: U. Jurassic Shales, Mexico Black oil Volatile oil JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 47 There is fractionation of oil after stimulation depending on the reservoir and operating conditions of well. Post-stimulation favors production of lighter hydrocarbons. JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 48

25 25 Unconventional Plays require more precise definition of windows GOR Yield Energy Product Type scf/stb (m 3 /m 3 ) bbls/mmcf BTU (kj) Black oil < 1,000 (< 178) na na Volatile oil 1,000-3,499 ( ) >285 > 1500 Condensate-wet gas 3,500-9,999 (623-1,781) (1372) Rich wet gas 10,000-49,999 (1,781-8,905) ( ) Lean wet gas 50, ,000 (8,905-17,811) ( ) Dry gas > 100,000 (< 17,811) < 10 < 1025 (1081) Jarvie, 2017b (submitted) JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 49 Synopsis Salt withdrawal mini basins may contain potent petroleum source rocks Secondary cracking is SARA cracking (not just saturated hydrocarbon cracking) Carbonate source rocks and oils often display high aromaticity values; not indicative of evaporative fractionation There is significant unconventional resource potential onshore Tampico-Misantla basin, Mexico Restoration of lost oil may be used to determine volumetrics in a source rock as well as GOR Fractionation occurs after stimulation JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 50

26 26 REFERENCES Baker, Jr., E.T., 1995, Stratigraphic nomenclature and geologic sections of the Gulf coastal plain of Texas, U.S. Geological Survey, Open-File Report , 20p. Bruno, L., D.L. Roy, G.S. Grinsfelder, A.J. Lomando, 1991, Alabama Ferry Field U.S.A. East Texas Basin, Texas, Stratigraphic Traps II - AAPG Treatise, 27p. Burgess, J.D., 1990, Correlation of Cretaceous and Jurassic oils from Hunt and Kaufman counties, northeast Texas, GCSSEPM Foundation Ninth Annual Research Conference Proceedings, October 1, 1990, p Colorado Plateau Geosystems Inc., Deep-Time Maps (Ronald Blakey). GeoExPro, vol. 12, no. 5, 5 p. Holba, A.G., R.L. Bone, B.J. Huizinga, J.R. Vasquez, and S.M. Stokes, 2014, Petroleum-fluid property prediction from gas chromatographic analysis of rock extracts or fluid samples, U.S. Patent PCT/US2013/053461, International Publication Number WO 2014/ A2, 33p. Horsfield, B. (1989) Practical criteria for classifying kerogens: Some observations from pyrolysis-gas chromatography. Geochim. Cosmochim. Acta, 53, Horsfield, B., Disko, U. & Leistner, F. (1989) The micro-scale simulation of maturation: Outline of a new technique and its potential applications. Geologische Rundschau 78/1, Jarvie, Daniel M., Robert J. Coskey, Michael S. Johnson, and Jay E. Leonard, 2011, The Geology and Geochemistry of the Parshall Field Area, Mountrail County, North Dakota in RMAG's The Bakken-Three Forks Petroleum System in the Williston Basin, eds. John W. Robinson, Julie A. LeFever, and Stephanie B. Gaswirth, p Jarvie, D.M., B.M. Jarvie, W.D. Weldon, and A. Maende, 2015, Geochemical assessment of in situ petroleum in unconventional resource systems, URTeC paper # , 20p. Jarvie, D.M., 2017a, AAPG ACE Course Notes, AAPG ACE National Convention, Houston, Texas, April 1, 2017, 124 p. Jarvie, D.M., 2017b, Discussion: Re-evaluation of the thermal maturity of the Barnett Shale, Fort Worth Basin, (response to Lewan and Pawlewicz 2017 paper of referenced title), submitted August 2017, AAPG Bulletin. Kissin, Y. V., 1987, Catagenesis and composition of petoleum: Origin of n-alkanes and isoalkanes in petroleum crudes, Geochim. Cosmo. Acta, Vol. 51, pp Maende, A., 2015, Wildcat compositional analysis for conventional and unconventional reservoir assessments: HAWK Petroleum Assessment Method (HAWK-PAM), Wildcat Technologies Application Note ( ), accessed May 15, JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 51 Magoon, L.B., T.L. Hudson, and H.E. Cook, 2001, Pimienta-Tamabra(!) A giant supercharged petroleum system in the southern Gulf of Mexico, onshore and offshore Mexico, in C. Bartolini, R.T. Buffler, and A. Cantu-Chapa, eds., The western Gulf of Mexico Basin: Tectonics, sedimentary basins, and petroleum systems, AAPG Memoir 75, p Mango, F.D. and D.M. Jarvie, 2001, GOR from Oil Composition, 20 th International Meeting on Organic Geochemistry, Nancy, France, Sept , 2001, Abstracts Vol. 1, pp Romero-Sarmiento, M-F., D. Pillot, G. Letort, V. Lamoureux-Var, V. Beaumont, A-Y. Huc, and B. Garcia, 2015, New Rock- Eval method for characterization of unconventional shale resource systems, Oil & Gas Science and Technology, Revue IFP Energies Nouvelles, 9p. Moldowan, J. M., Dahl, J., Zinniker, D., Barbanti, S. M., 2015, Underutilized advanced geochemical technologies for oil and gas exploration and production-1. The diamondoids, Journal of Petroleum Science and Engineering, v. 126, p Pearson, K., 2012, Geologic models and evaluation of undiscovered conventional and continuous oil and gas resources Upper Cretaceous Austin Chalk, U.S. Gulf Coast:, U.S. Geological Survey Scientific Investigations Report , accessed 15 August Peel, F.J., 2014, How do salt withdrawal minibasins form? Insights from forward modelling, and implications for hydrocarbon migration, Tectonophysics, 630, p Santamaria Orozco, D.M., 2000, Organic geochemistry of Tithonian source rocks and associated oils from the Sonda de Campeche, Mexico, Ph.D thesis, Rheinisch-Westfalischen Technischen Hochschule Aachen (RWTH), 170 p. Sassen, R. and C.H. Moore, 1988, Framework of hydrocarbon generation and destruction in eastern Smackover trend, AAPG Bulletin, v. 72, no. 6, p Stevens, S. and K. Moodhe, 2016, New bid round accelerates Mexico s shale potential, Oil & Gas Journal, June 6, 2016, 9 p. Sofer, Z., 1984, Stable Carbon Isotope Compositions of Crude Oils: Application to Source Depositional Environments and Petroleum Alteration, AAPG Bull., Vol. 68, No. 1, pp Thompson, K. F. M., 1988, Gas-condensate migration and oil fractionation in deltaic systems, Marine and Pet. Geol., Vol. 5, p Thompson, K.F.M., 2002, Compositional regularities common to petroleum reservoir fluids and pyrolysates of asphaltenes and kerogens, Org. Geochem., 33, p JARVIE: CRETACEOUS AND JURASSIC SOURCE ROCKS 28 th IMOG, SEP 2017, FLORENCE, ITALY 52