Impact of Particle Crush-Size and Weight on Rock-Eval S₂, S₄, and Kinetics of Shales

Abstract

The Rock-Eval technique in the last few decades has found extensive application for source rock analysis. The impact of shale particle crush-size and sample weight on key Rock-Eval measurements, viz. the S₂ curve (heavier hydrocarbons released during the non-isothermal pyrolysis-stage) and the S₄ curve (CO₂ released from oxidation of organic matter during the oxidation-stage) are investigated in this study. For high and low total organic carbon (TOC) samples of different thermal maturity levels, it is apparent that particle crush-size has a strong influence on the results obtained from Rock-Eval analysis, with the effect being stronger in high-TOC samples. In comparison to the coarser-splits, S₂ and pyrolyzable carbon (PC) were found to be higher for the finer crush sizes in all the shales studied. The S₄CO₂ oxidation curve shapes of Permian shales show contrasting signatures in comparison to the Paleocene-aged lignitic shale, both from Indian basins. A reduced TOC was observed with rising sample weight for a mature Permian shale from the Jharia basin, while the other shales sampled showed no significant reduction. The results indicate that the S₄CO₂ curve and the S₄T_peak, are strongly dependent on the type of organic-matter present and its level of thermal maturity. Sample weight and particle size both influence the S₂-curve shapes at different heating rates. With increasing sample weights, an increase in S₂-curve magnitude was observed for the shales of diverse maturities. These differences in the S₂ curve shape lead to substantially different kinetic distributions being fitted to these curves. These findings are considered to have significant implications for the accuracy of reaction kinetics obtained from pyrolysis experiments using different sample characteristics.

Keywords

high-TOC shale analysis / Rock-Eval pyrolysis / total organic carbon / sample specifications / thermal maturity / shale reaction kinetics / petroleum geology

References

[1] Bankole S A, Buckman J, Stow D, . Automated Image Analysis of Mud and Mudrock Microstructure and Characteristics of Hemipelagic Sediments: IODP Expedition 339. Journal of Earth Science, 2019, 30(2): 407-421.

[2] Behar F, Beaumont V, de B Penteado H L. Rock-Eval 6 Technology: Performances and Developments. Oil & Gas Science and Technology, 2001, 56(2): 111-134.

[3] Bhowmick P K, Misra R. Phanerozoic Petroliferous Basins of India, 2009, New Delhi: Glimpses of Geoscience Research in India, 253-268

[4] Burnaman M D, Xia W W, Shelton J. Shale Gas Play Screening and Evaluation Criteria. China Pet. Explor., 2009, 14(3): 51-64

[5] Carvajal-Ortiz H, Gentzis T. Critical Considerations when Assessing Hydrocarbon Plays Using Rock-Eval Pyrolysis and Organic Petrology Data: Data Quality Revisited. International Journal of Coal Geology, 2015, 152: 113-122.

[6] Chatterjee G C, Ghosh P K. Tectonic Framework of the Peninsular Gondwana of India. Geol. Surv. India Record, 1970, 98(2): 1-15

[7] Chen Z H, Jiang C Q. An Integrated Mass Balance Approach for Assessing Hydrocarbon Resources in a Liquid-Rich Shale Resource Play: An Example from Upper Devonian Duvernay Formation, Western Canada Sedimentary Basin. Journal of Earth Science, 2020, 31(6): 1259-1272.

[8] Chen Z H, Jiang C Q, Lavoie D, . Model-Assisted Rock-Eval Data Interpretation for Source Rock Evaluation: Examples from Producing and Potential Shale Gas Resource Plays. International Journal of Coal Geology, 2016, 165: 290-302.

[9] Chen Z H, Liu X J, Guo Q L, . Inversion of Source Rock Hydrocarbon Generation Kinetics from Rock-Eval Data. Fuel, 2017, 194: 91-101.

[10] Chen Z H, Liu X J, Jiang C Q. Quick Evaluation of Source Rock Kerogen Kinetics Using Hydrocarbon Pyrograms from Regular Rock-Eval Analysis. Energy & Fuels, 2017, 31(2): 1832-1841.

[11] Chen, Z., Jiang, C., Chen, J., 2015. Comparison of Source Rock Kerogen Kinetics Using a Data-Driven Model and Based on Rock-Eval Pyrolysis Data. International Conference and Exhibition, Melbourne, 13–16 September 2015

[12] Espitalié J, Bordenave M L. Bordenave M L. Rock-Eval Pyrolysis. Applied Petroleum Geochemistry, 1993, Paris: Editions Technip, 237-261

[13] Espitalié J, Deroo G, Marquis F. La Pyrolyse Rock-Eval et Ses Applications. Première Partie. Revue de l’Institut Français du Pétrole, 1985, 40(5): 563-579.

[14] Espitalié J, Laporte J L, Madec M, . Méthode Rapide de Caractérisation des Roches Mètres, de Leur Potentiel Pétrolier et de Leur Degré D’ évolution. Revue de l’Institut Français du Pétrole, 1977, 32(1): 23-42.

[15] Fox C S. The Jharia Coalfield. Mem. Geol. Surv. India, 1930, 56: 253-255.

[16] Gao Z Y, Fan Y P, Xuan Q X, . A Review of Shale Pore Structure Evolution Characteristics with Increasing Thermal Maturities. Advances in Geo-Energy Research, 2020, 4(3): 247-259.

[17] Hazra B, Singh D P, Chakraborty P, . Using Rock-Eval S₄Tpeak as Thermal Maturity Proxy for Shales. Marine and Petroleum Geology, 2021, 127: 104977

[18] Hazra B, Wood D A, Mani D, . Source-Rock Evaluation Using the Rock-Eval Technique. Evaluation of Shale Source Rocks and Reservoirs. Petroleum Engineering, 2019, Switzerland: Springer

[19] Hazra B, Dutta S, Kumar S. TOC Calculation of Organic Matter Rich Sediments Using Rock-Eval Pyrolysis: Critical Consideration and Insights. International Journal of Coal Geology, 2017, 169 106-115.

[20] Hazra B, Karacan C Ö, Tiwari D M, . Insights from Rock-Eval Analysis on the Influence of Sample Weight on Hydrocarbon Generation from Lower Permian Organic Matter Rich Rocks, West Bokaro Basin, India. Marine and Petroleum Geology, 2019, 106: 160-170.

[21] Hazra B, Sarkar P, Chakraborty P, . Coal Combustion Analysis Using Rock-Eval: Importance of S₄-T Peak. Arabian Journal of Geosciences, 2020, 13(12): 1-10.

[22] Hazra B, Wood D A, Singh P K, . Source Rock Properties and Pore Structural Framework of the Gas-Prone Lower Permian Shales in the Jharia Basin, India. Arabian Journal of Geosciences, 2020, 13(13): 1-18.

[23] Inan S, Yalçin M N, Mann U. Expulsion of Oil from Petroleum Source Rocks: Inferences from Pyrolysis of Samples of Unconventional Grain Size. Organic Geochemistry, 1998, 29(1/2/3): 45-61.

[24] Jarvie, D. M., 2012a. Shale Resource Systems for Oil and Gas: Part 1—Shale-Gas Resource Systems. In: Breyer, J. A., ed., Shale Reservoirs—Giant Resources for the 21st Century. AAPG Memoir, 97: 69–87

[25] Jarvie, D. M., 2012b. Shale Resource Systems for Oil and Gas: Part 2—Shale-Oil Resource Systems. In: Breyer, J. A., ed., Shale Reservoirs—Giant Resources for the 21st Century. AAPG Memoir, 97: 89–119

[26] Lafargue E, Marquis F, Pillot D. Rock-Eval 6 Applications in Hydrocarbon Exploration, Production, and Soil Contamination Studies. Revue de l’Institut Français du Pétrole, 1998, 53(4): 421-437.

[27] Liao L L, Wang Y P, Chen C S, . Kinetic Study of Marine and Lacustrine Shale Grains Using Rock-Eval Pyrolysis: Implications to Hydrocarbon Generation, Retention and Expulsion. Marine and Petroleum Geology, 2018, 89: 164-173.

[28] Liu K Q, Zakharova N, Gentzis T, . Microstructure Characterization of a Biogenic Shale Gas Formation—Insights from the Antrim Shale, Michigan Basin. Journal of Earth Science, 2020, 31(6): 1229-1240.

[29] Liu Y M, Ye J R, Cao Q, . Hydrocarbon Generation, Migration, and Accumulation in the Eocene Niubao Formation in the Lunpola Basin, Tibet, China: Insights from Basin Modeling and Fluid Inclusion Analysis. Journal of Earth Science, 2020, 31(1): 195-206.

[30] Mathews R P, Chetia R, Agrawal S, . Early Palaeogene Climate Variability Based on N-Alkane and Stable Carbon Isotopic Composition Evidenced from the Barsingsar Lignite-Bearing Sequence of Rajasthan. Journal of the Geological Society of India, 2020, 95(3): 255-262.

[31] Padhy P K, Das S K. Shale Oil and Gas Plays: Indian Sedimentary Basins. Geohorizons, 2013, 18(1): 20-25

[32] Pashin J C. Coal as a Petroleum Source Rock and Reservoir Rock. Applied Coal Petrology, 2008, New York: Elsevier

[33] Peters K E. Guidelines for Evaluating Petroleum Source Rock Using Programmed Pyrolysis. AAPG Bulletin, 1986, 70: 318-329.

[34] Peters K E, Cassa M R. Applied Source Rock Geochemistry. In: Magoon, L. B., Dow, W. G., eds., The Petroleum System—From Source to Trap. AAPG Memoir, 1994, 60: 93-120.

[35] Peters K E, Walters C C, Mankiewicz P J. Evaluation of Kinetic Uncertainty in Numerical Models of Petroleum Generation. AAPG Bulletin, 2006, 90(3): 387-403.

[36] Raja Rao, C. S., 1983. Coal resources of Madhya Pradesh and Jammu & Kashmir. Bull. Geol. Surv. India Series A, No. 45, Coalfields of India III. 1–204

[37] Romero-Sarmiento M F, Pillot D, Letort G, . New Rock-Eval Method for Characterization of Unconventional Shale Resource Systems. Oil & Gas Science and Technology—Revue d’IFP Energies Nouvelles, 2016, 71(3): 37

[38] Schenk H J, Horsfield B. Using Natural Maturation Series to Evaluate the Utility of Parallel Reaction Kinetics Models: An Investigation of Toarcian Shales and Carboniferous Coals, Germany. Organic Geochemistry, 1998, 29 1/2/3 137-154.

[39] Singh D P, Singh V, Singh P K, . Source Rock Properties and Pore Structural Features of Distinct Thermally Mature Permian Shales from South Rewa and Jharia Basins, India. Arabian Journal of Geosciences, 2021, 14(10): 1-16.

[40] Singh D P, Hazra B, Wood D A, . Hydrocarbon Generation and Kinetics: A Case Study of Permian Shales, India. Journal of Asian Earth Sciences, 2021, 222: 104960

[41] Singh A K, Sharma M, Singh M P. Genesis of Natural Cokes: Some Indian Examples. International Journal of Coal Geology, 2008, 75(1): 40-48.

[42] Singh A K, Sharma M, Singh M P. SEM and Reflected Light Petrography: A Case Study on Natural Cokes from Seam XIV, Jharia Coalfield, India. Fuel, 2013, 112 502-512.

[43] Singh P K, Rajak P K, Singh M P, . Environmental Geochemistry of Selected Elements in Lignite from Barsingsar and Gurha Mines of Rajasthan, Western India. Journal of the Geological Society of India, 2015, 86(1): 23-32.

[44] Singh P K, Rajak P K, Singh V K, . Studies on Thermal Maturity and Hydrocarbon Potential of Lignites of Bikaner-Nagaur Basin, Rajasthan. Energy Exploration & Exploitation, 2016, 34(1): 140-157.

[45] Sinha-Roy, S., Malhotra, G., Mohanti, M., 1998. Geology of Rajasthan. Geological Society of India, Bangalore. 278

[46] Stoneley, R., Selley, R., 1996. A Review of the Petroleum Prospects of the South Rewa, Satpura and Hasdeo-Mahanadi Gondwana Basins and Deccan Syneclise. Unpub. ONGC Report, 1–65

[47] Tissot B P, Welte D H. Petroleum Formation and Occurrence: A New Approach to Oil and Gas Exploration, 1978, Berlin, Heidelberg, New York: Springer-Verlag

[48] Varma A K, Hazra B, Mendhe V A, . Assessment of Organic Richness and Hydrocarbon Generation Potential of Raniganj Basin Shales, West Bengal, India. Marine and Petroleum Geology, 2015, 59: 480-490.

[49] Wood D A. Relationships between Thermal Maturity Indices of Arrhenius and Lopatin Methods: Implications for Petroleum Exploration. American Association of Petroleum Geologists Bulletin, 1988, 72: 115-135.

[50] Wood D A. Establishing Credible Reaction-Kinetics Distributions to Fit and Explain Multi-Heating Rate S2 Pyrolysis Peaks of Kerogens and Shales. Advances in Geo-Energy Research, 2019, 3(1): 1-28.

[51] Wood D A, Hazra B. Characterization of Organic-Rich Shales for Petroleum Exploration & Exploitation: A Review-Part 2: Geochemistry, Thermal Maturity, Isotopes and Biomarkers. Journal of Earth Science, 2017, 28(5): 758-778.

[52] Wu Z R, He S, Han Y J, . Effect of Organic Matter Type and Maturity on Organic Matter Pore Formation of Transitional Facies Shales: A Case Study on Upper Permian Longtan and Dalong Shales in Middle Yangtze Region, China. Journal of Earth Science, 2020, 31(2): 368-384.