Estimation of Enriched Shale Oil Resource Potential in E2s4L of

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Estimation of Enriched Shale Oil Resource Potential in E2s4L of Damintun Sag in Bohai Bay Basin, China Guohui Chen, Shuangfang Lu, Junfang Zhang, Min Wang, Jinbu Li, Chenxi Xu, Marina Pervukhina, and Jiao Wang Energy Fuels, Just Accepted Manuscript • DOI: 10.1021/acs.energyfuels.6b03201 • Publication Date (Web): 16 Mar 2017 Downloaded from http://pubs.acs.org on March 18, 2017

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Estimation of Enriched Shale Oil Resource Potential in E2s4L of Damintun Sag in Bohai Bay Basin, China Guohui Chen1,2,3,4, Shuangfang Lu1,2,4*, Junfang Zhang3†, Min Wang 1,2,4 , Jinbu Li 1,2,4, Chenxi Xu1,2,4, Marina Pervukhina3, Jiao Wang2 1

Research Institute of Unconventional Oil & Gas and Renewable Energy (RIUE), China

University of Petroleum (East China), Qingdao 266580, Shandong, PR China 2

School of Geosciences, China University of Petroleum (East China), Qingdao 266580,

Shandong, PR China 3

4

CSIRO Energy, 26 Dick Perry Ave, WA 6151, Australia Shaanxi Province key laboratory of lacustrine shale gas accumulation and

development, xi’an 710000, Shaanxi, PR China

*

Dr. Lu Shuangfang Research Institute of Unconventional Petroleum and Renewable Energy (RIUP&RE), China University of Petroleum (East China), Qingdao, Shandong, China Phone (or Mobile) No.: +86-18661856596 Email: [email protected] † Dr. Junfang Zhang CSIRO Energy, ARRC, 26 Dick Perry Avenue, Kensington, Perth WA 6151, Australia Phone (or Mobile) No.: +61-0424072506 Email: [email protected] 1 ACS Paragon Plus Environment

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Abstract: The qualitative and quantitative evaluations of the resource potential are of significant importance for both exploration and exploitation of shale oil. We investigate the shale oil resource potential in E2s4L (the lower sub-member of the fourth member of the Paleogene Shahejie Formation) of Damintun Sag by both qualitative and quantitative methods. From the view point of qualitative evaluation, the target shale, with adequate oilprone organic matter (OM) in the peak and late oil generation stage, is hopeful to form a shale oil reservoir. The total oil content in shale is evaluated from free hydrocarbons in shale (S1) by correcting the heavy and light hydrocarbons and the resins and asphaltenes. The total oil content is found to be over 4.45 times as large as the original S1. The evaluation threshold of high-abundant oil is determined by both the total oil content (ST) and the ratio of ST to the total organic carbon content (TOC) with the value that larger than 8 mg/g and 1, respectively. Based on the total oil content in shale and the evaluation threshold of high-abundant oil, the resource potential of high-abundant shale oil is obtained to be around 2.2×108 t. The average oil-bearing rate is about 0.033 m3/m3, which is equivalent to Upper and Lower Bakken shale, and much higher than that of the Middle Bakken shale. From the view point of the resource potential and the oil bearing rate, the shale oil in E2s4L of Damintun Sag is found to be promising. The evaluation results and the methods to correct the S1 and to determine the highabundant oil threshold are of practical importance for shale reservoir development. Key words: Shale oil; heavy hydrocarbon correction; light hydrocarbon correction; resin and asphaltene correction; evaluation threshold; high-abundant oil; resource potential.

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Introduction Inspired by the great success of shale gas exploration and development in North America1-6, close attention is focused now on unconventional energy resources, including shale oil7-11. Shale oil has huge resource potential with estimated reserves of 345 billion barrels located across 41 countries, including 32 billion barrels in China12. Damintun Sag is located in Liaohe Depression, Bohai Bay, in China. In E2s4L (the lower sub-member of the fourth member of the Paleogene Shahejie Formation) shale of Damintun Sag, well S224 was producing 16.2 t oil per day from May 2010 to July 2011, and good oil and gas shows are observed according to the gas logging at over 50 wells across the region, highlighting the promise of the area. However, the shale oil resource potential has not been carefully evaluated. Both qualitative and quantitative evaluations for the shale oil in E2s4L of Damintun Sag are therefore urgently needed. When estimating the shale oil resource potential, the free hydrocarbons mass fraction, S1, measured in the pyrolysis experiment are usually used to represent the oil content in shale7, 8. However, some free heavy hydrocarbons in shale cannot be detected via S1 as they do not totally evaporate at the temperatures below 300 ˚C, while some light hydrocarbons are lost when transporting the core from its location in the well to the ground and during the longtime storage process in the core library13-16. Also, the resins and asphaltenes cannot be detected by the hydrogen flame ionization in the pyrolysis experiment. As a result, S1 significantly underestimates the total oil content, and must be corrected if used to evaluate the total oil content in shale. Even though the correction of S1 has been investigated in the previous studies13, 14, a further examination is needed as it is usually corrected to the total hydrocarbon content rather than the total oil content in previous studies to the best of our knowledge.


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Even though the total oil content in shale evaluated based on the correction of S1 may be high, not all the oil in shale can be exploited successfully. Due to the low porosity and permeability of shale and the high density and viscosity of oil in shale, only high-abundant oil may be developed by the hydraulic fracturing of horizontal wells17. Therefore, the evaluation of the high-abundant oil content is of significant importance, and the evaluation threshold need to be determined firstly. In previous studies 7, 8, 18, the S1 and TOC were usually used to represent the total oil content in shale and the oil-bearing capacity of shale, respectively, and their relationship was used to design the evaluation threshold. However, S1 cannot reflect the total oil content in shale as discussed before. Therefore, a more reasonable method is needed to design the evaluation threshold of the high-abundant oil. In this study, we evaluate the shale oil resource potential in E2S4L of Damintun sag both qualitatively and quantitatively. In the quantitative evaluation, we build the methods to correct S1 with heavy and light hydrocarbons and with resins and asphaltenes, and build a method to design the evaluation threshold of high-abundant oil. Finally, the resource potential and the oil-bearing rate are evaluated. We hope the evaluation is helpful to future exploration and exploitation of shale oil in the target area, and the methods to correct S1 and to design the evaluation threshold of high-abundant oil would be useful for the shale oil evaluation in the future.


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Geological setting Damintun Sag is located in the northeast of Liaohe Depression in the Bohai Bay Basin (as shown in Figure 1)19, 20. It forms an irregular-shaped triangle wide in the south and narrow in the north covering an area of about 800 km2. Damintun Sag is a composite extension and strike-slip sag developed on the base of early rift valley. Its main structure and evolution features are consistent with dextral strike-slip activity of the Tan-Lu fault.

Figure 1. a. Regional structural map for the Liaohe Depression showing the location of Damintun Sag; b. structural map showing a variety of faults and oil production wells.

The breakdown during the depositional stages of E2s4 (the fourth member of the Paleogene Shahejie Formation) was strong with obvious inheritance21. The E2s4 mainly developed in the lake system, forming a set of dark and fine sediments with the thickness of 5 ACS Paragon Plus Environment

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300 - 1600 m (as shown in Figure 2). During the early stage of the deposition of E2s4, the climate was warm and humid, and most of the sag was covered by the brackish water with the reducing environment, forming a large amount of the bacteria, algae and other underwater organisms and low plankton, and in turn forming a set of black shale with a high abundance of organic matters in the lower member of E2s4 (E2s4L)21, which is the target member in this study (as shown in Figure 2).


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Figure 2. The Shahejie stratigraphic column, Damintun Sag.


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Samples and methods Totally 85 lacustrine shale core samples from E2s4L of Damintun Sag were selected for this study. All the samples were taken from 9 wells with the depth between 2400 m and 3700 m. All the samples were powdered to 80-100 mesh after surface cleaning. Total organic carbon content (TOC) of about 100 mg sample was measured by the Leco C230 carbon analyzer after removing carbonates by the 5% hydrochloric acid at the temperature of 80 ˚C. The Rock-Eval 6 instrument was used to carry out pyrolysis analysis on the crushed sample weighting about 70 mg. The pyrolysis involved an initial temperature of 300 ˚C maintained for 3 min to release free hydrocarbons (S1), followed by ramping the temperature up to 650 ˚C by 25 ˚C/min to release hydrocarbons from the remaining organic matter (OM) by thermal cracking (S2)22. To remove the oil in shale, we extracted 37 of the powdered samples using chloroform by Soxhlet extraction method at the temperature of 70 ˚C for more than 72 hours. Then perform the pyrolysis experiment on the extracted samples to obtain the hydrocarbon mass fraction in the temperature from 300 ˚C to 650 ˚C (S2′). In addition, we extracted 19 of the samples and perform the gas chromatographic analyses to obtain the group composition of the oil. To investigate the maturity of the target shale, 48 shale samples were selected to measure the vitrinite reflectance index (Ro) using the UMSP-50 microphotometer. The immature shale sample from well A17 was selected to perform the hydrocarbon generation experiment in the open system using the Rock-Eval 6 instrument23. We heated the powdered samples from 200 ˚C to 650 ˚C at a heating rate of 10 ˚C/min and 20 ˚C/min, respectively, and recorded the mass fraction of the hydrocarbon products in real-time. Then we ran Py-GC analysis on powdered sample from 200 ˚C to 630 ˚C at a heating rate of 10 ˚C/min and 20 ˚C/min, respectively. The pyrolysis products were swept by a helium flow of 50 ml/min to an outside cold trap. We collected the products from the cold trap per 50 ˚C 8 ACS Paragon Plus Environment

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from 200 ˚C to 300 ˚C and per 30 ˚C from 300 ˚C to 630 ˚C, and we performed the gas chromatographic analysis on the thermal degradation products to measure the proportion of gas hydrocarbon (C1-5), the light hydrocarbon (C6-13) and the heavy hydrocarbon (C13+). Finally, we combined the measurements of the Rock-Eval and Py-GC to calculate the generation amount of different hydrocarbon compositions at varying temperatures under different heating rates.


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Results and discussions Geochemical characteristics Evaluation of the geochemical characteristics of organic matter (OM) in shale can give a general guidance for the resource potential evaluation of shale oil, therefore, we firstly characterized the OM.

The abundance of OM. The abundance of OM, which represents the oil generation potential, is evaluated by the parameters of TOC and cracking hydrocarbon (S2) (as shown in Figure 3). The TOC of shale samples ranges from 0.47 to 14 wt. %, with average of 6.45 wt. %. According to Figure 3a, the percentage of the samples with the TOC between 2 wt. % and 4 wt. % is larger than 12 %, and that with the TOC value larger than 4 wt. % is larger than 75 %. The shale has been categorized as “very good” and “excellent” according to the quantity of OM with the TOC ranging from 2 wt. % to 4 wt. % and with the TOC greater than 4 wt.%, respectively24. Therefore, the most shale samples in E2s4L of Damintun Sag have “very good” and “excellent” quantity of OM. The S2, which is the pyrolytic products detected as the crushed sample is heated after 300 ˚C in the pyrolysis experiment, is conventionally used to evaluate the generative potential of shale. The S2 of the shale in E2s4L of Damintun Sag ranges from 1.9 mg/g to 79.83 mg/g, averages on 33.04 mg/g. According to the category of OM by its quantity 24, more than 12% of the samples with the S2 between 10 mg/g and 20 mg/g can be sorted as “very good” in quantity of OM, and more than 70% of the samples with the S2 larger than 20 mg/g can be classified as “excellent” (as shown in Figure 3b). The evaluation results of the abundance of OM from the TOC and the S2 consistent with each other very well, both indicating the high abundance of OM in the shale samples from E2s4L of the Damintun Sag.


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Frequency of TOC (%)

30

a.

n=85 Ave. TOC=6.45 %

25 20 15 10 5 0 = +@ABCD EDF GBHIEJKADA//ILFMNOEMPND ∙ + + ∙ /


(10)

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R(Resin + asphaltene)/ hydrocarbon 0

1

2

3

4

2000 2200

n=19

2400

Depth (m)

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2600 2800 3000 3200 3400

Figure 9. The profile of the ratio of resins and asphaltenes to hydrocarbons in chloroform extractions.

Correction results. Having calculated the amount of lost heavy and light hydrocarbons

and the amount of the resins and asphaltenes based on S1, we can evaluate the total oil content in shale (ST, mg/g rock) by adding them to S1. The ST versus S1 plot is shown in Figure 10, which shows a strong linear relation between ST and S1 with the correlation coefficient R2 of 0.97. The slope of the regression line is 4.45, suggesting that the total oil content in shale is more than 4.45 times as large as S1, which further confirmed our argument that the correction is necessary when using S1 to evaluate the total oil content in shale.


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n=85 y = 4.45 x + 0.22 R² = 0.97

20 15 10 5 0 0

1

2

3

4

5

6

S1 (mg/g) Figure 10. ST versus S1 plot showing the distinction between the total oil content and S1.

Evaluation threshold of high-abundant oil Even though the total oil content in shale evaluated by ST may be very high, the recoverable resource potential is usually low, because of the low porosity and permeability of shale and the high density and viscosity of oil in shale. Considering the oil property is similar in the same sag, only the oil with higher abundance may be hopefully exploited. Since the evaluation of the high-abundant oil resource potential is of significant importance, the evaluation threshold of high-abundant oil need to be designed. The TOC is considered to be important for the oil-bearing potential of shale because of its contribution to oil generation and its adsorption capacity, and S1 is usually used to represent the oil content in shale. The relationship between TOC and S1 was usually used to determine the evaluation threshold of high-abundant oil in previous studies7, 18. Considering that the S1 cannot reflect exactly the total oil content in shale as discussed in previous section, we use the total oil content instead of S1 when investigating the evaluation threshold of highabundant oil. The ST versus TOC plot is presented in Figure 11, in which the outside envelope


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curve of ST generally increases with the TOC. The outside envelope curve of ST increases slowly as the TOC is smaller than 4 %, while it increases sharply as the TOC is larger than 4 %, and then forms a platform. In other words, the outside envelope of ST inflects when ST is 8 mg/g and TOC is 4%.We infer that both the oil generation and oil bearing capacity are not large enough to form the high-abundant oil as the TOC is smaller than 4%, resulting the ST lower than 8 mg/g as. However, the comprehensive effects of the oil generation capacity and the oil bearing capacity change sharply as TOC is around 4 %, forming the high-abundant oil with the ST larger than 8 mg/g as TOC is larger than 4 %. We take the inflection with the ST of 8 mg/g as the evaluation threshold of high-abundant oil. In addition, the recoverability has been successfully related to the ratio between oil content and TOC in previous study7, in which the ratio larger than 1 indicates a good recoverability. This is due to the fact that the organic carbon has a strong adsorption capacity, only when the oil content is larger than the adsorption capacity, the oil can be successfully exploited. Therefore, from the view point of both the total oil content and the recoverability, we define the oil in shale with the ST larger than 8 mg/g and the ST/TOC larger than 1 as the high-abundant oil in this study. According to our evaluation method, the data of well S224 is the high-abundant oil (as shown in Figure 11), which further confirms the feasibility of our investigation.


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ST (mg Oil/g Rock)

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High-abundance oil Scattered oil Outside Envelope Curve

24 ST/TOC = 1

n=85

16

Well S224

8 ST = 8 mg/g

0 0

2

4

6

8

10

12

14

TOC (%) Figure 11. ST versus TOC plot showing the determination of the evaluation threshold of high-abundant oil.

Shale oil resource potential evaluation According to the threshold of high-abundant oil, we can approximately identify the region of the high-abundant oil. The high- abundant shale oil resource potential can be obtained by the following equation:

Q = 10 × × × R × 2

(11)

where Q is the shale oil resource potential in the unit of ton. The area (S) and thickness (H) of shale are 105 km2 and 75 m, respectively, forming the volume of the shale to be 7.9×109 m3. The density of the shale (ρ) is 2.65 g/cm3. The resource potential of the high-abundant oil is about 2.2×108t. The average oilbearing rate is about 0.033 m3/m3, which is equivalent to that of the Upper and Lower Bakken shale with the value of 0.031 m3/m3, and much higher than that of the Middle Bakken shale with the value of 0.007 m3/m3 7, 8. From the view point of the resource potential and the oil bearing rate, the shale oil in E2s4L of Damintun Sag is promising and worthy for attention.


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Conclusions In this paper, we investigated the shale oil resource potential in E2s4L of Damintun Sag by the qualitative evaluation of the geochemical characteristics of OM and the quantitative estimation of the relatively enriched shale oil resource potential, in which the total oil content in shale was evaluated based on the pyrolysis parameter of S1 and the evaluation threshold of high-abundant oil was determined by ST and the ratio of ST to TOC. The main findings are concluded as follows: (1) The oil generation amount of the shale in E2s4L of Damintun Sag, with adequate oilprone OM in the peak or late oil generation stage, is considerable and hopeful to form a shale oil reservoir. (2) The correction of heavy and light hydrocarbons and the correction of resins and asphaltenes are necessary when using the pyrolysis parameter S1 to evaluate the total oil content in shale. By the correction method build in this study, the total oil contents of shale samples are obtained, which is more than 4.45 time as large as S1. (3) The evaluation threshold of the high-abundant oil is designed by the ST and the ratio of ST to TOC with the value larger than 8 mg /g and 1, respectively. (4) The shale oil resource potential in E2s4L of Damintun Sag is promising and worthy for attention, with the relatively enriched shale oil resource potential of about 2.2×108t and the average oil-bearing rate of about 0.033 m3/m3. The evaluation result of the shale oil resource potential is hopefully to be conducive for the future exploration and exploitation of shale oil in E2s4L of Damintun Sag. The methods to correct S1 with the heavy and light hydrocarbons and with the resins and asphaltenes and the method to design the evaluation threshold of the high-abundant oil built up in this study could be hopefully expected to provide reference for the future investigation on shale oil.


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Acknowledgements This study was partly funded by National Natural Science Foundation of China (41330313, 41272152, 41172134), the Fundamental Research Funds for the Central Universities (13CX05013A, 15CX06013A), Post-graduate Innovation Project (YCX2015002), Innovation Fund of CNPC (2011D-5006-0101) and Scientific and technological research projects of Sinopec (p14068). The first author would like to acknowledge the China Scholarship Council (CSC) for its financial support for his living expenses at CSIRO in Australia as a visiting Ph.D. student. We would also gratefully acknowledge Dr. Clennell Ben for providing the visiting chance and the scientific condition for the first author.

Declarations Conflict of interest: We declare that we have no financial or personal relationships with other people or organizations that can inappropriately influence our work, there is no professional or other personal interest of any nature or kind in any product, service and/or company that could be construed as influencing the position presented in, or the review of, the manuscript entitled, “Estimation of Enriched Shale Oil Resource Potential in E2s4L of Damintun Sag in Bohai Bay Basin, China”. Ethical approval: Not required

Author contributions Guohui Chen wrote the main manuscript. Shuangfang Lu defined (supervisor in China) the statement of problem. Min Wang and Junfang Zhang provided the main idea and helped to draft the manuscript. Marina Pervukhina (supervisor in Australia) (supervisor in Australia) designed and supervised the project. Jinbu Li, Chenxi Xu and Jiao Wang processed data and plotted figures. All authors reviewed the manuscript.


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References (1) Badics, B.; Vető, I., Source rocks and petroleum systems in the Hungarian part of the Pannonian Basin: The potential for shale gas and shale oil plays. Marine & Petroleum Geology, 2012, 31 (1), 53–69. (2) Bowker, K.A., Barnett Shale gas production, Fort Worth Basin: Issues and discussion. Aapg Bulletin, 2007, 91 (4), 523-533. (3) Horsfield, B.; Schulz, H.M., Shale gas exploration and exploitation. Marine & Petroleum Geology, 2012, 31 (1), 1-2. (4) Jarvie, D.M.; Hill, R.J.; Ruble, T.E.; Pollastro, R.M., Unconventional shale-gas systems: The Mississippian Barnett Shale of north-central Texas as one model for thermogenic shale-gas assessment. Aapg Bulletin, 2007, 91 (4), 475-499. (5) Ross, D.J.K.; Bustin, R.M., Characterizing the shale gas resource potential of Devonian-Mississippian strata in the Western Canada sedimentary basin: application of an integrated formation evaluation. AAPG Bulletin, 2008, 92 (1), 87-125. (6) Zou, C.; Dong, D.; Wang, S.; Li, J.; Li, X.; Wang, Y.; Li, D.; Cheng, K., Geological characteristics and resource potential of shale gas in China. Petroleum Exploration & Development, 2010, 37 (6), 641-653. (7) Jarvie, D.M., Shale Resource Systems for Oil and Gas: Part 1—Shale-gas Resource Systems. Aapg Memoir, 2012, 97, 69-87. (8) Jarvie, D.M., Shale resource systems for oil and gas: Part 2: Shale-oil resource systems. Aapg Memoir, 2012, 97, 89-119. (9) Kinley, T.J.; Cook, L.W.; Breyer, J.A.; Jarvie, D.M.; Busbey, A.B.; Kinley, T.J.; Cook, L.W.; Breyer, J.A.; Jarvie, D.M., Hydrocarbon potential of the Barnett Shale (Mississippian), Delaware Basin, west Texas and southeastern New Mexico. Aapg Bulletin, 2008, 92 (8), 967-991. (10) Kirschbaum, M.A.; Mercier, T.J., Controls on the deposition and preservation of the Cretaceous Mowry Shale and Frontier Formation and equivalents, Rocky Mountain region, Colorado, Utah, and Wyoming. Aapg Bulletin, 2013, 97 (6), 899-921. (11) Kuhn, P.P.; Primio, R.D.; Hill, R.; Lawrence, J.R.; Horsfield, B., Threedimensional modeling study of the low-permeability petroleum system of the Bakken Formation. Aapg Bulletin, 2012, 96 (10), 1867-1897. (12) Kuuskraa, V.; Stevens, S.H.; Moodhe, K.D., Technically recoverable shale oil and shale gas resources: an assessment of 137 shale formations in 41 countries outside the United States, 2013. (13) Zhang, L.Y.; Zheng, L.I.; Li., J.Y.; Zhu, R.F.; Sun, X.N., Feasibility Analysis of Existing Recoverable Oil and Gas Resource in the Palaeogene Shale of Dongying Depression. Natural Gas Geoscience, 2012, 23 (1) 1-13. (14) Wang, M.; Tian, S.; Chen, G.; Xue, H.; Huang, A.; Wang, W., Correction Method of Light Hydrocarbons Losing and Heavy Hydrocarbon Handling for Residual Hydrocarbon (S1) from Shale. Acta Geologica Sinica (English Edition), 2014, 88 (6), 1792-1797. (15) Zhu, R.; Zhang, L.; Li, J.; Liu, Q.; Li, Z.; Wang, R.; Zhang, L., Quantitative evaluation of residual liquid hydrocarbons in shale. Acta Petrolei Sinica, 2015, 36(1),13-18. (16) Jiang, C.; Chen, Z.; Mort, A.; Milovic, M.; Robinson, R.; Stewart, R.; Lavoie, D., Hydrocarbon evaporative loss from shale core samples as revealed by Rock-Eval and thermal desorption-gas chromatography analysis: Its geochemical and geological implications. Marine And Petroleum Geology, 2016, 70, 294-303. (17) Zhang, J.C.; Bo, X.U.; Nie, H.K.; Wang, Z.Y.; Lin, T., Exploration potential of shale gas resources in china. Natural Gas Industry, 2008, 28 (6), 136-140. 27 ACS Paragon Plus Environment

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(18) Lu, S.F.; Huang, W.B.; Chen, F.W.; Li, J.J.; Wang, M., Xue, H.T.; Wang, W.M.; Cai, X.Y., Classification and evaluation criteria of shale oil and gas resources: Discussion and application. Petroleum Exploration & Development, 2012, 39 (2), 268-276. (19) Xie, W.Y.; Jiang, J.Q.; Zhang, Z.W.; Qiu, F., The petroleum system in the Damingtun Sag, Liaohe Oilfield. Petroleum Exploration & Development, 2004, 31(2), 38-42. (20) Shi, J.N.; Jiang, J.Q.; Li, M.K., Characteristics of fluid chemical field and significance of reservoir formaton in damintun depression,liaoning province. Geological Science & Technology Information, 2004, 23 (1), 63-68. (21) Chen, Z.Y., Damintun Depression fine exploration practice and understanding. Petroleum Industry Presss Pub: Beijing, 2007. (22) Behar, F.; Beaumont V.; Penteado H., Rock-Eval 6 Technology: Performances and Developments. Oil & Gas Science & Technology, 2015, 56 (2), 111-134. (23) Tissot, B.P.; Welte, D.H., Petroleum formation and occurrence. Springer Science & Business Media: 2013. (24) Peters, K.E.; Cassa, M.R., Applied Source Rock Geochemistry: Chapter 5: Part II. Essential Elements. 1994. (25) Cornford, C.; Gardner, P.; Burgess, C., Geochemical truths in large data sets. I: Geochemical screening data. Organic Geochemistry, 1998, 29 (1-3), 519-530. (26) Pittion, J.; Pradier, B., Reflectance of vitrinite as a control of thermal history of sediments, Thermal Modeling in Sedimentary Basins: 1st IFP Exploration Research Conference, Carcans, France, June 3-7, 1985, Éditions Technip, 1986, pp. 441. (27) Lo, H.B., Correction criteria for the suppression of vitrinite reflectance in hydrogen-rich kerogens: preliminary guidelines. Org. Geochem, 1993, 20, 653–657. (28) Wang, A., Calibration of analytic parameters for pyrolytic chromatography. Petroleum Geology & Expeximent, 1987, 9, 342-350. (29) Lu, S.F., Kinetics theory of hydrocarbon generation from organic matter and its application. Petroleum Industry Press Pub: Beijing, 1996. (30) Lu, S.F.; Fu, X.; Chen, X.; Qu, J.; Xue, S., Chemical kinetic models of generation of gas by various groups in crude oil and their calibration. Acta Geologica Sinica, 1997, 71 (4), 365-373. (31) Burnham, A.K.; Sweeney, J.J., A chemical kinetic-model of vitrinite maturation and reflectance. Geochimica Et Cosmochimica Acta, 1989, 53 (10), 2649-2657. (32) Sweeney, J.J.; Burnham, A.K., evaluation of a simple-model of vitrinite reflectance based on chemical-kinetics. Aapg Bull, 1990, 74 (10), 1559-1570.


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Energy & Fuels

Figure 1. a. Regional structural map for the Liaohe Depression showing the location of Damintun Sag; b. structural map showing a variety of faults and oil production wells. Damintun Sag is located in the 528x445mm (300 x 300 DPI)

ACS Paragon Plus Environment

Energy & Fuels

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Figure 2. The Shahejie stratigraphic column, Damintun Sag. The breakdown during the depos 218x463mm (300 x 300 DPI)


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Energy & Fuels

Figure 3. The histograms of (a) TOC and (b) S2 of the shale in E2s4L of Damintun Sag. The abundance of OM, which rep 129x183mm (300 x 300 DPI)


Energy & Fuels

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Figure 4. The type of OM. (a). S2 versus TOC plot, in which the blue circles are the sample values, and the red dot line is the regression curve. (b). Hydrogen index (HI) versus Tmax plot showing the type of OM, in which the blue circles are the sample values, and the black solid lines are the dividing line of the OM types. The type of OM largely determi 129x179mm (300 x 300 DPI)


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Energy & Fuels

Figure 5. The maturity of OM, (a) The vitrinite reflectance index profile, and (b) Tmax profile. The blue circles are indicative of the sample values, the red dot-dash line is the trend of the Ro, and the black dot lines are the dividing lines of oil generation stage. According to Ro and Tmax profi 172x129mm (300 x 300 DPI)


Energy & Fuels

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Figure 6. The heavy hydrocarbon (∆S2) versus S1 plot. The relationship between ∆S2 129x90mm (300 x 300 DPI)


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Energy & Fuels

Figure 7. The histogram of activation energies for both the primary and secondary cracking processes. The chemical kinetics paramete 129x90mm (300 x 300 DPI)


Energy & Fuels

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Figure 8. The light hydrocarbon correction coefficient (KL) at varying Easy Ro. By combining the chemical kine 129x90mm (300 x 300 DPI)


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Energy & Fuels

Figure 9. The profile of the ratio of resins and asphaltenes to hydrocarbons in chloroform extractions. To investigate the ratio of re 85x126mm (300 x 300 DPI)


Energy & Fuels

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Figure 10. ST versus S1 plot showing the distinction between the total oil content and S1. The ST versus S1 plot is shown 129x90mm (300 x 300 DPI)


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Energy & Fuels

Figure 11. ST versus TOC plot showing the determination of the evaluation threshold of high-abundant oil. Considering that the S1 cannot 129x90mm (300 x 300 DPI)


Estimation of Enriched Shale Oil Resource Potential in E2s4L of

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