Geochemical Evaluation of the Hydrocarbon Potential of Shale Oil and Its Correlation with Different Minerals–a Case Study of the TYP Shale in the Songliao Basin, China

Abstract

Based on routine Rock-Eval experiments conducted on the source rock and dichloromethane-extracted portions of the same samples, total oil yield was calculated and compared with those obtained from the classic calculation equations. For shale in the early maturity and oil window, there is a large quantity of heavy constituents in the adsorbed state due to the carry-over and confinement effect, which leads to a lower calculated total oil yield. Therefore, S 1e should be counted in the total oil yield when calculating the total oil yield. The original TOC was restored through a series of calculations. The ratio of the original TOC to the present-day TOC is between 1 and 1.79, with an average of 1.28. Therefore, it is not necessary to restore the original TOC through a series of complex calculations for shale source rocks with low to medium maturities and high residual TOC. Total oil yield is correlated with the siliceous and clay mineral to some extent, but it is poorly correlated with the carbonate mineral. Some special forms of organic sulfur may help enhance kerogen conversion to oil, which facilitates the shale to produce more oil during the early hydrocarbon generation stage.

Quantitative Measurement of Retained Oil in Organic-Rich Shale—A Case Study on the Chang 7 Member in the Ordos Basin, China

“…Finally, pyrolysis experiment was done for the third time (Sun et al, 2019;Hou et al, 2020). The results are denoted as S 21 , S 22 , and T max2 (Table 2).…”

“…Since the groundbreaking progress made by the United States on shale oil in Bakken reserves in the 1950s, technology related to shale oil in the US has been developing rapidly and achieved its profitability in 2018 (Soeder, 2018;Hackley et al, 2020;Solarin et al, 2020;Ulrich-Schad et al, 2020). Drawing lessons from the experience of the USA's shale oil development, China began to explore the technology and practice on shale oil exploration and development and made a step forward on fields including geological theory, exploration and development technology, and experimental techniques (Hou et al, 2020;Hou et al, 2021a;Kang et al, 2020;Ma et al, 2020a;Ma et al, 2020b;Zhao et al, 2020a;Zhu et al, 2021). However, more researches are needed to tackle problems related to the quantitative evaluation of the total retained oil content, the occurrence mechanism of shale oil, and pores and fluid flowing mechanism in shale formation.…”

“…Therefore, they are treated as free shale oil. However, S 1 does not represent all free shale oil and S 2 does not completely show the hydrocarbon potential in kerogen (Chen et al, 2018;Li et al, 2018;Li M. W. et al, 2019;Ma et al, 2019;Hou et al, 2020). S 2 contains small amounts of free oil and absorbed oil, so the pyrolysis method cannot estimate the content of absorbed shale oil.…”

Identification of Oil Produced from Shale and Tight Reservoirs in the Permian Lucaogou Shale Sequence, Jimsar Sag, Junggar Basin, NW China

“…The exploration and commercial development of shale oil have expanded rapidly in many countries in recent years. 1 − 5 In 2019, the daily crude oil production in the USA, for example, was 12.26 MMb d –1 , of which 65.17% or 7.99 MMb d –1 was produced from shale sequences. 6 Large shale oil resources have recently been discovered in Chinese lacustrine basins with organic-rich shale and strongly heterogeneous sequences, such as in the Ordos, Songliao, Junggar, and Bohai Bay basins.…”

Experimental Methods for the Quantitative Assessment of the Volume Fraction of Movable Shale Oil: A Case Study in the Jimsar Sag, Junggar Basin, China

“…Shale oil has drawn a great deal of attention in terms of the global exploration and production of unconventional oil and gas (Goodarzi, 2020;Kim and Shin, 2020;Solarin, 2020;Kara and Isik, 2021). China's terrestrial shale oil has a huge resource potential, and breakthroughs have been achieved in the Permian Lucaogou Formation in the Jimsar Sag, Junggar Basin, as well as in the Chang 7 Member in the Ordos Basin (Hou et al, 2020a(Hou et al, ,b, 2021Hu et al, 2020;Ma et al, 2020;Zhao et al, 2020). However, the shale oil is only in its initial stage and is under geological conditions that are dramatically different from those of the marine shale oil in North America.…”