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Petroleum Geology Features and Research Developments of Hydrocarbon Accumulation in Deep Petroliferous Basins

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Petroleum Geology Features and Research Developments of Hydrocarbon Accumulation in Deep Petroliferous Basins Pet. Sci. (2015) 12:1–53 DOI 10.1007/s12182-015-0014-0 REVIEW Petroleum geology features and research developments of hydrocarbon accumulation in deep petroliferous basins Xiong-Qi Pang • Cheng-Zao Jia • Wen-Yang Wang Received: 26 September 2014 / Published online: 3 February 2015 Ó The Author(s) 2015. This article is published with open access at Springerlink.com Abstract As petroleum exploration advances and as most the burial depth. (5) There are many types of rocks in deep of the oil–gas reservoirs in shallow layers have been hydrocarbon reservoirs, and most are clastic rocks and explored, petroleum exploration starts to move toward deep carbonates. (6) The age of deep hydrocarbon reservoirs is basins, which has become an inevitable choice. In this widely different, but those recently discovered are pre- paper, the petroleum geology features and research pro- dominantly Paleogene and Upper Paleozoic. (7) The gress on oil–gas reservoirs in deep petroliferous basins porosity and permeability of deep hydrocarbon reservoirs across the world are characterized by using the latest differ widely, but they vary in a regular way with lithology results of worldwide deep petroleum exploration. Research and burial depth. (8) The temperatures of deep oil–gas has demonstrated that the deep petroleum shows ten major reservoirs are widely different, but they typically vary with geological features. (1) While oil–gas reservoirs have been the burial depth and basin geothermal gradient. (9) The discovered in many different types of deep petroliferous pressures of deep oil–gas reservoirs differ significantly, but basins, most have been discovered in low heat flux deep they typically vary with burial depth, genesis, and evolu- basins. (2) Many types of petroliferous traps are developed tion period. (10) Deep oil–gas reservoirs may exist with or in deep basins, and tight oil–gas reservoirs in deep basin without a cap, and those without a cap are typically of traps are arousing increasing attention. (3) Deep petroleum unconventional genesis. Over the past decade, six major normally has more natural gas than liquid oil, and the steps have been made in the understanding of deep natural gas ratio increases with the burial depth. (4) The hydrocarbon reservoir formation. (1) Deep petroleum in residual organic matter in deep source rocks reduces but petroliferous basins has multiple sources and many dif- the hydrocarbon expulsion rate and efficiency increase with ferent genetic mechanisms. (2) There are high-porosity, high-permeability reservoirs in deep basins, the formation of which is associated with tectonic events and subsurface X.-Q. Pang (&) Á W.-Y. Wang fluid movement. (3) Capillary pressure differences inside State Key Laboratory of Petroleum Resources and Prospecting, and outside the target reservoir are the principal driving Beijing 102249, China force of hydrocarbon enrichment in deep basins. (4) There e-mail: [email protected] are three dynamic boundaries for deep oil–gas reservoirs; a X.-Q. Pang Á W.-Y. Wang buoyancy-controlled threshold, hydrocarbon accumulation Basin and Reservoir Research Center, China University of limits, and the upper limit of hydrocarbon generation. (5) Petroleum, Beijing 102249, China The formation and distribution of deep hydrocarbon res- ervoirs are controlled by free, limited, and bound fluid C.-Z. Jia PetroChina Company Limited, Beijing 100011, China dynamic fields. And (6) tight conventional, tight deep, tight superimposed, and related reconstructed hydrocarbon res- C.-Z. Jia ervoirs formed in deep-limited fluid dynamic fields have Research Institute of Petroleum Exploration and Development, great resource potential and vast scope for exploration. Beijing 100083, China Compared with middle–shallow strata, the petroleum Edited by Jie Hao geology and accumulation in deep basins are more 123 2 Pet. Sci. (2015) 12:1–53 complex, which overlap the feature of basin evolution in the world, despite being faced with challenges and prob- different stages. We recommend that further study should lems today. The Former Soviet Union discovered four pay more attention to four aspects: (1) identification of 6,000 m or deeper industrial oil–gas reservoirs out of its 24 deep petroleum sources and evaluation of their relative petroliferous basins (Tuo 2002). The oil discovered in deep contributions; (2) preservation conditions and genetic basins in Mexico, the USA, and Italy contributes more than mechanisms of deep high-quality reservoirs with high 31 % of their present recoverable oil reserves (Kutcherov permeability and high porosity; (3) facies feature and et al. 2008) and the natural gas discovered there makes up transformation of deep petroleum and their potential dis- approximately 47 % of their total proved natural gas tribution; and (4) economic feasibility evaluation of deep reserves (Burruss 1993). China, too, has appreciable tight petroleum exploration and development. achievements in deep petroleum exploration. Compared with 2000, the deep reserves discovered in West China in Keywords Petroliferous basin Á Deep petroleum geology 2013 increased an average of 3.5 times. The ratio of deep features Á Hydrocarbon accumulation Á Petroleum petroleum reserves increased from 40 % in 2002 to 80 % exploration Á Petroleum resources in 2013. Of the 156 well intervals in the Tarim Basin that have been tested so far, 58 have gone deeper than 5,000 m. The deep drillhole success rate in the Jizhong Depression is 1 Introduction as high as 21.4 %. A 5,190-m-deep ‘‘Qianmiqiao buried hill hydrocarbon reservoir’’ was discovered in the Huang- As the world demands more petroleum and petroleum hua Depression (Tuo 2002). Despite these achievements, exploration continues, deep petroleum exploration has however, a lot of problems have also emerged in deep become an imperative trend. As it is nearly impractical to petroleum exploration. These include (a) the difficulty in expect any major breakthrough in middle or shallow basins understanding the conditions of deep oil–gas reservoirs and (Tuo 2002), petroleum exploration turning toward deep evolution due to the multiple tectonic events having taken basins has become inevitable. After half a century’s place in deep basins (Zhang et al. 2000; He et al. 2005), exploitation in major oilfields across the world, shallow (b) the difficulty in evaluating the resource potential and petroleum discoveries tend to be falling sharply (Simmons relative contribution due to the complex sources and evo- 2002). Nor are things optimistic in China, where the rate of lution processes of deep petroleum (Barker 1990; Mango increase of mid-and-shallow petroleum reserves is 1991; Domine´ et al. 1998; Zhao et al. 2001; Jin et al. 2002; increasingly slowing down (Wang et al. 2012). At the same Zhao et al. 2005; Darouich et al. 2006; Huang et al. 2012; time, the world’s petroleum consumption continues to Pang et al. 2014a), (c) the difficulty in predicting and increase. According to BP Statistical Review of World evaluating favorable targets due to the complex genesis and Energy 2014, from 2002 to 2012, the world’s petroleum distribution of deep, relatively high-porosity and high- consumption increase was virtually the same as its petro- permeability reservoirs (Surdam et al. 1984; Ezat 1997; leum output increase, with annual average oil and natural Dolbier 2001; Rossi et al. 2001; Moretti et al. 2002; Lin gas consumption increases of 1.35 % and 3.14 %, respec- et al. 2012), and (d) the difficulty in predicting and eval- tively, compared to the annual average output increases of uating the petroleum possibility in deposition targets due to 1.47 % and 3.23 %. In China, however, the petroleum the complex deposition mechanism and development pat- consumption increase is far greater than its output increase. tern of deep petroleum (Luo et al. 2003, 2007; Ma and Chu According to National Bureau of Statistic of China statis- 2008; Ma et al. 2008; Pang et al. 2008). All these problems tics in 2013, from 2000 to 2013, China’s average annual oil provide a tremendous challenge to deep petroleum and natural gas consumption increases were 6.1 % and exploration. 14.6 %, respectively, compared to the annual average With abundant resource bases and low proved rates, deep output increases of 1.93 % and 11.9 %. Deep petroleum, as petroliferous basins are important for further reserve and one of the strategic ‘‘three-new’’ fields for the global oil output increases (Tuo 2002;Zhaoetal.2005;Dai2006,Pang industry (Zou 2011) as well as one of the most important et al. 2007a; Zhu and Zhang 2009; Sun et al. 2010;Pangetal. development areas for China’s oil industry, forms the most 2014a). According to Dai (2006), the proved rate of the important strategically realistic area for China’s oil exploration concessions of PetroChina is 17.6 % for deep oil industry to lead future petroleum exploration and devel- and 9.6 % for deep natural gas, far lower than their mid-and- opment (Sun et al. 2013). All indicate that deep hydro- shallow counterparts of 39.6 % for oil and 14.6 % for natural carbon exploration is an inevitable choice toward ensuring gas. Pang et al. (2007a, b) suggest that West China contains energy supply and meeting market demands. around 45 % of the residual petroleum resources of China, and After half a century’s effort, gratifying achievements 80 % of these residual resources are buried in deep horizons have been made in deep petroleum exploration throughout more than 4,500 m below the surface, yet the present proved 123 Pet. Sci. (2015) 12:1–53 3 rate is less than 20 %. As such, implementing deep petroleum concept of deep basins does not only differ from scholar to resource research, tapping deep petroleum and increasing scholar, it also varies with the basin position and formation petroleum backup reserves are urgently needed if we ever characteristics. want to relieve the nation’s petroleum shortage and mitigate energy risks. Many scholars have investigated deep petroleum 2.3 Importance of using the same concept and criteria geologies and exploration (Perry 1997; Dyman et al.
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