Microscopic occurrence of oil in tight sandstones and its relation with oil sources - A case study from the Upper Triassic Yanchang Formation, Ordos Basin

被引：0

作者：

机构：

[1] Research Institute of Petroleum Exploration and Development, PetroChina Changqing Oilfield Company, Xi'an

[2] National Engineering Laboratory of Exploration and Development of Low Permeability Oil-Gas Fields, Xi'an

[3] Department of Reservoir Evaluation, PetroChina Changqing Oilfield Company, Xi'an

来源：

Niu, X. (nxb_cq@petrochina.com.cn) | 1600年 / Use me卷 / 34期

关键词：

Low permeability reservoir; Multi-scale pore; microscopic occurrence; Nuclear Magnetic Resonance; Ordos Basin; Tight oil;

D O I：

10.11743/ogg20130302

中图分类号：

学科分类号：

摘要：

Identifying pore distribution of tight reservoirs and the microscopic occurrence of oil in pores of different scales is critical to understand the characteristics of tight oil. In this study, tight sandstone samples from Yanchang Formation, Ordos Basin, were investigated through Nuclear Magnetic Resonance (NMR) experiment. Nano-scale pores are common in the tight sand of Yanchang Fm and macro-scale, medium-scale, small-scale, micro-scale and nano-scale pores co-exist in the samples. The microscopic occurrence of oil in multiple-scale pores are compared between near-source reservoir and far-source reservoir. In near-source reservoirs, oil exists in all kinds of pores and the micro-pores and nano-pores are saturated with oil. In contrast, in far-source reservoirs, oil selectively occur in macro-scale and medium-scale pores and nano-pores contains no oil. The abnormal pressure caused by hydrocarbon-generation in Chang 7 layer is believed to be the main controlling factor for different occurrences of oil in multi-scale pores in tight reservoir. This provides a theoretical basis for understanding the distribution of tight oil reservoir. It is concluded that the upper Chang 8, the Chang 7 and lower Chang 6 reservoirs within the distribution area of Chang 7 source rock are the main potential targets for tight oil exploration in the future.

引用

页码：288 / 293

页数：5

共 34 条

[1]

Zou C., Zhu R., Bai B., Et al., First discovery of nano-pore throat in oil and gas reservoir in China and its scientific value, Acta Petrologica Sinica, 27, 6, pp. 1857-1864, (2011)

[2]

Liao Q., Hu H., Lin J., Et al., Petroleum exploration prospect of the Jurassic tight reservoirs in central Sichuan Basin, Oil & Gas Geology, 32, 6, pp. 815-822, (2011)

[3]

Yang Q., Nie M., Song F., Threshold pressure gradient of low permeability sandstone, Journal of Tsinghua University(Natural Science Edition), 44, 12, pp. 1650-1652, (2004)

[4]

Huang Y., Research on Percolation Mechanism of Low Permeability Reservoir, pp. 1-160, (1998)

[5]

Zhu Z., Zeng J., Wu H., Et al., An experimental study on oil migration and accumulation in low-permeability sandstone, Oil and Gas Geology, 28, 2, pp. 229-234, (2007)

[6]

Xion W., Lei Q., Liu X., Et al., Pseudo threshold pressure gradient to flow for low permeability reservoirs, Petroleum Exploration and Development, 36, 2, pp. 232-236, (2009)

[7]

Zou C., Yang Z., Tao S., Et al., Nano-hydrocarbon and the accumulation in coexisting source and reservoir, Petroleum Exploration and Development, 39, 1, pp. 12-25, (2012)

[8]

Yang H., Zhang W., Leading effect of the seventh member high-quality source rock of Yanchang Formation in Ordos basin during the enrichment of low-penetrating oil-gas accumulation-geology and geochemistry, Geochemica, 37, 1, pp. 59-64, (2005)

[9]

Zhang W., Yang H., Li J., Et al., Leading effect of the seventh member high-quality source rock of Yanchang Formation in Ordos basin during the enrichment of low-penetrating oil-gas accumulation-hydrocarbon generation and expulsion mechanism, Petroleum Exploration and Development, 33, 3, pp. 289-293, (2006)

[10]

Zhao W., Hu S., Wang Z., Et al., Key role of basement fault control on oil accumulation of Yanchang Formation, Upper Triassic, Ordos Basin, Petroleum Exploration and Development, 30, 5, pp. 1-5, (2003)

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