沉积盆地异常低压的成因

张立宽; 王震亮; 于在平

doi:10.11781/sysydz200405422

沉积盆地异常低压的成因

doi: 10.11781/sysydz200405422

西北大学, 地质学系, 陕西, 西安, 710069

基金项目: 国家重点基础研究发展规划(天然气"973")项目(2001CB209103).

详细信息

作者简介:
张立宽(1979- ),男(汉族),辽宁开原人,硕士研究生,主要研究方向为油气田地质学.

中图分类号: TE121.3
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出版历程
- 收稿日期: 2004-05-26
- 修回日期: 2004-08-02
- 刊出日期: 2004-09-25

CAUSES OF SUBNORMAL PRESSURE IN THE SEDIMENTARY BASINS

Department of Geology, Northwest University, Xi'an, Shaanxi 710069, China

摘要

摘要: 将异常低压的形成机制归纳为4大类:1)构造抬升和地层剥蚀、孔隙水化学作用引起的孔隙体积增大;2)封闭层压力的释放、物性差异引起的非均匀流、渗析作用和轻烃扩散作用等流体排出造成的压力降低;3)饱和天然气藏的深埋;4)承压面低于地表。分析了每一类成因机制对形成异常低压的贡献大小。其中,构造抬升引起一定程度的孔隙回弹和温度降低,从而导致地层压力下降,是构造抬升强烈的沉积盆地中形成异常低压的主要原因。而在抬升幅度较小的地区,低压的形成则常与轻烃扩散和饱和天然气藏的深埋有关。孔隙水的化学作用和渗析作用受自身因素的制约,对异常低压贡献不大。除物性差异引起的非均匀流外,其它的低压形成机制都需要以好的封闭条件为前提,否则地层压力将衰减至常压。在中国西部盆地,因地形起伏较大,承压面低于地表,使得地层压力偏低,但并非真正意义上的低压,只是由于表达方式(起算深度是否等于地表)的原因而造成。
- 成因 /
- 异常低压 /
- 封闭 /
- 沉积盆地
Abstract: The forming mechanisms of subnormal pressure can be divided into 4 types: 1)increase in pore volume caused by tectonic uplift and formation erosion, or chemical effects of pore water; 2)fluid flowing out due to the release of overpressure in seal formation, unhomogeneous flow, osmosis across semipermeable shale membranes and diffusion of light hydrocarbon; 3)deep burial of saturated gas reservoir; 4)piezometric surface lower than ground surface. In some sedimentary basins in which large-scale tectonic uplift has taken place, the main cause of low pressure may be the removal of overburden, which results in dilation of pore volume with the consequent reduction in stress and temperature. Subnormal pressure in the small-scale uplift area is mostly related to the diffusion of light hydrocarbon and the burial of saturated gas reservoir. The release of overpressure seems to be a probable mechanism; however, it is a question how low pressure can be preserved. The chemical effect and osmosis effect of pore water are self-limited, which may not be the major factors in subnormal pressure system. Aside from unhomogeneous flow, other mechanisms require good seal, otherwise pressure will be equalized to normal hydrostatic. The low pressure is not a true meaning subnormal pressure, because that the piezometric surface is lower than the ground surface, but people give a wrong assumption in the course of showing the relative size of pressure.
- causes of generation /
- subnormal pressure /
- seal /
- sedimentary basin

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参考文献(25)

[1]	曲江秀,查明.准噶尔盆地异常压力类型及成因探讨[J].石油实验地质,2003,25(4):333～336
[2]	黄志龙,姜亮.东海盆地丽水凹陷异常压力系统特征[J].石油实验地质,2002,24(1):52～57
[3]	李延钧,陈义才,黄键全等.吐哈盆地红南-红西地区油气负压系统的成因[J].西南石油学院学报,1999,21(1):6～9
[4]	华保钦,林锡祥,杨小梅等.鄂尔多斯盆地下古生界负压气藏及运移[J].沉积学报,1994,11(2):105～113
[5]	楼章华,高瑞祺,蔡希源等.流体动力场演化与地层流体低压成因[J].石油学报,1999,20(6):27～31
[6]	曾治平,蔡勋育,邹华耀.负压地层形成机制及其对油气藏的影响[J].地球学报,2002,23(3):255～258
[7]	刘晓峰,谢习农.东营凹陷低压系统的特征及成因机制[J].石油与天然气地质,2002,23(1):66～70
[8]	杜栩,郑洪印.异常压力与油气分布[J].地学前缘,1995,4(2):137～147
[9]	夏新宇,曾凡刚,宋岩.构造抬升是异常高压的成因吗?[J].石油实验地质,2002,24(6):496～501
[10]	夏新宇,宋岩.沉降及抬升过程中温度对流体压力的影响[J].石油勘探与开发,2001,28(3):8～11
[11]	夏新宇,宋岩.构造抬升对地层压力的影响及克拉2气田异常压力原因[J].天然气工业,2001,21(1):30～34
[12]	Warbrick R E, Osborne M J. Mechanisms that generate abnormal pressure: an overview[A]. In: Law B E, Ulmishek G F, Slavin V I, eds. Abnormal Pressure in Hydrocarbon Environments: AAPG Memoir[C]. Tulsa: AAPG,1998.13～43
[13]	Russell W L. Pressure-depth relation in Appalachian Region[J]. AAPG Bulletin,1972,56(3): 528～536
[14]	Prake A D, Wayne C. Oil and gas in reservoirs with subnormal pressure[J]. AAPG Bulletin,1977,61(12): 2 134～2 142
[15]	Bradley J S. Abnormal formation pressure[J]. AAPG Bulletin,1975,59(6):957～973
[16]	Hodgman C D. Handbook of chemistry and physics[M]. Cleveland, Ohio: Chemical Rubber Pub Co,1957.3 213
[17]	邱隆伟,姜在兴,操应长等.泌阳凹陷碱性成岩作用及其对储层的影响[J].中国科学,2001,31(9):752～759
[18]	王宏语,康西栋,李军等.松辽盆地徐家围子地区深层异常压力分布及其成因[J].吉林大学学报(地球科学版),2002,32(1):39～43
[19]	Zhou G J. Origin of subpressure and hydrocarbon exploration in Shiwu fault depression, Songliao Basin, China[J]. AAPG Bu-lletin,1994,78(8):1 336
[20]	刘文龙,李思田,孙德君等.松辽盆地深层孔隙流体压力预测[J].地球科学,2000,25(2):137～142
[21]	Kenneth B, John D. Hydrodynamics of Denver basin: explanation of subnormal fluid pressure[J]. AAPG Bulletin, 1988, 72(11):1 334～1 359
[22]	Hubbert M K.Entrapment of petroleum under hydrodynamic condition[J]. AAPG Bulletin, 1953, 37(8): 1 954～2 026
[23]	李明诚.石油与天然气运移[M].北京:石油工业出版社,1994.59～60
[24]	Young A, Low P F. Osmosis in argillaceous rocks[J]. AAPG Bulletin, 1965, 49(7):1 004～1 007
[25]	Barker C. Generation of anomalous internal pressures in source rocks[A]. In: IFP, ed. Migration of Hydrocarbon in Sediment-ary Basin[C]. 2nd IFP Explor Res Conf, Carcans, Paris, 1987. Paris: IFP,1987.79～112