干旱气候变化与可持续发展

深部物质运动的气体地球化学特征

展开
  • 中国科学院兰州地质研究所气体地球化学国家重点实验室  730000
杜建国

收稿日期: 1993-12-08

  修回日期: 1994-01-10

  网络出版日期: 1994-05-01

MANTLE DEGASSING—A GASGEOCHEMICAL FEATURE OF DEEP-EARTH-MATTER MOVEMENT

Expand

  • State Key Lab. of Gasgeochemistry, Lanzhou Institute of Geology,Chinese Academy of Sciences, Lanzhou  730000

Received date: 1993-12-08

  Revised date: 1994-01-10

  Online published: 1994-05-01

摘要

根据氦同位素地球化学资料讨论了中国东部和云南腾冲地区上地幔的脱气。尽管地球脱气作用主要发生在地球形成时的十亿年间,但是后期的脱气作用仍是影响大气圈演化的主要因素。在两种力学性质不同的构造带──中国东部大陆裂谷和位于欧亚板块与印度板块缝合带的腾冲火山区,采集了天然气样,并分析了气体组分和氦同位素组成,较高的3He/4He值和地质、地球物理资料表明天然气和温泉气中的氦相当一部分是来自上地幔。来自上地幔的氦和其他气体自第三纪以来不断在气藏中聚集或向大气中逃逸。伴有源于上地幔的岩浆活动的地幔脱气是深部物质运动的具体表现形式,它对新生代气候演变可能有直接影响。

本文引用格式

杜建国,王先彬,谢鸿森 . 深部物质运动的气体地球化学特征[J]. 地球科学进展, 1994 , 9(3) : 48 -52 . DOI: 10.11867/j.issn.1001-8166.1994.03.0048

Abstract

The paper discusses upper-mantle degassing in East China and Tengchun district of Southwestern China based upon data of helium-isotope geochemistry. Even though earth degassing mainly occurred in beginning 1000 Ma of the Earth history, mantle degassing is an important factor affecting atmosphere evolution since then. Mantle degassing is one of manisfestations of deep-earth-matter movement. Gas samples were collected from production gas-oil wells and hot springs. The gas-oil wells distribute in continental rift valley. East China,and the hot springs occur in Tengchun volcanic district where belongs to the collision zone between the Eurasia plate and India plate. Molecular component and helium isotope composition were analyzed 3He/4He ratios of natural gas have arrange of 0.2 Ra to 5.2 Ra (Ra stands for 3He/4He ratio of atmosphere). 3He/4He ratios of the hot springs are from 0.5 Rato to 5.1 Ra. Higher values of helium isotope composition and geological and geophysical data indicate that helium in the natural gases and hot-spring gas is partially derived from upper mantle.It can be considered that helium migrating from upper mantle have being accumulated in gas reservoir or escaped to atmosphere since Paleocene Epoch according to the time of gas reservoir formation and Quaternary volcanicity in Tengchun district. Larger 3He/4He ratios have a close relation to magmatite originated from upper mantle. It can be concluded, therefor, that upper in continental rift valley East China and Tengchun volcanic district is in a stage of stronger degassing in Cenozoic Era.Upper mantle degassing may be one of the most important factors affecting Cenozoic evolution of atmosphere and environment.

参考文献

[1] 谢鸿森,侯渭.张福勤译.地球物质研究.西北大学出版社,1991.
[2] 王先彬.稀有气体同位素地球化学和宇宙化学.科学出版社,1989.
[3] Schwartzman D W. In: E C Alexander Jr and M Ozima Ed. Adva Earth Plant Sci Japan Scientific Societies Press, 1978,185-191.
[4] Hart R and Hogan L. In: E C Alexander Jr and M Ozima ed. Adva Earth Plant Sei Japan Scientific Societies Press,1978,192-206.
[5] 陈家振,高其斋,毛继国译.地球裂谷带.地震出版社,1982.
[6] 马杏垣,宿俭.现代地壳运动研究(1).地震出版社,1985,5-6.
[7] 邓晋福,赵海玲.中国上地慢特征与动力学论文集.地震出版社,1990,8-13.
[8] 丁国瑜主编.中国岩石圈动力学概论.科学出版社,1991.
[9] 魏斯高等.中国东部大陆边缘地带的岩石圈结构与动力学.科学出版社,1990.
[10] 国家地震局《深部物探成果》编写组.中国地壳上地幔地球物理探测成果.地震出版社,1986.
[11] Mamyrin B A and Tolstikhin L N. Helium Isotopes in Nature.Elsevier Sci Publ B V,1984.
[12] 杜建国.轻稀有气体地球化学.地质地球化学,1989,(4):56-59.
[13] 徐永昌.慢源氦的工业储聚与郯庐断裂带.中国科学(B),1993,33:1495-1503.
[14] Du J G.3He/4He rations and heat flow in the continental rift vally, Eastern China.Chinese J Geochem, 1992, 11(3):237-243.
[15] 杜建国等.非烃气体地球化学.徐永昌等著.天然气形成机理及应用.科学出版社,1994,第12章.
[16] 王先彬等.腾冲火山区温泉气体组分和氦同位素组成特征.科学通报,1993,39(9):814-817.

文章导航

/