石油学报 ›› 2012, Vol. 33 ›› Issue (S2): 145-153.DOI: 10.7623/syxb2012S2014

• 地质勘探 • 上一篇    下一篇

多参数综合识别塔里木盆地下古生界白云岩成因

郑剑锋 1,2  沈安江 1,2  刘永福 3  陈永权 3   

  1. 1. 中国石油天然气集团公司碳酸盐岩储层重点实验室 浙江杭州 310023; 2. 中国石油杭州地质研究院 浙江杭州 310023; 3. 中国石油塔里木油田公司 新疆库尔勒 841000
  • 收稿日期:2012-06-08 修回日期:2012-10-15 出版日期:2012-12-25 发布日期:2013-03-01
  • 通讯作者: 郑剑锋。
  • 作者简介:郑剑锋,男,1977年7月生,2004年获长江大学硕士学位,现为中国石油杭州地质研究院高级工程师,主要从事碳酸盐岩沉积、储层研究。
  • 基金资助:

    国家重大科技专项(2008ZX05004-002)资助。

Multi-parameter comprehensive identification of the genesis of Lower Paleozoic dolomite in Tarim Basin, China

ZHENG Jianfeng 1, 2  SHEN Anjiang 1, 2  LIU Yongfu 3  CHEN Yongquan 3    

  • Received:2012-06-08 Revised:2012-10-15 Online:2012-12-25 Published:2013-03-01

摘要:

塔里木盆地下古生界广泛发育白云岩,其成因主要可以用萨布哈白云石化、渗透回流白云石化、埋藏白云石化和热液白云石化4种模式来解释。萨布哈白云岩发育于潮间-潮上坪蒸发环境,以含膏泥晶白云岩为特征;渗透回流白云岩发育于蒸发台地(或潟湖)环境,以保留原岩结构的粉晶白云岩为特征;埋藏白云岩发育于埋藏环境的各个阶段,以细-中晶白云岩为特征;热液白云岩以伴生热液矿物的中-粗晶白云岩为特征。不同成因类型的白云岩形成于不同的成岩环境和阶段,具有不同的岩石学、地球化学和地球物理响应特征。通过大量岩心、薄片和主量元素、碳氧同位素、锶同位素、稀土元素等地球化学数据的细致研究,再结合测井、地震响应特征、古地理、古气候、构造背景等资料,系统总结了塔里木盆地下古生界4种成因白云岩的多参数识别特征,通过综合分析能较好地克服成因多解性问题。

关键词: 多参数, 综合识别, 白云岩成因, 下古生界, 塔里木盆地

Abstract:

Massive dolomites are widely distributed in Lower Palaeozoic of Tarim Basin, northwest China. The genesis of these dolomites can be attributed to four dolomitization models, i.e., sabkha model, seepage-reflux model, burial model and hydrothermal model. The sabkha dolomites occurred in an evaporitic intertidal-supertidal environment and featured the deposits of gypsum-bearing dolomicrites. The seepage-reflux dolomites occurred in an evaporite platform(lagoon) environment and featured crystal powder dolomites with the original rock structure. The burial dolomites were developed in multi-stage burial environment, characterized by the fine-medium crystalline dolomites. The hydrothermal dolomites featured medium-coarse crystalline dolomites, which were associated with hydrothermal minerals. The dolomites that differed in the genesis were developed in various diagenetic environments and stages, showing different characteristics in terms of petrography, geochemistry and geophysical response. This study summarized the multi-parameter identification of four genesis models of Lower Palaeozoic dolomite in Tarim Basin based on the detailed study of massive cores, thin sections and geochemical data of major elements, carbon and oxygen isotopes, strontium isotopes and rare earth elements, in combination with comprehensive analysis of well logging, seismic response characteristics, paleogeography, paleoclimate and tectonic setting, etc. This methodology overcomes the multiple solutions of dolomite genesis by comprehensive analysis.

Key words: multi-parameter, comprehensive identification, dolomite genesis, Lower Palaeozoic, Tarim Basin