西南石油大学学报(自然科学版)

• 地质勘探 • 上一篇    下一篇

川东北元坝地区长兴组生物礁沉积特征研究

邓剑1,段金宝1,王正和2,王明筏1   

  1. 1. 中国石化勘探南方分公司,四川成都610041
    2. 中国地质调查局成都地质调查中心,四川成都610081
  • 出版日期:2014-08-01 发布日期:2014-08-01

Research on the Reef Characteristic of Changxing Formation in Yuanba Area of Northeast Sichuan Province

Deng Jian1, Duan Jinbao1, Wang Zhenghe2, Wang Mingfa1   

  1. 1. Southern Exploration Company,SINOPEC,Chengdu,Sichuan 610041,China
    2. Chengdu Center of China Geological Survey,Chengdu,Sichuan 610081,China
  • Online:2014-08-01 Published:2014-08-01

摘要:

普光气田的发现启示着石油工作者把勘探目光转向了同样位于开江—梁平陆棚边缘的元坝地区。经过新一轮勘探,发现元坝地区长兴组生物礁具有很大勘探潜力。基于地震、钻井及岩芯资料的综合分析,对川东北元坝地区长兴组生物礁沉积特征进行了精细研究。研究表明,元坝地区长兴组生物礁主要发育于长二段,且不同沉积环境及不同部位控制了生物礁生长发育特征的差异,具体表现为:西部广海边缘生物礁比东部广海边缘及潮道边缘生物礁更发育,规模更大,且建隆特征十分明显;广海边缘因水动力强,营养物更加丰富,因此多发育以抗浪结构为主的骨架礁;而潮道边缘因水动力相对较弱,营养物相对贫乏,多发育障积礁;长兴晚期,元坝西部地势的隆升导致其沉积环境更加有利于生物礁的发育,从而表现为生物礁优势生长区自东向西迁移的特征。

关键词: 川东北, 元坝地区, 长兴组, 生物礁, 沉积特征

Abstract:

The discovery of Puguang Gas Field inspired explorers to turn to Yuanba Area,which is also a part of Kaijiang– Liangping shelf edge. The new exploration indicates the great exploration potential with Changxing Formation in Yuanba Area. Based on the comprehensive analysis of seismic,drilling and core data,we made detailed researches on the reef depositional characteristics of Changxing Formations in northeastern Sichuan. The results show that the reefs are mainly developed in the 2nd member of Changxing Formation,and the different sedimentary environments control characteristics of reefs′ growth and development. The reefs closed to the edge of the western wide sea are better developed than the reefs closed to the edge of the eastern wide sea and the tidal channel edge,and they have a larger scale,and theirs buildups characteristics are very prominent. In the area of wide sea edge,because of the stronger hydrodynamic and the richer nutrient,the skeleton reefs are usually developed and they usually have anti-wave structures. But in the area of tidal channel edge,because of the relatively weaker hydrodynamic and the lack of nutrients,the bafflereefs are usually developed. At the late Changxing stage,in the western Yuanba Area,the depositional environment is fit for the development of the reefs because of the terrain uplift. So the favorable growing area of reef is characteristic of migration from east to west.

Key words: northeastern Sichuan, Yuanba Area, Changxing Formation, reef, depositional characteristics