西非Rio Muni盆地深水水道特征与成因

现代地质 ›› 2015, Vol. 29 ›› Issue (1): 80-88.

西非Rio Muni盆地深水水道特征与成因

李磊¹, 闫瑞¹, 李宁涛¹,杨蕾²,张锦飞¹, 刘阳¹, 牛旭业¹, 孙宇锋¹

(1.西安石油大学地球科学与工程学院, 陕西西安710065;
2.中国石油华北油田公司地球物理勘探研究院, 河北任丘062552)

出版日期:2015-01-29 发布日期:2015-04-21
作者简介:李磊，男，博士，副教授，1979年出生，地质资源与地质工程专业，主要从事地震地质综合解释及海洋沉积方面研究。Email：lilei@xsyu.edu.cn。
基金资助:
国家自然科学基金项目(41302147，41372118)；全国大学生创新创业计划项目(201210705013)；西安石油大学2013年大学生科研训练计划项目。

Characteristics and Origin of Deep-water Channels in Rio Muni Basin, West Africa

LI Lei¹, YAN Rui¹, LI Ning-tao¹, YANG Lei², ZHANG Jin-fei¹, LIU Yang¹, NIU Xu-ye¹, SUN Yu-feng¹

(1.School of Earth Sciences and Engineering, Xi’an Shiyou University, Xi’an，Shaanxi 710065, China;
2.Geophysical Exploration Research Institute of PetroChina Huabei Oilfield Company, Renqiu, Hebei 062552,China)

Online:2015-01-29 Published:2015-04-21

摘要/Abstract

摘要：

深水水道沉积构型及其演化一直是沉积学界研究的热点。基于Rio Muni盆地深水区470 km²高分辨率三维地震数据，在精细地震解释的基础上，对研究区发育的深水水道的沉积构型、演化进行探讨。主要取得4点认识：(1)深水水道的弯曲度主要受控于物源供给和海底坡度，研究区发育弯曲水道、顺直水道2类深水水道；(2)起源于陆架边缘的深水水道，物源供给相对充分，弯曲度高，其剖面往往不对称，水道壁发育滑塌或阶地，垂向演化具有侧向迁移特征，发育废弃水道；(3)而起源于中上陆坡的深水水道，其弯曲度低，剖面具有U形特征，水道壁光滑无滑塌或阶地, 主要以垂向加积为主。由于物源供给不足，顺直水道逐渐被深海泥质披覆沉积充填；(4)同一条深水水道，由上陆坡向下陆坡，随着海底坡度的降低，其弯曲度呈增大趋势。

关键词: 弯曲水道, 顺直水道, 沉积构型, Rio Muni盆地

Abstract:

Study on the sedimentary architecture and evolution of deep-water channel is one of the most interesting fields in sedimentology. Based on high-resolution threedimensional seismic data sets which cover 470 km², the sedimentary architecture and evolution of submarine channels are discussed in deep-water Rio Muni basin. Four conclusions can be drawn in this paper: (1) The sinuosity of submarine channels are main dominated by the sediment supply and the seafloor gradient. Two main types of submarine channels: straight channels and sinuous channels have been recognized in the study area. (2) The high sinuosity submarine channel indents the shelf margin and is linked to areas of high coarse-grained sediment supply. Their mophologies often show asymmetrical cross-sections, terraces, slumped edges, lateral migration and abandoned channel. (3) The submarine channels heading on middle or upper continental slopes have a low sinuosity. Straight channels- morphologies commonly include a U-shaped cross-section, smooth walls lacking slumps or terraces, aggradational evolution. The straight channels with low sediment supply were draped by hemipelagic deposition. (4)The sinuosity of a submarine increases as the shelf gradient decreases.

Key words: sinuous channel, straight channel, sedimentary architecture, Rio Muni basin

中图分类号:

TE121.3

李磊, 闫瑞, 李宁涛,杨蕾,张锦飞, 刘阳, 牛旭业, 孙宇锋. 西非Rio Muni盆地深水水道特征与成因[J]. 现代地质, 2015, 29(1): 80-88.

LI Lei, YAN Rui, LI Ning-tao, YANG Lei, ZHANG Jin-fei, LIU Yang, NIU Xu-ye. Characteristics and Origin of Deep-water Channels in Rio Muni Basin, West Africa[J]. Geoscience, 2015, 29(1): 80-88.