沉积学报2025，Vol.43Issue(1)：99-107,9.DOI:10.14027/j.issn.1000-0550.2022.141
西非海岸盆地海底麻坑沉积特征研究
Sedimentary Characteristics of Seabed Pockmarks from West Africa:A case study in an oilfield at the deep-water region in the Niger Delta front
摘要
Abstract
[Objective]Seabed pockmarks are not only active records and instructions of the seabed fluid but also key factors affecting oilfield and offshore platforms.Therefore,their study is extremely important.The Niger Delta Ba-sin is extremely rich in deep-water oil and gas reserves and is an important oil and gas production area globally.There-fore,studies of their seabed pockmark characteristics have particular value.[Methods]Based on sedimentary princi-ples and methods and high resolution three-dimensional(3D)seismic data conducted on the sedimentary characteris-tics,genetic mechanism,and research significance of seabed pockmarks near West Africa,we identified and illus-trated the sedimentary characteristics and size and genetic mechanism of seabed pockmarks in the study areas,ex-ploring their significance.[Results](1)Based on the plane morphological characteristics of pockmarks,there are mainly two types of pockmarks in the study area:striped pockmarks and isolated pockmarks,which are circular,elliptical and crescent in shape on the plane.The length of the striped pockmarks is 0.5-3.0 km,the width is 0.5-1.0 km,and the width of the isolated pockmarks is generally 10-300 m;(2)According to the development characte-ristics and sedimentary characteristics,Pockmark distribution characteristics of pockmark were found to be isolated and banded in the study area,and the genesis of pockmarks is classified into five types:dip structure,fault,mud volcano,ancient channel,and sedimentary boundary.The profile is U-shaped or W-shaped,and the seismic reflec-tion is disordered;(3)They are primarily caused by plastic fluid and oil and gas leakage.One is caused by plastic fluid,the other is caused by oil and gas spilling along the fault.The high pressure fluid is squeezed into the overlying sedimentary layer along the fault plane,and the reduction of local stress causes the submarine surface sediment to un-dergo plastic deformation,forming an upward migration channel.The finally liquefied sediment is transported by the underflow,forming a pockmark.[Conclusions]The results of pockmark can indicate the best locations for oil and gas exploration and development,including drilling and engineering facilities in the future,we should be paid atten-tion to exploration and development In the process oil and gas of field.关键词
海底麻坑/沉积特征/成因机制/西非/深海海底Key words
seabed pockmark/sedimentary characteristics/genetic mechanism/West Africa/deep sea floor分类
地质学引用本文复制引用
陈飞,蔡文涛,范洪军,梁旭,王海峰..西非海岸盆地海底麻坑沉积特征研究[J].沉积学报,2025,43(1):99-107,9.基金项目
国家科技重大专项(2011ZX05030005)[National Science and Technology Major Project,No.2011ZX05030005] （2011ZX05030005）
