【摘要】 东海西湖凹陷中南部是目前东海油气资源较为丰富的区域之一,海底工程地质调查是海洋油气田勘探开发工作中一项不可或缺的内容。过去数十年中,虽然海洋地质工作者为确保该区石油钻探平台安全就位和施工开展了大量井场调查工作,但多侧重于单个井场的海底不稳定因素(地质灾害)和平台桩基持力土层的物理力学特性调查和评价,对构成工程地质条件的基础,即海底工程地质地层的成因、层序特征和分布规律研究甚少。为此,根据浅地层剖面的层序地层学研究成果,以及区内的海洋地质和工程地质钻孔资料,对构成本区工程地质层的地震相特征、沉积环境条件、沉积相、沉积序列和各层序的物理力学特点作了分析研究,在此基础上综合确定划分出五套工程地质层,首次建立了该区域的工程地质层层序序列,并进行了土层编号。为后续的井场地质调查工作提供一些基础资料和技术研究思路。更多还原

【Abstract】 The Central South Area of Xihu Depression is an area with abundant petroleum resources in East China Sea.The pre-drilling engineering geology investigation(site investigation) is an indispensable part among offshore petroleum E&P,which is crucial for stability of drilling platforms’ foundation and safely of drilling process.Up to now,most of study is focused on individual drilling site.In individual drill site scale,the site’s seafloor instable factors(geohazards) and soil’s bearing capacity which affects platform foundation’s stability are studied.However,study on the forming mechanism,sequence,distribution characteristics of geotechnical strata on regional scale is scare.Understanding the regional geotechnical stratigraphy sequences of a specific area is crucial for following site investigation in this area.By stratigraphy sequences study using sub-bottom profiler data and study on regional marine geology and geotechnical drilling data,this paper analyzes the seismic facies,sedimentary environment,sedimentary facies,sedimentary sequences,and mechanical characteristics of Central South Area of Xihu Depression’s geotechnical strata.After integrated study, this area’s geotechnical strata are divided into five geotechnical sequences.This area’s overall geotechnical sequences are established for the first time,and the soil layers are numbered.The result can be used as guideline for the following site investigation in this area.更多还原