摘要
综合地质对比法、声波时差法以及不连续镜质体反射率法得到西湖凹陷新生界T02 、T4 2 、T03三个重要的不整合面上地层的剥蚀厚度。剥蚀量的宏观分布与主要构造带的走向基本一致,局部构造的剥蚀与其特定的构造位置有关。T02 反射界面为斜坡-褶皱型地层剥蚀模式,剥蚀量主要分布在中央背斜构造带,沿龙井一井—东海一井—花港一井—玉泉二井—残雪一井一线附近的地层剥蚀量最大,可达2 0 0 0 m以上;西部斜坡区次之。T4 2 反射界面地层剥蚀模式为过渡型剥蚀模式,地层剥蚀量在凹陷东部边缘较大,最大可达80 0 m以上;中央背斜带的东海一井构造带、龙井一井构造带、花港一井构造带、玉泉一井构造带、玉泉二井构造带、残雪一井构造带、春晓构造带等有局部剥蚀,一般在4 0 0～6 0 0 m以内。T03反射界面为断块-斜坡地层剥蚀模式,地层剥蚀量以西部斜坡最大,中央背斜局部构造有剥蚀。西部斜坡带剥蚀量一般在2 0 0～80 0 m之间,中央构造带的龙井二井构造带、花港一井构造带、玉泉二井构造带、天外天一井构造带以及东缘构造带有较少剥蚀,一般在2 0 0～4 0 0 m以下。
The erosion amounts of T 2 0, T 4 2 and T 0 3, three major Cenozoic regional unconformities in the Xihu Depression of the East China Sea, have been calculated by a number of approaches such as comprehensive stratigraphical correlation of balanced cross sections, acoustic moveout and hiatus of Ro methods. The erosion amounts of the three surfaces are generally distributed along the major tectonic belts of the Xihu Depression and local erosions are distributed in certain tectonic locations. The erosion model of T 0 2 has been identified as the slope-fold type and the erosion amount is mainly distributed along the central tectonic belt. The maximum erosion amount,more than 2000 m, lies along Wells Longjing 1, East Sea 1, Huagang 1, Yuquan 2 and Canxue 1.The erosion model of T 4 2 has been identified as the interim type and the erosion amount is mainly distributed on the eastern edge of the Xihu Depression. The Maximum erosion amount is more than 800 m. Local erosion is along such tectonic belts as East Sea 1, Longjing 1, Huagang 1, Yuquan 1, Yuquan 2, Canxue 1 and Chunxiao, and the average amount is 400～600 m. The erosion model of T 0 3 has been identified as the type of fault block-slope and the erosion amount is mainly distributed on the western slope, ranging from 200 to 800 m, and the local erosion is in the central tectonic belt, which is along the Longjing 2, Huagang 1, Yuquan 2, Tianwaitian 1 and the eastern tectonic belts, the average amount of which is less than 200～400 m.
出处
《地质论评》
CAS
CSCD
北大核心
2005年第3期309-318,共10页
Geological Review
基金
中石化科技攻关项目 (编号 P0 0 0 16)资助的成果
