地质学报2013，Vol.87Issue(7)：1013-1020,8.
孟加拉湾若开褶皱带晚新生代构造特征初步研究
A Preliminary Study on the Late Cenozoic Structural Characteristics of the Arakan Fold Belt, Bay of Bengal
摘要
Abstract
Arakan fold belt (Bay of Bengal) located at the west piedmont of Indo-Burma Ranges consists of a series of NNW—SSE-trending anticlines,but its structural characteristics are very poorly studied.Integration of well data and 2D seismic reflection profiles was used to study the late Cenozoic structural characteristics of Arakan fold belt,with a focus on the characteristics of detachment levels and geometry and kinematics of anticlines.Arakan fold belt is characterized by multiple detachment levels:(1) basal detachment level,which situates at about 6.5 s (Two-way travel time); (2) intermediate detachment levels,which situates at the bottom of Quaternary or underlying upper Miocene at about 2.5 s.Those detachment levels generate two sets of detachment folds under regional compression.The basal detachments level controlled the development of Arakan fold belt,while the intermediate detachment level affected the deformation locally.The deformation time recorded by growth strata shows that the deformation of Arakan fold belt propagates from east to west with the leading edge formed in Quaternary.Based on structural analysis results we propose two end-member kinematic models for folding in Arakan fold belt.Model 1 without intermediate detachment level,detachment fold formed above basal detachment level; Model 2 with intermediate detachment level,two sets of detachment folds developed above basal and intermediate detachment levels,respectively.The wavelength of anticline in Model 2 is much shorter than that of Model 1,therefore,the wavelength of anticline can be used to judge whether intermediate detachment level developed or not in deformed strata pile.The geometry and kinematics of anticline is primarily controlled by underlying detachment level(s),the formation of overlapping anticlines or anticline bifurcation in Arakan fold belt would imply the underlying detachment level(s) changed along strike.Fluid overpressure could be an important deformation controlling factor in formation of Arakan fold belt.关键词
孟加拉湾/若开褶皱带/滑脱层/背斜几何学和运动学/滑脱褶皱Key words
Bay of Bengal/ Arakan fold belt/ multiple detachment levels/ geometry and kinematics of anticline/ detachment fold引用本文复制引用
唐鹏程,吕福亮,范国章,邵大力,王雪峰,孙辉,李丽..孟加拉湾若开褶皱带晚新生代构造特征初步研究[J].地质学报,2013,87(7):1013-1020,8.基金项目
本文为国家科技重大专项"海外重点风险项目勘探综合配套技术"(编号2011ZX05029)资助的成果. （编号2011ZX05029）
