雪峰区(江口—洞口)深部地质构造初探

PRELIMINARY STUDY ON THE DEEP GEOLOGICAL STRUCTURE IN THE XUEFENG AREA(THE JIANGKOU—DONGKOU SECTION)

范小林 江兴歌 蒋洪堪 陆国新

Fan Xiaolin Jiang Xingge Jiang Hongkan Lu Guoxing

地质矿产部石油地质中心实验室, 无锡 214151

Central Lab of Petroleum Geology, MCMR

据雪峰地区陆壳地质反射测深结果,结合作者野外地质工作的认识,并参考MT地电断面结构,建立重力模型和进行人机交互对话联合解释,初步编制区内深部地壳构造的几何形态和介质分布状态的有关图件,据此得出:(1)区内存在元古代"漂移"微陆块(海山？)和古生代碰撞造陆作用下产生的构造岩浆(变质)岩脉群及中新生代陆内俯冲伴生壳下塑性(碎裂)地幔岩(块);(2)区内古生代"软敛合"和中新生代"陆壳的榨挤"两种不同动力体制下的形变共存;(3)深部-浅部系列冲断构造块体和不对称扇形构造形变体是组成区内"华南造山带"中一个重要的构造单元。

In accordance with the data of deep seismic sounding,MT sectional structure,gravitymodel of the continental crust in the Xuefeng Area,as well as the interactive comprehen-sive interpretation and understanding of the field observations in the area,a series of mapsconcerning about the geometry of deep crustal structures and median rocks are preliminari-ly compiled in this paper.It is concluded as:(1)The Proterozoic underplating"drifted"micro-continental blocks(or sea mounts),and tectonomagmatic(metamorphic)dikeswarms formed under Palaeozoic collision and epeirogeny,and ductile(or brittle)pyroliticmasses accompanied with the Meso-Cenozoic intracontinental subduction must be occurredin the area.(2)Both the Paleozoic"mildly sutured"structure and the Meso-Cenozoic"in-tra-crustal squeeze"which were dominated by two different dynamic systems must havetaken place.(3)A group of deep-shallow thrusting sheets and asymmetric deformationfan-tectosomes is a key tectonic(division)domain in S.China orogenic zone.

国家自然科学基金

https://doi.org/10.11781/sysydz199402128