四川盆地北部米仓山冲断带多层滑脱系统构造分析  

Analysis of the Multi-Detachment Structure in Micangshan Thrust Belt,Northern Sichuan Basin

作　　者：文竹[1] 何登发[1] 樊春[1] 孟征[2] 

机构地区：[1]中国地质大学能源学院,北京100083 [2]中国石油勘探开发研究院南美研究所,北京100083

出　　处：《新疆石油地质》2013年第3期282-286,共5页Xinjiang Petroleum Geology

基　　金：国家自然科学基金(40739906)

摘　　要：根据野外地质、地震地质资料及平衡复原技术对米仓山山前二维构造特征进行解析,通过三维可视化分析对米仓山山前各断层的空间组合方式进行研究。结果表明,米仓山山前构造特征具有分层性:深部构造由震旦系滑脱层控制,发育基底逆冲断层;中部构造由震旦系与三叠系嘉陵江组滑脱层共同控制,具双重构造;浅层构造受三叠系嘉陵江组滑脱层影响,呈单斜构造。由于三叠系嘉陵江组顶部滑脱层向东逐渐抬升,导致了米仓山山前由西向东缩短率逐渐减小,中部双重构造中的断层主要呈5种组合特征:断层上发育次一级的调节断层,断层间彼此保持平行向两侧延展,断层与断层发生相交,断层逐渐向上抬升最终消亡,断层内部产生新的调节断层。Micangshan mountain located in the southem margin of Qinling orogenic belt was subject to squeezing action from north to south since the Indosinian, thus developing multiple sets of detachment structures that led to complex deformation features in the piedmont of Mi- cangshan mountain. By means of field geologic sections, seismogeology profiles and balance recover, this paper analyzes the 2D structural characteristics of it, researches the spatial assemblage patterns of faults of 3D visualization in it. The result shows that the structures in the piedmont are of stratification： the deep structure was controlled by Sinian det~/chment zone, developing basement thrust fault; the middle structure was controlled by both Sinian and Triassic Jialingjiang detachment zones, and the shallow structure appeared a monocline con- trolled by the Jialingjiang detachment zone. The eastward gradual upraising of the top detachment zone of Jialingjiang formation resulted in decrease of shortening rate from west to east of the piedmont of Mieangshan mountain. There exist five patterns of dual-structural fault com- binations in the middle detachment zone： the secondary accommodate fault; a fault keeping parallel with other one and extending toward the two sides of it; a fault intersecting with other one; fault upraising gradually and subduction; generating new accommodate faults within original faults.

关 键 词：米仓山 滑脱层 断层相关褶皱理论 平衡复原 三维可视化 

分 类 号：TE111.2[石油与天然气工程—油气勘探]