三门峡断陷盆地及邻区深部结构及成因——来自深地震反射与大地电磁测深的证据  

Deep structure and genesis of Sanmenxia fault basin and its adjacent area:Evidence from deep seismic reflection and magnetotelluric sounding

作　　者：何发岐 於文辉[2] 马超 张世晖[2] 黎小伟 刘德民[2] HE Faqi;YU Wenhui;MA Chao;ZHANG Shihui;LI Xiaowei;LIU Demin(SINOPEC North China Oil and Gas Branch Company,Zhengzhou,Henan 450006,China;China University of Geoscience(Wuhan),Wuhan,Hubei 430074,China)

机构地区：[1]中石化华北油气分公司,河南郑州450006 [2]中国地质大学(武汉),湖北武汉430074

出　　处：《地质学报》2024年第4期1088-1100,共13页Acta Geologica Sinica

基　　金：中石化项目(编号P22163,34550000-21-FW0399-0007,34550000-21-FW2099-0005)资助的成果。

摘　　要：近年来,围绕三门峡断陷盆地中的油气、地热资源做了大量的工作,成因机制研究较少,严重制约了矿产资源的勘探开发。本文在前人研究工作基础上,结合野外地质调查并利用高精度深反射地震剖面、大地电磁(MT)、重磁等地球物理探测技术,对三门峡盆地进行综合研究。发现三门峡盆地主要由东、西2个负花状构造构成,西花状构造体大于东花状构造体;盆地东部边缘以观音堂隆起与洛阳凹陷相邻,观音堂隆起发育有壳内透镜状低速体,其东、西两侧均发育有规模较大的隐伏逆断层。研究区内莫霍面为大约5 km厚度滑脱层,在深反射地震剖面上表现为蚯蚓状反射特征,指示滑脱层为西向运动。莫霍面滑脱层上部与下部新发现多条弧形断层。地质与地球物理资料综合研究表明,莫霍面滑脱层的解耦作用是三门峡断陷盆地花状构造形成的主因;在不同时空构造力系作用下,形成研究区新生代全地壳旋转花状构造盆地。In recent years,significant efforts have been dedicated to the study of oil,gas,and geothermal resources in the Sanmenxia faulted basin.However,the genetic mechanism behind these resources remains insufficiently investigated,posing a constraint on effective exploration and exploitation of mineral resources.On the basis of previous research,this study conducts a comprehensive investigation of the Sanmenxia basin,integrating field geological surveyswith advanced geophysical exploration technologies such ashigh-precision deep reflections seismic profiling,magnetotelluric(MT),gravity,and magnetic methods.The findings reveal that the Sanmenxia basin is mainly composed of two negative flower-like structures,with the western structure being larger than the eastern one.The eastern boundaryof the basin is adjacent to the Luoyang depression and the Guanyintang uplift.The Guanyintang uplift exhibitsa lens-like low-velocity body within itsshell,whilelarge-scale hidden reverse faults are prevalent on the east and west sides of the uplift.The Moho surface in the study area is characterized by a detachment layer,approximately 5 km thick,displaying distinctive earthworm reflection characteristics on the deep reflection seismic profile,indicative of westwardmovement.Notably,several newlyidentified arc-shaped faults are observed in the upper and lower parts of the Moho detachment layer.The comprehensive study of geological and geophysical data shows that the decoupling of the Moho detachment layer is the main reason for the formation of the flower structure in the Sanmenxia fault depression basin.The interaction of different temporal and spatial tectonic forceshas led to the development of a Cenozoic floral tectonic basin,characterized by whole-crust rotation in the study area.

关 键 词：三门峡断陷盆地 高精度深反射地震剖面 大地电磁 负花状构造 莫霍面滑脱层 弧形断层 

分 类 号：P631[天文地球—地质矿产勘探] P618.13[天文地球—地质学]