大兴安岭东南部油气资源勘查区重磁异常初步解释  

Gravity and magnetic anomaly interpretation for oil and gas basins in Southeast Daxingan Mountains

作　　者：张明华[1] 乔计花[1] 田黔宁[2] 刘玲[3] 高飞[4] 孙中任[4] 

机构地区：[1]中国地质调查局发展研究中心,北京100037 [2]中国地质图书馆,北京100083 [3]北京勘察技术工程有限公司,北京100085 [4]中国地质调查局沈阳地质调查中心,辽宁沈阳110034

出　　处：《地质通报》2013年第8期1177-1184,共8页Geological Bulletin of China

基　　金：中国地质调查局项目(编号:1212010813073)

摘　　要：区域重磁异常的初步解释表明,西拉木伦河以北的松辽盆地外围地区存在诸多中、新生代盆地,发育3条NW向深大断裂和近NEE向的弧形构造。1∶20万重力异常显示,本区中、新生代盆地边界具有较明显的梯度异常特征,1∶5万航磁异常可较为清晰地勾画中新生代火成岩的分布。重、磁、电剖面联合反演揭示,中生代地层厚度1～4km,古生界规模宏大,厚度可达4～6km,是本区寻找油气的重要层位;古生界含油气盆地基底为志留系及更老地层;大兴安岭NE向展布的花岗岩具有蘑菇状侵入特征。通过重、磁异常联合反演,消除火成岩影响,得出突泉和扎鲁特地区的中生代基底深度1.5～4km,古生代的基底深度为2～6km。Regional gravity and magnetic anomaly interpretation shows that many Mesozoic sedimentary basins exist to the north of Xilamulun river in the west out-skater of Songliao basin,and there exists three NW directional deep faults and also some near NEE directional arc structures.Gravity data from 1∶200000 survey can generate clear gradient anomalies of the Mesozoic basin boundaries.Aeromagnetic data at the scale of 1：50000 can be used to outline the distribution of Mesozoic and Cenozoic igneous rock.Integrated gravity,magnetic and MT profile interpretation reveals that thickness of the Mesozoic in this region is from 1km to 4km,and that thickness of Paleozoic can be 4km to 6km.Later Paleozoic thus becomes an important layer for searching oil and gas in this region.Its basement is Silurian and earlier rocks.NE directional distributed garnits in Daxinganling mountain area are mushroom shaped intrusions.With eliminating the affection of igneous rocks in Tuquan and Zhalute basin areas,integrated gravity and magnetic modeling show that Mesozoic thickness variation is from 1.5km to 4km and thickness of the later Paleozoic varies from 2km to 6km.

关 键 词：大兴安岭东南部 油气盆地 重磁异常 联合反演 

分 类 号：TE121.1[石油与天然气工程—油气勘探] P631.1[天文地球—地质矿产勘探]