摘要
柴达木盆地北缘地处秦祁昆成矿域西段,成矿成藏条件优越,但油气成藏特征及油气分布受构造控制明显且构造体系复杂,前人通过地球物理勘探手段对该地区油气成藏主控因素的研究较为薄弱。结合以往柴北缘德令哈地区小比例尺的布格重力异常分布特征和该区域地质环境、基底岩性、起伏形态及构造特征分析,本研究实测的1∶25万数据填补了该区小比例尺面积性重力数据的空白,同时进行了重力异常的精细化新提取和反演解释。将柴北缘地区分为宗务隆山裂谷、欧龙布鲁克构造带、诺木洪盆地3个构造单元,并将欧龙布鲁克构造带进一步细分为德令哈凹陷、欧龙布鲁克断隆、欧龙布鲁克南缘裂谷、滩间山蛇绿混杂岩带4个次级构造单元,分别与本研究划分的重力北部高值区、中部高、低过渡区及南部低值区相对应。研究表明,柴北缘德令哈地区现今的重力异常特征能够反映基底构造。
The northern margin of Qaidam Basin is located in western part of the Qinling-Qilian-Kunlun oreforming domain with favorable conditions for mineralization,The formation characteristics and distribution of hydrocarbons are obviously controlled by the tectonic system and are complex.Previous studies on the main controlling factors of oil and gas accumulation in this area through geophysical exploration methods are relatively weak.Combined with previous distribution characteristics of the bourg gravity anomaly at small scale in northern margin of the Qaidam Basin and the analysis of the geological environment,basement lithology,undulating morphology and tectonic characteristics of the region.The 1∶250,000 data measured in this study fills the gap of large scale area-based gravity data in the region.and the refined new extraction and inversion interpretation of the gravity anomaly were carried out at the same time.The northern margin of Qaidam Basin is divided into three tectonic units:Zongwulong Mountain Rift,Oulongbuluk Structural Belt,and Nomuhong Basin.The Oulongbuluke tectonic belt is further subdivided into four secondary tectonic units:Delingha sag,Oulongbuluke fault uplift,Oronbrook south rim rift and Tanjianshan ophiolitic melange belt.which correspond to the gravity northern high value region,the central high-low transition area,and the southern low value area of gravity respectively.The research shows that the current gravity anomalies in Delingha area in northern margin of the Qaidam Basin can reflect the basement structure.The author hopes that this study will play a corresponding guiding role in the follow-up research on deep structural analysis,mineralization,and oil and gas resource prediction in this area.
作者
吴晓飞
李世斌
雷清
林星
马为
WU Xiaofei;LI Shibin;LEI Qing;LIN Xing;MA Wei(Tianjin Huakan Geophysical Exploration Center,Tianjin 300170,China)
出处
《矿产勘查》
2023年第7期1141-1151,共11页
Mineral Exploration
基金
中国地质调查局项目“青海1∶25万盐池湾幅、德令哈镇幅、诺木洪幅基础地质调查修测”(KJ2021-15)资助。
关键词
柴北缘
德令哈
断裂构造
构造单元
重力场特征
northern margin of the Qaidam Basin
Delingha
fault
tectonic unit
gravity field characteristics
