基于航空重磁特征对突泉盆地构造的认识

Recognition of Tuquan Basin structure based airborne gravity magnetic characteristics

为获取突泉盆地航空物探基础地质资料,为油气调查评价提供参考,中国国土资源航空物探遥感中心在该盆地开展了1∶10万航空重磁综合调查工作。利用最新的航空重磁资料及实测岩石物性数据,对突泉盆地及其邻区重磁异常特征进行研究,分析航空重磁异常与地层展布、断裂活动、岩浆岩体的分布关系,重点探讨盆地的基底性质。结果表明,研究区航空重力异常与航磁异常在强度、范围、形态、梯度和走向等方面具有一定的规律性,该区断裂体系分布与重磁场特征明显相关,NNE-NE向、NW向及NE向3组断裂明显控制盆地沉积岩体及岩浆岩体的展布,盆地基底由下古生界浅变质岩系和前古生界中等变质岩系构成。

In order to obtain the basic data of aerogeophysical survey and provide some reference for hydrocar nresources survey and evaluation in Tuquan Basin, China Aero Geophysical Surey and Land and Resources carried out the 1： 100 000 airborne gravity and magnetic survey in this area Based on the latest airl） me gravity and magnetic data and measured petrophysical data, the authnetic anomaly characteristics of Tuquan Basin and its adjacent areas, analyzed the relationshgravity and magnetic anomalies and stratigraphic distribution, faults movement and igneous rockmainly discussed the characteristics of basin basement. The results show that the airborne anomalies of the study area have obvious regularity in the intensity, distribution range, shape, gradient andstrike. The distrilDution of fault system in this area has obvious correlation witli gravity and magnetic field charac-teristics. The NNE - NE trending, NW trending and NE trending of fault structures have obvious controlling effects on the basin sedimentary and igneous rocks distribution. The basin basement should be composed of low- grade metamorjDhic rocks of Lower Paleozoic and moderately metamorjDhic rocks of Prepaleozoic.