宁芜北部南门头地区深部找矿地质—地球物理综合研究

摘要

During the period of 2007～2015,lots of geological and geophysical survey work was carried out in Nanmentou area located in the north of Ningwu basin.On such a basis,researchers provided experience and advice for guiding deep ore prospecting in Yangtze Region.There are multiple solutions of geophysical data interpretation in the process of research.In the project implementation process,some drill holes which were designed according to the comprehensive anomalies (especially the geophysical anomalies) produced prominent effects,but some failed to show satisfactory results.The work to sum up the experience of failure and success of the arrangement of drilling is very important.On the basis of analyzing the petrophysical data of different lithologies in this area,the gravity and magnetic data were processed and interpreted,the factors causing gravity and magnetic anomalies were summarized,and a new view for distinguishing rock masses,volcanic rocks,exploration breccia pipes,volcanic channels and the distribution of fractures in this area was set up.In this paper,according to the characteristics of the CR and CSAMT electrical profiles,gravity and magnetic anomalies,as well as drill hole curves (physical and logging),the authors summed up geophysical anomalies,and the results have reinforced the understanding of the deep geological structures in this area and enriched the geophysical anomaly interpretation experience.Through the study of second time interpretation of electrical prospecting and gravity and magnetic anomalies and a comprehensive analysis of the previous data,the experience in geophysical interpretation has been enriched,which may have some directive significance for the application of exploration technology to the prospecting for deep deposits in Yangtze Region.%南京地质调查中心于2007 ～ 2015年间在宁芜北部南门头地区开展了大量的物探测量和地质工作,为长江中下游深部找矿提供了找矿经验和方法指导.南门头地区物探资料的解释存在一定多解性,在分析物性数据的基础上,对南门头地区的重磁异常数据进行了一定的处理和解释,总结了引起重力异常的主要因素,并对本区岩体、火山岩、隐爆角砾岩筒、古火山通道的分布及断裂特征有了新的认识.在验证钻孔的控制下,结合重磁剖面、CR法与CSAMT法剖面特征、钻孔测井曲线特征,对本区深部地质结构有了整体的认识.通过对电法、重磁异常的二次解释及对以往取得的资料进行的综合分析,丰富了物探异常解释的经验,对于长江中下游深部找矿方法技术的研究及应用具有一定的指导意义.