| 河北省深部地质构造特征与区域成矿规律相互关系的初步研究 |
| 点此下载全文 |
| 引用本文：.1982.A preliminary study of the deep tectonic pattern in Hebei Province and its relations with regional mineralizations[J].Mineral Deposits,1(1):69~82 |
| Hits: 2420 |
| Download times: 2231 |
|
| |
| A preliminary study of the deep tectonic pattern in Hebei Province and its relations with regional mineralizations |
|
|
| Abstract:On the basis of the geological data concerning deep structures acquired from various geophysical means including gravity survey and seismicprospecting, three dcep tecton/c areas have been distinguished in Hebei Province: 1) The uplift area of upper mantle in Hebei plain, where thedepth of Moho is 34-37 km beneath the surface. 2) The variable deeptectonic zone along Taihang-Yenshan mountains, where from southeast to northwest the depth of Moho gradually increases from 36 to 43 km. 3) The depression of upper mantle of Bashang plateau at the southern part of Nei Monggol plateau, where Moho lies 43-45 km below the surface.Deep tectonic pattern undoubtedly controls regional shallow geologicalfigure, magmatism, mineralizations and especially the distribution of endogenetic ore deposits formed since Yenshan epoch.The uplift area of upper mantle of Hebei plain is a large and complex fault basin formed during Cenozoic, where certain thickness of gypsumand oil layers have been accumulated. Two most promising oil fields,Dagang and Renqiu, are both located where crust is the thinnest.In the Taihang sector of the variable deep tectonic zone. Moho south of Xingtai has a relatively mild gradient of about 0.055, 1.e. a descent of 0.55 km for every lO km. Intense magmatism took place during Yenshan period, forming famous iron deposit of Hanxing type; from Xingtai to Tangxian, the gradient of Moho increases to 0.08-O.l, magmatism of Yenshan period formed mainly small and medium s:ized intrusive bodies and dykes, accompanied with gold and molybdenum mineralizations; in Laiyuan and Yixian area, the gradient of Moho changes int0 0.075, magma intruded in large quantities and many iron, copper and lead-zinc deposits resulted. The Yenshan sector of the variable deep tectonic zone can be subdivided into four minor variable' zones with three depressions of upper mantle in between. These four minor variable zones are arranged in sequence from south to north, each has its peculiar mineralizations: tungsten, molybdenurn and pyrite for the first; gold and copper for the second; iron, phosphorus, vanadium, titanium, platinum and chromium for the third and lead-zinc, fluorite and gold for the fourth zone. Of the three depressions of upper mantle, the first one is situated at Qianan-Luanxian area. having quite a few large or medium sized sedimentary-metamorphic iron deposits within it, the second one lies at Xinglong-Kuancheng area with some large or medium sized sedimentarypyrite and lead-zinc deposits in it, the third one is located somexvhere between Longhua and Weichang, embellished with pyrite and some other endogenetic deposits. |
| View Full Text View/Add Comment Download reader |
|
|
|
