柴达木盆地宗马海湖地区钾盐矿床成矿规律与成矿预测研究

Predication of Potassium Salt Deposit in Zongmahaihu Area of Qaidam Basin in Qinghai Province

摘要:

研究区位于柴达木盆地北部边缘，属柴达木盆地中—新生代盐类成矿区。该次研究了浅部、中深部及深层储层特征、卤水钾盐的赋存规律及构造控矿理论。浅部卤水钾盐依据KCl含量，分为工业品位区、边界品位区、有浅层卤水区及无浅层卤水区。中深部卤水钾盐分布于山间古冲洪积平原（Ⅰ234）和马海湖次级洼陷（Ⅰ254）中，矿层厚度较大的区域在马海湖次级洼陷（Ⅰ254）北部，主要分布于全新统—更新统含盐系中，计算深度297.22m。深部卤水钾盐，厚度较薄者分布于冷湖六号、冷湖七号构造以北地区的一层至数层的砂岩及砂砾岩层中，自南东向北西由深变浅，分布于上新统，含卤水层段厚约50~250m。厚度较大者分布在赛什腾山山前冲洪积带，北至驼南断裂，南大致至ZK4012孔一线，孔隙卤水层累计深度达1265.14m，分布于全新统—上新统，是今后寻找深层卤水钾盐矿最重要的找矿区域。

Abstract:

The study area is located in the northern edge of Qaidam basin. It belongs to MesozoicCenozoic salt mineralization area in Qaidam Basin. The characteristics of shallow, middle and deep, deep reservoirs, the occurrence law of brine potassium salts and the theory of structural ore control have been studied. The shallow brine potassium salt can be divided into industrial grade area, boundary grade area, shallow brine area and nonshallow brine area according to the content of KCl. Potassium salt in the middle and deep part distributes in the intermountain paleoalluvial plain （Ⅰ234）and Mahaihu secondary degression （Ⅰ254）, brine potassium salts with large thickness is located in the north of Mahaihu secondary degression （Ⅰ254）, and distributed in HolocenePleistocene saltbearing system. The thickness of brinebearing layers is about 50~250m. The thicker ones are distributed in the alluvialdiluvial belt in front of Saishteng mountain, the north is to Tuonan fault, and the south is to the ZK4012 hole. The accumulative depth of porous brine layer is 1265.14m, and distributed in HolocenePleistocene. It is the most important prospecting area for deep brine potash deposits in the future.