山东单县岩盐矿床地质特征及找矿模型浅析

Study on Geological Characteristics and Prospecting Model of Rock Salt Deposit in Shanxian County in Shandong Province

摘要:

近年，山东省地质科学研究院在山东单县地区岩盐矿找矿取得重大突破，预测岩盐矿总资源量超过242亿t。单县岩盐矿位于黄岗潜凹陷南部，岩盐矿赋存层位为古近纪官庄群大汶口组中段，岩性为深灰色泥岩、石盐互层，是一套浅湖相沉积建造。岩盐矿层赋存形态简单，呈层状产出，产状稳定，呈EW向展布，倾向近S向，倾角平缓。区内揭露岩盐矿层35层，单矿层平均厚度0.82~32.16m，累计厚度240.41m，NaCl平均品位38.91%~90.18%。通过对单县岩盐矿地质特征等综合研究，大致查明了单县岩盐矿矿层的形态、产状、规模、分布、厚度、矿石特征及矿层地球物理特征等。根据矿床成因类型，结合岩盐矿具体特点，认为该区岩盐矿找矿标志主要有地层、地球物理、矿床特征等3个主要标志，研究区东南部成矿潜力较大。

Abstract:

In recent years, Shandong Institute of Geological Sciences has made great progress in rock salt prospecting in Shanxian county in Shandong province.. It is predicted that total resources of rock salt deposit will exceed 24.2 billion tons. Shanxian rock salt deposit is located in the south of Huanggang subdepression. The rock salt deposit is located in the middle part of Dawenkou formation of Guanzhuang group in Paleogene. The lithology is a shallow lacustrine sedimentary formation of dark gray mudstone and interbedded stone and salt. The occurrence form of rock salt deposit is simple. It occurs in layers with stable occurrence. Its strike is close to EW direction and inclines to S direction with gentle dip angle. There are 35 layers of exposed rock salt ore in the area. The average thickness of single ore bed is 0.82~32.16m, cumulative average thickness is 240.41m, and average grade of NaCl is 38.91%~90.18%. Through comprehensive study on geological characteristics of rock salt deposit, the shape, occurrence, scale, distribution, thickness，ore characteristics and geophysical characteristics of the rock salt deposit in Shanxian county have been identified. According to genetic types of the deposits, combining with characteristics of rock salt deposit, it is regarded that strata, geophysics and occurrence of ore bodies are main prospecting indicators. There is a large metallogenic potential in the southeast of the study area.