青海省磨石沟地区锰矿地质特征及成矿模式  

Geological characteristics and metallogenic model of manganese deposit in Moshigou area,Qinghai

作　　者：靳杨 彭涛 赵俊芳 刚健 JIN Yang;PENG Tao;ZHAO Junfang;GANG Jian(Qinghai Provincial Non-ferrous Metal Geological Exploration Institute,Xining 810000,Qinghai,China;Qinghai Key Laboratory of Concealed Mine Exploration,Xining 810000,Qinghai,China)

机构地区：[1]青海省有色第一地质勘查院,青海西宁810000 [2]青海省隐伏矿勘查重点实验室,青海西宁810000

出　　处：《矿产与地质》2023年第4期665-678,共14页Mineral Resources and Geology

基　　金：青海省清洁能源矿产专项资金勘查项目“青海省格尔木市磨石沟地区锰多金属矿普查”(项目编号:2021074047kc016)资助。

摘　　要：随着近年在东昆仑南坡俯冲碰撞杂岩带找矿勘查工作的开展,磨石沟地区中—新元古界万宝沟群碳酸岩组黑色岩系中发现了海相沉积锰矿。经初步估算,磨石沟锰矿334资源量为115.9万t,属小型规模矿床。研究区内含锰岩层主要为万宝沟群碳酸岩组的上段白云岩、板岩段(Pt_(2-3)W^(2b))及下段灰岩段(Pt_(2-3)W^(2a))的地质体;区内的F_(4)、F_(24)断层构造是形成含锰盆地的主要地质构造并且也是含锰物质热液运移通道;研究区内圈出8处含锰岩系地质体,并且在含锰岩系地质体内共圈出17条锰矿体,主矿体6条;通过物相分析,地表以氧化锰矿为主,深部以碳酸锰为主;通过w(CaO+MgO)/w(SiO_(2)+Al_(2)O_(3))比值为0.05~0.57,平均0.26,磨石沟地区锰矿属于中铁高磷酸性碳酸锰矿。w(Al)/w(Al+Fe+Mn)、w(SiO_(2))/w(Al_(2)O_(3))、Fe—Mn—(Cu+Co+Ni)×10比值表明磨石沟地区锰物质来源主要是陆源碎屑及海底喷流。初步提出磨石沟地区的含锰岩系为一套有热水沉积参与的滨海-浅海相台盆台沟相沉积岩。With the development of prospecting and exploration work in the subduction collision complex belt on the south slope of East Kunlun in recent years,marine sedimentary manganese deposits have been found in the black rock series of carbonatite system of Wanbaogou group of Meso-Neoproterozoic in Moshigou area.It is preliminarily estimated that the resources quantity of 334 in Moshigou manganese deposit is 1.159 million tons,which is a small-scale deposit.The manganese-bearing strata in the study area are mainly the geological bodies of the upper dolomite of slate section(Pt_(2-3)W^(2b))and the lower limestone section(Pt_(2-3)W^(2a))of the carbonatite system of Wanbaogou group,the F_(4)and F_(24)fault structures in this area are the main geological structures that form the manganese-bearing basin and the hydrothermal migration channels of manganese-bearing materials.There are 8 geological bodies of manganese-bearing rock series in the study area,and a total of 17 manganese orebodies and 6 main orebodies are delineated in the manganese-bearing rock series.According to phase analysis,the surface is dominated by manganese oxide ore,and the deep part is dominated by manganese carbonate.The ratio of w(CaO+MgO)/w(SiO_(2)+Al_(2)O_(3))is 0.05-0.57,with an average of 0.26.The manganese ore in Moshigou area belongs to medium iron and high phosphate manganese carbonate ore.The ratios of w(Al)/w(Al+Fe+Mn),w(SiO_(2))/w(Al_(2)O_(3))and Fe-Mn-(Cu+Co+Ni)×10 indicates that the source of manganese in Moshigou area is mainly terrigenous debris and submarine exhalation.It is preliminarily proposed that the manganese-bearing rock series in the Moshigou area is a set of coastal-shallow marine platform basin-platform ditch sedimentary rocks with hot water deposition.

关 键 词：锰矿 海相沉积 地质特征 控矿因素 成矿模式 磨石沟 

分 类 号：P618.32[天文地球—矿床学]