摘要
洞中松多铅锌多金属矿床位于冈底斯多金属成矿带东部,矿体主要赋存于前奥陶系松多岩群和中二叠统洛巴堆组,围岩多为碳酸盐岩,且蚀变强烈.已圈定2条矿化蚀变带和9个主要铅、锌矿(化)体,矿化带长度约2620～4100 m,宽约50～1140 m;矿(化)体呈层状和似层状产出,矿(化)体长为120～2881 m,水平厚度为2.1～13.1 m.矿石中主要有用元素为铅和锌,伴生有益组分为银、铁、铜、硫.矿石矿物主要为磁黄铁矿、黄铁矿、白铁矿、黄铜矿、方铅矿、闪锌矿等,脉石矿物主要为石英、透辉石、石榴石、绿泥石、绿帘石、方解石、长石等.铅锌矿化与岩浆活动和大气降水有关,主要与燕山晚期—喜马拉雅早期的岩浆—热液有关.同时矿床的形成与印度—欧亚板块的碰撞和青藏高原的隆起有关.本文首次对洞中松多矿床的成因进行了初步的探讨,通过对矿床地质特征、成矿物质来源等的分析讨论,认为洞中松多铅锌多金属矿床是构造—岩浆等长期活动的结果,断裂构造为铅锌多金属矿床的成矿物质提供了运移通道和富集空间,燕山晚期—喜马拉雅早期的深层岩浆为矿床提供了主要成矿物质和热源,属于矽卡岩型—热液改造矿床.
The Dongzhongsongduo lead-zinc polymetallic deposit is located in the east part of the eastern Gangdese polymetallic mineralization belt. The ore body has mainly occurred as strumiform and stratoid structures in the carbonatite within the skarns of the pre-Ordovician Songduo group complex and the mid- permian Luobadui formation. Wall rock is made up of carbonatite and has strongly altered. Two alterations and nine main ore zones have been delineated. Lead and zinc are the main useful elements in the ore, and silver, iron, copper, sulfur as beneficial groups in the ore. The length of the layered ore-bodies is between 2620 and 4100 m, 50~150 m and the thickness is between the Songduo group complex and the Luobadui formation. The ore is 120~2881 m long and 2.1~13.1 m thick. The footwall of the ore are limestone and tuff and the hanging wall is crystal tuff. The ore minerals include pyrrhotine, pyrite, chalcopyrite, galena and sphalerite, etc. The gangue minerals include quartz, diopside, garnet, chlorite, epidote, calcite and feldspar, etc. The mineralization of lead and zinc was closely related to magmatic activity and meteoric, especially related to the magmatic hydrothermalism which had intruded into carbonatite in the period of late Yanshan-early Himalayas. Presumably, the formation of lead and zinc deposit has been related closely to the plate collision of the Indian-Eurasian Plate and the uplift zone in the Tibetan Plateau. This is the first study of the causes of the deposit. Through an analysis and discussion of the geological characteristics and metallogenic source materials, we believe that the Dongzhongsongduo lead-zinc polymetallic deposit has been related to the tectonic and magmatic activities. The structure has provided motive channels and accumulated space for the deposit. And the deep magma of late Yanshan period-early Himalayas has provided the main ore-forming materials and energy for the deposit. Therefore, it is considered that the Dongzhongsongduo lead-zinc polymetallic deposit belongs to stratum controlled skarn type and hydrothermal transformation deposit.
出处
《兰州大学学报（自然科学版）》
CAS
CSCD
北大核心
2013年第1期24-31,共8页
Journal of Lanzhou University(Natural Sciences)
基金
国家自然科学基金项目(41262001)
甘肃省科技支撑基金项目(1104FKCA116)
甘肃省自然科学基金项目(1010RJZA020)
甘肃省高等学校研究生导师科研项目(1101-07)
兰州市科技计划基金项目(2011-2-89)
关键词
洞中松多
铅锌矿床
地质特征
矿床成因
西藏
Dongzhongsongduo
lead-zinc deposit
geologic characteristics
origin of deposit
Tibet
