中国红透山太古宙块状硫化物矿床集中区地质

GEOLOGY OF THE ARCHEAN MASSIVE SULFIDE ORES PROVINCE IN NORTHERN LIAONING, CHINA

中国辽宁省浑河断裂以北地区(以下简称辽北地区),是中国重要的太古宙块状硫化物矿床的集中区。全区集中分布着块状硫化物矿床、矿点和矿化点共100余处。在诸矿床中红透山矿床的规模最大—为一中型锌—铜块状硫化物矿床。 辽北地区由于集中分布着众多的块状硫化物矿床,因此称之为块状硫化物矿床集中区。在该集中区内,块状硫化物矿床按其工业利用价值可分为两类:锌—铜型块状硫化物矿床和块状硫铁矿矿床(也含黄铜矿、闪锌矿矿体),它们为同期同成因的矿床组合。 在本区块状硫化物不只是单纯的矿石具块状构造之意,而是用来描述硫化物矿物在矿石中占主导(大于50%)的同期同成因的矿床组合。

The massive meta-sulfide ores in the descriptive area occur in Anshan Group, Archean eon, of 3. 1b. y.old. The occurrence of the ores is strictly bounded to the 'thin strata interbed' which can be correlated perfectly.The ore containing rock is basalt at the lower horizon and intermediate to acidic calc-alkalinic volcanids at the upper horizon. The ore is located in the acidic volcanic rocks. The REE pattern of the rock series is compatible with the Bulawayan.s in South Africa, showing its mantle derivation.The main ore minerals are pyrite, pyrrhotite, sphalerite and chalcopyrite. Their content usually exceeds 70%. The ore bodies are various vein-shaped. They are parallel to or cross-cutting the schistocity.Expanding contracting and thinning out of the vein are very common along its extension, (please refer to 《The metamorphism and reempiacement of the Archean Hungtoushan massive sulfide ore dleposit,North Liaoning province China》 for detail. )In the ore extensively developed the palimpsest structure (banded structure, blastocolloidal structure) and metamorphic structure (crumpling structure, annealingttexture-macroporphyroblasts,annealing twin crystals, three 120° in interfacial angle, fibrous texture, remobile differtial migration texture) . They are evidences of the ore, s origination and metamorphic history.Both the hanging wall and the bottom wall of the ore were alteied, and later through metamor-phism they turned into cordierte-anthophyllite rocks and again were tremolite and phlog? pitized in subsequent metamorphism. There weie also silicification, sericitizatin, chloritization and caibonatizati-onoof possible metamorphic hydro thermal solution dlteration of minor significance in regarding to the ore body. There are an unanimity in the sulphur istopic composition among the individual deposits, the individual ore bodies and the various ores in this area. An average of 60 samples6s34‰ gives a value of 0. 81.The massive salfide ore deposits in this area may be correllated with sea-bottom volcanic cmanationoo?e deposits in Archean greenstone belt all over the world.