对马山-大宝山变质成因磁黄铁矿不同组成结构的认识

马山和大宝山矿床均为块状硫化物矿床。显微镜研究表明，两矿床中磁黄铁矿主要均由胶黄铁矿变质形成，但组成结构上却有较大区别。马山矿床主矿体中单斜磁黄铁矿（Ｍｐｏ）一般少于六万磁黄铁矿（Ｈｐｏ），而大宝山矿床主矿体中单斜磁黄铁矿和六万磁黄铁矿一般近相等。通过对导致矿床发生热变质的中生代燕山期岩体的研究，认为岩体成因类型的不同及所含热量的差异是导致两矿床变质成因磁黄铁矿组成结构不同的主要原因

RECOGNITION OF DIFFERENT COMPOSITIONAL TEXTURES OF METAMORPHISM-ORIGIN PYRRHOTITES FROM MASHAN AND DABAOSHAN DEPOSITS

Mashan and Dabaoshan deposits situated in Tongling district of lower Yangtze and north Guangdong district of Nanling respectively,both belong to the massive sulfide deposits. Microscope research demonstrates that the pyrrhtites from the two deposits are mainly formed from melnikovites, but their compositional textures are different from each other. That is, monoclinic pyrrhotite is generally less than hexagonal pyrrhotite in quantity in the bedded main ore bodies of Mashan deposit, while they are approximately equal in amount in the bedded main ore bodies of Dabaoshan deposit. The study of Mesozoic Yanshanian plutons responsible for metamorphism of the deposits suggests that the different genetic types of plutons and their different thermal quantity included are main cause for the different compositional textures of metamorphism- origin pyrrhotites of these two deposits.