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位于湖南中部的城步铺头黄铁矿床,是产于泥盆系基维特阶的层状矿床,1984年作者在本刊报导过这个矿床的沉积环境。根据新的资料,再次对它的成因进行研究。该矿床位于华南古大陆边缘裂谷系的北东向深水盆地中,含矿岩系由暗色的硅质岩—泥灰岩组成,矿体呈层状整合产出,以黄铁矿为主,硫同位素以富含32S为特点(δ34S=-17.4‰~-30.10‰)。含矿岩系及矿石中,有机质含量较高(3%~5%),有机质类型为腐殖—腐泥混合类型,成熟度较高。矿石具致密块状及条带状构造,由大量草莓状黄铁矿组成,它们主要出现在致密块状矿石中。矿石及含矿围岩的稀土元素、微量元素组成,与现代大洋裂谷或隆起区中的热液沉积物的特征相似,表明它们具有相同的来源和成因,应属海底热液喷流沉积矿床,大量存在的有机质,对于矿床的形成也起了重要的作用。
The Chengbupu head-pyrite deposit in central Hunan is a stratiform deposit developed in the Devonian-Kivtwort. In 1984, the author reported the sedimentary environment of this deposit. According to new information, once again its cause of research. The deposit is located in the NE-trending deep-water basin of the southern continental margin rift system in South China. The ore-bearing rocks are composed of dark siliceous rocks - marl. The ore bodies are layered and integrated with pyrite, Sulfur isotopes are characterized by rich 32S (δ34S = -17.4 ‰ ~ -30.10 ‰). In the ore-bearing rock series and ore, the organic matter content is high (3% ~ 5%), and the organic matter type is humic-sapropelic mixing type with high maturity. Ore has a dense block and strip structure, composed of a large number of strawberry-like pyrite, which mainly appear in the dense lump ore. The REE and trace element compositions of ore and ore-bearing rocks are similar to the features of hydrothermal sediments in modern ocean rifts or uplifts, indicating that they have the same source and genesis and should be submarine hydrothermal jet deposits The presence of large amounts of organic matter also plays an important role in the formation of the deposit.