镇江圌山珍珠岩矿床地质特征及成因

On the Characteristics and Genesis of Perlite Deposit in Cuishan, Jiangsu

圌山珍珠岩矿是我省首次发现的一个大中型矿床。它不仅填补了我省珍珠岩矿的空白,而且将成为省内建材、冶金、化工等较有前景的原料基地。矿床地质特征矿区位于扬子准地台下扬子褶皱带,宁镇穹断褶东东端埤孟复式背斜北东翼、圌(山)—扬(中)中生代火山断陷盆地南西缘。矿区主要岩石特征矿区出露地层简单,主要为白垩系下统圌山组和上党组火山岩。

The Cuishan perlite deposit is a large meddle sized deposit, first one in Jiangsu Province. The paper studies and describes the characteristics of its geology, main rock type, petrochemistry , trace elements and chemical composition of perlite. Based on such a research result. the author also carries out preliminary research on its genesis and mechanism. The results show that the subduction and compression of Kula plate resulted in large amount of acidic magma eruption along fault belt. At the surface,the pressure suddenly decreased and large amount of volatile component lost and the viscosity of magma greatly increased. Then the cooled magma absorbed large amount of water and altered to perlite. Finally,the paper proposes the prospecting criteria for perlite deposit. The perlite usually associates with bentonite,zeolite constituting series deposits. Acidic lava and clastic rock in volcanic basin is another criteria.