Abstract:Following a general description of zeolite ore deposits in Jilin Province, this paper emphatically deals with geological condition of clinoptilolite ore deposits and analeime ore deposits belonging respectively to fresh-water lake facies pyroclastic rock type and saline lake facies type. The former was formed in rifted depression basin of volcanic eruption characterized by open drainage and low alkalinity(pH=7-9), in which the acidic pyroclastic materials were deposited during Cretaceous by fissure-central eruption,which,through late devitrification, formed silica-rich zeolite ore deposit predominantly composed of subclinoptilolite, while the latter occurred in a geological environment of confined basin. The drying of water in the lake and the addition of alkalic elements of volcanic rocks through solution caused the eventual formation of saline lake with high salinity and alkalinity. Under this condition the vitric fragments and tuff of pyroclastic rocks turned readily into zeolite ore deposit of low-silica analcime through late stage devitrification. An analysis of minerogenetic condition of zeolite ore deposits in Jilin Province indicates that the mineralization of zeolite has been mainly controlled by dislocation structure since Mesozoic. The zeolite ore bedies mostly occur in unconformable contact surface of acidic pyroclastic rocks, surfaces of strata separating various eruptive cycles, volcanic clastic rocks constituting hanging wall and floor of coal beds as well as fracture zones where underground water circulates easily. Early Cretaceous and Late Jurassic are the two main minero-genetic epochs for zeolite ore deposits in Jilin Province. The four substantial ore-bearing beds are K21(Yingcheng Formation, Sankeyushu Formation, wulin formation, and Liufangzi Formation), J 33(Baoshi Formation, Anmin Formation, Linzitou Formation, and Laotougou Formation), and J 31(Lamenzi Formation).The zeolite ore-bearing volcanic sequences mainly belong to calcic-alkalic rocks of normal Pacific type. The country rocks are calcic-alkalic rocks with high acidity and alkalinity, and alkali-rich vitreous rocks with high silica are most favorable for mineralization.
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刘志贤.1985.吉林省沸石矿床地质特征及成矿规律[J].矿床地质,4(3):79~84,94.1985.Geological features and minerogenetic regularity of zeolite ore deposits in Jilin province[J].Mineral Deposits4(3):79~84,94
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