热水沉积岩及矿物岩石标志

热水沉积物不同于普通沉积物 ,主要与热水流体类型有关。文中把热水流体划分为中高温热水流体与中低温热水流体。中高温热水沉积岩包括钾长石岩、硅质岩、电气石岩、钠长石岩、萤石岩 ;中低温热水沉积岩包括碳酸盐、硫酸盐等岩石。钾长石岩是文中确定的一种标准高温热水沉积岩 ,热水沉积钾长石以冰长石和钡长石为主 ;热水沉积碳酸盐矿物一般为铁、镁、锰、钙碳酸盐 ,碳酸盐的形成与CO2 和H2 O的不混溶温度有关 ,一般在不混溶温度 ,即 2 66℃以下生成 ,或在海水补偿线以上形成。热水沉积岩中有热水交代蚀变岩夹层 ,尤其是在高温热水活动区 ,可以交代泥质、钙泥质沉积物形成热水交代沉积岩 ,包括方柱石黑云母岩、透辉石透闪石岩、夕卡岩、绿泥石岩等。根据对霍各乞铜多金属矿床的研究 ,热水交代透辉石透闪石岩的稀土总量较低 ,表现为轻稀土富集 ,重稀土亏损 ,稀土配分模式表现为正Eu异常

HYDROTHERMAL SEDIMENTARY ROCK AND INDICATORS OF MINERALS AND ROCKS

Hydrothermal solution sediment differs from the common sediment and is mainly related to hydrothermal fluid type. This paper classifies the hydrothermal solutions into the middle high temperature type and the middle low temperature type. Sedimentary rocks of middle high temperature hydrothermal solution include potash feldspar rock, silicalite, hyalotourmalite, albite rock; and the fluorite rock; and the sedimentary rocks of middle low temperature hydrothermal solution consist of hydrochloric rock, sulphate rock etc. Potash feldspar rock is identified as a standard type of middle high hydrothermal solution sedimentary rock in this paper and mainly includes adularia and baryta feldspar. Hydrothermal solution sedimentary carbonate minerals generally include Fe carbonatite, Mg carbonatite, Mn carbonatite and Ca carbonatite, and their forming is related to immiscibility temperature of H 2 O and CO 2 . That is to say, the carbonate is formed below 266℃, or above the seawater compensation level. There are interbedded strata of hydrothermal solution metasomatic alteration rock in hydrothermal solution sedimentary rock. Especially, hydrothermal solution metasomatic sedimentary rocks are formed through metasomatosing argillaceous and Ca argillaceous sediment in the high temperature hydrothermal solution active regions. These sedimentary rocks include scapolite corneit, pitkarantite, scarn, chloritite rock etc. The study of the Huogeqi Cu polymetal deposit shows that the total REE content is relatively low in hydrothermal solution metasomatic pitkarantite rock, rich in light REE and deficient in heavy REE, and that the model of the REE distribution is of positive abnormality of Eu.