CAJ | 학술논문

通过对石头城地区上侏罗统张家口组三段第五层石英粗面岩进行了较详细的岩相学和岩石化学分析，研究了各样品的主量元素、火山岩分类、碱度、岩石系列和矿物结晶分异等特征，初步探讨了石英粗面岩形成的构造环境。结果表明：石英粗面岩具有富硅、富碱、富钾、低钙镁、铝过饱和等岩石学特征，推断原岩为大陆地壳，属弱造山环境的产物。与典型矿床相比，石头城地区石英粗面岩的岩石学特征和形成构造环境与大扇子沟铀矿床赋矿粗面岩特征相似，石头城地区应找寻大扇子沟式铀矿床，为该区铀矿找矿指明了方向。
통과대석두성지구상주라통장가구조삼단제오층석영조면암진행료교상세적암상학화암석화학분석，연구료각양품적주량원소、화산암분류、감도、암석계렬화광물결정분이등특정，초보탐토료석영조면암형성적구조배경。결과표명：석영조면암구유부규、부감、부갑、저개미、려과포화등암석학특정，추단원암위대륙지각，속약조산배경적산물。여전형광상상비，석두성지구석영조면암적암석학특정화형성구조배경여대선자구유광상부광조면암특정상사，석두성지구응조심대선자구식유광상，위해구유광조광지명료방향。
Through detailed petrographic and petrochemical analysis on the fifth layer of quartz trachyte in third section of Upper Jurassic Zhangjiakou Formation in Shitoucheng area,this paper studied the features such as major elements contents,types of igneous rocks,alkalinity,lithological series and mineral crystalli-zation differentiation,and it preliminarily discussed the structural environment of formation of quartz tra-chyte.It is suggested that quartz trachyte has petrological characteristics such as rich-silicon-alkali-potassium and low-calcium-magnesium as well as alumina oversaturation.Hence it is concluded that the protolith is continental crust which is a kind of product of weak orogenesis.In comparison to other typical deposits,the petrological characteristics and formational structural environment of quartz trachyte in Shitoucheng area is similar to the characteristics of the ore-bearing trachyte of Dashanzigou uranium deposit.It is clear that Dashanzigou type uranium deposits shall be the target in prospecting works of Shitoucheng area.