作　　者： ; ; ; ; ; ; ; ;

机构地区： 华南师范大学

出　　处： 《第四纪研究》 2012年第1期158-166,共9页

摘　　要： 2011年5月对崂山山顶风化坑进行考察和采样,通过对风化坑内碎屑和坑外岩石的粉晶X射线衍射矿物分析、X射线荧光光谱化学全量分析,研究了风化坑内外的矿物风化及各元素迁移特征,对风化坑的成因过程进行探讨。研究结果表明:1)崂山山顶风化坑碎屑的英长比总是大于其周边岩石的英长比,说明风化坑的形成是花岗岩造岩矿物差异风化的结果;2)风化坑风化过程中被风化的岩石矿物主要是条纹长石和钾长石;3)风化坑中大量的Mg和Ca主要是外部加入的;4)崂山山顶风化坑内碎屑,坑外岩石面均受到化学风化的作用;5)崂山山顶风化坑内外的风化指数CIA值并不反映崂山当地的气候,山上山下CIA值的差异是风化时间长短不同造成的;6)LOI能很好地反映崂山风化坑内外风化强度的差异,说明长石主要在水解作用下发生分解,也说明了风化坑的积水成因。 After the first field trip in July of 2010, the authors made a second field trip in May of 2011 to investigate the weathering pits on the top of Mountain Laoshan, which is composed of Mesozoic granite with its highest peak 1132.7meters above sea level and located on the shore of the Yellow Sea, China. The conclusion of the first investigation is that the so-called glacial potholes in Mountain Laoshan are nothing but weathering pits as are generally found in the other granite areas around the world and then the pits on the rock surface of Mountain Laoshan are not originated from glaciers. In this paper, the evidence collected in this field investigation for the weathering origin of the pits is discussed. The detritus in the weathering pits and the surface rock outside the pits were taken from 7 weathering pits,4 of which at Laoding,the top of the mountain about 1000m＇s high, and 3 in Hualou area, northwest of Laoding with elevations of 280- 340m. X-Ray fluorescence（XRF）and X-ray diffraction （XRD）methods are used to measure the type and the amount of minerals and chemical elements of the rock samples. Based on the result of XDF and XDR, the samples＇ chemical index CIA,weathering ratios and element transformation ratio were calculated. The weathering process of the pits was analyzed and discussed in the following aspects： 1 ）The relation of the chemical weathering to the mineral weathering of the pit detritus; 2）Chemical element transferring between the pit detritus and the surface rock; 3）The different weathering intensity of the pits and the surface rock of Mountain Laoshan and its cause. The result of the study shows that： 1）The ratio between quartz and feldspar of the detritus is higher than those of the surface rock, indicating the feldspar being degenerated by weathering while the quartz remaining the same in the pits; 2）The weathered feldspars in the pit are mainly perthite and potassium feldspars owing to a lack of plagioclase in their original rocks ; 3） The elements, Ca and Mg

关 键 词： 风化坑 造岩矿物 主量元素 化学风化 崂山

领　　域： [天文地球] [天文地球] [天文地球]