摘要
南迦巴瓦构造结东侧结合带经历了多期次构造活动变形。通过系统地质调查、剖面测制和取样试验,对其岩石分布、成分、结构、物理力学性质和结合带的构造特征等进行了研究,结果显示:岩石类型多,矿物成分和含量差异大,变质作用复杂,岩石各向异性、抗风化能力差异明显;各类岩片和岩块的物理力学特性差异大;同类岩片和岩块受云母、角闪石含量和变质、风化、塑性变形程度差异等因素的影响,物理力学特性差异也较大;结合带内部和两侧边界总体上未见大的脆性断裂,岩层韧性剪切和塑性变形特征明显,各类岩片以突变焊接接触为主。该结合带现今为一套岩石建造,脆性断裂总体不发育。
The Namjagbarwa structural knot belongs to passive continental margin and it has experienced multiple tectonic deformation in the geological historical period.Through geological survey,profile measurement and large number of sampling test,the distribution,composition,structures,physical and mechanical properties of the rocks and the structural characteristics in this junction zone are studied.It is showed that the rock types in the area are varied with different mineral compositions and content and with complex metamorphism.The rock anisotropy and weathering extent are obvious with different physical and mechanical properties,which are affected by the content difference of mica and hornblende,and by the influence of metamorphism,weathering extent,plastic deformation degree and mica enrichment,etc.There are no large brittle faults in the inner and both sides of the junction zone boundary,instead of obvious ductile shear and plastic deformation.All kinds of rock sheets mainly exhibited abrupt welding contacts.In general,the junction zone is composed of a set of rock formations,and brittle fractures are not developed.
引文
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