【摘要】 采用Rf/φ法对姑婆山-花山花岗岩基及其热接触变质围岩进行了系统的应变测量,共测量了153个三维有限应变测量点、1.5万余个应变标志体。结果表明:①姑婆山-花山花岗岩基热接触变质围岩和早期侵位的牛庙、杨梅山独立侵入体及里松和望高单元以压扁型应变为主,晚期侵位的新路单元则为拉长型应变。②姑婆山-花山花岗岩基的平均应变强度和平均压缩率均小于热接触变质围岩的平均应变强度和平均压缩率,且岩基内从早期单元到晚期单元(除新路单元外)平均应变强度和平均压缩率均逐渐减小;热接触变质围岩内应变强度和压缩率向岩基接触面方向递增,存在较明显的应变强度梯度和压缩率梯度。另外岩基南侧以碳酸盐岩为主的热接触变质围岩的压缩率远高于北侧以碎屑岩为主的围岩压缩率。③姑婆山-花山花岗岩基应变型式表现为近接触变质围岩及各花岗岩单元边部的应变椭圆长轴多与接触界线相协调,最小主应变轴与接触界线多呈大角度相交;各单元中部的应变椭圆展布则比较凌乱、定向性不明显。上述特征表明,姑婆山-花山花岗岩浆的多期脉动侵位在岩体及其围岩内产生较强的应变叠加,而岩浆内部的主动侵位动力应是造成岩体及其热接触变质围岩变形的主要动力,且在岩浆多次脉动侵位过程中,岩体内早期单元及其围岩主要遭受的是径向挤压作用。更多还原

【Abstract】 A systematic finite strain measurement using the Rf/φ method has been conducted throughout the Guposhan-Huashan granitic batholith and its thermal contact metamorphic country rocks,for a total number of 15000 strain markers at 153 field stations.The results show that:(1)the country rocks and early emplaced intrusions and intrusive units such as the Niumiao and Yangmeishan intrusions,and Lisong and Wanggao units are dominantly characterized by flattening strain,whereas the late emplaced Xinlu unit by constrictional strain;(2)the mean strain intensities and compression rates of the batholith are less than that of the country rocks.The older intrusions and intrusive units show higher mean strain intensities and compression rates than the younger ones.There clearly exists a strain intensity gradient and compression rate gradient within the country rocks so that both strain intensity and compression rate increase toward the contact surface.The thermally metamorphosed country rocks of dominantly carbonates on the south side of the batholith show higher compression rate than the thermally metamorphosed country rocks of mainly clastic rocks on its north side;and(3)Within the country rocks,the long axes of strain ellipsoids,measured adjacent to the batholith contact and at the border of each intrusive unit,are mostly parallel to the contact surface.Their short strain axes mostly make nearly right angle with the contacts.In contrast,the ellipsoids measured in the central area of each intrusive unit show no preferred orientation but a random order.It is suggested that these strain characteristics and strain patterns were results of repeated strain superposition caused by multi-pulse emplacements of granitic magmas,and that the prolonged,repeated deformation of the country rocks and the early intrusive units was caused by magmatic internal force.It is obvious that the deformation resulted from radial compression(or push)associated with the multi-pulse magma ascent and emplacement.更多还原