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长江中下游燕山期中酸性岩浆的形成与幔隆带构造叠加和印支期深层拆离作用有关 ,但最终起决定作用的是燕山期 NNE向陡倾左行压扭斜滑深切断裂。由于该组断裂深切地幔隆起 ,促使地幔物质和热流上涌 ,并穿入印支期因拆离作用形成的不同深度的层状岩浆房 ,使岩浆房中的岩浆与壳源重熔岩浆混合。此外 ,沿着陡倾剪切带尚可出现新的局部重熔 ,形成再度混合的脉状岩浆房。区内岩浆的成因、运移上升和侵入定位的构造动力作用是统一的 ,都是压扭构造应力场作用的结果 ;只是在不同深度 ,不同部位 ,不同阶段的不同表现而已。NNE向左旋压扭斜滑断裂是本区驱动岩浆上升和运移的主要因素。
The Yanshanian intermediate-acidic magma formation in the middle and lower reaches of the Yangtze River is related to the superimposition of the mantle-long belt and the deep detachment during the Indo-Chinese epoch. However, the final decisive function is the NNE steep left-trending diagonal slip-shear fault in the Yanshanian period. Because of the intensive uplift of the mantle, the mantle material and heat flow upwells and penetrate into stratified magmatic chambers of different depth formed during the Indo-Chinese detachment so that the magma in the magma chamber is mixed with the reef magma. In addition, new partial remelting can occur along steep shear zones to form a re-mixed vein magma chamber. The formation magmatism, tectonic motions of migration and intrudement are all unified, all of them are the result of stress-torsional tectonic stress field. They only show in different depths, different parts and different stages. NNE leftward twisting and slip-slip faults are the main factors driving the magma to rise and migrate in this area.