1. Material composition of the geosynclinal tectonic LayerThe geosynclinal tectonic layer is mainly composed of the following two parts: sandyslate rocks of Precambrin and volcanic rocks inbeded within the sand-slate ...1. Material composition of the geosynclinal tectonic LayerThe geosynclinal tectonic layer is mainly composed of the following two parts: sandyslate rocks of Precambrin and volcanic rocks inbeded within the sand-slate rocks.The sandy-slate rocks embrace the chemical compositional characteristics of light metamorphic rocks: SiO<sub>2</sub>=54.56<sup>8</sup>1.63(Wt%), with average of 63.96(wt%)(n=58, the same as following); Al<sub>2</sub>O<sub>3</sub>=9.47<sup>1</sup>7.75(wt%), with average of 15.36(wt%), and Al<sub>2</sub>O<sub>3</sub>】K<sub>2</sub>O+Na<sub>2</sub>O+CaO; the content of (FeO+Fe<sub>2</sub>O<sub>3</sub>) varies greatly with FeO】Fe<sub>2</sub>O<sub>3</sub>; (CaO+MgO)=0.78<sup>9</sup>.22 (wt%)with average of 23 (wt%), and MgO】CaO; the ratios of K<sub>2</sub>O/Na<sub>2</sub>O rang from 2 to 4(】1). By comparing all this chemical data with that of the other kind rocks, We can know that the sand y-slate rocks were the eunic and /or bathyal sediments which formed under the strongly active eugeosynclinal tectonic setting.展开更多
文摘1. Material composition of the geosynclinal tectonic LayerThe geosynclinal tectonic layer is mainly composed of the following two parts: sandyslate rocks of Precambrin and volcanic rocks inbeded within the sand-slate rocks.The sandy-slate rocks embrace the chemical compositional characteristics of light metamorphic rocks: SiO<sub>2</sub>=54.56<sup>8</sup>1.63(Wt%), with average of 63.96(wt%)(n=58, the same as following); Al<sub>2</sub>O<sub>3</sub>=9.47<sup>1</sup>7.75(wt%), with average of 15.36(wt%), and Al<sub>2</sub>O<sub>3</sub>】K<sub>2</sub>O+Na<sub>2</sub>O+CaO; the content of (FeO+Fe<sub>2</sub>O<sub>3</sub>) varies greatly with FeO】Fe<sub>2</sub>O<sub>3</sub>; (CaO+MgO)=0.78<sup>9</sup>.22 (wt%)with average of 23 (wt%), and MgO】CaO; the ratios of K<sub>2</sub>O/Na<sub>2</sub>O rang from 2 to 4(】1). By comparing all this chemical data with that of the other kind rocks, We can know that the sand y-slate rocks were the eunic and /or bathyal sediments which formed under the strongly active eugeosynclinal tectonic setting.