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对采自四川北部旺苍-南江地区(32.14°N,106.17°E)中寒武世陡坡寺组12个采点的120块定向标本进行的系统岩石磁学和古地磁学研究表明:紫红色细砂岩的剩磁方向表现为单分量(D=29.3°,I=-19.4°,k=283.7,α_(95)=7.3°),所对应的古地磁极位置(39.5°N,247.3°E,置信椭圆为:dp=4.0°,dm=7.6°)与扬子地块晚二叠世极位置基本重合.红色泥岩的剩磁方向由两个组分携带,其中低温剩磁分量在地理坐标下与现代地磁场方向基本一致;高温剩磁分量(D=129.1°,I=23.6°,k=44.6,α_(95)=7.8°)可通过褶皱检验,对应的古地磁极位置为39.5°S,185.1°E,(置信椭圆为:dp=4.4°,dm=8.3°),我们认为扬子地块在中寒武世处在南半球低纬度地区.
Systematic rock magnetism and paleomagnetism studies of 120 directional specimens collected from 12 sites in the Middle Cambrian Steppe Group in the Wangcang-Nanjiang region (32.14 ° N, 106.17 ° E) in the northern part of Sichuan Province show that the purple-red The direction of remanence of fine sandstone is single component (D = 29.3 °, I = -19.4 °, k = 283.7, α 95 = 7.3 °) and the corresponding paleomagnetic pole position (39.5 ° N, 247.3 ° E , The confidence ellipse is: dp = 4.0 °, dm = 7.6 °) basically coincides with the Late Permian polar position of the Yangtze block.The direction of remanence of red mudstone is carried by two components, of which the low temperature residual magnetic component is under the geographic coordinates And the direction of modern geomagnetic field is basically the same. The high temperature residual magnetic components (D = 129.1 °, I = 23.6 °, k = 44.6, α 95 = 7.8 °) can pass the fold test and the corresponding paleomagnetic pole position is 39.5 ° S , 185.1 ° E (confidence ellipse: dp = 4.4 °, dm = 8.3 °). We think that the Yangtze block was located in the low latitude of the southern hemisphere during the Middle Cambrian.