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对采自蓟县剖面的蓟县系杨庄组(~1350Ma)紫红色泥质白云岩样品开展了详细的古地磁研究,成功分离出两个剩磁分量.低温分量A在地理坐标系下与现代地磁场方向接近,被解释为重磁化分量.高温稳定剩磁分量B能够在99%置信水平上通过褶皱检验(褶皱的时代为中晚侏罗世)和95%置信水平上通过倒转检验.岩石磁学实验表明其携磁矿物为赤铁矿.其平均方向在构造校正前为D/I=77.6°/?24.3°(κ=5.4,α95=18.3°),校正后为D/I=72.2°/11.5°(κ=24.6,α95=7.9°,N=15),该分量被解释为原生剩磁.相应的视磁极位置为(17.3°N,214.5°E,dp/dm=4.1°/8.0°).对现有高质量古地磁极拟合结果表明,华北地台、Laurentia、Baltica和Siberia大陆在1800~1350Ma期间保持同一连接方式.
A detailed palaeomagnetic study was carried out on the magenta shaly dolomite samples collected from the Jixian-Yangzhuang Formation (~ 1350 Ma) in the Jixian section of Jixian section, and two residual magnetic components were successfully separated. The low-temperature component A, in the geographic coordinate system, The direction of the magnetic field is close and is interpreted as a component of remanent magnetization. The high temperature stable remanent component B can pass the fold inversion test at the 99% confidence level through the fold test (Middle-Late Jurassic fold times) and 95% confidence level. Experiments show that the magnetic minerals are hematite, the average direction of which is D / I = 77.6 ° /? 24.3 ° (κ = 5.4, α95 = 18.3 °) before the structure correction and D / I = 72.2 ° after correction /11.5θ(κ=24.6,α95=7.9°,N=15), which is interpreted as primary remanence. The corresponding apparent magnetic pole position is (17.3 ° N, 214.5 ° E, dp / dm = 4.1 ° / 8.0 °) .The fitting results of the existing high-quality paleomagnetism poles show that the North China platform, Laurentia, Baltica and Siberia continent maintain the same connection mode in 1800 ~ 1350Ma.