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在Jacobsville组的257块样上(37个采样点)进行了化学的、热的和交变磁场(AF)的检验指出,磁化是在很长的时间内渐渐获得的。可划分出三个磁化阶段,并能用化学方法顺序地分离出来。热的(到达675℃)和交变磁场(到290mT)的检验不能区别和分离最初的两个磁化阶段。该项结果与以前曾提出过的三阶段磁化模式是一致的,并再次证明在红层研究中进行化学实验的必要性,用化学方法分离出的早期剩余磁性证明Jacobsville组是上基韦诺时期的(≌-1100百万年)。从三个地区得到了极位置,即:苏圣马里(SSM),175°E,12°N;马克特(M)182°E,03°S;基韦诺半岛(KP),180°E,10°S。说明(SSM)沉积岩比KP的岩石要老。在杰克布斯维耳(Jacobsville)地区一个5.3米地层剖面上,做了详细的研究(九个采样点,平均磁极位置在190°E,16°S),显示出很有意思的视极移动和至少出现一个磁场的倒转。与北美有关的极移动方向指向南。向量分析显示出,在中期和后期的剩余磁性获得期间视磁极开始向北移动;到磁化作用结束时,磁极到达高纬度(307°E,72°N)。Jacobsville组的结果和其他高纬度极的解释要求修改哈德林时期的视移轨迹。提议的轨迹是将曲线延伸到了南半球(-1100—-950百万年),而后约略顺着一个大圆轨迹(哈德林轨迹)从赤道附近的160°E到现在的地理北极,再向下340°E的赤道(-670百万年)。有争议的格伦维耳极能容易地加入到那个曲线中,证明格伦维耳省总是Laurentia的主要部分的假说。具有大的磁极移动的哈德林轨迹(在300百万年移动180°)是非常有用的地层工具,它能极方便地利用于晚前寒武纪岩石单位的全球性对比。
Chemical, thermal and alternating magnetic field (AF) tests on 257 samples (37 sampling points) of the Jacobsville group indicate that magnetization is progressively obtained over a long period of time. Can be divided into three stages of magnetization, and can be chemically separated sequentially. Examination of the hot (up to 675 ° C) and alternating magnetic field (up to 290 mT) can not distinguish and separate the first two phases of magnetization. This result is consistent with the three-stage magnetization model previously proposed and again demonstrates the necessity of conducting chemical experiments in the red layer study. The chemical composition of the early residual magnetism evidenced that the Jacobsville group was a member of the Upper Guijuano Period (≌-1100 million years). The polar position is obtained from three areas: SSM, 175 ° E, 12 ° N; Mark 182 ° E, 03 ° S; Kivu Peninsula (KP), 180 ° E , 10 ° S. Sedimentary rocks (SSM) are older than KP rocks. A detailed study of a 5.3-m section in the Jacobsville region (nine sampling points with average pole positions at 190 ° E, 16 ° S) shows a very interesting translation of the apparent pole and At least one reversal of the magnetic field occurs. The direction of the North American-related pole-shift points south. Vector analysis shows that the apparent magnetic pole begins to move northward during the mid and late residual magnetic acquisitions; by the end of magnetization, the poles reach high latitudes (307 ° E, 72 ° N). The results of the Jacobsville Formation and other interpretations at the high latitudes required the modification of the visual displacement trajectory during the Hadrian period. The proposed trajectory is to extend the curve to the southern hemisphere (-1100 to 950 million years) and then roughly a hundred years from the 160 ° E near the equator to the present-day geographic North Pole along a large circular trajectory (Hadrian’s orbit) ° E of the equator (-670 million years). The controversial Glenn Wheeler can easily join that curve, proving the hypothesis that Grenville is always a major part of Laurentia. The Hadlin trajectories with large pole shifts (180 ° for 300 million years) are very useful stratigraphic tools that make it extremely easy to exploit the global contrast of late Precambrian rock units.