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对西菲律宾海本哈姆高原的Ph05重力柱样沉积物进行了系统的岩石磁学和古地磁研究,结果表明载磁矿物主要为准单畴磁铁矿,磁性矿物的含量变化不大,表明该孔适合于古地磁场相对强度(RPI)重建.应用磁化率、非磁滞剩磁(ARM)和饱和等温剩磁(SIRM)归一化天然剩磁,从而得到RPI.为了进一步确定由3种方法得到的RPI的可靠性,运用P-T方法和交叉谱分析进行检验,发现应用ARM归一化得到的RPI与相关的气候参数相关性最小,因此认为应用ARM作为归一化参数得到的RPI最为可靠.基于RPI建立的年代模型与基于AMS14C测年数据以及通过有孔虫氧同位素曲线而建立的年代模型较为一致.文中得到的过去200ka以来的RPI与全球其他地区得到的相应曲线非常相似,其强度低值可以和Sint-200的谷值相对应,这种相似性证实了地球磁场强度变化的全球一致性.
Ph05 gravimetric column sediments from the Himburum plateau in Western Philippines were systematically studied by rock magnetism and paleomagnetism. The results show that the magnetotactic minerals are mainly quasi-single-domain magnetite with little change in the contents of magnetic minerals This well is suitable for RPI reconstruction, and RPI is obtained by normalizing the remanent magnetization using magnetic susceptibility, non-hysteresis remanence (ARM) and saturated isothermal remanence magnetism (SIRM) The reliability of RPI obtained by this method was tested by PT method and crossover spectrum analysis. It was found that the correlation between the RPI normalized by ARM and the related climate parameters was the smallest, and therefore the RPI with ARM as the normalization parameter was the most Reliable.The dating model based on RPI is consistent with the dating model based on AMS14C and the age model established by the foraminiferal oxygen isotope curve.The RPI obtained in the past 200ka is very similar to that obtained in other parts of the world, Low intensities correspond to the valleys of Sint-200, a similarity that confirms the global consistency of changes in the magnetic field strength of the Earth.