Basic Study of Paleoceanographic Reconstruction by Marine Ferro-manganese Crusts.

覆盖在露头岩石上的海相氧化锰铁沉淀物被认为是一种可能的长期古海洋学指标，以及未来的矿产资源，但基于精细定年和物理化学描述的研究很少。我们试图对分布在西太平洋海底的氢成因锰铁地壳进行微地层描述。我们发现一些位置相对较远的地壳的微地层具有较好的相关性，这表明在整个地质时代中，底部和中间水的横向影响是广泛的。相比之下，在不同深度的紧密位置之间，地壳的地层学差异很大。锰铁地壳的精细定年是海洋地质科学的重要领域之一。我们将古地磁反转模式与铍-10放射性化学定年和可能的巧合进行了精细的比较，证明这是另一种可靠的测年工具。我们准备利用超导磁力计（SQUID）分析精细抛光的地壳，以确定780,000年（计划于2005年6月在CALTEC）的确切磁极反转点。此外，我们还研究了氢化结壳的热退磁过程，获得了结壳磁性载体矿物的重要信息。未来，我们将继续研究这一课题，以确保磁地层学和过去海洋地质环境重建的可靠性。

Marine ferromanganese oxide precipitates covering the rock outcrops are regarded as a possible long-range paleoceanographic indicator, as well as future mineral resources, but little study has been done based on fine-scale dating and physical and chemical description. We attempted the microstratigrahic description of hydrogenetic ferromanganese crusts dispersed over the western Pacific ocean floors. We found fairly good correlation of the microstratigraphy of some crusts remotely located each other, which indicates the lateral wide influence of bottom and intermediate waters through the geologic time. By contrast, the stratigraphy is much different in the crusts between the close locations at different depths.The fine-scale age dating of ferromanganese crusts is one of the most important marine geological science fields. We compared fine the paleomagnetic reversal patterns and Berilium-10 radiochemical dating and possible coincidence, which is proved to be another reliable tool for dating. We are ready to analyze the finely polished crusts using the Super-conductor magnetometer (SQUID) to determine the exact point of magnetic reversal at 780000yr (planned at CALTEC on June 2005). Furthermore, we examined the thermal demagnetization process of the hydrogentic crusts and obtained important information about the carrier mineral of the magnetism of the crusts.In future, we continue to study this topic to ensure the reliability of magnetic stratigraphy and reconstruction of past oceanographic and geological environments.