The physical mechanisms of geomagnetic field recording in sediments

沉积和海底扩张这两个大尺度自然系统，不断记录和记录着不断变化的地磁场。沉积古地磁记录具有较高的时间分辨率，但其古场信息并不明确。许多地质因素--沉积速率、磁性载体特性、基质组成、压实率、宏观和微观环境--控制着磁性颗粒的流动性、排列和固定。它们对剩磁采集过程进行过滤、偏置、调制或随机化，从而得到古田记录。具有典型低场强的反转部分尤其受到影响。如果更好地了解记录机制、其控制和滤波特性，则可以识别和恢复这些信号变形。对更详细的古磁场数据的科学探索创造了对磁层析中新的信号分析和验证技术的日益增长的需求。场致信号分量和气候诱发信号分量的分离、古强度记录的多因素标定和时间平均锁定过程的反褶积是日益重要但尚未解决的任务。为了探测和量化沉积剩磁获取的微观机制，并建立经验、统计和分析模型，提出了几项新的实验和研究。在多岩心探测的自然沉积海洋表层沉积物柱上，研究了布朗运动、压实作用、孔隙水流、生物扰动、微化石解体、粘附力和毛细管力、磁相互作用、微构造和地震活动对磁粒子的激活作用。使用SQUID和MPMS(如果有的话)技术，将在几个小时到几个月的更长时间内使用SQUID和MPMS技术对作为各种受控处理功能的弱环境场中的磁粒子松弛进行磁性监测。将测试显微镜方法是否适用于可视化磁粉分布。

Two large-scale natural systems, sedimentation and sea floor spreading, continuously record and archive the changing geomagnetic field. Sedimentary paleomagnetic records attain superior temporal resolution, but their paleofield information is not unambiguous. Numerous geological factors - sedimentation rate, magnetic carrier properties, matrix composition, compac- tion rate, macro- and micro-environment - control mobility, alignment and fixation of magnetic particles. They filter, bias, modulate or randomize the remanence aquisition process and thus the resulting paleofield records. Reversal sections with their typically low field intensities are particularly affected. These signal deformations could be identified and recovered, if the recording mechanism, its controls and filter characteristics were better known. The scientific quest for ever more detailed paleofield data creates a growing need for new signal analysis and validation techniques in magnetostrati- graphy. Separation of field and climate induced signal com- ponents, multi-factorial calibration of paleointensity records and deconvolution of the time averaging lock-in process are increasingly important, yet unresolved tasks.Several new experiments and investigations are proposed to detect and quantify the micro-scale mechanisms of sedimentary remanence acquisition and to develop empirical, statistical and analytical models. Magnetic particle activation by Brownian motion, compaction, pore water flow, bioturbation, microfossil desintegration, adhesive and capillary forces, magnetic interaction, microtectonics and seismicity will be studied on naturally deposited marine surface sediment columns probed by multi-coring. Magnetic particle relaxation in weak ambient fields as a function of various controlled treatments will be magnetically monitored over extended periods from hours to months using SQUID and, if available, MPMS technology. Microscopic methods will be tested for their suitability to visualize magnetic particle distribution.