The physical mechanisms of geomagnetic field recording in sediments

沉积作用和海底扩张这两个大规模的自然系统不断地记录和存档着变化的地磁场。沉积古地磁记录具有上级时间分辨率，但其古磁场信息并不明确。许多地质因素-沉积速率、磁性载体性质、基质成分、压实速率、宏观和微观环境-控制磁性颗粒的流动性、排列和固定。它们过滤、偏置、调制或随机化剩磁采集过程，从而产生古磁场记录。具有典型的低场强的反射截面尤其受到影响。这些信号变形可以识别和恢复，如果记录机制，其控制和滤波器的特性是更好地了解。对更详细的古地磁场数据的科学探索，使得对新的磁层学信号分析和验证技术的需求日益增长。野外和气候引起的信号成分的分离、古强度记录的多因素校准和时间平均锁定过程的反褶积越来越重要，但尚未解决的任务是，提出了几个新的实验和调查，以检测和量化沉积剩磁采集的微观机制，并发展经验、统计和分析模型。将在自然沉积的海洋表层沉积物柱上研究由布朗运动、压实、孔隙水流、生物扰动、微体化石分解、粘附力和毛细力、磁相互作用、微构造和地震活动引起的磁性粒子活化，并通过多芯取样进行探测。将使用SQUID和MPMS技术（如适用）在数小时至数月的延长时间内对弱环境场中的磁性粒子弛豫（作为各种受控治疗的函数）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.