Figure 1: Magnetization acquisition of sediment in nature and in the laboratory. | Nature Communications

Figure 1: Magnetization acquisition of sediment in nature and in the laboratory.

From: Microbially assisted recording of the Earth’s magnetic field in sediment

Figure 1

(a) Schematic representation of natural processes affecting sedimentary magnetizations (modified from ref. 15). 1: Marine snow, 2: flocculation, 3: settling, 4: sediment resuspension, 5: non-local mixing, for example, by polychaete worms, 6: local (diffusive) sediment mixing leading to particle reorientation and 7: burial in the consolidating layer. (b) Schematic representation of sediment redeposition in five different time frames. A homogeneous sediment suspension settles in a magnetic field forming a clear sediment–water interface (dashed line) after some time. The same five particles are highlighted by black dots in each frame. A DRM is acquired by the alignment of magnetized particles in the ambient field during deposition (frames 1–4). This magnetization is stabilized by inter-particle forces developing at contact points (frames 3–4). Sediment mixing (arrow in frame 5) is responsible for particle realignment after deposition and generates a PDRM. Only local (diffusive) sediment mixing is produced in our experiments. (c) Height of the sediment–water interface (dots), for three redeposition experiments. The dashed line is a guide for the eye. A nearly stable interface is obtained within the first day.

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