Simulating seismic liquefaction: A laboratory approach to identifying new paleoseismic markers

Identifying reliable indicators of past seismic activity in sedimentary archives is crucial for advancing paleoseismology and understanding earthquake-driven sediment deformation. However, micro-scale mineralogical features have remained underexplored. In this study, we present the results of a 12-month-long experimental program simulating earthquake-induced liquefaction using fine-grained siliciclastic sediments and varying chemical conditions.

A total of 108 samples were incubated under reducing conditions in plexiglass cylinders with either Fe(II) sulfate or FeO(OH) additions. Seismic shaking simulations were conducted at intervals using a controlled vibration table calibrated to reproduce magnitude 3.5 equivalents. Micromorphological and mineralogical analyses (SEM, EDS, and Raman spectroscopy) revealed the consistent formation of core–rim structures (CRS) across all experimental variants, regardless of water chemistry or iron source. These features were absent in control samples not subjected to shaking, as well as in naturally deformed sediments of non-seismic origin (e.g., storm-induced structures).

These results suggest that seismic energy may facilitate fluid redistribution, mineral precipitation, and the formation of distinctive microscale deformation features. To ground experimental findings, we compared them to field samples where CRS and sideritic textures were also documented within known SSDS. In contrast, similar structures were absent in sediment samples with storm events and rapid loading genesis.

This integrated field–experimental approach offers a novel framework for identifying microseismic indicators in the sedimentary record. While more research across diverse environments is needed, CRS may represent a promising addition to the paleoseismological toolbox, particularly for low-magnitude or poorly preserved events.