Informace o publikaci
Magnetic record of inundation deposits along Mexican Pacific coast
| Autoři | |
|---|---|
| Rok publikování | 2016 |
| Druh | Konferenční abstrakty |
| Fakulta / Pracoviště MU | |
| Citace | |
| Popis | Earthquakes along active continental margins and submarine landslides can produce tsunami along the coastline around the globe. The study of the tsunami sediments is even more complicated by occasional storms that can produce an inundation and leave sedimentary deposits as well. Nevertheless, both tsunamis and storms put in risk coastal communities worldwide. Therefore, understanding of such processes is crucial for the hazard analysis in the coastal areas. Recently, it has been shown that the variability in magnetic properties can be significant and any treatment without statistical evaluation may give random results (Černý et al., 2016). Therefore, it is important to choose proper methodology of sampling due to natural variability of the sampled environment. In case of sediments, not only the variability can affect the results but also mechanical properties of the sediment. For that reason, it is always better to take some control samples. The most recent results of inundation deposit studies also show that proportional study of Ti and Fe in titanomagnetite can help to indicate its source (Černý et al., 2016). It applies especially for volcanic material as original source containing finer grains of titanomagnetite. The wide range of Curie temperatures, where a gradual drop of magnetic susceptibility followed by a sharp decrease can be observed, is typical for diffusive fractionation in such volcanic material (Zhou et al., 2000). It has been shown that some inundation deposits on the Mexican Pacific coast contain titanomagnetite with similar proportion of Ti and Fe as some tephra samples produced by active volcanoes in Mexico. In concluding, it points out that the study of thermomagnetic curves can be considered also as a useful tool to indicate the source of titanomagnetite, especially if its origin is related to volcanic rocks. |