Mineral Identification of Sedimentary Deposits of the 2004 Tsunami on the Aceh Besar Coast, Indonesia

Abstract

Understanding tsunami deposit is quite important in order to understand the history of the tsunami and its process deeply. Nonetheless, most tsunami deposit studies only discussed the sediment grain characteristics, not the mineral contents in the deposits. Meanwhile, understanding the minerals in tsunami deposits is essential in order to understand the sediment composition deeply. Thus, we have utilized X-Ray Fluorescence and X-Ray Diffraction to study the sedimentary deposits of the 26 December 2004 Indian Ocean tsunami on the Aceh Besar coast, Indonesia. Our results showed that the sedimentary deposits of tsunami 2004 on the Aceh Besar coast contain 55% of SiO2, 19% of Fe2O3, 12% of Al2O3, 9% of CaO, 3% of K2O, and 2% of TiO2. The deposits are found to be crystalline with the average crystallite size of 678 Å. There is no heavy mineral found in the tsunami deposit from Aceh Besar coast. Our results revealed that the composition of mineral contained in the sedimentary deposits of tsunami 2004 on the Aceh Besar coast is the same as those from the volcanic ash.