Fault parameters of the Tabas-e-Golshan earthquake, September 16, 1978 (eastern Iran), based on macroseismic observations, with locations for dating to improve the dataset

Abstract

Estimating the macroseismic parameters of earthquakes such as location, magnitude, and fault orientation can be helpful to complete the earthquake catalogs, especially on historical ones or the ones whose parameters were estimated with low accuracy. This study aims to estimate the macroseismic parameters of Tabas earthquake (1978.09.16) using its reported descriptions, Macroseismic Data Points (MDPs). MDPs include any descriptions of earthquake effects on building damages and environmental effects of each location affected by the earthquake. Macroseismic dataset of Tabas earthquake is collected from different documents. Thus, this dataset is used to estimate the macroseismic parameters of this earthquake: macroseismic location, magnitude, intensity, and source parameters. Results estimate the macroseismic epicenter of this earthquake at 33.49°N–56.94°E with the moment magnitude, Mw, 7.1 and the maximum macroseismic intensity value XI in both EMS and ESI intensity scales. Its estimated source orientation is consistent to Tabas fault system in the direction NNW-SSE with the strike, length, and width value of the source in 166.8°, 55.8 ± 7.5 km, and 18.2 ± 1.4 km, respectively. Moreover, for future studies, the locations near Khosro Abad, close to the macroseismic epicenter of this earthquake, are suggested for the next field studies, sampling the sediments related to the past evidences and dating them.