Article Dans Une Revue Scientific Reports Année : 2023

Surface rupture and landscape response in the middle of the great Mw 8.3 1934 earthquake mesoseismal area: Khutti Khola site

Résumé

Large earthquakes breaking the frontal faults of the Himalayan thrust system produce surface ruptures, quickly altered due to the monsoon conditions. Therefore, the location and existence of the Mw8.3 1934 Bihar-Nepal surface ruptures remain vividly disputed. Even though, previous studies revealed remnants of this surface rupture at the western end of the devastated zone, ruptures extent remains undocumented in its central part. Evidence for recent earthquakes is revealed along the frontal thrust in this region. The Khutti Khola river cuts an 8 m-high fault scarp exposing Siwalik siltstone thrusted over recent alluvial deposits, with faults sealed by a colluvial wedge and undeformed alluvial sediments. Detrital charcoals radiocarbon dating reveals that the last event occurred between the seventeenth century and the post-bomb era, advocating for the 1934 earthquake as the most recent event. In the hanging wall, fluvial terraces associated with fault scarps were abandoned after a penultimate event that happened after the tenth century, a rupture we associate with the historic earthquake of 1255CE. Slips of 11-17 m and 14-22 m for the 1934 and 1255 earthquakes, respectively, compare well with the ~ 10-15 m slip deficit accumulated between the two earthquakes, suggesting that most of the deformation along the front is accommodated by surface-rupturing earthquakes.

Fichier principal
Vignette du fichier
s41598-023-30697-7.pdf (4.94 Mo) Télécharger le fichier
Origine Fichiers éditeurs autorisés sur une archive ouverte
Licence

Dates et versions

insu-04131492 , version 1 (16-06-2023)

Licence

Identifiants

Citer

Magali Riesner, Laurent Bollinger, Magali Rizza, Yann Klinger, Çaǧıl Karakaş, et al.. Surface rupture and landscape response in the middle of the great Mw 8.3 1934 earthquake mesoseismal area: Khutti Khola site. Scientific Reports, 2023, 13, 349, p. 11-22. ⟨10.1038/s41598-023-30697-7⟩. ⟨insu-04131492⟩
201 Consultations
198 Téléchargements

Altmetric

Partager

  • More