Occurrence of small to moderate magnitude earthquakes in Kachchh intraplate zone: A special emphasis to the 2020 Bhachau earthquake
Since the 2001 Mw 7.7 Bhuj earthquake in Gujarat, western India, a number of small-to-moderate earthquakes have occurred to the east of the Bhuj rupture, near the town of Bhachau. In this paper, we present an overview of seismic monitoring in the region, and analysis of a Mw 5.3 earthquake that occu...
| Main Authors: | , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Elsevier
2022-06-01
|
| Series: | Journal of Asian Earth Sciences: X |
| Subjects: | |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S259005602200010X |
| _version_ | 1818469100470403072 |
|---|---|
| author | Pallabee Choudhury Charu Kamra Santosh Kumar Ketan Singha Roy K. Madhusudhana Rao Sumer Chopra M. Ravi Kumar |
| author_facet | Pallabee Choudhury Charu Kamra Santosh Kumar Ketan Singha Roy K. Madhusudhana Rao Sumer Chopra M. Ravi Kumar |
| author_sort | Pallabee Choudhury |
| collection | DOAJ |
| description | Since the 2001 Mw 7.7 Bhuj earthquake in Gujarat, western India, a number of small-to-moderate earthquakes have occurred to the east of the Bhuj rupture, near the town of Bhachau. In this paper, we present an overview of seismic monitoring in the region, and analysis of a Mw 5.3 earthquake that occurred near Bhachau on 14 June 2020. Moment tensor analysis of regional broadband data reveals a reverse mechanism with a small strike-slip component, generally similar to that of the 2001 Bhuj earthquake. A total of 20 aftershocks with magnitudes ranging from 2.0 to 4.6 were recorded within the first 10 days of the sequence. After that, this region recorded 129 tremors of magnitude 2.0–4.2 until June 2021. We conclude that this sequence occurred on the South Wagad fault (SWF)-Kachchh Mainland fault (KMF) system, a complex zone comprising many separate mapped faults. A recent analysis of Global Positioning System (GPS) data reveals that the area is under broad compressive stress, with a maximum strain of 5 nano-strain/year. The occurrence of the 2020 Bhachau earthquake underscores concerns for continuing seismic hazard in the region. |
| first_indexed | 2024-04-13T21:19:43Z |
| format | Article |
| id | doaj.art-a8d1904ef5c44203a6b86005778f36fa |
| institution | Directory Open Access Journal |
| issn | 2590-0560 |
| language | English |
| last_indexed | 2024-04-13T21:19:43Z |
| publishDate | 2022-06-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Journal of Asian Earth Sciences: X |
| spelling | doaj.art-a8d1904ef5c44203a6b86005778f36fa2022-12-22T02:29:32ZengElsevierJournal of Asian Earth Sciences: X2590-05602022-06-017100089Occurrence of small to moderate magnitude earthquakes in Kachchh intraplate zone: A special emphasis to the 2020 Bhachau earthquakePallabee Choudhury0Charu Kamra1Santosh Kumar2Ketan Singha Roy3K. Madhusudhana Rao4Sumer Chopra5M. Ravi Kumar6Institute of Seismological Research, Raisan, Gandhinagar, Gujarat 382009, India; Corresponding author.Institute of Seismological Research, Raisan, Gandhinagar, Gujarat 382009, IndiaInstitute of Seismological Research, Raisan, Gandhinagar, Gujarat 382009, IndiaInstitute of Seismological Research, Raisan, Gandhinagar, Gujarat 382009, IndiaInstitute of Seismological Research, Raisan, Gandhinagar, Gujarat 382009, IndiaInstitute of Seismological Research, Raisan, Gandhinagar, Gujarat 382009, IndiaCSIR-National Geophysical Research Institute, Hyderabad, Telengana 500007, IndiaSince the 2001 Mw 7.7 Bhuj earthquake in Gujarat, western India, a number of small-to-moderate earthquakes have occurred to the east of the Bhuj rupture, near the town of Bhachau. In this paper, we present an overview of seismic monitoring in the region, and analysis of a Mw 5.3 earthquake that occurred near Bhachau on 14 June 2020. Moment tensor analysis of regional broadband data reveals a reverse mechanism with a small strike-slip component, generally similar to that of the 2001 Bhuj earthquake. A total of 20 aftershocks with magnitudes ranging from 2.0 to 4.6 were recorded within the first 10 days of the sequence. After that, this region recorded 129 tremors of magnitude 2.0–4.2 until June 2021. We conclude that this sequence occurred on the South Wagad fault (SWF)-Kachchh Mainland fault (KMF) system, a complex zone comprising many separate mapped faults. A recent analysis of Global Positioning System (GPS) data reveals that the area is under broad compressive stress, with a maximum strain of 5 nano-strain/year. The occurrence of the 2020 Bhachau earthquake underscores concerns for continuing seismic hazard in the region.http://www.sciencedirect.com/science/article/pii/S259005602200010XKachchhMoment tensor solutionSouth Wagad fault systemBhuj earthquakeBhachau earthquake |
| spellingShingle | Pallabee Choudhury Charu Kamra Santosh Kumar Ketan Singha Roy K. Madhusudhana Rao Sumer Chopra M. Ravi Kumar Occurrence of small to moderate magnitude earthquakes in Kachchh intraplate zone: A special emphasis to the 2020 Bhachau earthquake Journal of Asian Earth Sciences: X Kachchh Moment tensor solution South Wagad fault system Bhuj earthquake Bhachau earthquake |
| title | Occurrence of small to moderate magnitude earthquakes in Kachchh intraplate zone: A special emphasis to the 2020 Bhachau earthquake |
| title_full | Occurrence of small to moderate magnitude earthquakes in Kachchh intraplate zone: A special emphasis to the 2020 Bhachau earthquake |
| title_fullStr | Occurrence of small to moderate magnitude earthquakes in Kachchh intraplate zone: A special emphasis to the 2020 Bhachau earthquake |
| title_full_unstemmed | Occurrence of small to moderate magnitude earthquakes in Kachchh intraplate zone: A special emphasis to the 2020 Bhachau earthquake |
| title_short | Occurrence of small to moderate magnitude earthquakes in Kachchh intraplate zone: A special emphasis to the 2020 Bhachau earthquake |
| title_sort | occurrence of small to moderate magnitude earthquakes in kachchh intraplate zone a special emphasis to the 2020 bhachau earthquake |
| topic | Kachchh Moment tensor solution South Wagad fault system Bhuj earthquake Bhachau earthquake |
| url | http://www.sciencedirect.com/science/article/pii/S259005602200010X |
| work_keys_str_mv | AT pallabeechoudhury occurrenceofsmalltomoderatemagnitudeearthquakesinkachchhintraplatezoneaspecialemphasistothe2020bhachauearthquake AT charukamra occurrenceofsmalltomoderatemagnitudeearthquakesinkachchhintraplatezoneaspecialemphasistothe2020bhachauearthquake AT santoshkumar occurrenceofsmalltomoderatemagnitudeearthquakesinkachchhintraplatezoneaspecialemphasistothe2020bhachauearthquake AT ketansingharoy occurrenceofsmalltomoderatemagnitudeearthquakesinkachchhintraplatezoneaspecialemphasistothe2020bhachauearthquake AT kmadhusudhanarao occurrenceofsmalltomoderatemagnitudeearthquakesinkachchhintraplatezoneaspecialemphasistothe2020bhachauearthquake AT sumerchopra occurrenceofsmalltomoderatemagnitudeearthquakesinkachchhintraplatezoneaspecialemphasistothe2020bhachauearthquake AT mravikumar occurrenceofsmalltomoderatemagnitudeearthquakesinkachchhintraplatezoneaspecialemphasistothe2020bhachauearthquake |