Co- and Postseismic Deformation of the 2020 Mw 6.3 Nima (Tibet, China) Earthquake Revealed by InSAR Observations
On 22 July 2020, an Mw 6.3 earthquake occurred in Nima County, central Qinghai-Tibet Plateau, China. We used the synthetic aperture radar interferometry (InSAR) technique with Sentinel-1 images to retrieve the line of sight (LOS) coseismic deformation fields which indicate that the maximum surface d...
| Main Authors: | , , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2022-10-01
|
| Series: | Remote Sensing |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2072-4292/14/21/5390 |
| _version_ | 1797466590691721216 |
|---|---|
| author | Miaomiao Zhang Zhenhong Li Chen Yu Zhenjiang Liu Xuesong Zhang Jiatong Wang Jing Yang Bingquan Han Jianbing Peng |
| author_facet | Miaomiao Zhang Zhenhong Li Chen Yu Zhenjiang Liu Xuesong Zhang Jiatong Wang Jing Yang Bingquan Han Jianbing Peng |
| author_sort | Miaomiao Zhang |
| collection | DOAJ |
| description | On 22 July 2020, an Mw 6.3 earthquake occurred in Nima County, central Qinghai-Tibet Plateau, China. We used the synthetic aperture radar interferometry (InSAR) technique with Sentinel-1 images to retrieve the line of sight (LOS) coseismic deformation fields which indicate that the maximum surface displacement reached ~30 cm. We then processed a series of interferograms spanning one year after the Nima earthquake with the Small Baseline Subset Interferometric SAR (SBAS-InSAR) technique. The maximum cumulative postseismic LOS surface displacement reached ~8 cm and approximately followed a logarithmic function over time. The inversion of the fault geometry and co- and afterslip distribution shows that the epicenter location was (33.18°N, 86.88°E) at a depth of 7.4 km, and the causative fault had an N29.1°E strike and 50.2° dip. The most coseismic slip was concentrated at depths between 3 to 12 km with a peak value of 2.0 m at 7.4 km, whilst most afterslips were concentrated at depths between 0 to 12 km with a peak value of 0.2 m at 5 km. The postseismic moment energy was about 5.04 × 10<sup>17</sup> N∙m 308 days after the event, which was approximately 13.8% of the coseismic moment energy. By analyzing the contribution of afterslip and poroelastic rebound to postseismic deformation, it was concluded that afterslip was the main early postseismic deformation mechanism. Future attention should be paid to the northern segment of the West Yibug Caka fault and East Yibug Caka fault. |
| first_indexed | 2024-03-09T18:41:55Z |
| format | Article |
| id | doaj.art-4bf5d701e44146298c2f49c998fdbab2 |
| institution | Directory Open Access Journal |
| issn | 2072-4292 |
| language | English |
| last_indexed | 2024-03-09T18:41:55Z |
| publishDate | 2022-10-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Remote Sensing |
| spelling | doaj.art-4bf5d701e44146298c2f49c998fdbab22023-11-24T06:38:13ZengMDPI AGRemote Sensing2072-42922022-10-011421539010.3390/rs14215390Co- and Postseismic Deformation of the 2020 Mw 6.3 Nima (Tibet, China) Earthquake Revealed by InSAR ObservationsMiaomiao Zhang0Zhenhong Li1Chen Yu2Zhenjiang Liu3Xuesong Zhang4Jiatong Wang5Jing Yang6Bingquan Han7Jianbing Peng8College of Geological Engineering and Geomatics, Chang’an University, Xi’an 710054, ChinaCollege of Geological Engineering and Geomatics, Chang’an University, Xi’an 710054, ChinaCollege of Geological Engineering and Geomatics, Chang’an University, Xi’an 710054, ChinaCollege of Geological Engineering and Geomatics, Chang’an University, Xi’an 710054, ChinaCollege of Geological Engineering and Geomatics, Chang’an University, Xi’an 710054, ChinaCollege of Geological Engineering and Geomatics, Chang’an University, Xi’an 710054, ChinaCollege of Geological Engineering and Geomatics, Chang’an University, Xi’an 710054, ChinaCollege of Geological Engineering and Geomatics, Chang’an University, Xi’an 710054, ChinaCollege of Geological Engineering and Geomatics, Chang’an University, Xi’an 710054, ChinaOn 22 July 2020, an Mw 6.3 earthquake occurred in Nima County, central Qinghai-Tibet Plateau, China. We used the synthetic aperture radar interferometry (InSAR) technique with Sentinel-1 images to retrieve the line of sight (LOS) coseismic deformation fields which indicate that the maximum surface displacement reached ~30 cm. We then processed a series of interferograms spanning one year after the Nima earthquake with the Small Baseline Subset Interferometric SAR (SBAS-InSAR) technique. The maximum cumulative postseismic LOS surface displacement reached ~8 cm and approximately followed a logarithmic function over time. The inversion of the fault geometry and co- and afterslip distribution shows that the epicenter location was (33.18°N, 86.88°E) at a depth of 7.4 km, and the causative fault had an N29.1°E strike and 50.2° dip. The most coseismic slip was concentrated at depths between 3 to 12 km with a peak value of 2.0 m at 7.4 km, whilst most afterslips were concentrated at depths between 0 to 12 km with a peak value of 0.2 m at 5 km. The postseismic moment energy was about 5.04 × 10<sup>17</sup> N∙m 308 days after the event, which was approximately 13.8% of the coseismic moment energy. By analyzing the contribution of afterslip and poroelastic rebound to postseismic deformation, it was concluded that afterslip was the main early postseismic deformation mechanism. Future attention should be paid to the northern segment of the West Yibug Caka fault and East Yibug Caka fault.https://www.mdpi.com/2072-4292/14/21/5390Nima earthquakecoseismic deformationgeodetic inversionpostseismic deformationafterslip |
| spellingShingle | Miaomiao Zhang Zhenhong Li Chen Yu Zhenjiang Liu Xuesong Zhang Jiatong Wang Jing Yang Bingquan Han Jianbing Peng Co- and Postseismic Deformation of the 2020 Mw 6.3 Nima (Tibet, China) Earthquake Revealed by InSAR Observations Remote Sensing Nima earthquake coseismic deformation geodetic inversion postseismic deformation afterslip |
| title | Co- and Postseismic Deformation of the 2020 Mw 6.3 Nima (Tibet, China) Earthquake Revealed by InSAR Observations |
| title_full | Co- and Postseismic Deformation of the 2020 Mw 6.3 Nima (Tibet, China) Earthquake Revealed by InSAR Observations |
| title_fullStr | Co- and Postseismic Deformation of the 2020 Mw 6.3 Nima (Tibet, China) Earthquake Revealed by InSAR Observations |
| title_full_unstemmed | Co- and Postseismic Deformation of the 2020 Mw 6.3 Nima (Tibet, China) Earthquake Revealed by InSAR Observations |
| title_short | Co- and Postseismic Deformation of the 2020 Mw 6.3 Nima (Tibet, China) Earthquake Revealed by InSAR Observations |
| title_sort | co and postseismic deformation of the 2020 mw 6 3 nima tibet china earthquake revealed by insar observations |
| topic | Nima earthquake coseismic deformation geodetic inversion postseismic deformation afterslip |
| url | https://www.mdpi.com/2072-4292/14/21/5390 |
| work_keys_str_mv | AT miaomiaozhang coandpostseismicdeformationofthe2020mw63nimatibetchinaearthquakerevealedbyinsarobservations AT zhenhongli coandpostseismicdeformationofthe2020mw63nimatibetchinaearthquakerevealedbyinsarobservations AT chenyu coandpostseismicdeformationofthe2020mw63nimatibetchinaearthquakerevealedbyinsarobservations AT zhenjiangliu coandpostseismicdeformationofthe2020mw63nimatibetchinaearthquakerevealedbyinsarobservations AT xuesongzhang coandpostseismicdeformationofthe2020mw63nimatibetchinaearthquakerevealedbyinsarobservations AT jiatongwang coandpostseismicdeformationofthe2020mw63nimatibetchinaearthquakerevealedbyinsarobservations AT jingyang coandpostseismicdeformationofthe2020mw63nimatibetchinaearthquakerevealedbyinsarobservations AT bingquanhan coandpostseismicdeformationofthe2020mw63nimatibetchinaearthquakerevealedbyinsarobservations AT jianbingpeng coandpostseismicdeformationofthe2020mw63nimatibetchinaearthquakerevealedbyinsarobservations |