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This data was gathered during the Geotechnical Extreme Events Reconnaissance (GEER) efforts following the February 6, 2023, Kahramanmaraş earthquake sequence. This dataset is comprised of terrestrial lidar scan point clouds that aim to capture liquefaction-induced building settlement, building-ground interactions, and ground deformations. The objective of the reconnaissance efforts was to capture perishable data on ground failures and liquefaction-induced infrastructure damage due to these earthquakes. Reconnaissance was performed from March 27 to April 1, 2023 in and around İskenderun, Hatay; Gölbaşı, Adıyaman; and Antakya, Hatay. Lidar scans were performed in İskenderun and Gölbaşı at selected liquefaction building sites. The reconnaissance sites were selected as those where there was evidence of liquefaction (e.g., ejecta) and liquefaction-induced building settlements, as well as building-ground interactions, and site access. The processed lidar data are included as .las point cloud files; raw data are included as .fls files. The point cloud data may be viewed and analyzed in point cloud analysis software, including the opensource software CloudCompare. Additional images of the surveyed buildings are included for reference. An explanation of the data types and structure is found in the README.pdf file. These data may be used to investigate earthquake liquefaction-induced building settlements, building-ground interactions, and liquefaction-induced ground deformations. These data will be of use and interest to engineers and researchers working in the area of liquefaction ground failures and building-ground interactions. Additional information and data from this reconnaissance are available in the GEER reports, which are referenced in the "Related Works" section.
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Rapid Building Damage Estimates From the M7.8 Turkey Earthquake Sequence via Causality-Informed Bayesian Inference From Satellite Imagery
On February 6, 2023, a major earthquake of 7.8 magnitude and its aftershocks caused widespread destruction in Turkey and Syria, causing more than 55,000 deaths, displacing 3 million people in Turkey and 2.9 million in Syria, and destroying or damaging at least 230,000 buildings. Our research presents detailed city-scale maps of landslides, liquefaction, and building damage from this earthquake, utilizing a novel variational causal Bayesian network. This network integrates InSAR-derived change detection with new empirical ground failure models and building footprints, enabling us to (1) rapidly estimate large-scale building damage, landslides, and liquefaction from remote sensing data, (2) jointly attribute building damage to landslides, liquefaction, and shaking, (3) improve regional landslide and liquefaction predictions impacting infrastructure, and (4) simultaneously identify damage degrees in thousands of buildings. For city-scale, building-by-building damage assessments, we use building footprints and satellite imagery with a spatial resolution of approximately 30 meters. This allows us to achieve a high resolution in damage assessment, both in timeliness and scale, enabling damage classification at the individual building level within days of the earthquake. Our findings detail the extent of building damage, including collapses, in Hatay, Osmaniye, Adıyaman, Gaziantep, and Kahramanmaras. We classified building damages into five categories: no damage, slight, moderate, partial collapse, and collapse. We evaluated damage estimates against preliminary ground-truth data reported by the civil authorities. Our results demonstrate the accuracy of our classification system, as evidenced by the area under the curve (AUC) scores on the receiver operating characteristic (ROC) curve, which ranged from 0.9588 to 0.9931 across different damage categories and regions. Specifically, our model achieved an AUC of 0.9931 for collapsed buildings in the Hatay/Osmaniye area, indicating a 99.31% probability that the model will rank a randomly chosen collapsed building higher than a randomly chosen non-collapsed building. These accurate, building-specific damage estimates, with greater than 95% classification accuracy across all categories, are crucial for disaster response and can aid agencies in effectively allocating resources and coordinating efforts during disaster recovery.
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- PAR ID:
- 10556010
- Publisher / Repository:
- SAGE Publications
- Date Published:
- Journal Name:
- Earthquake Spectra
- Volume:
- 41
- Issue:
- 1
- ISSN:
- 8755-2930
- Format(s):
- Medium: X Size: p. 5-33
- Size(s):
- p. 5-33
- Sponsoring Org:
- National Science Foundation
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This data was gathered during the Geotechnical Extreme Events Reconnaissance (GEER) efforts following the February 6, 2023, Kahramanmaraş earthquake sequence. This dataset is comprised of terrestrial lidar scan point clouds that aim to capture liquefaction-induced building settlement, building-ground interactions, and ground deformations. The objective of the reconnaissance efforts was to capture perishable data on ground failures and liquefaction-induced infrastructure damage due to these earthquakes. Reconnaissance was performed from March 27 to April 1, 2023 in and around İskenderun, Hatay; Gölbaşı, Adıyaman; and Antakya, Hatay. Lidar scans were performed in İskenderun and Gölbaşı at selected liquefaction building sites. The reconnaissance sites were selected as those where there was evidence of liquefaction (e.g., ejecta) and liquefaction-induced building settlements, as well as building-ground interactions, and site access. The processed lidar data are included as .las point cloud files; raw data are included as .fls files. The point cloud data may be viewed and analyzed in point cloud analysis software, including the opensource software CloudCompare. Additional images of the surveyed buildings are included for reference. An explanation of the data types and structure is found in the README.pdf file. These data may be used to investigate earthquake liquefaction-induced building settlements, building-ground interactions, and liquefaction-induced ground deformations. These data will be of use and interest to engineers and researchers working in the area of liquefaction ground failures and building-ground interactions. Additional information and data from this reconnaissance are available in the GEER reports, which are referenced in the "Related Works" section.more » « less
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