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Optimized volume models of earthquake-triggered landslides.

Xu C, Xu X, Shen L, Yao Q, Tan X, Kang W, Ma S, Wu X, Cai J, Gao M, Li K - Sci Rep (2016)

Bottom Line: The samples were used to fit the conventional landslide "volume-area" power law relationship and the 3 optimized models we proposed, respectively.Two data fitting methods, i.e. log-transformed-based linear and original data-based nonlinear least square, were employed to the 4 models.Results show that original data-based nonlinear least square combining with an optimized model considering length, width, height, lithology, slope, peak ground acceleration, and slope aspect shows the best performance.

View Article: PubMed Central - PubMed

Affiliation: Key Laboratory of Active Tectonics and Volcano, Institute of Geology, China Earthquake Administration, Beijing, 100029, China.

ABSTRACT
In this study, we proposed three optimized models for calculating the total volume of landslides triggered by the 2008 Wenchuan, China Mw 7.9 earthquake. First, we calculated the volume of each deposit of 1,415 landslides triggered by the quake based on pre- and post-quake DEMs in 20 m resolution. The samples were used to fit the conventional landslide "volume-area" power law relationship and the 3 optimized models we proposed, respectively. Two data fitting methods, i.e. log-transformed-based linear and original data-based nonlinear least square, were employed to the 4 models. Results show that original data-based nonlinear least square combining with an optimized model considering length, width, height, lithology, slope, peak ground acceleration, and slope aspect shows the best performance. This model was subsequently applied to the database of landslides triggered by the quake except for two largest ones with known volumes. It indicates that the total volume of the 196,007 landslides is about 1.2 × 10(10) m(3) in deposit materials and 1 × 10(10) m(3) in source areas, respectively. The result from the relationship of quake magnitude and entire landslide volume related to individual earthquake is much less than that from this study, which reminds us the necessity to update the power-law relationship.

No MeSH data available.


Related in: MedlinePlus

Distribution maps of landslides triggered by the 2008 Wenchuan earthquake and landslide volume samples.(A) Distribution of 197,481 landslides21. (B) Distribution of 25,580 individual landslides with area larger than 10,000 m2. (C) 1,415 landslide samples (denoted by polygons) on pre-quake DEM (20 m). (D) The samples (denoted by points) and areas without data on post-quake DEM (20 m). A1, the approximately distribution elliptical area of landslides larger than 110,000 km2; A2, the 44,000-km2 area with relatively higher landslide abundance; A3, the coverage area of pre- and post-quake DEMs. The colorful hillshade backgrounds on the panels A-D are from SRTM DEM23 (90 m) based on the ArcGIS 9.2 Platform (http://www.esri.com/apps/products). The pre- and post-quake grey DEMs on the panels C and D are from SPOT 5 stereoscopic pairs of images. All the four figures were also generated using the ArcGIS 9.2.
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f1: Distribution maps of landslides triggered by the 2008 Wenchuan earthquake and landslide volume samples.(A) Distribution of 197,481 landslides21. (B) Distribution of 25,580 individual landslides with area larger than 10,000 m2. (C) 1,415 landslide samples (denoted by polygons) on pre-quake DEM (20 m). (D) The samples (denoted by points) and areas without data on post-quake DEM (20 m). A1, the approximately distribution elliptical area of landslides larger than 110,000 km2; A2, the 44,000-km2 area with relatively higher landslide abundance; A3, the coverage area of pre- and post-quake DEMs. The colorful hillshade backgrounds on the panels A-D are from SRTM DEM23 (90 m) based on the ArcGIS 9.2 Platform (http://www.esri.com/apps/products). The pre- and post-quake grey DEMs on the panels C and D are from SPOT 5 stereoscopic pairs of images. All the four figures were also generated using the ArcGIS 9.2.

Mentions: The 2008 Wenchuan event triggered at least 197,481 landslides, with a total coverage area 1,160 km2 and an approximately distribution elliptical area larger than 110,000 km2 (A1 in Fig. 1A). The smallest landslide only covers 30 m2. Of the big dataset, 196,007 landslides with a total coverage area 1150.8 km2 are located in a 44,000-km2 area21 with relatively higher landslide abundance (A2 in Fig. 1A), including 25,580 individual landslides with planar area larger than 10,000 m2 (Fig. 1B). The quake ruptured two main faults and generated two surface ruptures, which are 240 km and 72 km long22. The pattern of the coseismic landslides shows a consistent distribution with the coseismic ruptures. We collected SPOT 5 stereoscopic pairs of image-derived pre- and post-quake DEMs (Fig. 1C,D) with high resolution (20 m) in a 19,969-km2 irregular polygon (A3 in Fig. 1A), which is totally enclosed in the landslide dense area (A2 in Fig. 1A). The quality of pre-quake DEM is quite satisfactory (Fig. 1C) whereas the post-quake DEM shows about 2,483-km2-covered patches without data (Fig. 1D), which was probably due to the impact of clouds. The areas without data were filled by the linear interpolation method and then the pre-and post-quake DEMs were employed to derive DEM differentials, which were used for calculating individual landslide volumes of deposit areas and scar areas.


Optimized volume models of earthquake-triggered landslides.

Xu C, Xu X, Shen L, Yao Q, Tan X, Kang W, Ma S, Wu X, Cai J, Gao M, Li K - Sci Rep (2016)

Distribution maps of landslides triggered by the 2008 Wenchuan earthquake and landslide volume samples.(A) Distribution of 197,481 landslides21. (B) Distribution of 25,580 individual landslides with area larger than 10,000 m2. (C) 1,415 landslide samples (denoted by polygons) on pre-quake DEM (20 m). (D) The samples (denoted by points) and areas without data on post-quake DEM (20 m). A1, the approximately distribution elliptical area of landslides larger than 110,000 km2; A2, the 44,000-km2 area with relatively higher landslide abundance; A3, the coverage area of pre- and post-quake DEMs. The colorful hillshade backgrounds on the panels A-D are from SRTM DEM23 (90 m) based on the ArcGIS 9.2 Platform (http://www.esri.com/apps/products). The pre- and post-quake grey DEMs on the panels C and D are from SPOT 5 stereoscopic pairs of images. All the four figures were also generated using the ArcGIS 9.2.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4940731&req=5

f1: Distribution maps of landslides triggered by the 2008 Wenchuan earthquake and landslide volume samples.(A) Distribution of 197,481 landslides21. (B) Distribution of 25,580 individual landslides with area larger than 10,000 m2. (C) 1,415 landslide samples (denoted by polygons) on pre-quake DEM (20 m). (D) The samples (denoted by points) and areas without data on post-quake DEM (20 m). A1, the approximately distribution elliptical area of landslides larger than 110,000 km2; A2, the 44,000-km2 area with relatively higher landslide abundance; A3, the coverage area of pre- and post-quake DEMs. The colorful hillshade backgrounds on the panels A-D are from SRTM DEM23 (90 m) based on the ArcGIS 9.2 Platform (http://www.esri.com/apps/products). The pre- and post-quake grey DEMs on the panels C and D are from SPOT 5 stereoscopic pairs of images. All the four figures were also generated using the ArcGIS 9.2.
Mentions: The 2008 Wenchuan event triggered at least 197,481 landslides, with a total coverage area 1,160 km2 and an approximately distribution elliptical area larger than 110,000 km2 (A1 in Fig. 1A). The smallest landslide only covers 30 m2. Of the big dataset, 196,007 landslides with a total coverage area 1150.8 km2 are located in a 44,000-km2 area21 with relatively higher landslide abundance (A2 in Fig. 1A), including 25,580 individual landslides with planar area larger than 10,000 m2 (Fig. 1B). The quake ruptured two main faults and generated two surface ruptures, which are 240 km and 72 km long22. The pattern of the coseismic landslides shows a consistent distribution with the coseismic ruptures. We collected SPOT 5 stereoscopic pairs of image-derived pre- and post-quake DEMs (Fig. 1C,D) with high resolution (20 m) in a 19,969-km2 irregular polygon (A3 in Fig. 1A), which is totally enclosed in the landslide dense area (A2 in Fig. 1A). The quality of pre-quake DEM is quite satisfactory (Fig. 1C) whereas the post-quake DEM shows about 2,483-km2-covered patches without data (Fig. 1D), which was probably due to the impact of clouds. The areas without data were filled by the linear interpolation method and then the pre-and post-quake DEMs were employed to derive DEM differentials, which were used for calculating individual landslide volumes of deposit areas and scar areas.

Bottom Line: The samples were used to fit the conventional landslide "volume-area" power law relationship and the 3 optimized models we proposed, respectively.Two data fitting methods, i.e. log-transformed-based linear and original data-based nonlinear least square, were employed to the 4 models.Results show that original data-based nonlinear least square combining with an optimized model considering length, width, height, lithology, slope, peak ground acceleration, and slope aspect shows the best performance.

View Article: PubMed Central - PubMed

Affiliation: Key Laboratory of Active Tectonics and Volcano, Institute of Geology, China Earthquake Administration, Beijing, 100029, China.

ABSTRACT
In this study, we proposed three optimized models for calculating the total volume of landslides triggered by the 2008 Wenchuan, China Mw 7.9 earthquake. First, we calculated the volume of each deposit of 1,415 landslides triggered by the quake based on pre- and post-quake DEMs in 20 m resolution. The samples were used to fit the conventional landslide "volume-area" power law relationship and the 3 optimized models we proposed, respectively. Two data fitting methods, i.e. log-transformed-based linear and original data-based nonlinear least square, were employed to the 4 models. Results show that original data-based nonlinear least square combining with an optimized model considering length, width, height, lithology, slope, peak ground acceleration, and slope aspect shows the best performance. This model was subsequently applied to the database of landslides triggered by the quake except for two largest ones with known volumes. It indicates that the total volume of the 196,007 landslides is about 1.2 × 10(10) m(3) in deposit materials and 1 × 10(10) m(3) in source areas, respectively. The result from the relationship of quake magnitude and entire landslide volume related to individual earthquake is much less than that from this study, which reminds us the necessity to update the power-law relationship.

No MeSH data available.


Related in: MedlinePlus