Frequency–magnitude of landslides affected by the 27–29 November 2017 Tropical Cyclone Cempaka in Pacitan, East Java  

作　　者：SAMODRA Guruh NGADISIH Ngadisih MALAWANI Mukhamad Ngainul MARDIATNO Djati CAHYADI Ahmad NUGROHO Ferman Setia 

机构地区：[1]Disaster Research Centre(PSBA),Universitas Gadjah Mada,Yogyakarta 55281,Indonesia [2]Laboratory of Environmental Geomorphology and Disaster Mitigation,Faculty of Geography,Universitas Gadjah Mada,Yogyakarta 55281,Indonesia [3]Department of Agricultural and Biosystems Engineering,Faculty of Agricultural Technology,Universitas Gadjah Mada,Yogyakarta 55281,Indonesia [4]Laboratory of Hydrology and Environmental Climatology,Faculty of Geography,Universitas Gadjah Mada,Yogyakarta 55281,Indonesia [5]Remote Sensing Ground Station Parepare,Indonesian National Institute of Aeronautics and Space,Sulawesi Selatan 91112,Indonesia

出　　处：《Journal of Mountain Science》2020年第4期773-786,共14页山地科学学报（英文）

基　　金：partially supported by Hibah Rekognisi Tugas Akhir 2019(No.2129/UN1/DITLIT/DIT-LIT/LT/2019)。

摘　　要：Tropical cyclone(TC) Cempaka which occurred on 27–29 November 2017 has caused floods, landslides, and strong winds in certain areas of Java Island. Pacitan Regency was the most severely affected by TC Cempaka. The landslide frequency–area distribution curve of event inventory i.e. TC Cempaka can help to understand landslide susceptibility, hazard, vulnerability, and risk. Landslides were identified by using a local government database and by comparing pre-and post-event high-resolution satellite imageries. Field investigation was carried out in March 2018 to November 2018 to verify the landslide location and update the information. Power law, inverse gamma, and double Pareto model were employed to describe the frequency–magnitude of landslide(mLS) triggered by TC Cempaka. The exponent β values of power law, inverse gamma, and double Pareto were 2.6±0.28(fitted for 8.5% of dataset), 2.2±0.08(fitted for 83% of dataset), and 2.3±0.09(best fitted for dataset), respectively. The P-values were 0.51, 0.67, and 0.91 for power law, inverse gamma, and double Pareto, respectively. This study revealed that rollover occurred at 200 and 300 m2 for double Pareto and inverse gamma, respectively. The cutoff points totaled 1096.49 ± 236.44 and 7235.4 ± 1896.7 m2 for double Pareto and power law, respectively. Rollover phenomenon was real and existed in the dataset because it was far from the minimum resolvable size of the landslide that the authors can delineate from the satellite images. mLS for Pacitan was distributed at around 2 to 4. The magnitude of large landslides was 3.2, that of medium landslides was less than 3, and that of small landslides was almost 4. Numerical estimation calculated a fixed mLS=3.01. Comparison analysis of β values obtained from several landslide inventories triggered by heavy rainfall suggests that the variability of β is related to the intensity and duration of rainfall. Triggering events, such as intensity and duration of rainfall, affect the proportion of large landslides that occur i

关 键 词：LANDSLIDE Tropical cyclone LANDSLIDE MAGNITUDE FREQUENCY DISTRIBUTION Area DISTRIBUTION Pacitan REGENCY 

分 类 号：P642.22[天文地球—工程地质学]