We present analysis of the December 2018 Anak Krakatau tsunami in Sunda Strait, Indonesia, from a combination of post-tsunami field surveys, bathymetric changes and spectral analysis of the tsunami tide gauge records. Post-tsunami surveys revealed moderate tsunami height along the coast of Sumatra and Java with maximum surveyed runup of 13.5 m and maximum inundation distance of 330 m. At small islands located close to the volcano, extreme tsunami impacts were observed indicating not only a huge tsunami was generated by large amounts of collapse material which caused notable changes of seafloor bathymetry, but also indicates the role of those small islands in reducing tsunami height that propagated to the mainland of Indonesia. Our spectral analysis of tide gauge records showed that the tsunami's dominant period was 6.6-7.4 min, indicating the short-period nature of the 2018 Sunda Strait tsunami.

A systematic pattern of destruction was observed caused by the Mw 7.5 Central Sulawesi Earthquake. In brief, the quake ruptured 180 km of Palu–Koro Fault and led to massive destruction of residential buildings in Palu city, Donggala and Sigi Regencies. In Palu city, the damage was concentrated only in Balaroa and Petobo neighbourhoods where at least 930 and 1255 houses, respectively, collapsed. Microtremor time series recorded prior to the earthquake were used to analyse the subsurface structure of Balaroa and surroundings. Surprisingly, inversion of horizontal-to-vertical spectral ratio curves was able to locate the subsurface fault crossing the Balaroa and its dipping direction. Furthermore, the velocity profile deduced from this inversion points out the importance of local geology in the massive destruction in Balaroa. The existence of a subsurface pond led to an extremely water-saturated sandy soil underneath Balaroa. A combination of high level of water saturation and high peak ground acceleration (0.5–0.7 g) was strongly suspected to be the cause of the mega-liquefaction. The high degree of ground motion (>1.54 g) of spectral acceleration 0.2 s resulted in severe damage in elevated areas in Donggala, while in the Palu Basin, ground motion as high as 1.30g of spectral acceleration 0.5 s led to the destruction of four-storey or higher buildings.

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Lebong merupakan salah satu daerah rawan gempa bumi di Indonesia yang bersumber dari zona subduksi di laut dan sesar aktif di darat. Analisis morfotektonik dan sebaran pusat gempa bumi merusak memperlihatkan sumber gempa bumi daerah Lebong berasal dari sesar aktif Segmen Ketaun sesar Sumatra dan sesar Pelabai. Segmen Ketaun sesar Sumatra pernah mengakibatkan gempa bumi merusak pada 1952, dan sesar Pelabai mengakibatkan gempa bumi merusak pada 2017. Kejadian gempa bumi merusak 6 Desember 2017 memberikan pelajaran akan pentingnya upaya mitigasi gempa bumi di daerah Lebong. Hanya dengan upaya mitigasi tersebut dampak dari kejadian gempa bumi yang mungkin akan terulang di kemudian hari akan dapat diminimalisasi.

Serangkaian kejadian gempa bumi di Pulau Lombok dan sekitarnya pada 29 Juli 2018, 5 Agustus 2018, dan 19 Agustus 2018 mengakibatkan korban jiwa sebanyak 559 orang, 1.478 orang luka-luka, dan 185.483 bangunan mengalami kerusakan. Semua jenis bahaya gempa bumi, yaitu efek guncangan, sesar gempa bumi minor (minor fault surface rupture), dan bahaya ikutan berupa retakan tanah, likuefaksi, dan gerakan tanah muncul akibat gempa bumi tersebut. Guncangan gempa bumi terasa kuat di Lombok Utara dan Lombok Timur mencapai skala intensitas gempa bumi VIII MMI (Modified Mercally Intensity). Kejadian gempa bumi 29 Juli 2018 dengan M 6,4 mengakibatkan terbentuknya rupture zone: 218,7762 km2 . Adapun kejadian gempa bumi 5 dan 19Agustus 2018 dengan M 7,0 menghasilkan rupture zone: 758,5776 km 2.