Earthquake History of the Sumatran Fault, Indonesia, since 1892, Derived from Relocation of Large Earthquakes

Structural Controls on Rupture Extent of Recent Sumatran Fault Zone Earthquakes, Indonesia

“…Journal of Geophysical Research: Solid Earth segment had been classified as a seismic gap along the SFZ (Hurukawa et al, 2014;Natawidjaja & Triyoso, 2007). The Dikit segment is limited by an~3-km-wide step over between its southeastern end and the Ketauan segment ( Figure 5), and an~11-km-wide step over between its northwestern end and the Siulak segment (Sieh & Natawidjaja, 2000) (Figure 5).…”

“…Concerns about the potential seismic hazard of the SFZ have escalated after a series of M w > 8 earthquakes (the 26 December 2004 M w 9.2 Sumatra-Andaman event, the 28 March 2005 M w 8.6 Nias-Simeulue event, and the 12 September 2007 M w 8.4 Bengkulu event) were generated by the Sunda megathrust offshore Sumatra, starting in 2004. These large megathrust events increased stress loading on the SFZ (Cattin et al, 2009;Nalbant et al, 2005;Sørensen & Atakan, 2008) and likely triggered more frequent moderate seismicity along the SFZ, including five 6 ≤ M < 7 earthquakes: the 2007 M w 6.4 and 6.3 earthquakes (Daryono et al, 2012;Nakano et al, 2010) that caused 69 fatalities and more than 100 injuries (hereafter referred to as the 2007 Lake Singkarak doublet); the 2008 M w 6.0 Toru earthquake that broke the Toru segment (Hurukawa et al, 2014); the 2009 M w 6.6 earthquake that broke the Dikit seismic gap (Hurukawa et al, 2014) (hereafter referred to as the 2009 Dikit event); and the January 2013 M w 6.1 earthquake that ruptured the Aceh creeping segment (Ito et al, 2016) (Figure 1). The 2008 Toru, the 2009 Dikit, and the January 2013 Aceh events did not cause casualties.…”

“…To better assess seismic hazard potential of earthquakes in mainland Sumatra, published studies have focused on paleoearthquakes (Bellier et al, 1997), epicenter relocations (Hurukawa et al, 2014;Newcomb & McCann, 1987;Nugraha et al, 2018;Pesicek et al, 2010), aftershock distributions (Muzli et al, 2018;Widiwijayanti et al, 1996), field observations of surface ruptures (Daryono et al, 2012;Daryono & Tohari, 2016;Untung et al, 1985), deterministic and probabilistic hazard assessments (Natawidjaja & Triyoso, 2007), active fault mapping (Fernandez-Blanco et al, 2016;Muksin et al, 2019;Natawidjaja et al, 2017;Sieh & Natawidjaja, 2000;Weller et al, 2012), fault slip rates (Bellier & Sebrier, 1995;Bradley et al, 2017;Genrich et al, 2000;Ito et al, 2012;Natawidjaja et al, 2017;Prawirodirdjo et al, 2000;Tong et al, 2018), in situ stress analysis (Sahara et al, 2018), source characteristics of ruptures (Duquesnoy et al, 1996;Gunawan et al, 2018;Ito et al, 2016;Prawirodirdjo et al, 2000;Reid, 1913), and postseisimic processes (Gunawan et al, 2019). However, none of these studies used well-constrained near-field geodetic data to address the seismogenic depth and spatial distribution of coseismic slip, or to study the nature of the tectonic features that control earthquake rupture sizes along the SFZ.…”

Major Bifurcations, Slip Rates, and A Creeping Segment of Sumatran Fault Zone in Tarutung-Sarulla-Sipirok-Padangsidempuan, Central Sumatra, Indonesia

“…SFZ in Central Sumatra region with slip rates from this study. The black stars are relocated epicentres of past earthquakes along the Sumatran Fault Zone (Hurukawa, 2014).…”

Analisis Coulomb Stress Gempa Bumi Deli Serdang 16 Januari 2017

“…Data waktu tiba gempabumi diperoleh dari BMKG [8] dengan batasan 3 o -4 o LU dan 97 o -99 o BT. Relokasi data gempabumi susulan menggunakan metode Relokasi Modified Joint Hypocenter Determination (MJHD) [9] dilakukan untuk menentukan bidang sesar dari dua bidang nodal.…”