The 1922 Peninsula Malaysia Earthquakes: Rare Intraplate Seismicity within the Sundaland Block in Southeast Asia

Abstract

Seismic hazard in the southern Malay Peninsula located within the Sundaland block in Southeast Asia is poorly understood. The paucity of historical earthquakes and low-magnitude instrumented seismicity has led to the assumption that this region is largely aseismic. We question this point of view by reassessing historical seismicity in this region and, in particular, a pair of moderate earthquakes in the 1920s. The first of these struck on 31 January 1922 at ≈9:10 a.m. local time (LT) for which we estimate an intensity magnitude (MI) ≈5.4, and for the second earthquake on 7 February 1922 at ≈12:15 p.m. LT, we estimate MI≈5.0. We also identify at least 34 felt earthquakes between 1803 and 1950 that were potentially local within the Sundaland block. These include a very widely felt shock (or set of shocks) on 26 June 1874 that was felt in parts of Borneo, Java, and Sumatra. The discovery of these earthquakes challenges the tectonic stability of the Malay Peninsula and the stable interior of the Sundaland block. The record of historical seismicity in this region relies heavily on European sources, and we recommend locating and consulting indigenous sources to improve the current understanding of regional seismic hazard. We also underscore the need to evaluate the impact of ground motions from rare local earthquakes on the extant building stock and on transportation infrastructure that are otherwise relatively immune to the long-period effects of distant earthquakes commonly felt in the Malay Peninsula.

Gempa Nusantara: A Database of 7380 Macroseismic Observations for 1200 Historical Earthquakes in Indonesia from 1546 to 1950

“…Colonial expansion on Borneo was stymied by inhospitable conditions and competition from Chinese and Malay interests (Missen, 1972;Rickleffs, 1981). Despite the remoteness of the Bornean interior, the limited number of historical earthquake observations collated by us (Table S2) and by Martin et al (2020a) still appear to reflect the low modern geodetically determined strain rates of ~7 nanostrain/year within the interior of the Sundaland block (Figure 1, e.g., Simons et al, 2007;Mustafar et al, 2017). The only exception in Borneo is the region extending from northern Borneo to the Mangkalihat Peninsula (Figure 3a) where we have documented several large historical earthquakes.…”

Intraplate earthquake occurrence and distribution in Peninsular Malaysia over the past 100 years

“…3, Tables S2 and S3). The first two historical earthquakes were reported by Martin et al [26] which occurred in the southern part of the region; however, all information were estimated based on intensity observations, and no depth values are available. Event no.…”

“…In a recent paper by [26] two earthquakes that occurred in the southern part of the Malay Peninsula in 1922 were analyzed. The first one occurred on January 31,1922, and the second one on February 7, 1922, with an M I 5.4 and M I 5.0, respectively.…”

Structure Vulnerability and Risk Analysis of 4-Legged Offshore Structure

“…In Malaysia, earthquake hazards are still poorly understood and have yet to be thoroughly quantified due to lack of basic scientific data [12,13]. Moreover, time history data of Malaysia are not well documented and archieved.…”