Rising Seas and Earthquakes on the Sunda Shelf

Project Overview

Sea-level rise and earthquakes are separate hazards that can individually yet catastrophically impact communities, but little is known about each of these hazards near Singapore, owing to the brevity of local historical observations. In order to better quantify and appreciate each of these hazards, it is imperative that we extend the brief historical records farther back in time, using clues from geology. However, when it comes to studying past sea level or past tectonic deformation on the Sunda Shelf in Southeast Asia, the two problems become invariably intertwined. For instance, understanding the processes driving sea-level change in the past is crucial to improved forecasts for future sea-level change, but a poor understanding of local to regional tectonic deformation at different timescales limits our ability to map out the different processes contributing to sea-level change in any location. Likewise, past earthquakes could be recognized from associated uplift or subsidence of coastal regions, but first any contribution to sea-level change due to other processes would need to be quantified and removed from any measurements.

This leads to a critical “chicken-and-egg” situation in which we must substantially understand one problem in order to assess the other, yet currently we lack sufficient information about either. In order to overcome this dilemma and more reliably assess the threats from both earthquakes and sea-level rise, we aim to use coral microatolls to develop long, continuous records of relative sea level (RSL) at sites strategically located around the region. These geological records will allow us to better quantify rates of past RSL change; to identify abrupt changes in RSL; and to map out spatial and temporal patterns of past RSL change across the region. In combination with suitable modelling, these findings will elucidate the processes driving RSL and will allow us to better anticipate the hazards associated with future earthquakes and sea-level change in the region.

Funding Source

National Research Foundation

Project Years

2019 to 2024

Living coral microatolls on Mapur Island, near Singapore (Source: Imam Suprihanto)

Students on our research team sketching a fossil mid-Holocene coral microatoll on Lazarus Island, Singapore (Source: Aron Meltzner)

Sometimes we need to wake up early to catch the lowest tides, but we're rewarded by beautiful tropical sunrises. Tanjung Lokos, St. John’s Island, Singapore (Source: Aron Meltzner)