New research highlights significant earthquake potential in Indonesia’s capital city

The Jakarta Fault runs beneath the southern part of the capital city of Indonesia, Jakarta. Jakarta is one of the largest cities in the world, with a population exceeding 30 million in the metropolitan area. New research by BGS and Indonesian colleagues shows that this fault could generate a magnitude 6.5 earthquake, which would expose a large number of people as well as significantly important economic infrastructure to strong ground shaking.

Between 2019 and 2023, Indonesian scientists from the Institut Teknologi Bandung (ITB), National Research and Innovation Agency (BRIN) and the Geospatial Information Agency (BIG) collected ground movement data across the Jakarta Fault from a dense network of global navigation satellite systems (GNSS). These measurements revealed slow, millimetre-scale changes in ground movement occurring across the fault, which indicated energy accumulating that will need to be released, potentially in a future earthquake.

Geophysical modelling shows that ground movement is accruing on the fault at 3.2 mm per year, with the fault locked or ‘stuck’ down to at least 7.2 km. This accumulation has been happening for at least 210 years, which means that releasing it all now would result in a magnitude 6.5 earthquake.

While magnitude 6.5 earthquakes are not uncommon in Indonesia, they mostly occur under the ocean. The danger here is that the earthquake could occur in the middle of a densely built-up area like Jakarta, which means a much higher level of risk to life and infrastructure.

Dr Ekbal Hussain, remote sensing geoscientist at BGS and research co-leader.

The Jakarta Fault is a relatively newly recognised major tectonic fault on the Indonesian island of Java. It is a part of a broader fault system that cuts across most of Java, which, with a population of 157 million people, is the most densely populated island on Earth. Geophysical surveys conducted by BGS in the 1970s and 1980s, in collaboration with the Indonesian Geological Research and Development Center, helped identify this major tectonic structure for the first time, but its earthquake potential has remained unclear until now.

This research forms part of strategic UK/Indonesia research partnerships on geological hazard solutions, as outlined in a recently published White Paper, UK/Indonesia partnerships for advancing geohazard science for disaster risk assessment in Indonesia. The paper, co-developed by key Indonesian and UK hazard experts, presents a strategic roadmap to significantly reducing the impacts of geological hazards in the country. Importantly, it highlights the strength of UK and Indonesian science partnerships for delivering the best disaster resilience science.

More information

Access the full paper: GNSS constraints on the Jakarta Fault, Indonesia: resolving slip rate and seismic hazard potential

Funding

This is work is funded by the UKRI National Capability Geoscience to tackle global environmental challenges programme. The BGS and Indonesian researchers involved in this study are continuing their engagement with local government to address the hazard challenges raised in this work.