A magnitude 5.2 earthquake hit Cianjur Regency, West Java, Indonesia on November 21, 2022, killing more than 300 people, leaving many more missing, and damaging more than 60,000 houses which caused thousands of people to be displaced from their homes. Significant seismic activity was recognized in 1699, 1834, 1879, and 1900 near Cianjur in West Java. The news quickly hit social media, with some responding in group chats, feeds, reels, and literature reviews shared via other social media claiming that the Cimandiri Fault had caused the event. Moreover, discussions were featured in webinars and on national television. However, this information was based solely on limited information and prior knowledge of the area without further analysis of the actual data.
New satellite data was uploaded via social media a few days later. This update soon reduced online discussion about the Cimandiri Fault. There was further evidence of a previously buried fault between the Cimandiri Fault and the Gede Pangrango Range, 12 km north of the estimated location of the Cimandiri Fault. Our field observations indicate that this fault caused most of the rupture in this region.
Socially, the earthquake event also caused immediate problems in the local community. There have been incidents of earthquake survivors, donors, and people taking advantage of the situation. Blockades were everywhere, and those claiming to be survivors demanded that oncoming donation fleets be stopped, and all donations abandoned. These incidents have hampered efforts to distribute aid to the most remote areas. As a result, survivors who had taken refuge far from major logistical lines were left stranded. Heartless selfies and video content created in the face of grieving communities are everywhere and create a rift between survivors and donors.
The recent Cianjur earthquake has taught us how important it is to understand the geological phenomena behind our homes and the effect of information and misinformation via social media. While social media serves as a valuable tool for rapid information dissemination during disasters, verifying information from reliable sources and encouraging responsible usage of social media platforms is essential. Effective filtering of information becomes pivotal to combat misinformation in developing more resilient communities, safeguarding lives, and minimising the impact of the disaster.