Lake Bandung

The Bandung basin is an ellips-formed geological basin measuring 60 kilometres east-west, and 40 kilometres north-south, spanning from Padalarang in the west to Nagreg in the east, from Mount Tangkuban Perahu in the north to Mount Malabar in the south. The Bandung basin is surrounded by volcanic domes formed during the quaternary period in most sides, with only the western parts are dated older. Its stones were formed during the Neogene period, consisting mostly of limestones, creating Padalarang karst mountain.[1] It is suggested that the Bandung basin is a multiple volcanic caldera system, created by both volcanic and tectonic activity as there are numbers of tectonic fault crossing the Parahyangan highland. For example, there is a Lembang fault that runs west-east axis located immediately north of Bandung under the town of Lembang. Sedimentation of the Bandung basin started around 126,000 BCE, which suggested that Bandung paleo-lake was first formed during this period.

The formation of the lake went further through the eruption of Mount Sunda. The paleo Sunda volcano — the predecessor of Tangkuban Perahu-Burangrang-Bukit Tunggul volcanic system — is estimated to have erupted 53,000 BCE. As the violent plinian eruption caused the conic stratovolcano to collapse and blocked the course of Citarum river, a natural dam was formed, turning the basin into a lake known as "the Great Prehistoric Lake of Bandung".[2]

The archaeological findings around the lake discovered several obsidian stone tools, suggesting that the surrounding area once supported early human habitation that provides water and food. All of these obsidian tools were discovered on elevation above 700 metres above the sea level, which suggested that the lake surface was once formed around this elevation.

According to geological studies, the Bandung paleo-lake sedimentation formation was last formed 18,000 BCE and started to dry up during that period. The cause of the drying up is a subject of study. It is suggested that either tectonic or volcanic activities in the area, or gradual erosion, has caused the natural dam to collapse and leaked the basin, draining the lake's water into the Citarum river.[1]

There is a Sundanese legend of Sangkuriang that mentions the existence of the lake, as well as the mythical origin on the lake's creation and Mount Tangkuban Perahu. This might suggest the collective native Sundanese memories about the lake's existence, transmitted through oral tradition in the Pantun Sunda through the ages.