Quaternary Urban Geology and the Foundation of Heritage Building: Notable Historical Cases in Sawahlunto, Indonesia

Sawahlunto is a city located in West Sumatra, Indonesia, known as a city rich in coal mining activities and often referred to as the “City of Batubara.” The history of Sawahlunto coal mining dates back to the Dutch colonial era in the late 19th century when coal was discovered in the area. It has been designated as a national geopark area (KGN) in 2018 and then designated as a UNESCO World Heritage Site (WDU) in 2019. One of its prominent landmarks is the Ombilin Coal Mine, which. Sawahlunto also boasts other historical landmarks and preserved buildings. The study objectives are: to identify rock types, topographic features, and other phenomena, along with measurements of heritage buildings; to analyze the rock distribution for determining the origin of rocks for heritage buildings in urban development and to describe the heritage building; and to describe the development of heritage building in Sawahlunto The mixed method was incorporated, where geological mapping method was used to determine information on the distribution of rocks and material origin for urban development, heritage building foundation analysis and content analysis on heritage buildings. The study found the building materials are rocks from the result of erosion originating around the city of Sawahlunto are: Sedimentary rock facies in the Ombilin Basin. The heritage buildings used local materials as they were abundant during that time. Sawahlunto’s heritage buildings not only have historical and cultural heritage, but also contain urban geological heritage that should be further studied as part of urban development.