@article{oai:soar-ir.repo.nii.ac.jp:00016379,
 author = {Hehanussa,  P.E.},
 journal = {信州大学理学部附属諏訪臨湖実験所報告},
 month = {Mar},
 note = {A joint research on the geology of Lake Toba and its surrounding was executed by the Kyoto University and Indonesian Institute of Sciences during 1972-1988. The lake origin was explained by van Bemmelen (1949) as a volcano-tectonic depression. Ninkovich (1967) explained that Lake Toba is a caldera produced by a single eruption 70,000 years BC. Geological, geo-chronology, tephra-chronology, and gravity measurements by the Japan-Indonesia surveys revealed a more complex origin, the combined effect of volcanic, tectonic and sedimentation processes starting 1.9 M years ago (Nishimura et al. 1980). Lake Toba water area is 1,129 km² excluding the 647 km² Samosir Island and several other smaller islands in the lake. The morphology formed a topographic depression surrounded by steep cliffs 400 to 1200 m above lake surface. The water is at 904.5 m above sea level, maximum depth 585 m. The joint Japan-Indonesia finding is a strong base for planning a sustainable management for local people, forestry, fisheries, agriculture benefits, industrial developments, hydropower generation, and an everlasting scenic view for tourists., Article, 信州大学理学部附属諏訪臨湖実験所報告 12: 3-8(2000)},
 pages = {3--8},
 title = {LAKE TOBA, A MULTIPLE CALDERA DEPRESSION, NORTH SUMATERA, INDONESIA},
 volume = {12},
 year = {2000}
}