Holiday in Lombok Island with Trekking Adventure

Tambora: General Info

Tambora is on Sumbawa Island along the east Sunda Arc. It lies some 300 kilometers behind the Sunda Trench, but the subduction zone in that area has a shallow dip and is less than 200 kilometers deep beneath Tambora (Alzwar and others, 1981). Tambora is a large stratovolcano composed dominantly of nepheline-normative, leucite-bearing trachybasalt and trachyandesite (Petroeschevsky, 1949; Foden and Varne, 1980; Alzwar and others, 1981; Barberi and others, 1983; Self and others, 1984; Foden, 1986). Before its eruption in 1815, Tambora might have been in repose for as much as 5,000 years (Barberi and others, 1983).
At least 6 months and probably about 3 years of increased steaming and small phreatic eruptions preceded the 1815 Tambora eruption, the largest in historical time (Stewart, 1820; Zollinger, 1855; Crawfurd, 1856; Stothers, 1984; Sigurdsson and Carey, 1987). A moderately large explosive eruption occurred on 5 April 1815, from which ash fell in east Java and thunderlike sounds were heard up to 1,400 kilometers away. A still larger eruption occurred on 10-11 April, beginning as “three columns of fire rising to a great height” (Zollinger, 1855, p.19) and ultimately ejecting about 50 cubic kilometers of magma (dense rock equivalent) (Self and others, 1984; Sigurdsson and Carey, 1987). the eruption left a deep summit caldera where previously a much higher stratovolcano had stood. Earthquakes were felt as far away as Surabaya (500 kilometers), possibly reflecting the caldera collapse.
A small, postcaldera cone and lava flow, Doro Afi Toi, originated sometime between 1847 and 1913 (Pannekoek van Rheden, 1918; Neumann van Padang, 1951). A strong earthquake on 13 January 1909, with an epicenter near Tambora (8.5degreesS, 117.4degreesE), was “presumably connected with Tambora.