The 16-km-wide Tengger caldera is located at the northern end of a volcanic massif extending from Semeru volcano. The massive volcanic complex dates back to about 820,000 years ago and consists of five overlapping stratovolcanoes, each truncated by a caldera. Lava domes, pyroclastic cones, and a maar occupy the flanks of the massif. The Ngadisari caldera at the NE end of the complex formed about 150,000 years ago and is now drained through the Sapikerep valley. The most recent of the calderas is the 9 x 10 km wide Sandsea caldera at the SW end of the complex, which formed incrementally during the late Pleistocene and early Holocene. An overlapping cluster of post-caldera cones was constructed on the floor of the Sandsea caldera within the past several thousand years. The youngest of these is Bromo, one of Java's most active and most frequently visited volcanoes.
Bromo volcano steams at the left in this view from the rim of Ngadisari caldera, the older of two Tengger calderas. The pyroclastic cones of Bromo and the conical, parasol-ribbed Batok in the lower center, are two of several post-caldera cones of Tengger caldera. The towering conical peak of Semeru, Java's highest volcano, appears in the background at the end of a long N-S trending volcanic massif.
Photo courtesy of Volcanological Survey of Indonesia.
Last updated 2019-11-16 20:00:03