A CHRONOLOGY FOR GEOMORPHOLOGICAL DEVELOPMENTS IN THE GREATER BANDUNGAREA, WEST-JAVA, INDONESIA

The greater Bandung area (West-Java, Indonesia) is a large intramontan e basin surrounded by volcanic highlands. Geomorphological and sedimen tological studies reveal that the morphology of the central basin and the Sunda-Tangkuban Perahu volcanic complex developed during the Middl e-Late Quaternary, in particular since 125 kyr B.P. Tectonic subsidenc e, paroxysmal eruptions, volcanism-induced faulting/rifting, drainage system adaptations and intramontane lacustrine sedimentation (partly g eomorphology-controlled) constitute the dominant landform-determining processes. A reconstruction of the regional morphological development is based on interpretation of morphological features and morphodynamic processes in the volcanic upland, in combination with analysis of the sedimentary record in the basin. A chronological framework is based o n datings obtained from surficial sediments and deep drill cores. Init ially, long term patterns in volcanicity and tectonic effects determin e regional sedimentation and relief development in the greater Bandung area. Fluvial sedimentation and weathering prevailed in the basin, wh ile the southern and northern volcanic ranges gradually formed. Basin subsidence, with contemporaneous volcanism around 125 kyr B.P., result ed in the formation of an enclosed intramontane basin, and stimulated lacustrine sedimentation. From this time on, concentration of volcanic ity in the northern Sunda-Tangkuban Perahu complex and the resulting m orphostructural developments caused rapid (catastrophic) and localized morphological changes. Cataclysmic eruptions (around 105 kyr B.P. and 50-35 kyr B.P.) caused voluminous sediment inflow in the northwestern basin. These events mark the significance of the Sunda-Tangkuban Pera hu volcanic centre during the Late Quaternary; the Sunda volcano colla psed into a caldera in which later the Tangkuban Perahu volcano develo ped. Moreover, these eruptions controlled regional sedimentation and d etermined landform development in the greater basin area. In the vicin ity of the eruption centre, volcano-tectonic faulting formed the consp icuous E-W Lembang fault that controlled distribution of volcaniclasti c sediments and the initiation of a new drainage system in the Lembang area. In the low-lying Bandung plain persistent (fluvio)lacustrine an d volcaniclastic sedimentation, followed by basin subsidence and minor fluvial erosion characterised the younger phases of landform developm ent. Copyright (C) 1996 Elsevier Science Ltd