Geology of Indonesia active volcanoes formed Sumatra, Java, Bali, and Nusa Tenggara islands, most of which, particularly Java and Bali, emerged within the last 2–3 million years. The Pacific and Australian plate movements controlled the tectonics of the eastern portion of Indonesia. The tectonics processes in Indonesia formed major structures in Indonesia. The most prominent fault in the west of Indonesia is the Semangko Fault or the Great Sumatran Fault, a dextral strike-slip fault along Sumatra Island (about 1900 km). The formation of this fault zone is related to the subduction zone in the west of Sumatra. Palu-Koro fault is another major structural
Christianity in Indonesia from this, most other parts of North Sumatra have a significant Christianity percentage (around 20 to 40%), with the exception of Langkat, in the northeast coast, Asahan on the east coast, and the Mandailing regencies in the south which are Muslim majority (below 10%). Among Indonesian provinces in 2010, South Sumatra reported the eleventh-smallest number of Christians (114,671) or 0.49% of Christians within Indonesia. South Sumatra had the third-smallest percentage (among religions reported in the province) of Christians (1.54%), including the second-smallest percentage of Protestants (0.97%) and eighth-smallest percentage of Catholics (0.57%). West Sumatra province (population 4.8 million) is another