Irian JayaWiki info
The island of New Guinea was once part of the Australian landmass and lies on the continent of Sahul. The collision between the Indo-Australian Plate and Pacific plate resulted in the formation of the Maoke Mountains, which run through the centre of the region and are 600 km (373 mi) long and 100 km (62 mi) across. The range includes about ten peaks over 4,000 metres (13,000 feet), including Puncak Jaya (4,884 m or 16,024 ft), Puncak Mandala (4,760 m or 15,620 ft) and Puncak Trikora (4,750 m or 15,580 ft). This range ensures a steady supply of rain from the tropical atmosphere. The tree line is around 4,000 m (13,100 ft) and the tallest peaks feature small glaciers and are snowbound year-round. Both north and west of the central ranges, the land remains mountainous – mostly 1,000 to 2,000 metres (3,300 to 6,600 feet) high with a warm humid climate year-round. The highland areas feature alpine grasslands, jagged bare peaks, montane forests, rainforests, fast-flowing rivers, and gorges. Swamps and low-lying alluvial plains with fertile soil dominate the southeastern section around the town of Merauke. Swamps also extend 300 kilometres (190 miles) around the Asmat region.