Woodlark

History

The past. The ice age: the sea stood about 120 metres lower, and some 30,000 square kilometres of today’s reefs and shallows were dry land; the Trobriands and the D’Entrecasteaux Islands were one island, almost five times their size today. In the mountains, from Enga and Mount Giluwe to Mount Wilhelm and the Owen Stanley Range, the forest ended near 2,300 metres, about 1,500 metres lower than today, and some 20,000 square kilometres above it were grassland with tree ferns, with glaciers on the highest peaks. The sea was already low when the timeline begins, and the cold was deepest 22,500 to 19,400 years ago. The forest began to climb back 17,113 years ago and reached 4,000 metres by about 9,600 years ago; the rising sea had drowned nearly all of the reefs by 7,050 years ago. The lines that stand for the forest turn toward grassland and the lines that stand for the sea turn to the colour of land, all at once, and only across those spans.

6 million years ago

Continental rifting began that would open the Woodlark Basin, with new ocean floor following from east to west.

Sources: Walker and Flenley 1979, Philosophical Transactions of the Royal Society B 286:265; Haberle 1993, PhD thesis, Australian National University; Hope 2014, Arctic, Antarctic, and Alpine Research 46:777; Lambeck et al. 2014, PNAS 111:15296 · Taylor, Goodliffe and Martinez 1999, Journal of Geophysical Research 104:7497