The Tasman Glacier is the largest of several glaciers which flow south and east towards the Mackenzie Basin from the Southern Alps in New Zealand's South Island. It is New Zealand's longest glacier.
At 27 kilometres (17 mi) in length, Tasman Glacier is New Zealand's longest glacier. It is as much as 4 kilometres (2.5 mi) wide and 600 metres (2,000 ft) thick, and lies entirely within the borders of Aoraki/Mount Cook National Park. The glacier covers an area of 101 square kilometres (39 sq mi) and starts at a height of 3,000 metres (9,800 ft) above sea level. Snowfall during the winter and spring seasons accumulates to 50 metres (160 ft). After the summer melt, 7 metres (23 ft) remains.
The Tasman flows south from the southern slopes of the Minarets peak, along the eastern flank of New Zealand's two highest mountains, Mount Tasman and its higher southern neighbour Aoraki/Mount Cook.
Although its upper reaches are snow-covered, rocks carried by the glacier are exposed by ablation along its course, and the lower glacier is entirely rock-covered. It is almost met near its end by the meltwater of the Murchison Glacier, which approaches from the northeast before turning to flow beside the Tasman Glacier outside the moraine wall.
The waters from both these glaciers pool at the end of the glacier in Lake Tasman, before flowing south to join the outflow from the nearby Hooker and Mueller Glaciers in the wide valley of the Tasman River, whose braided streams flow south into Lake Pukaki. They eventually flow into the Waitaki River and to the Pacific Ocean north of Oamaru.
A terminal moraine, also called end moraine, is a moraine that forms at the end of the glacier called the snout.
Terminal moraines mark the maximum advance of the glacier. An end moraine is at the present boundary of the glacier.
Terminal moraines are one of the most prominent types of moraines in the Arctic. One famous terminal moraine is the Giant's Wall in Norway which, according to legend, was built by giants to keep intruders out of their realm. It is now known that terminal moraines are created at the edge of the greatest extent of the glacier. At this point, the debris that has been accumulated by plucking and abrasion, that has been pushed by the front edge of the ice is driven no farther, but instead is dumped in a heap. Because the glacier acts very much like a conveyor belt, the longer it stays in one place, the greater the amount of material that will be deposited. The moraine is left as the marking point of the terminal extent of the ice.
In North America, the Outer Lands is a name given to the terminal moraine archipelago of the northeast United States (Cape Cod, Martha's Vineyard, Nantucket, Block Island and Long Island). Other prominent examples of terminal moraines are the Tinley Moraine and the Valparaiso Moraine, perhaps the best examples of terminal moraines in North America. These moraines are most clearly seen southwest of Chicago.