Page 96 - (DK) Ocean - The Definitive Visual Guide

94 COASTS AND THE SEASHORE

ATLANTIC OCEAN NORTHWEST
Greenland Ice Coast

TYPE Primary coast
FORMATION Extension of
ice-sheet to sea level in
outlet glaciers
EXTENT About 600 miles
(1,000 km)
LOCATION Parts of western and eastern coasts of
Greenland
An ice coast forms where a glacier
extends to the sea, so that a wall of ice
is in direct contact with the water.
This is a common feature around the
highly indented margins of Greenland,
mainly at the landward end of long
fjords. Together, these ice walls form
an interrupted ice coast, and they are
the source of enormous numbers of
icebergs, many of which escape the
fjords and eventually reach the
Atlantic. The ice coast extends along
only a fraction of the total Greenland
coastline, which is an astonishing
27,500 miles (44,000 km) long.

is found within a single large island, MOUNT DESERT ISLAND
ATLANTIC OCEAN NORTHWEST
Mount Desert Island, and some smaller The south-facing coast of Mount Desert Island
Acadia Coastline associated islands. Sea-level rise since consists of a series of fractured granitic steps
the last ice age has separated these that were produced by the action of glaciers
TYPE Primary coast islands from each other and from the some 100,000 years ago.
FORMATION Glaciation, mainland. The mountains that make
then drowning by up the basis of this coastline began separated by U-shaped valleys. Since
sea-level rise to form 500 million years ago from the ice sheet receded, the land has
EXTENT 41 miles (66 km) seafloor sediments. Magma (molten gradually rebounded upward, but
rock) rising up from Earth’s interior global sea-level rise has caused the
LOCATION Southeast of Bangor, Maine, intruded into and consumed these Atlantic to overtake the rebound at a
northeastern US sedimentary rocks, producing a mass rate of 2 in (5 cm) per century. Today,
of granite that was gradually eroded to waves and tidal currents are major
The coastline of Acadia in Maine is form a ridge. About 2–3 million years agents of change at Acadia, gradually
one of the most spectacular in the ago, a huge ice sheet started to blanket eroding the cliffs and depositing rock
northeastern US. It now forms the the area, depressing the land and particles mixed with shell fragments at
ICE COAST NEAR CAPE YORK Acadia National Park, most of which sculpting out a series of mountains coves around the coastline.

OCEAN ENVIRONMENTS STAIRWAY TO THE SEA

The tops of the columns form stepping
stones that first lead up from the foot of
the cliff to a mound and then progress
downward until they dip below the sea.