The northern and western coasts of Alaska are mostly low, and correspond
in a general way with the coastal plan of the Carolina region. The last
well-marked movement of the land in that region has been in the
direction of an elevation, and we find low shores, with but few
harbours, similar in many ways to the coast of Texas.
It is probably true, as already stated, that the Aleutian Islands,
although in part the result of recent volcanic activity, owe their
peculiar and exceptional characteristics to the partial subsidence of a
deeply sculptured mountain range. On the south coast of Alaska, in the
region of Mount St. Elias and Mount Fairweather, a recent and
extensive elevation has occurred, which, however, did not bring the
bottom of the adjacent portion of the ocean above the sea-level. This
apparent anomaly seems to be due to an uprising of the rocks along the
north side of a break, or belt of branching fractures, which closely
approximates to the coast-line and has determined the position of the
continental border in that region. The facts, so far as known, appear to
show that we have here what geologists term a fault, the north or
landward side of which has been raised at least 5,000 feet in very
modern times, but, so far as we can judge, without disturbing the
seaward border of the break. The coast between Mount Fairweather and
Mount St. Elias is by far the boldest, and from a scenic point of view
the most impressive, portion of the entire shore-line of North America.
The mountains are young and among the highest on the continent. They
rise precipitously from the margin of the sea, and are sheathed in snow
and ice from base to summit throughout the year.
The margin of the continent southward from Mount Fairweather to the
Columbia River, a distance in a straight line of about 1,200 miles,
furnishes some of the best illustrations of the changes in coastal
geography due to subsidence that our continent affords (Fig. 11). This
wonderfully irregular coast is fringed with a belt of mountainous
islands from 50 to 100 or more miles broad. The inlets between the bold
capes and the straits separating the numerous islands are deep. The
rugged, forest-clothed slopes with precipitous, and in many instances
nearly vertical walls, descend into water that is frequently from 50 to
over 200 fathoms deep. In brief, a deeply dissected mountain range more
than 1,000 miles in length has there been depressed at least 2,000 feet
below its former altitude, thus allowing the sea to flood its deep,
picturesque valleys.
Public-domain text, read in full here on John Shaqi.
Reviews
Reviews
No reviews yet
Be the first to share your thoughts on this work.
Join the Discussion
Join the discussion
Sign in to leave a comment or review.
Sign InorCreate an account