The geologic story of the Teton country from the time the earth was new
to the present day has been summarized. What can we learn from it? We
become aware that events recorded in the rocks are not a chaotic jumble
of random accidents but came in an orderly, logical succession. We see
the majestic parade of life evolving from simple to complex types,
overcoming all natural disasters, and adapting to ever-changing
environments. We can only speculate as to the motivating force that
launched this fascinating geologic and biologic venture and what the
ultimate goal may be. New facts and new ideas are added to the story
each year, but many unknown chapters remain to be studied; these offer
an irresistible, continuing challenge to inquisitive minds, strong
bodies, and restless, adventurous spirits.
Most geologic processes that developed the Teton landscape have been
beneficial to man; a few have interfered with his activities, cost him
money, time, effort, and on occasion, his life. Postglacial faulting and
tilting along the southern margin of Grand Teton National Park diverted
drainage systems (such as Flat Creek, southwest of the Flat Creek fault
on the south edge of the geologic map), raised hills, dropped valleys,
and made steep slopes unstable. Flood-control engineers wage a
never-ending struggle to keep the Snake River from shifting to the west
side of Jackson Hole as the valley tilts westward in response to
movement along the Teton fault. Each highway into Jackson Hole has been
blocked by a landslide at one time or another and maintenance of roads
across slide areas requires much ingenuity. We see one slide (the Gros
Ventre) that blocked a river; larger slides have occurred in the past,
and more can be expected. Abundant fresh fault scarps are a constant
reminder that public buildings, campgrounds, dams, and roads need to be
designed to withstand the effects of earthquakes. Some of these problems
have geologic solutions; others can be avoided or minimized as further
study increases our understanding of this region.
Man appeared during the last one-fiftieth of an inch on our yardstick of
time gone by. In this short span he has had more impact on the earth and
its inhabitants than any other form of life. Will he use wisely the
lessons of the past as a guide while he writes his record on the
yardstick of the future?