View west toward Grand Teton on skyline. Hedrick’s Pond surrounded
by “knob and kettle” topography is in foreground, tree-covered
Burned Ridge moraine is in middle distance, and extending from it to
foot of mountains is gray flat treeless glacial outwash plain.
_National Park Service photo by W. E. Dilley._
[Illustration: View west up Cascade Canyon, with north face of Mt.
Owen in center. _National Park Service photo by H. D. Pownall._]
_To Fritiof M. Fryxell, geologist, teacher,
writer, mountaineer, and the first ranger-naturalist
in Grand Teton National Park._
_All who love and strive to understand
the Teton landscape follow in his footsteps._
_CREATION OF THE
TETON LANDSCAPE_
The Geologic Story of
Grand Teton National Park
_By
J. D. LOVE AND JOHN C. REED, JR.
U.S. Geological Survey_
_Library of Congress Catalogue Card No._: 68-20628
_ISBN_ O-931895-08-1
1st Edition
1968
1st Revised Edition
1971
Reprinted 1979
Reprinted 1984
Reprinted 1989
Grand Teton Natural History Association
Moose, Wyoming 83012
CONTENTS
Foreword 6
THE STORY BEGINS 8
First questions, brief answers 9
An extraordinary story 10
An astronaut’s view 12
A pilot’s view 14
A motorist’s view 15
View north 15
View west 18
View south 19
A mountaineer’s view 20
CARVING THE RUGGED PEAKS 24
Steep mountain slopes—the perpetual battleground 24
Rock disintegration and gravitational movement 24
Running water cuts and carries 26
Glaciers scour and transport 28
Effects on Jackson Hole 30
MOUNTAIN UPLIFT 36
Kinds of mountains 36
Anatomy of faults 38
Time and rate of uplift 40
Why are mountains here? 41
The restless land 43
ENORMOUS TIME AND DYNAMIC EARTH 45
Framework of time 45
Rocks and relative age 45
Fossils and geologic time 46
Radioactive clocks 47
The yardstick of geologic time 48
PRECAMBRIAN ROCKS—THE CORE OF THE TETONS 51
Ancient gneisses and schists 51
Granite and pegmatite 55
Black dikes 58
Quartzite 63
A backward glance 64
The close of the Precambrian—end of the beginning 64
THE PALEOZOIC ERA—TIME OF LONG-VANISHED SEAS AND THE DEVELOPMENT
OF LIFE 66
The Paleozoic sequence 66
Alaska Basin—site of an outstanding rock and fossil record 66
Advance and retreat of Cambrian seas; an example 69
Younger Paleozoic formations 74
THE MESOZOIC—ERA OF TRANSITION 79
Colorful first Mesozoic strata 79
Drab Cretaceous strata 81
Birth of the Rocky Mountains 82
TERTIARY—TIME OF MAMMALS, MOUNTAINS, LAKES, AND VOLCANOES 86
Rise and burial of mountains 88
The first big lake 92
Development of mammals 95
Volcanoes 98
QUATERNARY—TIME OF ICE, MORE LAKES, AND CONTINUED CRUSTAL
DISTURBANCE 102
Hoback normal fault 103
Volcanic activity 103
Preglacial lakes 104
The Ice Age 105
Modern glaciers 112
THE PRESENT AND THE FUTURE 113
APPENDIX 115
Acknowledgements 115
Selected references—if you wish to read further 116
About the authors 117
Index of selected terms and features 118
_FOREWORD_
Geology is the science of the Earth—the study of the forces, processes,
and past life that not only shape our land but influence our daily lives
and our Nation’s welfare. This booklet, prepared by two members of the
U.S. Geological Survey, discusses how geologic phenomena are responsible
for the magnificent scenery of the Teton region.
Recognition of the complex geologic history of our Earth is vital to the
enjoyment and appreciation of beautiful landscapes and other natural
wonders, to the planning of our cities and highway systems, to the wise
use of our water supplies, to the study of earthquake and landslide
areas, to the never-ending search for new mineral deposits, and to the
conservation and development of our known natural resources. Who can
say, in the long run, which of the many uses of this knowledge is the
most compelling reason to seek an understanding of the Earth?
[Illustration: Signature]
W. T. Pecora, _Director_
U.S. Geological Survey
_This booklet is based on geologic investigations by the
U. S. Geological Survey in cooperation with the National Park Service,
U. S. Department of Interior._
“_Something hidden. Go and find it.
Go and look behind the Ranges—
Something lost behind the Ranges.
Lost and waiting for you. Go._”
KIPLING—_THE EXPLORER_