1. Geology 3
Field Assignment
By: Monica Royer
*Pictures are from my personal photo album

2. Yosemite

 The area that covers Yosemite National Park is 761,268 acres. It is located in
the Sierra Nevada mountain range. Each year there is more than 3.7 million
people that visit Yosemite. The national park is 95% wilderness.
 “The geology of the Yosemite area is characterized by granitic rocks and
remnants of older rock. About 10 million years ago, the Sierra Nevada was
uplifted and then tilted to form its relatively gentle western slopes and the
more dramatic eastern slopes. The uplift increased the steepness of stream
and river beds, resulting in formation of deep, narrow canyons. “
 “Archaeological findings have indicated that Yosemite Valley and other
areas presently within park boundaries have been inhabited by human
beings for over 4000 years. At the time the park area was first visited by
United States citizens in 1833 the area was inhabited by Miwok Indians
and periodically visited by Paiutes who lived east of the park in the Mono
Lake area.”
 http://www.shannontech.com/ParkVision/Yosemite/Yosemite.html
 http://en.wikipedia.org/wiki/Yosemite_National_Park

3. Formation of Yosemite
Valley

 “The area which now comprises Yosemite National park was
once covered by gentle, rolling hills. The Merced River flowed
through this valley fairly slowly. However, geological forces
pushed the hills and mountains higher and higher, and the
Merced River flowed more quickly and violently. It
increasingly cut a deeper, sharper, v-shaped valley through the
terrain. “
 “Several periods of glaciation caused major changes to the
valleys and landforms. Glaciers 2000 feet thick flowed through
the valley carved by the Merced. These glaciers carved away
the bottom of the valley from a V- to the broader U-shape
which is seen today.”
http://www.shannontech.com/ParkVision/Yosemite/Yosemite.html

4. Formation of Yosemite
Valley

 “At the end of the glacial period
the valley was actually much
deeper that what is seen today,
and a large body of water known
as Lake Yosemite covered it.
However, over a period of time
sediment accumulated in the
lake, filling it, and the existing
valley came into being. “
 The Tunnel View is one of the
first views of the valley that
people see.
http://www.shannontech.com/ParkVision/Yosemite/Yo
semite.html

5. Grizzly Giant

 The height of the tree is 209
feet, circumference is 96.5
feet, and basal diameter is
34.7 feet. It is estimated to be
3,800 years in age.
 Its looks to be one of the
most rugged and ripe tree in
the grove of giant sequoias.
 The sapwood and bark at
the base of the tree is 80%
consumed over from the
fires.
 The Grizzly Giant was first
documented around 1930.

6. Clothespin Tree

 The height of the tree is
266 feet tall.
 The fire burns the tree
received has left it with
an opening at the trunk
which makes it look
like a clothespin.
 The opening of the tree
is 70 feet high and 16
feet across.

7. Faithful Couple

 The East height of the tree
is 248 feet tall and the
West height of the tree is
also 248 feet tall and the
diameter is 19 feet.
 Many years ago they
were two separate trees.
Now the bases of the trees
are combined together.
 When the roots of one
tree absorbs water it can
be nutrition for the other
tree too.

8. Bridalveil Fall

 The height of the Fall is
620 feet.
 It is one of the few
waterfalls that flow
year-round. It keeps
flowing because it has a
more of a shaded
drainage.
 The Bridalveil Fall was
called “Pohono” by the
Native Americans.

9. Mule Deer
 Mule Deer got its name from
their ears that look like mule ears.
There ears are flattened to the
side when angry, and are laid
back against their neck when they
are hiding.
 In late May and early June the
fawns are born.
 The food they mostly eat is
leaves, twigs, and buds.
 Mule Deer Bucks use their antlers
for defending themselves and
during mating season.
 The deer protection from enemies
is by their running speed.

10. Half Dome

 The Half Dome is granite
which is igneous rock, and
more than 4,737 feet above
the valley floor rises the
crest.
 The age of the rock is 93
million years and the
Cretaceous period.
 The dome’s name was at one
time “Tis-sa-ack” and it is
the name of native women.
The face you can see in the
dome is known to be her
face.

11. El Capitan

 The El Capitan is mostly
made up of granite, which is
igneous rock. The age of the
rock is Cretaceous period.
 Sherwin Glaciation was the
main reason for the
sculpting of El Capitan, and
it lasted about 1.3 million
years ago to 1 million years
ago.
 From the base to the peak
the granite monolith rises
above 3,000 feet.

12. Yosemite National Park
Rock

 This rock in Yosemite is
an igneous rock.
 I believe it to be granite
like the Half Dome and
El Capitan. Also I
believe it is from the
Cretaceous period.
 Most of the rocks in
Yosemite are igneous
rocks and referred to as
granitic rocks.

13. References

 Bridalveil Fall. (n.d.). Retrieved from http://www.world-of-
waterfalls.com/yosemite-bridalveil-fall.html
 El Capitan. (2011, November). Retrieved from
http://en.wikipedia.org/wiki/El_Capitan
 Half Dome. (2011, November). Retrieved from
http://en.wikipedia.org/wiki/Half_Dome
 McFarland, J. (1949). A Guide to the Giant Sequoias of Yosemite National
Park. Retrieved from
http://www.yosemite.ca.us/library/sequoias_of_yosemite/tour.html
 The Mule Deer of Yosemite. (2010). Retrieved from
http://www.undiscovered-yosemite.com/mule-deer.html
 Yosemite National Park. (1994-2011). Retrieved from
http://www.shannontech.com/ParkVision/Yosemite/Yosemite.html
 Yosemite National Park. (2011, December). Retrieved from
http://en.wikipedia.org/wiki/Yosemite_National_Park