The Grand Canyon

1
The Grand Canyon

• By Ryan Arthur and Kole Patton

2
Brief Overview

• Throughout this chapter we will learn how to
  interpret the rock record of the Grand Canyon.
• We will learn how to explain how fossils can
  reveal the geologic history of the GC.

3
Vocab

• Outcrop- An exposed rock layer of any type.
• Vishnu SCHIST- Oldest rock in the GC.
• Tapeats Sandstone, Bright Angle Shale, Muav
  Limestone- All deposited during the Cambrian
  Period.
• Redwall Limestone-This rock represented the
  Mississippian Period.
• Supai Formation- Was deposited during the
  Pennsylvanian Period
• Hermit Shale, Coconino Sandstone, Toroweap
  Formation, and Kaibab Limestone- Represented the
  Permian Period.

4
History In Rocks

• Geologists can determine parts of the Earths
  history by observing the outcrops of the canyon
  walls.
• They can do this by following the law of
  Superposition.
• The geologists have found that the older the
  rocks, the farther down the cliff wall they will
  be. The younger the rocks, the further up the
  cliff wall they will be..(NO SCHIST)
• The bottom and the oldest rock in the canyon is
  Vishnu Schist.
• Tapeats Sandstone, Bright Angel Shale, Muav
  Limestone were all deposited during the Cambrian
  Period and make up the lover walls of the GC.
• Geologists believe that many of the periods
  between the Cambrian and the Mississippian
  Periods were eroded and worn away.
• They think that the Ordovician, Silurian, and
  Devonian periods were times of uplift and of
  great erosion in the canyon.
• The Mississippian Period was represented by
  Redwall Limestone. Redwall Limestone when the GC
  region was submerged under a shallow sea.
• The Supai Formation was deposited during the
  Pennsylvanian Period.
• The Permian Period was represented by the Hermit
  Shale, Coconino Sandstone, the Toroweap
  Formation, and the Kaibab Limestone.
• The Rocks labeled above make up the upper layers,
  or the newest rocks of the canyon.
• Kaibab Limestone is currently the very newest and
  the top of the Colorado Plateau.
• The Colorado Plateau is a part of the Grande
  Canyon(you dont have to write this bullet)
• All of the Schist above reveals more about the
  geologic history of the GC region.

5
History in Fossils

• Through radioactive dating geologists have
  estimated the age of the fossils found in the
  many rock layers of the Grand Canyon.
• The fossils are evidence of the kind of life that
  existed in those regions during the various
  periods.
• Limestone and Shale often contain fossils of
  marine organisms such as clams, fishes, and
  corals.
• The Bright Angle Shale contains many Trilobites,
  Marine Invertebrates, and Brachiopods.
• The fossils show that a distinctive group of
  animals lived during each period represented by
  the rock layers.
• Paleontologists can trace the changes in many of
  the organisms by examining the remains found in
  successive rock layers.
• Analysis of the fossils found in older and lower
  rock layers through the younger, upper layers
  suggests a sequence of events.
• These fossils indicate that early simple life
  forms gradually became either extinct or changed
  into more complex forms.
• The position, composition, and fossil content of
  the rocks in the GC.

6
The End

• This Project is made by Kole Patton and Ryan
  Arthur thanks to Ms .Gregory for giving us a good
  grade Please _