Download Powerpoint Presentation Physical Geology, 10th ed.

Welcome to Geology!
Warm-up for 8/7/15
1) Why do people study geology?
2) What are some topics we might
study?
Video Clip
• http://archives.aapg.org/k12resources/Geo
scienceExplained.cfm
WHAT IS D.E. GEOLOGY?
High School & Maricopa Community College Credit
Four Classes:
Semester 1:
a) Physical Geology Lecture (3cr)
b) Physical Geology Lab (1cr)
Semester 2:
c) Historical Geology Lecture (3cr)
d) Historical Geology Lab (1cr)
Credit transfers to ASU, UofA, and NAU.
TOPICS COVERED SEMESTER 1
-Minerals and Rocks
-Topographic Maps
-Landforms
-Groundwater
-Internal Processes
-Geologic Structures
-Geologic Hazards
-Economic Geology
TOPICS COVERED SEMESTER 2
-Formation of planets.
-Fossil identification.
-Paleoenvironments.
-Stratigraphy.
-Plate Tectonics.
-Reconstructing Earth history.
GRADING
PVCC REGISTRATION
• Registration deadline is August 27.
• Payment deadline is Sept 16 ($351).
Warmup
• How might Dual Enrollment expectations
differ from the expectations in a regular
classroom?
Classroom Procedures
• 1) Class begins with a Warmup. Write the
date, question, and your response.
• 2) Quiet symbol:
Classroom Procedures
• 3) Take care of personal needs before
coming to class (4 passes for sign-outs).
• 4) Leave your food and drink outside.
• 5) Cell phone policy.
• 6) Pick up graded papers in back of room.
• 7) Bell to bell learning.
INTRODUCTION TO
PHYSICAL GEOLOGY
Why is Geology Important?
Warmup: Continue listing ways
in which GEOLOGY relates to
this image.
Welcome to Geology!
How might a DE class differ from a
high school class?
1)
2)
3)
4)
5)
What is Physical Geology?
• Physical Geology is the study of
– 1) the materials that make up the Earth,
– 2) the changes that occur inside the Earth and
on Earth’s surface, and
– 3) the forces behind these changes.
WHAT IS PHYSICAL GEOLOGY?
• Geology is an interdisciplinary science (based on
chemistry, physics, and biology).
CHEMISTRY
PHYSICS
Geology
BIOLOGY
• Geology is an applied science, influencing almost
every aspect of our life.
Reasons to Study Geology
1) To Obtain Natural Resources.
For each American, we annually mine
22,000 pounds of mineral resources:
-Stone
-Sand
-Gravel
-Limestone
-Clay
-Salt
-Metals such as Iron, Aluminum,
Copper, Lead, Zinc, Manganese.
And 17,000 pounds of energy
resources:
- Petroleum
- Coal
- Natural gas
- Uranium
Most of these physical and
energy resources are nonrenewable. They take
thousands or millions of
years to form and
concentrate).
Warmup 8 /12
• Without looking at your notes,
• Sketch a Pencil, and list the ways geology
relates to your pencil.
2) To Protect the Environment
- Geologists study the movement of contaminants in
soil and groundwater.
3) To Understand Geologic Hazards
-Some parts of the world are more geologically active than
others.
-We can live in these areas if we understand the threats.
Flooding of the Mississippi River in 1993 resulted in 47 fatalities.
In Washington State, Mount St.
Helens erupted in 1980.
There were 57 direct fatalities (and
7 incidental fatalities).
The low death rate is a direct result
of predictions and warnings by the
USGS.
4) To appreciate our surroundings.
AZ REPUBLIC HEADLINES
8/12/14
The Earth's Four Systems
The Earth's Four Systems
The “spheres” interact. For example,
CO2 in the atmosphere is controlled by the
biosphere (plants absorb CO2 and animals
emit it), the geosphere (volcanoes release
CO2), and the hydrosphere (the ocean
absorbs CO2 and incorporates it into
limestone as the mineral calcite, CaCO3).
Warmup 8/14
Sketch the internal
structure of the Earth.
Earth’s Two Heat Engines
External
Internal
Weather and Weathering
Plate tectonics and Volcanism
Earth’s Structure
The Earth’s Chemical Layers
LAYER
THICKNESS (km)
CHARACTERISTICS
Crust
Oceanic crust: 5-10
km; Continental crust:
~33 km
Solid and made of light
elements. (Si,O,Al,Ca,K,Na)
2900 km
Plastic and made of heavier
elements.
(Si,O,Fe,Mg)
2270 km
Liquid and made of very
heavy elements.
(Fe, Ni)
1220 km
Solid and made of very heavy
elements.
(Fe,Ni)
Mantle
Outer
Core
Inner
Core
The Earth’s Mechanical Layers
1) Lithosphere: A cool, solid,
rigid layer made of crust
(oceanic and continental) and
the uppermost part of the
mantle.
Tectonics “plates” are made of
lithosphere.
2) Asthenosphere: A hot,
weak, plastic layer in the
upper mantle.
Tectonic plates "float" on the
plastic asthenosphere.
Important Note!
• The continents are not plates.
• Continents “ride” upon
plates, just like luggage rides
on a conveyer belt.
Warmup 8/15
Tell whether each process is linked to the
external or internal heat engine (or neither):
Mountain building
Meteorite impacts
Tsunamis
Winds
Tornados
Sinkholes
Earthquakes
Weathering
Flowing rivers
Tides
Rain
Plate tectonics
Continental Drift
• Continental Drift is a hypothesis proposed by German
scientist Alfred Wegener in 1920’s to explain the puzzlelike “fit of continents”, and the matching of rock and fossil
types across oceans.
• The hypothesis was largely rejected because the “driving
mechanism” was unknown.
Unifying Theme # 3:
Plate Tectonics
The theory of Plate Tectonics was proposed in the
late 1960s, largely in response to a new
understanding of seafloor geology.
The theory describes lithosphere as being broken
into plates that move slowly on top of the plastic
aesthenosphere.
This motion is driven by convection in the mantle
(hot buoyant magma rises and cooler, more dense
magma sinks).
Warmup
• What is the difference between “continental
drift” and “plate tectonics”?
• What do continental drift and plate tectonics
help us to understand?
The Plates and Plate Boundaries
There are 12 main lithosphere plates.
Much geology happens at the boundaries
between these plates!
Three Types of Plate Boundaries:
1) Transform Boundaries
2) Divergent Boundaries
3) Convergent Boundaries
Geologic Time
The best estimate for Earth's age is ~4.6 billion years (same as age of our
Solar System, as indicated by meteorites).
Historically, there has been much debate over "how fast" geology happens
with two different camps of thought:
CatastrophismUniformitarianism-
Today we know that many geologic processes occur gradually over
millions of years (such events are often imperceptible over the span of
a human lifetime), whereas some geologic events happen within
seconds.
Geologic Time
Define:
CatastrophismUniformitarianism-
Some Benchmark Events in Earth History
• The first life forms (bacteria) developed ~3.5
billion years ago (bya).
• Complex life forms first became abundant
about 544 million years ago (mya).
• Reptiles became abundant ~230 mya.
• Dinosaurs went extinct (along with many other
organisms) ~65 mya.
• Humans have lived for ~0.5 - 3 million years.