Introduction to Earth History

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Lecture 2 Introduction to Earth History
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Outline
I Components of Geology A) Physical
Geology B) Historical Geology II Founders of
A) James Ussher B) Nicolaus
Steno 1) Superposition 2) Original
Horizontality 3) Original Lateral
Continuity C) John Strachey D) Giovanni
Arduino E) Abraham Gottlob Werner F) James
Hutton 1) Plutonism 2) Uniformitarianism
3) Hutton's Corollaries to Superposition a) Cr
oss-Cutting Relationships b) Inclusion G) Wi
lliam Smith H) Charles Lyell I) Charles
Darwin
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Geological Science
geology
the study of the planet Earth - the materials of
which it is made, the processes that act on these
materials, the products formed, and the history
of the planet and its life forms since its origin.
physical geology
a broad division of geology that concerns itself
with the processes and forces involved in the
inorganic evolution of the Earth and morphology,
and with its constituent minerals, rocks, magmas,
and core materials.
historical geology
a major branch of geology that is concerned with
the evolution of the Earth and its life forms
from its origins to the present day.
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Catastrophism
catastrophism
the doctrine that sudden violent, short-lived,
more or less worldwide events outside our present
experience or knowledge have greatly modified
the Earth's crust accounting for its present
configuration as well as for the observed
distribution of life forms.
James Ussher (1581-1656)
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Founders of Historical Geology Nicolaus Steno
(1638-1687)

• fossil descriptions
• first stratigrapher
• Steno's Laws

• Superposition
• Original Horizontality
• Original Lateral Continuity

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Steno's Laws Superposition
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Steno's Laws Original Horizontality
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Steno's Laws Original Lateral Continuity
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Founders of Historical Geology John Strachey
(1671-1743)

• local stratigraphy of English coal beds
• described first angular unconformity

an unconformity in which younger sediments rest
upon the eroded surface of tilted or folded
older rocks.
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Founders of Historical Geology Giovanni Arduino
(1714-1795)

• founder of stratigraphy
• Italian mines specialist

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Founders of Historical Geology Abraham Gottlob
Werner (1749-1817)

• mining inspector and teacher
• first to systematically classify minerals

Woodward (1733)
neptunism
the theory that the rocks of the Earth's crust
all consist of material deposited from, or
crystallized out of, water.
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Founders of Historical Geology Georges Leopold
Cuvier (1769-1832)

• founder of vertebrate paleontology
• scientific catastrophism

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Founders of Historical Geology William Smith
(1769-1839)

• first geologic map

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Principle of Faunal Succession

• Life on Earth has evolved through time.
• Therefore,
• Like assemblages of fossils are of like age, and,
• The rocks containing them are of like age

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Founders of Historical Geology James Hutton
(1726-1797)

• dynamic/cyclic concept of Earth history (rock
  cycle)
• plutonism
• deep time
• uniformitarianism
• recognized significance of unconformities
• corollaries to superposition

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Hutton's Rock Cycle
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Plutonism
the concept of the formation of the Earth by
solidification of a molten mass.
plutonism
Kircher (1655)
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Deep Time
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Uniformitarianism
the fundamental principle that geological
processes and natural laws now operating to
modify the Earth's crust have acted in much the
same manner and with essentially the same
intensity throughout geologic time, and that
past geologic events can be explained by forces
observable today "The present is the key to the
past." James Hutton (1726-1797)
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Hutton's Unconformities
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Hutton's Corollaries Cross-cutting Relationships
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Hutton's Corollaries Inclusions
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Founders of Historical Geology Charles Lyell
(1797-1875)

• first geologic time scale
• relative time

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Founders of Historical Geology Charles Darwin
(1809-1882)

• Evolution of Species through Natural Selection

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Components of Historical Geology

• geochronology
• paleoclimatology
• sea level
• stratigraphy
• plate tectonic movements
• paleontology

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General Patterns in Earth History
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General Patterns in Earth History Heat Flow

• Heat production 4 billion years ago was 4 to 6
  times as great as it is now

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General Patterns in Earth History Major Trends
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General Patterns in Earth History Atmospheric
Oxygen
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General Patterns in Earth History The History of
Life
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General Patterns in Earth History Biodiversity in
Earth History
Range of Global Biodiversity
Period
Era
QUATERNARY
CENOZOIC
TERTIARY
MASS EXTINCTION
CRETACEOUS
MESOZOIC
JURASSIC
MASS EXTINCTION
TRIASSIC
MASS EXTINCTION
PERMIAN
CARBONIFEROUS
MASS EXTINCTION
DEVONIAN
PALEOZOIC
SILURIAN
MASS EXTINCTION
ORDOVICIAN
CAMBRIAN
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General Patterns in Earth History Paleogeography
(Tectonics)
600 million years ago
300 million years ago
450 million years ago
today
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General Patterns in Earth History Climate
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General Patterns in Earth History Sea Level
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General Patterns in Earth History Summary