Founders of Historical Geology

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Founders of Historical Geology
Can be traced back to classical Greece
Nicolaus Steno (Neils Stensen) 1638-1687 Origina
lly a Danish physician An expert in
anatomy (Public Dissections) Developed the
fundamental principles of historical geology
Physician to the de Medici family in Florence
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Founders of Historical Geology
Nicolaus Steno (Neils Stensen) 1638-1687 In
1669, Steno wrote De solido intra solidum
naturaliter contento dissertationis
prodromus Prodromus to a dissertation on
Solids Naturally Enclosed in Solids only 78
pages long
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Founders of Historical Geology
Superposition - The scientific law stating that
in any unaltered sequence of rock strata, each
stratum is younger than the one beneath it and
older than the one above it, so that the youngest
stratum will be at the top of the sequence and
the oldest at the bottom.
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Founders of Historical Geology
With tilted beds, we need to consider
other sedimentary structures, like ripple
marks, mudcracks, graded bedding, geopetal
structures or cross-bedding to help
determine up direction. Can also use vesicles
in lava flows.
Superposition, cont.
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Founders of Historical Geology
Principle of Original Horizontality - The
scientific law stating that sediments settling
out of a fluid (air and water) are deposited
horizontally or nearly horizontally in layers
that lie parallel or nearly parallel to the
Earths surface.
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Founders of Historical Geology
Principle of Lateral Continuity - The scientific
law stating that as originally deposited, strata
extend in all directions until they terminate by
thinning at the margins of the basin,
end abruptly against some former barrier to
deposition, or grade laterally into a different
kind of sediment.
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Founders of Historical Geology
John Strachey 1671-1743 Used superposition and
original lateral continuity Determined the
stratigraphic succession of coals in
England Recognized what would later be termed
unconformities Performed local-scale
observations.
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Founders of Historical Geology
Giovanni Arduino 1714-1795 Had a broader global
view of sedimentary layers Developed the first
classification of rocks and relative
ages Primary Mountains crystalline
rocks oldest rocks on Earth later became
igneous/metamorph. Secondary
Mountains layered fossiliferous
rocks later sedimentary rocks Terti
ary unconsolidated sediments lava flows
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Founders of Historical Geology
Johann Lehmann 1719-1767 Georg Füchsel 1722-1776
Came up with classification similar to that of
Arduino Developed stratigraphic successions of
rocks in Thuringia, and the Hartz and Ertz
Mountains. Began to understand the events that
lead to mountain building
Lehmann
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Founders of Historical Geology
Peter Simon Pallas 1741-1811 Improved geologic
history of the mountains of Europe Developed the
general geologic history of the Urals Observed
changes in rock assemblages going from margins
to the core of mountains.
Reise durch verschiedene Provinzen des
Russischen Reiches 1771-1776 Journey
Through Several Provinces of the Russian Empire

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Founders of Historical Geology
Abraham Gottlieb Werner 1749-1817 Most
influential geologist of the late 18th
century Studied at the Freiburg Mining
Academy Taught mineralogy at Freiburg. Developed
the Neptunian classification of rocks All
rocks of the crust were deposited or
precipitated from sea water A universal ocean
once covered the Earth Followers called
Neptunists
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Founders of Historical Geology
Abraham Gottlieb Werner 1749-1817 Primitive
Rocks Deposited first Came from hot, steamy
fluid with many dissolved minerals Coarse
grained igneous and metamorphic Transition
Rocks Ocean basins formed, waters
cooled Fossiliferous, stratified
rocks Deformed rocks Ocean resembled modern
oceans
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Founders of Historical Geology
Flötzgebirge Flat lying sedimentary
rocks Contained lava flows Alluvium All
unconsolidated material
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Founders of Historical Geology
Where did all the water go?
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Founders of Historical Geology
James Hutton 1726-1797 Father of Modern
Geology Edinburgh physician geologist? Opponent
to Neptunism Believed fire was the
answer. Recognized change on the
Earths surface (Surficial processes were
active) Developed cyclic view of Earth No
vestige of a beginning, no prospect of an end.
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Founders of Historical Geology
Laid foundation for uniformitarianism The past
history of our globe must be explained by
what can be seen to be happening now. By
observing geologic processes in operation around
him, Hutton could infer the origin of features
observed in rocks. Present is the key to the
past. Archibald Geike 1835-1924
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Founders of Historical Geology
Geologic past has been different than
today Atmosphere Life Meteorite
Impacts Elevation of Continents Climate Rate
of change and intensity varied, but processes
are the same.
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Founders of Historical Geology
Actualism Natural laws governing both past and
present processes on Earth have been the
same. Hutton observed that for all the processes
to be active, immense time was
needed. Exploration of Siccar Point recognized
the vastness of time recognized unconformable
relationships in the rocks unable to determine
the age relationships.
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"The mind seemed to grow giddy by looking so far
into the abyss of time.".