Physical Geology Review
what is a pluton
a body of igneous rock that slowly cooled from magma below the surface
the founder of modern geology
James Hutton
how was the age of the Earth determined
U/Pb radioactive isotope age dating on iron meteorites
actualism
what is speciation
the development of a new species
name the layers of the Earth and the physical state that they are
inner core (solid), outer core (liquid), mantle (solid), asthenosphere (plastic), crust (solid)
presented the idea of uniformitarianism
what does a young Earth suggest about the rate of geologic events?
super fast, catastrophic events
hypothesis
a testable statement about the way the natural world works that can be used to build more complex inferences and explanations (multiple working hypotheses encourage different kinds of observations)
what are 2 ways that a species could become isolated
mountain building event, rising sea level, continental rifting
describe geothermal heat
the Earths internal heat generated from radioactive decay (unstable isotope atoms decay/alter to daughter atoms)
used the theory of evolution to support a much older Earth
Charles Darwin
the Earth is...
(1) 4.567 hundred thousand years old
(2) 4.567 million years old
(3) 4.567 billion years old
(4) 4.567 trillion years old
(3) 4.567 Ga
evolutionary adaptive radiation
high rate of divergence (differentiation of characteristics) due to an opening of ecological niches (ex: after a mass extinction)
small, isolated, genetically less stable population with low preservation potential
allopatric population
describe a normal fault and the type of stress associated with it
hanging wall slides down, tensional stress
these 3 people attempted to use heat, sediment, and ocean salinity to (unsuccessfully) estimate the Earth's age
Charles Walcott, Lord Kelvin, Edmund Haley
how was sediment (incorrectly) used to estimate the Earth's age
Assumed a homogeneous rate of sedimentation (not true bc different environments) with no sediment to start with, like a blank slate. Also, sediment doesn't remain sediment forever and is removed from the system through erosion and unconformities.
theory
refers to a comprehensive explanation of some aspect of nature that is supported by a body of evidence (usually begins as a hypothesis)
i.e. the theory of gravity
describe gradualism
gradual change from one species to another; the only way to look at the rate of evolution on a genetic level
name 5 principles of relative dating
Law of Superposition
Law of Original Horizontality
Law of Lateral Continuity
Principle of Cross Cutting Relations
Principle of Inclusions
also could accept Principle of Faunal Succession
based on interpretations of the bible, assumed the Earth to be less that 6000 years old
Archbishop Ussher
the 4 assumptions used for U/Pb age dating
(1) steady rate of decay, (2) originally no Pb, (3) natural processes behave the same today as they always have in the past, (4) closed system
uniformitarianism
geologic processes observed today are assumed to have operated continuously throughout the past
describe punctuated evolution
abrupt appearance of a species in the rock record; an abrupt change in the forces driving natural selection, such as the environment, cause a migration of an allopatric species that then suddenly appear in the rock record