Quiz 3a Flashcards
(26 cards)
Shock metamorphism is most commonly found
Near impact craters
A mineral that forms at a restricted temperature and pressure is called
Index mineral
A foliated metamorphic rock with microscopic crystals, flat surgaces and a shiny luster is
Phylite
A black non foliated metamorphic rock that has undergone the highest grade of metamorphism is
Hornsfel
Pressure from all directions beneath the eath is called
Lithostatic
Blue schist facies metamorphism would indicate conditions of
High pressure and low temperature
The mineral that characterizes the green schist facies is
Chlorite
The meta morphic rock that usually forms as a result of contact metamorphismis
Hornsfel
The rocks contained in a formation must
have formed in the same enviorment
The era of “ancient life” is the
Paleozoic
The earlist period in the Paleozoic era is the
Cambrian
The earth formed about
4.5 billion years ago
The dinosaurs became extict
64 million years ago
In the remaining amount of radioactive element left in a mineral is only 1/16 of the original amount how many half-lives have gone by since the mineral formed
4
The parent isotope that is useful in determining the age of organic material that is a few thousand years old is
14C
40K decays to
40Ar
The key to sciendtific knowledge is that it must be
Based on repeatable observations and experiments
An included fragment of rock must be
Older than the rock that contains it
What type of unconformity has layers of sedimentary rocks over unlayered igneous or metamorphic rocks
Non conformity
The principle of uniformatarianism states
the present is the key to the past
The instrument used to determine the ages of samples by measuring tiny quantites of isotopes
Mass Spectrometer
When Sedimentary rocks are fist deposited they will
be in a horizontal layer
If a fault cuts across and moves a dike then
The fault must be younger than the dike
According to Archbishop Ussher’s annotations, the earth was created in
4004 BC
