quiz 5 Flashcards
which organisme first evolved during the cambrian explosion
trilobites
rock containing many of the earliest examples of evolving life are found in the …. of North america because they were formed in shallow …. seas
edges; epicontinental
the great oxygenation event occured -2.5 Ga and forced large amount of what to precipitate out of the ocean
banded iron formation
during the Hadean Eon earth surface was largely …..
molten and mafic
Stromatolites are layered structures produced by the activity of …..
cyanobacteria
earth is approximately how old?
4.57 billion years
the first supercontinent, Rodinia, formed at the end of the
Proterozoic
where would you go today if you wanted to see a piece of the earliest continental crust
canada
Continental crust was only able to form once Earth’s temperature had cooled enough for partial melting of the mantle to occur and produce basalt that was buoyant enough to stay afloat on the plastic mantle. Before this point in time small rafts of thin crust formed and remelted in a continuous cycle. What was the composition of these rafts?
ultramafic
During the Hadean Eon, Earth’s atmosphere is thought to have contained significant amounts of all but which pair (two) of the following gases: CO2, N2, NH3, PH3, SO2;
H20, CH4. O2
PH3, O2
The eon represented by abundant deposits of strata with shelly fossils is the
Phanerozoic
the Hadean was a time in earth history when
Earth’s interior was so hot and overturning so quickly that a solid outer crust was
quickly remelted
The Basin and Range Province of the SW United States comprises an alternating series of fault-block mountains and basins created by….. of the continent
extension
The most recent interval of Quaternary glaciation gave way to warmer, interglacial conditions about…. ago.
11 000 years
cells that have a nucleus are called … life
eukaryotic
The … occurred due to the creation of many new ecological niches that formed as a result of the breakup of the Rodinia supercontinent.
Cambrian explosion
tree sized relatives of the living ferns, club mosses, and scouring rushes were common in environement termed coal swamps during … period
carboniferous
true continental crust did not form until the … Eon, when Earth had finally cooled enough for protocontinents to form
Archean
how would you describe the banded iron formation
The BIFs show evidence of an oxygen-rich atmosphere that forced the oceans to become oxidizing and precipitate iron-oxide minerals. They are abundant at the beginning of the Proterozoic Eon.
rock chalk contains many of tiny algae shells and shrimp feces. this is evidence of which depositional envrionement
ocean
radinia and pangea are supercontinents that assembled during the … and …. respectively
Proterozoic; paleozoic
…. provides evidence of past life and thus help geologists understand how life and the envrionement changed thrughout earths history
fossils
80% of the mass of continental crust had formed by ?
early proterozoic
the himalayas were produced during the cenozoic by the colision of southern asia with ….
india
dinosaurs first appeared during the … period
triassic
the late heavy bombardement was a time during which earth was struck by many … which added … and kept the surface from cooling
meteorites and asteroids; heat
of the major orogenies that formed the appalachian mountains the … orogeny formed when Noth america and affrica collided
alleghanian
which eon saw the first single celled organisms
archean
why did banded iron formations form between 2.4 and 1.8 Ga
the oceans began to absorb large amounts of oxygen produced by cynaobacteria
