GEOL110 Exam 2

Coal-bearing cyclothems were most common during which geologic period

Pennsylvanian

Of the "big 5" extinctions, the largest one was at the end of the:

Permian.

Plankton of the early to middle Paleozoic included which of the following

Radiolarians

A feldspar crystal in a sample of granite is subjected to potassium-40:argon-40 radioisotope analysis. 25% of the parent potassium-40 remains; 75% of the original sample has been converted over time to argon-40. How many half-lives have passed?

2

What is a vestigial structure?

A structure that serves no obvious purpose in an organism, but is shared in common with one (or more) different organisms as a result of sharing a common ancestor

What is a molase?

A wedge of terrestrial sediment specifically shed from uplifted mountains into the foreland basin

Which of the following orogenies resulted in the formation of the Old Red Sandstone continent

Acadian

Even if you found iridium associated with late Devonian mass extinction, which of the following besides impact could account for its concentration

Anoxia

To which phylum does this organism (Anomalocrais) belong?

Anthropoda

Why are beds of volcanic ash exceptionally useful for lithocorrelation in the field

Ash falls are deposited very rapidly (geologically speaking)

Phosphorus weathered from land earlier during the Proterozoic may have been sequestered (trapped) primarily in which type of rock

Banded iron formations

Which statement best describes the concepts of facies?

Similar environments exist at different times and different environments exist at the same time.

Which stable isotope (discussed in the text) is used as a marker for increased number of nutrient runoff (erosion) of the contents

Strontium

What sorts of evidence could you use to reconstruct the super continent Pannotia

Structural, Paleomagnetic, Lithologic

Ocean circulation patterns during the early-to-middle Paleozoic Era is thought to have resulted primarily from:

The production of warm, hypersaline water masses in shallow inland seaways

Most of the major phyla known today were present by the beginning or shortly after the beginning of the Phanerozoic

True

Enhanced marine photosynthesis during the late Ordovician is suggested by more positive _______ isotope values.

Carbon

Which mountains are remnants of the Acadian Orogeny?

Catskills

Conodonts likely belonged to which taxon?

Chordates

The eye of cephalopods and vertebrates is quite similar. Why

Convergent evolution

If you identified an uniformity at the boundary between two depositional sequences of sedimentary rocks, which type of uniformity would it most likely be?

Disconformity

New England and the mid-Atlantic regions of what is now the United States were impacted by both the Taconic and Acadian orogenies. Based on the current position of North America, the two directions below, in which direction would you predict the grade of metamorphism to increase

East

index fossils can sometimes provide time resolution down which level?

Epoch

Fossils such as fusulinids do not make good index fossils because they are so small

False

Swimming and deep burrowing are energetically inexpensive

False

Plants invaded terrestrial areas before animals. Plants evolved certain traits to survive and thrive on land in the Paleozoic. Which of these is NOT one of the plant traits that evolved in the Paleozoic?

Flowers: Angiosperms ("seed in a vessel") produced a flower containing male and/or female reproductive structures.

Of the following, which would probably be the most reliable for detecting that a limestone formation is actually two separate formations, separated by a paraconformity

Fragments from the lower formation reworked into the lower beds of the formation that have been incorporated into the top formation

Wings may have evolved in insects by

Hox genes and preadaptation

The Taconic "Alps" have been largely eroded away. What process helps to keep them eroding after they had formed?

Isostasy

When would you expect to find the first well-devolved soils based on the fossil record

Late Devonian

Glaciation definitely occured during which of these times

Late Ordovician

What is the primary reason to use igneous rocks for radiometric dating, rather than metamorphic rocks

Metamorphism "resets" the radioactive clock, so it can be impossible to tell if the radiometric date refers to the original metamorphism

With regard to ocean circulation and chemistry, which statement best characterizes Earth surface conditions as time moves from the middle Paleozoic to the late Paleozoic?

More rapid ocean circulation, higher oxygen levels (black shales less widespread), deepening CCD

Major animal taxa may have appeared during the Proterozoic-Phanerozoic transition in part because of:

Multiple Causation

Of the taxa below, which are typically not predators

Ostracoderms

Which came first

Ostracoderms

A rock contains abundant brachiopods and trepostome bryozoans. It mostly likely formed during which era?

Paleozoic

During which era were barrier reefs and atolls most widespread throughout North America

Paleozoic

During which era were barrier reefs and atolls most widespread throughout North America?

Paleozoic

What evidence would you look for in order to corroborate an impact during the late Devonian

Well-developed shock mineral assemblages, iridium, mircotektites

Which of the following has a high albedo

a white t-shirt, glacier ice

The dominant phytoplankton of the Proterozoic belonged to a group called

acritarchs

The Taconic "Alps" have been largely eroded away. What makes scientists think that they once existed?

all of these (Extensive igneous intrusions, Thick wedges of "molasse" following the intense igneous activity and metamorphism, Younger rocks thrust-faulted inland over older rocks, Intense regional metamorphism)

The spread of land plants likely had which of the following effects?

all of these (decrease of braided streams, diversification of land vertebrates, increased soil formation and soil profiles, possible stimulation of anoxia in late Devonian oceans as a result of increased weathering and nutrient runoff to the oceans)

The formation of Pangaea resulted in:

all of these (diverted ocean currents, vast continental interiors, the formation of large continental ice caps)

Which of these statements is true about the Blue Ridge Mountains?

all of these (represents rocks initialy formed during the Grenville Orogeny, represents rocks that were thrust-faulted over earlier Paleozoic rocks, runs from Georgia and Alabama into New England (as the "crystalline Appalchians"))

What is a cyclothem?

alternating stratigraphic sequences of marine and non-marine sediments

Nautiloids are most closely related to which group

ammonoid cephalopods

Vascular tissues confer strength on plant stems primarily because the cells contain:

cellulose

Stromatoporoid reefs were replaced in the Mississippian by:

crinoid meadows

In general, which of these conditions are associated with Icehouse Worlds

equatorial oceanic circulation is blocked by continental landmasses, low sea levels, conjoined continents or supercontinets, low co2 levels

All sailback reptiles belong to therapsids

false

Trepostome ("stony") bryozoans were replaced in the late Paleozoic by which groupduring the last half of the Paleozoic Era?

fenestrate bryozoans

All mollusks possess a muscular ______?

foot

Vertebrate jaws originated from

gill supports (arches)

The most likely cause of the late Ordovician extinctions is thought to have been:

glaciation and global cooling.

The limbs of labyrinthodonts and lobe-finned fish are examples of:

homologous structures

Brachiopods are characterized by their distinctive

lopophore (horseshoe-shaped, cilia-lined feeding structure)

large continental ice caps were located in the southern hemisphere during:

most of the carboniferous and permain, the late Ordovician

Anomalocaris may have been the first known __________ to be preserved in the fossil record

predator

Complete cycles of sea-level change (high to low and back to high again) associated with the tectonic cycle occur on approximately which duration?

several hundred million years

Sailback reptiles like Dimetrodon belong to the

synapids

By the late Paleozoic, the amniotes had diverged into several taxa. Amniotes lay their eggs on land or retain the fertilized egg within the mother, and are distinguished from the anamniotes, which typically lay their eggs in water. Modern amniotes include reptiles, birds, and mammals.But by the late Paleozoic, amniotes included the:*marine reptiles*Lepidosaurs: reptiles with overlapping scales*Archosaurs: amniotes with two holes in their skulls (diapsids)and.....

synapsids: animals with holes in their skulls under their eyes/cheekbones.

Therapsods eveloved from

synapsids: animals with skull-holes under their eyes/cheekbones

In order to use a fossil species as an index fossil, one must know:

the fossil's total range zone whenever it existed

you are investigating what you think is an ancient reef complex and find that structures consist mainly of the accumulations of the remains of fusulinids, brachiopods, crinoids, and other invertibrate taxa. You conclude that

the reefs were not "reefs" true-frame builders

The broad positive increase of carbon isotopes during the Permo-Carboniferous is thought to have resulted from:

the spread of coal swamps

Sponges do not possess true tissues

true

True or False: Oceanic gyres tend to be oligotrophic (nutrient-poor).

true

True or false: The formation of Pangaea resulted in greater climatic extremes on the Earth.

true

The remains of the Taconic Orogeny are found mainly in:

western Massachusetts and eastern New York state.