D-1 Review Questions

Question 1

What is the fundamental unit of biostratigraphy?

Answer 1

biozone

Question 2

Which of the following is NOT a type of interval biozone?

taxon-range biozone
concurrent range biozone
partial range biozone
acme biozone

Answer 2

acme biozone

The types of interval biozones are:
1. taxon-range biozone
2. concurrent range biozone
3. partial range biozone
4. lineage biozone (or consecutive range biozone)

Question 3

Which type of interval biozone uses two taxa with overlapping ranges?

Answer 3

concurrent range biozone

1. taxon-range biozone - single taxon
2. concurrent range biozone - two taxa overlapping
3. partial range biozone - two taxa not overlapping
4. lineage biozone - three or more taxa

Question 4

Which type of biozone uses an interval containing high proportion of a single taxon?

interval biozone
assemblage biozone
acme biozone
lineage biozone

Answer 4

acme biozone

1. interval biozone - succession of taxa
2. assemblage biozone - at least three related or unrelated taxa
3. acme biozone - abundance of single taxon

Question 5

What do you call the marine organisms that are free swimming?

Answer 5

nektonic

1. planktonic - free floating
2. nektonic - free swimming
3. benthonic - benthic or sea bed
4. sessile - attaching

Question 6

Which planktonic marine macrofossil is usually preserved as thin film having a teeth-like structure on fine grained sedimentary rocks?

Answer 6

graptolites

The common marine macrofossils are:
1. trilobites - arthropods, abundant in Cambrian
2. graptolites - teeth
3. brachiopods - shelly, sessile
4. ammonoids - cephalopods, includes goniatites and ammonites
5. gastropods - Mollusca, marine snails
6. echinoderms - includes crinoids (sea lilies) and echinoids (sea urchins)
7. corals

Question 7

Which marine microfossil are chrysophyte algae with a siliceous frustule?

radiolaria
coccoliths
diatoms
dinoflagellates

Answer 7

diatoms

The common microfossils are:
1. foraminifera - calcareous tests
2. radiolaria - silica skeletons, spherical and spiny
3. coccolith - spherical calcareous cysts
4. ostracods - crustaceans, calcareous carapace
5. diatoms - chrysophyte (golden) algae, siliceous frustule
6. conodonts - tooth-like, phosphate
7. acritarchs - spiny, related to dinoflagellates

Question 8

Which of the following microfossils DOES NOT have a siliceous skeleton?

radiolaria
diatoms
conodonts
none of the above

Answer 8

conodonts

The common microfossils are:
1. foraminifera - calcareous tests
2. radiolaria - silica skeletons, spherical and spiny
3. coccolith - spherical calcareous cysts
4. ostracods - crustaceans, calcareous carapace
5. diatoms - chrysophyte (golden) algae, siliceous frustule
6. conodonts - tooth-like, phosphate
7. acritarchs - spiny, related to dinoflagellates

Question 9

The half-life of a certain substance is 250 years. How many years does it take for the amount of a substance to be 1/16th of the original amount?

Answer 9

1000 years

1/16 = (1/2)^4 –> The substance underwent 4 half-lives –> 250x4 = 1000 years

Question 10

Which radiometric dating technique is most widely used in dating sedimentary strata because of the presence of the authigenic mineral glauconite?

Potassium-Argon
Rubidium-Strontium
Uranium-Lead
Samarium-Neodymium

Answer 10

Potassium-Argon

Common radiometric dating techniques:
1. Potassium-Argon - glauconite for sedimentary rocks, feldspars/micas - volcanic rocks
2. Rubidium-Strontium - igneous rocks, Rubidium is a trace element in silicates
3. Uranium-Lead - Uranium is found in zircon, monazite, sphene, and apatite – accessory minerals in igneous rocks
4. Samarium-Neodymium
5. Rhenium-Osmium

Question 11

Which of the following parent isotope has a half-life of 42 billion years?

Potassium - 40
Rubidium - 87
Rhenium - 187
Thorium - 232

Answer 11

Rhenium - 187

Common half-lives:
1. Potassium - 40 - 1.25 billion years
2. Rubidium - 87 - 48.8 billion years
3. Samarium - 147 - 1.06 billion years
4. Rhenium - 187 - 42 billion years
5. Thorium - 232 - 14.01 billion years
6. Uranium - 235 - 0.704 billion years
7. Uranium - 238 - 4.468 billion years
8. Carbon - 14 - 5730 years

Question 12

Which isotopic ratio can be used to determine the age of marine organisms made up of calcite?

Answer 12

86Sr/87Sr

Question 13

The Curie Temperature of Magnetite is 570 °C. What will happen to the magnetite present in a rock when it is heated above its Curie Temperature?

Answer 13

It loses its magnetic properties.

Above the Curie Temp, the magnetic alignment will be random. Not parallel nor opposite. Hence, the mineral loses its magnetic properties.

Question 14

Sampling of the ocean-floor sediments showed high 18O/16O ratio. This implies that these sediments were deposited during which type of climate?

Answer 14

cold climate

18O is heavier than 16O
1. warm climate - more 18O evaporates –> precipitates as ice in higher latitudes
2. cold climate - less 18O evaporates –> more 18O in oceans

Question 15

Which Milankovitch cycle have the longest period?

Answer 15

eccentricity

1. eccentricity - 100,000 years
2. obliquity - 40,000 years
3. precession - or wobble, 21,000 years

Question 16

Rift basis produce a series of fault-bounded blocks. What do you call the raised fault block?

Answer 16

horst

1. graben - g for ground –> so nasa baba
2. horst - h for high –> so nasa taas

Question 17

Which is a dome-shaped hill commonly produced by granite weathering?

Answer 17

bornhardts

1. bornhardts - dome-shaped hills
2. nubbins - or knolls, scattered blocks
3. castle koppies - small and angular

Question 18

Since the Philippines is located in the humid tropics which is characterized by intense leaching of soil, then by the scheme of Georges Pedro, it belongs to what weathering zone?

Answer 18

allitization zone

Georges Pedro’s weathering zones:
1. allitization zone - intense leaching, humid tropics
2. kaolinization - seasonal leaching, savannah
3. smectization - weak leaching, arid and temperate
4. little-chemical-weathering zone - deserts
5. podzolization zone - boreal
6. ice-cover zone - glacial

Question 19

When a river creates a canyon, we can assume that identical or similar strata on opposite sides once spanned the canyon. What principle best explains this?

Answer 19

Principle of Lateral Continuity

Question 20

Imagine that a series of sedimentary layers is deposited in a shallow marine setting. Then sea level falls, exposing some of the sedimentary layers. During this above-sea level time period, no new sediment accumulates, and some of the existing layers erode away. Later, sea level rises, resulting in the landscape becoming submerged once more. This causes a new series of sedimentary beds to be deposited. The boundary separating the two sets of beds is what type of unconformity?

Answer 20

Disconformity

1. angular - tilted or folded sedimentary rocks that are
   overlain by younger, more flat-lying strata
2. disconformity - erosion rather than deposition
3. nonconformity - sedimentary strata overlie older metamorphic or intrusive igneous rocks
4. paraconformity - no obvious erosional break

Question 21

A site where sediments and volcanic debris accumulate, which is located on the backside of a volcanic arc when viewed from the trench. In these regions, tensional forces tend to prevail, causing Earth’s crust to stretch and thin and resulting in the formation of a downfaulted basin. What is this region?

Answer 21

back-arc

Question 22

When a relatively cold, dense slab subducts, it does not follow a fixed path into the asthenosphere. Rather, it sinks vertically as it descends along an angled path. This causes the trench to retreat. What is the term to describe this mechanism?

Answer 22

trench rollback

Question 23

Joints profoundly affect the weathering of bedrock by allowing ion-rich water to penetrate to depth and start the weathering process long before the rock is exposed at Earth’s surface. The weathering of enlarged joints create long and narrow walls. What are these features called?

Answer 23

fins

Question 24

The slopes of many of the large normal faults in the Basin and Range Province decrease with depth and eventually join to form a low angle, nearly horizontal fault. What is this type of fault called?

Answer 24

detachment fault

Question 25

A boudinage forms when some portions of a rock body deform in a ductile fashion and others act as brittle units. What is the main factor that resulted in this type of deformation?

Answer 25

type of rock

Question 26

Like a spring, chemical bonds in a mineral grain stretch while under stress and then snap back to their original length. What type of deformation is this?

Answer 26

elastic deformation

Question 27

Because the sedimentary beds in basins usually slope at low angles, basins are identified mainly by the age sequence of their strata. What is the correct age sequence of basins?

Answer 27

youngest rocks are at the center and the oldest on the flanks

Question 28

It is estimated that the debris that rushed down the slopes of Peru’s Nevado Huascarán moved at speeds in excess of 200 kilometers per hour. What is this type of mass movement classified as?

Answer 28

avalanche

Question 29

Although they can occur in many different climate settings, they tend to occur more frequently in semiarid mountainous regions. Because of their fluid properties, they frequently follow canyons and stream channels. What is this type of mass movement?

Answer 29

debris flow

Question 30

When active landslides threaten infrastructure such as roads or buildings, geologists and engineers employ a variety of stabilizing methods. One of the methods is de-watering. Which is an example of this method?

Answer 30

installing horizontal drain pipes

Question 31

When soil is saturated with water, the soggy mass may flow downslope at a rate of a few millimeters or a few centimeters per day or per year. What is this type of mass movement?

Answer 31

solifluction

Question 32

A few hundred million years after the Big Bang, the primordial hydrogen and helium had condensed and coalesced to form the first stars and galaxies. Within the cores of these early stars, heating triggered the process of combining hydrogen nuclei to form helium nuclei, releasing enormous amounts of radiant energy. What is this process called?

Answer 32

nuclear fusion

Question 33

Chemical analysis of rock suggests that molecular oxygen began to appear in significant amounts in the atmosphere around 2.3 billion years ago, a phenomenon termed the Great Oxygenation Event. Which of the following is NOT a positive benefit of this event?

Answer 33

proliferation of anaerobic life forms

Question 34

he accretion of all of Earth’s major landmasses to form Pangaea spans more than 300 million years and resulted in the formation of several mountain belts. The collision of northern Europe with Greenland produced which mountain belt?

Answer 34

Caledonian Mountains

Question 35

Examples of this group include cycads, which resemble large pineapple plants; ginkgo trees, which have fan-shaped leaves; and the largest plants of the time, the conifers, whose modern descendants include pines, junipers, and redwoods. These dominated terrestrial ecosystems throughout much of the Mesozoic era, which lasted from 252 to 66 million years ago. What is this plant group called?

Answer 35

Gymnosperm

Question 36

Some reptiles evolved with specialized characteristics that allowed them to inhabit drastically different habitats. What group of reptiles became airborne?

Answer 36

pterosaurs

Question 37

Coasts may be classified by their changes relative to sea level. Emergent coasts are sites of either land uplift or sea-level fall. Which of the following is a feature of emergent coasts?

Answer 37

marine terraces

Question 38

In some wells, water rises, sometimes overflowing at the surface. What is this type of well called?

Answer 38

artesian

Question 39

When groundwater from hot springs and geysers flows out at the surface, material in solution is often precipitated, producing an accumulation of chemical sedimentary rock. What is deposited when the water contains dissolved silica?

Answer 39

geyserite

Question 40

At locations beyond approximately 100 degrees, Oldham observed that P and S waves were absent or very weak. Thus, he found evidence for the existence of?

Answer 40

inner core and outer core