Geology 381 Midterm II-University of Calgary

Notice

If you get a question wrong, you can still click on the other answers. This will open up hints and explanations(if available) with additional information.

Disclaimer: While every reasonable effort is made to ensure that the information provided is accurate, no guarantees for the currency or accuracy of information are made. It takes several proof readings and rewrites to bring the quiz to an exceptional level. If you find an error, please contact me as soon as possible. Please indicate the question ID-Number or description because server may randomize the questions and answers.

Go to: Midterm I | Final

Geology (GLGY 381-UCAL) Midterm Exam II

Please wait while the activity loads.
If this activity does not load, try refreshing your browser. Also, this page requires javascript. Please visit using a browser with javascript enabled.

If loading fails, click here to try again

Some questions have hints and explanations. Click Start to begin.

Start

Congratulations - you have completed Geology (GLGY 381-UCAL) Midterm Exam II.

You scored %%SCORE%% out of %%TOTAL%%. With incorrect multiple attempts your score is %%PERCENTAGE%%

Your performance has been rated as %%RATING%%

Your answers are highlighted below.

Question 1

What type of environment would you expect to find this type of facies? (ID-SSM2-46)

A	wave dominated delta
B	tidal dominated delta
C	meandering river
D	braided river
E	alluvial fan
F	fluvial dominated delta

Question 2

What would you always expect to find in an alluvial fan? (ID-SSM2-18)

A	Overbanks
B	Avulsion
C	Extinct channels.
D	Tributaries
E	Distributaries

Question 3

When moving from A to B on the following flow chart (with respect to deltas), (ID-SSM2-52)

(A) Channels --> Levees --> Crevasse splay --> Floodplain (B)

A	the grain size decreases.
B	the grain size increases.
C	the density increases.
D	the density decreases.
E	the bioturbation decreases.

Question 4

What is the most common type of flow that contributes to the creation of alluvial fans? (ID-SSM2-22)

A	diagenesis flow
B	oscillatory flows
C	density flows
D	sediment-gravity flows

Question 5

On tidally dominated delta formations, lagoons can be identified by their fine grained mud (Fm) and/or rich organic content. (ID-SSM2-58)

A	True
B	False, that's a longitudinal bar.
C	False, that's a point bar.

Question 6

In general, rivers are stable systems. (ID-SSM2-54)

A	False
B	True

Question 7

Which of the following describe ooids? (ID-SSM2-65)

A	Fragments of calcium carbonate material that has been partly lithified.
B	Very fine grained material that precipitate by the breakdown of skeletal fragments.
C	Layers bound by cyanobacteria found as clasts within carbonate sediments.
D	Bodies of calcium carbonate less than 2mm in diameter and form by the precipitation of calcium carbonate.
E	Planktonic yellowgreen algae that are extremely important contributors to marine sediments.

Question 8

What is Eustasy? (ID-SSM2-31)

A	It is the term given to local base level of a fluvial system.
B	It is a drug that most geologists take to get high in the woods.
C	It is the term given to local sea level.
D	It is the term given to absolute sea level.

Question 9

What is the primary process that derive formation of rhizocretions? (ID-SSM2-88)

A	Gravity and pressure due to overburden sediment load
B	Fall of water table
C	Physical weathering
D	Rise of water table
E	Chemical weathering

Question 10

On the following diagram, the type of delta that would formed in section A is.... (ID-SSM2-40)

A	tidal dominated.
B	alluvial dominated.
C	fluvial dominated.
D	wave dominated.

Question 11

According to Dunham Classification, this type of rock has an extensive organic framework. (ID-SSM2-67)

A	Grainstone
B	Carbonate mudstone
C	Wackestone
D	Boundstone
E	Rudstone

Question 11 Explanation:

Some instructors do not require students to know this.

Question 12

Majority of modern day seawater is concentrated with which of the following ion? (ID-SSM2-69)

A	Calcium
B	Sodium
C	Potassium
D	Magnesium
E	Chlorine

Question 13

Inconsistent change in water level is the the primary driving force for meandering rivers. (ID-SSM2-35)

A	False
B	True

Question 13 Explanation:

Centrifugal force(F_c) is the the primary driving force for meandering rivers. While gravity also play a role, it is minor compared to F_c because the low-slope.

Question 14

When working on a scientific project,__A__ comes before__B__. (ID-SSM2-12)

A	A. interpretations B. observations
B	A. analysis B. observations
C	A. observations B. interpretations
D	A. observations B. analysis
E	A. alcohol B. dirty girls

Question 15

Bonus; Calgary Elbow River will fall under what type of river system? (ID-SSM2-59)

A	graded
B	braided
C	meandering
D	anastomosing

Question 16

Diagenesis is the process in which... (ID-SSM2-05)

A	soil created.
B	sediments get buried.
C	original horizontally changed due to a tectonic event.
D	grains transported to a new environment.

Question 16 Explanation:

To be clear; Diagenesis is the process of compaction and lithofication of sediments into sedimentary rocks.

Question 17

An oxbow lake most likely to be formed... (ID-SSM2-32)

A	near a meandering river.
B	in the anastomosing river.
C	near a braided river.
D	in a braided river.
E	in a high density flow dominated stream.

Question 18

The process which the pressure difference drives the water from cut bank to point bar is caused by... (ID-SSM2-44)

A	sediment accumulation.
B	gravitational force.
C	gravitational flow.
D	helicoidal flow.

Question 19

What type of flow is turbidity flow? (ID-SSM2-01)

A	Liquified Flow
B	Density Flow
C	Debris Flow
D	Sediment Gravity Flow

Question 20

Ogoki River hydro power dam in Ontario will result in___. (ID-SSM2-16)

A	rise in global base level.
B	fall in global base level.
C	fall in local base level.
D	rise in local base level.

Question 21

The process of compaction will result in... (choose the most suitable) (ID-SSM2-09)

A	reduce porosity causing beds to be thinner and dehydrated.
B	precipitation of minerals into the pore spaces reducing the porosity.
C	creates facies due to increase in temperature and pressure.
D	increase in volume as a direct result of increase in pressure due to burial.

Question 21 Explanation:

Few answers above can be considered as a right answers, but only one choice can be considered by technical definition.

Question 22

In lakes where sediment plumes and turbidity currents are the main transport mechanisms... (ID-SSM2-91)

A	deep lake facies will consist of very finely laminated muds deposited from suspension alternating with thin graded turbidites.
B	shallow lake facies will consist of very finely laminated muds deposited from suspension alternating with thin graded turbidites.
C	shallow lake facies will consist of alternating large scale muddy beds and sandy beds.
D	None of the answers are correct.
E	deep lake facies will consist of alternating large scale muddy beds and sandy beds.

Question 23

A fan delta is a depositional feature that is formed where an alluvial fan develops directly in a body of standing water(lake/ocean) as a result of streams originating from a steep environment. (ID-SSM2-23)

A	True
B	False

Question 24

Which direction a facies sequences can propagate? (ID-SSM2-29)

A	laterally left or right
B	vertically and laterally
C	vertically downwards
D	vertically upwards

Question 25

What is the difference between Calcite and Aragonite? (ID-SSM2-61)

A	Calcite has a different chemical properties than aragonite because calcite has an extra calcium ion.
B	Calcite has a trigonal crystal form, aragonite has an orthorhombic crystal form.
C	Calcite is calcium carbonate, CaCO₃ while aragonite is calcium magnesium carbonate, CaMg(CO₃)₂.
D	Calcite is calcium carbonate, CaCO₃ while aragonite is iron carbonate, FeCO₃.
E	Calcite is a carbonate mineral while aragonite is a silicate mineral.

Question 26

Large scale sandy deposits, important to the petroleum industry, are most likely to be found within which of the following river system sub-environments? (ID-SSM2-75)

A	Channels
B	Crevasse Splays
C	Floodplains
D	Levees

Question 27

Which of the following is the best possible location for a oil (petroleum) exploration? (ID-SSM2-73)

A	Older oxbow lake
B	Older point bar
C	Younger/modern river bed
D	Older alluvial fan
E	Younger/modern point bar

Question 28

Which of the following would increase the sediment accommodation space? (ID-SSM2-53)

A	increase in elevation
B	increase in sediment load Hint: this will decrease the accommodation space due to higher rate of sed accumulation.
C	uplift
D	subsidence

Question 29

Which of the following describe oncoids? (ID-SSM2-66)

A	Very fine grained material that precipitate by the breakdown of skeletal fragments.
B	Bodies of calcium carbonate less than 2mm in diameter and form by the precipitation of calcium carbonate.
C	Layers bound by cyanobacteria found as clasts within carbonate sediments.
D	Fragments of calcium carbonate material that has been partly lithified.
E	Planktonic yellowgreen algae that are extremely important contributors to marine sediments.

Question 30

How does large scale oxbow lakes get filled up by sediments? (ID-SSM2-80)

A	Collapse of sediments from overbanks.
B	Gravel deposits through biological activities in the surrounding area.
C	During a flooding event.
D	Development of soil form vegetation. Hint: Yes, but typically for smaller oxbow lakes.

Question 31

Choose all the correct statements. (more than one answer) (ID-SSM2-49)

A	point bar is an area of high erosion.
B	anastomosing rivers are avulsion dominated rivers.
C	imbricated clasts can be observed om gravel braided system.
D	ε cross beds form in the point bar side of a meandering river.
E	braided rivers are part of alluvial systems.

Question 32

Multiple interconnected channels are most likely to form within.... (ID-SSM2-78)

A	meandering rivers.
B	anastomosing rivers.
C	underwater fluvial deposits.
D	overbanks of lakes.

Question 33

Where do you expect the highest pressure on a meandering system? (ID-SSM2-51)

A	Near the point bar.
B	Shallowest part of the river.
C	Near the outer cut bank. Hint: aka outer bank
D	Floodplains on both sides of the river.

Question 33 Explanation:

This pressure difference result in helicoidal flow which cause erosion on the cut bank(aka outer bank) of the meandering system.

Question 34

What is flow expansion? (ID-SSM2-21)

A	Flow expansion is caused by increase in sediment load of the fluid flow.
B	Flow expansion is caused by increase in area of the fluid flow.
C	Flow expansion is caused by decrease in area of the fluid flow.
D	Flow expansion is caused by decrease in sediment load of the fluid flow.

Question 35

These type of fragments commonly found within limestone are faecal pellets of marine organisms such as gastropods. (ID-SSM2-64)

A	Oncoids
B	Pisoids
C	Peloids
D	Ooids

Question 36

What is the most common type of cements in nature? (ID-SSM2-07)

A	pyrite and calcite
B	silica and iron
C	silica and pyrite
D	calcite and silica

Question 37

Due to modern day global warming, the change in overall global sediment accommodation space has undergone.... (ID-SSM2-15)

A	regression
B	subsidence
C	transgression
D	base level increase
E	erosion

Question 38

Alluvial fans dominated by debris flows tend to form with __A__, while stream-flow dominated fans tend to form with __B__. (ID-SSM2-25)

A	A. steeper slopes in a wide area B. shallower slopes in a small area
B	A. steeper slopes in a small area B. shallower slopes in a small area
C	A. shallower slopes in a small area B. steeper slopes in a small area
D	A. steeper slopes in a small area B. shallower slopes in a wide area
E	A. shallower slopes in a small area B. steeper slopes in a wide area

Question 39

Which of the following is associated with lake turbidite deposits? (ID-SSM2-90)

A	Hypolimnion waters
B	Epilimnion waters
C	Thermocline waters
D	Oxic environment
E	Sediment load dominated by fine grains

Question 39 Explanation:

Hypolimnion = cold water and it is below the thermocline. It is also anoxic.

Question 40

A geological formation can have several lithofacies. (ID-SSM2-28)

A	True
B	False

Question 41

Chert is mostly composed of which of the following mineral? (ID-SSM2-72)

A	Apatite
B	Epsomite
C	Quartz
D	Glass
E	Halite

Question 42

How is Alizarin Red-S staining agent is used to identify dolomite? (ID-SSM2-62)

A	It will react with dolomite and stain it in green.
B	It will not stain dolomite but colours the other carbonates pink.
C	It will increase the relief by staining the dolomite grain boundaries.
D	It will stain dolomite red but will not stain the other carbonates.

Question 43

Turbidity flows can most likely occur in what kind of environment? (ID-SSM2-08)

A	areas with high friction
B	muddy rivers enter the lake
C	rivers with low sediment load
D	this question is stupid

Question 44

Sandy braided river systems will form __A__ and gravel braided rivers systems will form __B__. (ID-SSM2-56)

A	A. transverse bars B. longitudinal bars
B	A. unstable channels B. stable channels
C	A. levees B. point bars.
D	A. longitudinal bars B. transverse bars
E	A. stable channels B. unstable channels

Question 45

What is anhydrite? (ID-SSM2-70)

A	It is the dehydrated version of gypsum.
B	It is the fibrous mineral version of halite.
C	It is the dehydrated and fibrous version of sylvite.
D	It is a type of quartz that lacks water.
E	It is a type of precipitate occurs between grains of iron rich sediments.

Question 46

How is scars different from oxbow lakes? (ID-SSM2-33)

A	Scars are produced by braided rivers and oxbow lakes are produced by meandering rivers.
B	Scars are produced by anastomating rivers and oxbow lakes are produced by meandering rivers.
C	Scars and oxbow lakes are produced by meandering rivers. The difference is where oxbow lakes are filled with water.
D	They are the same thing, scars formed in dry-humid environment and oxbow lakes formed in wet environments.

Question 46 Explanation:

aka meandering scars

Question 47

Which type of alluvial fans most likely to preserve imbrication of clasts and up stream cross-stratification? (ID-SSM2-85)

A	Subaerial debris flows
B	Sheetflood deposition
C	Channel banks
D	Stream-channel fans

Question 48

Which of the following statement is true about facies and/or beds? (ID-SSM2-10)

A	Beds are composed of several facies.
B	A rock or lithologic unit that has consistent properties is known as a facies.
C	Facies only form in complex geologic environments.
D	Bed are vertical planer features resulted from recent geologic activities.

Question 49

What can be interpreted from presence of histosols in a core sample? (ID-SSM2-87)

A	This particular core section represents a channel bar deposit.
B	This particular core section must have been taken from the distal edge of a weave dominated delta deposit.
C	The area must have been enriched in organic matter.
D	The area must have been concentrated with poorly developed soil.
E	The area must have been arid.

Question 50

According the the classification of trace fossils based on interpretation of the activity of organism, which of the following is typically associated with crawling, gracing and feeding traces? (ID-SSM2-96)

A	Repichinia
B	Dominichnia
C	Fodinichina
D	Cubichina
E	Passichnia

Question 51

Which of the following is a characteristic of wave dominated delta? (ID-SSM2-84)

A	Large distributary channels developed well into the distal regions.
B	Flat or straight distal edge.
C	Increase in sediment accumulation towards the distal edge due to sandy deposits.
D	Lobe shaped bay fill towards the sea with a shape like a "bird's foot".

Question 52

Tidal inlets form under____ (pick the most suitable) (ID-SSM2-60)

A	high density flows.
B	low energy conditions.
C	high energy conditions.
D	low density flows.

Question 52 Explanation:

While density of the flow may play a role in how inlets in a tidally dominated deltas, it is the high energy condition drives the mechanism for the formation of inlets.

Question 53

On a sandy braided river system, the slip face would form on transverse bars on the.... (ID-SSM2-55)

A	upstream side.
B	left side in N. America and right side in Australia.
C	right side in N. America and left side in Australia.
D	left and right side, parallel to the flow.
E	downstream side.

Question 54

Cyanobacterial communities that have an irregular rather than layered form is known as... (ID-SSM2-63)

A	Stromatolites
B	Thrombolites
C	Stromatoporoids
D	Oncoids
E	Ahermatypic serpulids

Question 55

It is impossible to have a base level lower than the sea level. (ID-SSM2-14)

A	True
B	False

Question 55 Explanation:

Because the base level is actually the LOCAL lowest point in a river/lake. Imagine if you have a river 100s of km long and base level in can be lower than sea level in some area, but as long as gradient of the overall slope is downwards, the water will flow.

Question 56

Where can a sheetflood (sheet erosion) can be observed? (ID-SSM2-26)

A	debris flow dominated fans
B	stream-flow dominated fans
C	gradual erosional environments such as a beach/river bed.
D	poorly-sorted load dominated currents
E	all alluvial fans

Question 57

When you move from bottom to top in ideal turbidite Bouma sequence (A -> E), the flow velocity will... (ID-SSM2-03)

A	increase
B	decrease
C	None of the answers are correct because it could either increase or decrease depending on the environment.
D	fluctuate between high and low
E	remain consent

Question 58

As the amount of evaporation increases in lakes, the type of mineral precipitation varies. Which of the following has the correct order of mineral precipitation as lakes environment move from low evaporation to high evaporation? (ID-SSM2-94)

A	Gypsum - Sodium sulphates (eg. mirabilite) - Calcium carbonate - Halite
B	Calcium carbonate - Halite - Sodium sulphates (eg. mirabilite) - Gypsum
C	Gypsum - Calcium carbonate - Sodium sulphates (eg. mirabilite) - Halite
D	Calcium carbonate - Gypsum - Sodium sulphates (eg. mirabilite) - Halite
E	Calcium carbonate - Sodium sulphates (eg. mirabilite) - Gypsum - Halite

Question 59

Turbidity flows result in deposits known as turbidites. In the ideal turbidite sequence, where would you expect to find ripples? (ID-SSM2-02)

A	Section A; the first one from the bottom.
B	Section E; the fifth one from the bottom.
C	Section C; the third one from the bottom.
D	Section D; the fourth one from the bottom.
E	Section B; the second one from the bottom.

Question 60

Your job title is "Master of Exploitation of Natural Resources". If you were to search for hydro-carbons, which would be the best place to start(with the lowest cost to the company)? (ID-SSM2-27)

A	an alluvial fan
B	an oxbow lake
C	on a large vegetated point bar
D	on a river bed

Question 60 Explanation:

An oxbow lake is the best for coal formation. In general it takes less resources(both human and technological) to extract coal from an oxbow lake than extract oil from an alluvial fan. This question is testing your IQ. 🙂

Question 61

Where would you most likely to find palustrine environments? (ID-SSM2-92)

A	Within deep channels in a braided river system.
B	Lake margins with very gentle slopes.
C	At the mouth of rivers that carry large sediment load.
D	At the toe of wave dominated deltas with large scale muddy deposits.
E	Areas of mixing salt water with fresh water.

Question 62

On the following diagram, the type of delta that would formed at point 3 (blue) can be described as... (ID-SSM2-43)

A	wave energy based delta (smear)
B	tidal energy based delta (smear)
C	tidal energy based delta (bird's foot)
D	wave energy based delta (cupcake)

Question 63

Which of the following describes characteristics of floatstones according to Dunham Classification? (ID-SSM2-68)

A	Matrix supported with more than 10% grains.
B	Grain supported with some mud within the matrix.
C	Mud supported with more than 10% grains.
D	Mud supported with less than 10% grains.
E	Organic framework supported with original components organically bounded.

Question 63 Explanation:

Some instructors do not require students to know this.

Question 64

How large is the lateral width of a crevasse splay(generally)? (ID-SSM2-37)

A	It can varies widely between 10 of cms to 1000s of Kms depend on the environment.
B	10 of cms
C	100s of ms
D	1000s of Kms
E	100s of Kms

Question 65

Please the following items from bottom to top (aka, A to E) according to ideal Bouma sequence. (ID-SSM2-57)

1. normally graded bed (fining upwards)
2. silt and mud
3. ripples
4. lamination
5. fine lamination

A	2 (bottom) --> 4 --> 3 --> 5 --> 1 (top)
B	1 (bottom) --> 4 --> 5 --> 3 --> 2 (top)
C	3 (bottom) --> 4 --> 1 --> 2 --> 5 (top)
D	1 (bottom) --> 4 --> 3 --> 5 --> 2 (top)

Question 65 Explanation:

more info-external link

Question 66

Imbricated clasts often can be found in this type of system. (ID-SSM2-45)

A	gravel braided system.
B	tidal energy delta system.
C	wave energy delta system.
D	sandy braided system.

Question 67

If you have to identify the single most cause(while it is a combination of many) of alluvial fans formation, it would be... (ID-SSM2-17)

A	the change in base level.
B	the gain of energy(velocity) of the load bearing currents.
C	the change in elevation.
D	the loss of energy(velocity) of the load bearing currents.

Question 67 Explanation:

This is a tricky question... While several answers above can be right, the fundamental cause is the velocity change which in trigger density change causing deposition.

Question 68

Dedolomitisation result in which of the following? (ID-SSM2-76)

A	Increase the salinity of the groundwater.
B	Replacement of dolomite by anhydrites.
C	Calcium sulphate enrichment of groundwater.
D	Increase in the normal level of water table.
E	Decrease in the normal level of water table.

Question 69

Alluvial fan deposits are typically associated with ______ facies and rivers deposits are typically associated with ______ facies. (ID-SSM2-83)

A	ephemeral lake , estuarine
B	estuarine , sheet flood
C	delta , ephemeral lake
D	sheet flood , aeolian dunes

Question 70

What are Tufa or travertine? (ID-SSM2-93)

A	Clastic lake margin deposits.
B	Inorganic precipitate of calcium carbonate.
C	A type of sediment that was undergoing transition to coal from peat.
D	Organic precipitate of calcium carbonate.
E	Deep lake facies characterized by high concentrations of oncoids.

Question 71

Walther's law state... (ID-SSM2-30)

A	only beds with above 6 cm in thickness can be consider as a facies.
B	rise in sea level cause regression.
C	the vertical succession of facies reflects lateral changes in environment.
D	high energy currents can flow upstream, if the total energy of the current is higher than the gravitational gradient.

Question 71 Explanation:

Another way to state this would be; only those facies that were deposited side-by-side may be juxtaposed vertically.

Question 72

On the following diagram, the type of delta that would formed at point 2 (blue) can be described as... (ID-SSM2-42)

A	wave influx delta with a shape of a cupcake.
B	sediment impact delta with a shape of a bird's foot.
C	tidal flow delta with a shape of a cupcake.
D	wave influx delta with a shape of a bird's foot.

Question 73

What is cementation? (ID-SSM2-06)

A	Precipitation of minerals into the pore spaces increasing the porosity.
B	Addition of chemicals from outside of the strata into the pore spaces reducing the porosity.
C	Precipitation of minerals into the pore spaces reducing the porosity.
D	Addition of chemicals from outside of the strata into the pore spaces increasing the porosity.

Question 74

What is the best reasonable paleoenvironment interpretation for the following geological observations? (ID-SSM2-81)
-Several channels filled with sandy to muddy deposits
-Most of the channel fills overlaps each others
-Both vertically and laterally the channels are closer to each other

A	Must have been a submarine deposit channels within a large underwater deltaic environment.
B	River avulsion must have occurred with a much higher rate of channel fill and slow subsidence rate relative to the rate of overbank fill.
C	Several rivers must have been cut across the paleo flood plane at the same period of time, resulting multiple channels.
D	Sediment load must have been enriched in sand relative to muddy and other materials.
E	River avulsion must have occurred with a much lower rate of channel fill and higher subsidence rate relative to the rate of overbank fill.

Question 75

Which of the following describes Banded Iron Formations or BIFs? (ID-SSM2-74)

A	BIFs most likely formed in deep basins with very high iron rich organic sediment influx.
B	BIFs forms in modern environment, but at much smaller scale and rate.
C	Typically thin iron rich beds are composed of haematite rich sediments.
D	Iron within BIFs must have been oxidized before they were deposited as bands of thin beds.

Question 76

What is the process of transgressions? (ID-SSM2-13)

A	Seaward movement of the shore line often as a direct result of rise in sea level.
B	Landward movement of the shore line often as a direct result of rise in sea level.
C	Seaward movement of the shore line often as a direct result of drop in sea level.
D	Landward movement of the shore line often as a direct result of fall in sea level.

Question 77

Pedogenesis is caused by which of the following processes within sediments? (ID-SSM2-86)

A	Chemical and nuclear
B	Physical and chemical
C	Chemical and biological
D	Physical, chemical and biological
E	Chemical and mechanical

Question 78

A Professional Geologist have made the following observations: (ID-SSM2-24)
-active and extinct distributaries
-poorly sorted and mostly matrix supported
-reverse grading in basal section
-very steep surface with no vegetation
A possible environment for such observations could be....

A	high sediment load river bed
B	debris flow dominated fan
C	humid-desert extreme weather dominated river bed
D	stream flow dominated fan
E	low sediment load river bed

Question 79

On the following diagram, the type of delta that would formed in section B is.... (ID-SSM2-39)

A	tidal dominated.
B	alluvial dominated.
C	fluvial dominated.
D	wave dominated.

Question 80

Crevasse splays are deposits found in __A__ systems and generally have __B__ grains than flood plain facies. (ID-SSM2-36)

A	A. fluvial B. coarser
B	A. alluvial B. finer
C	A. fluvial B. finer
D	A. alluvial B. coarser

Question 81

Alluvial fans are differ from deltas because alluvial fans are formed as a direct result of flow expansion. (ID-SSM2-50)

A	False
B	True

Question 81 Explanation:

Both alluvial fans AND deltas are formed as a direct result of flow expansion. However, alluvial fans are deposited at the mouth of the canyon when it enters a low lying land while deltas are formed at the mouth of the river where a body of sediments deposited in a large body of standing water (ocean, lake).

Question 82

Where would you expect braided rivers to form? (ID-SSM2-79)

A	At low gradient slopes near the mouth of the river with low sediment load.
B	Between meandering section and the upstream of rivers with high sediment load.
C	Between meandering section and the upstream of rivers with low sediment load.
D	At low gradient slopes near the mouth of the river with high sediment load.

Question 83

This is an areal image taken in 1996 of a geologic feature in Skeidararsandur (Iceland). What is the best interpretation for this image? (ID-SSM2-48)

Copyrighted to Magnus Tumi Gumundsson and Finnur Palsson

A	Alluvial fan formed by a stream with high density sediment load
B	Delta formed due to hyperpycnal flow
C	Delta formed due to tidal flow
D	Delta formed due to hyperpycnal flow
E	Alluvial fan formed by a stream with heavy sediment load

Question 83 Explanation:

This is a difficult question, but a fair question.

Question 84

In alluvial fan transverse cross sections a geologist will___. (ID-SSM2-20)

A	observe a drop in base level moving downstream (negative change in slope).
B	observe a increase in base level moving downstream (positive change in slope).
C	observe an increase and then a decrease in base level moving downstream (like a bra cup).
D	observe a no change in base level or overall elevation since the sediments get deposited in a rapid rate.

Question 85

Which of the following characteristic of lake deposit is incorrect? (ID-SSM2-95)

A	Typically sands are moderately well sorted.
B	Very high degree of palaeocurrents preservation with extensive paleocurrent networks.
C	Often wave ripples and very fine parallel lamination are observed.
D	Dominated by sandstone, mudstone, fine-grained limestones and evaporites lithologies.
E	Facies an be best described as commonly occur with fluvial deposits, evaporites and associated with aeolian facies.

Question 85 Explanation:

The lake environments are relatively clam. Hence, development of palaeocurrents is very minimal and in most cases insignificant. While clam waters are good for preservation of sedimentary structures, palaeocurrents are not usually observed in lake type settings.

Question 86

Which of the following is indicative of phreatic zone sediments? (ID-SSM2-77)

A	Presence of globular masses of digenetic minerals within matrix.
B	Saturated zones of calcite within the matrix.
C	Isopachous cement between grains.
D	Complete dolomitisation.
E	Meniscus cements between grains.

Question 87

Meandering rivers most likely to formed in areas with... (ID-SSM2-34)

A	stable channels carrying a lose sediment load (such as sand/mud).
B	shallow unstable channels.
C	rivers with high width to depth ratio.
D	high gradient.
E	low gradient.

Question 87 Explanation:

Low gradient=low width to depth ratio. In some areas the difference is so small, it is harder for a Geologist to find the downstream direction (assuming river is not flowing).

While the meander is caused by several factors; the main factor is the low slope of the channel.

Question 88

A core sample can be exclusively used to identify the depositional environment with strong geologic constraints. (ID-SSM2-11)

A	False
B	True if the core penetrated across different strata.
C	True if the core is taken perpendicular to the natural depositional surfaces.
D	True if the core samples are taken within few lateral meters from each other.

Question 88 Explanation:

A core sample by itself cannot be used to identify the depositional environment. Several samples are needed to analyze the geological conditions in a given area.

Question 89

What are ephemeral lakes? (ID-SSM2-89)

A	Lake that are hydrologically closed and produce large deposits of precipitate minerals.
B	Lakes that are temporary bodies of water that exist for short periods of time.
C	Lakes that form in a volcanic crater or caldera.
D	Lakes with very high heat capacity hence able to reduce the temperate of the surrounding regions.

Question 90

______ is an important source of industrial potash that occurs associated with halite. (ID-SSM2-71)

A	Apatite
B	Selenite
C	Epsomite
D	Gypsum
E	Sylvite

Question 91

A Geologist noticed that Bouma sequence in the area only indicate deposition of lower units (ex A and B only). He/she is most likely at the... (ID-SSM2-04)

A	middle of the flow.
B	beginning of the flow.
C	end of flow.

Question 92

What is the difference between avulsion and migration? (ID-SSM2-38)

A	Avulsion and migration both caused by the rapid change of a river channel. But avulsion is found in braided rivers and migration found in meandering rivers.
B	Avulsion and migration both caused by the rapid change of a river channel. But migration is found in braided rivers and avulsion found in meandering rivers.
C	Migration is the rapid change of a river channel and usually caused by a sudden event such as a flood or an earthquake. Avulsion is the normal lateral motion of an alluvial river channel across its floodplain.
D	Avulsion is the rapid change of a river channel and usually caused by a sudden event such as a flood or an earthquake. Migration is the normal lateral motion of an alluvial river channel across its floodplain.

Question 93

The submarine delta deposits from when... (ID-SSM2-47)

A	density of effluent = density of the ambient
B	density of effluent < density of the ambient
C	density of effluent > density of the ambient Hint: aka hyperpycnal flow
D	density of effluent/density of the ambient = infinity

Question 93 Explanation:

Density of effluent (river water) is higher than the density of the ambient (sea water) causing river sediments to transport further and deposit in the ocean.

Question 94

Where can you find the apex of the alluvial fan? (ID-SSM2-19)

A	In the most expanded area.
B	Close to the canyon.
C	Close to an extinct channel.
D	Close to the lowest base level.

Question 94 Explanation:

Apex is the first point in which the flow expansion occur as a result of widening the area of flow.

Question 95

Typically what is the radius of debris flow alluvial fans? (ID-SSM2-82)

A	Less than 20 meters.
B	Hundreds of thousands of kilometers.
C	100s of meters to a few kilometers.
D	1 km to tens of kilometers.
E	One to ten kilometers.

Question 95 Explanation:

As a good Geologist, you should know the typical shapes and sizes for different types of alluvial fans. This will help identify different environments and improve geological interpretations.

Question 96

On the following diagram, the type of delta that would formed in section C is__I__ and these deltas become__II__. (ID-SSM2-41)

A	I. tidal dominated II. estuary
B	I. tidal dominated II. flood plains
C	I. tidal dominated II. flood plains
D	I. wave dominated II. estuary

Question 96 Explanation:

Estuary is an area which mixing of salt and fresh water can occur as a direct result of low slope and reverse(landwards) ocean tides.

Once you are finished, click the button below. Any items you have not completed will be marked incorrect. Get Results

There are 96 questions to complete.

←

List

→

Return

Shaded items are complete.

1	2	3	4	5
6	7	8	9	10
11	12	13	14	15
16	17	18	19	20
21	22	23	24	25
26	27	28	29	30
31	32	33	34	35
36	37	38	39	40
41	42	43	44	45
46	47	48	49	50
51	52	53	54	55
56	57	58	59	60
61	62	63	64	65
66	67	68	69	70
71	72	73	74	75
76	77	78	79	80
81	82	83	84	85
86	87	88	89	90
91	92	93	94	95
96	End

Return

Credits: Based on the excellent class notes provided by, Dr. Melissa Giovanni during Fall 2012. This version has been updated on between January and February 2016.
FAQ | Report an Error

My personal advice: Since the exams are written, if you score less than 90% on the following MC questions, seriously reconsider your study strategies for this class.

Sanuja Senanayake

Geology 381 Midterm II-University of Calgary

Go to: Midterm I | Final

Geology (GLGY 381-UCAL) Midterm Exam II

Some of the Lab Final sample images | Click here

Standing on the shoulders of giants

Go to: Midterm I | Final

Geology (GLGY 381-UCAL) Midterm Exam II

Some of the Lab Final sample images | Click here

Print/Share:

Standing on the shoulders of giants