Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
186 Cards in this Set
- Front
- Back
Define glacial. |
An interval of time (thousands of years) within an ice age that is marked by colder temperatures and glacier advances. |
|
Define interglacial. |
A period of warmer climate between glacial periods. We are currently living in the Holocene epoch, which is an interglacial. |
|
Define stadial. |
A period of lower temperatures during an interglacial (warm period) e.g. Little Ice Age |
|
What was the duration of the Wisconsin Glacial? |
110,000 years |
|
When did the Wisconsin Glacial peak? |
20-30,000 years ago |
|
When did the Wisconsin Glacial end? |
11,000 years ago |
|
What happened to the valleys in the cordillera during the Wisconsin Glacial? |
Valleys were buried under 1-2 km of ice. |
|
What landforms were created during the Wisconsin Glacial? |
Many of the U-shaped valleys |
|
When did the holocene interglacial begin? |
11,000 years ago |
|
When did the Little Ice Age stadial end in the southern canadian rockies? |
About 1840AD |
|
What period are we currently in? |
In an Ice Age, in Holocene Interglacial |
|
What period did we just come out of? |
Little Ice Age stadial |
|
What happens to the sea level when glaciers grow? When glaciers melt? |
When glaciers grow, sea levels fall. When glaciers melt, sea levels rise. |
|
What was the continental shelf like during the last Ice Age? |
The continental shelf was dry. |
|
What would happen to the coastline if present-day ice sheets were to melt? |
The coastline would flood. |
|
Prehistoric people migrated across what bridge? |
The Bering Strait Land Bridge |
|
When did sea levels rise? |
Between 17,000 and 7,000 B.C.E. |
|
What kind of valley would you see at Kananaskis Valley, Peter Lougheed Provincial Park? |
U-shaped valley |
|
What kind of glacial deposit would you find at Emerald Glacier, President Rang, Yoho National Park? |
Moraines. |
|
What would you find at Columbia Icefield, Athabasca Glacier? |
Holocene glaciation. |
|
Where would you find evidence of receding ice? |
At Athabasca Glacier |
|
What is the vertical deflation of Athabasca glacier? What is the toe recession? |
Vertical deflation: 6m/year Toe recession: 10m/year |
|
What are erosional features? |
Sculpting of the mountains. |
|
What are glacial deposits? |
Layers of sediment moved by glacial activity. |
|
What can you say about ice crystal size in relation to burial depth? |
Crystal sizes increase with depth. |
|
What are the five types of snow/ice, from most shallow to deepest? |
Loose Snow Granular Snow Firn Fine-Grained Ice Coarse-Grained Ice |
|
What percentage of air is in each of the types of snow/ice? Are bubbles present in any? |
Loose Snow: 90% air Granular Snow: 50% air Firn: 25% air Fine-Grained Ice: <20% air, in bubbles Coarse-Grained Ice: <20% air, in bubbles |
|
At what depth would you find Firn? At what depth would you find Coarse-Grained Ice? How old would each be? |
Firn: 10,000 years, 250m
Coarse-Grained Ice: 130,000 years, 2000m |
|
How does glacial ice move? |
The lower layers of glacial ice flow and deform plastically under the pressure, allowing the glacier as a whole to move slowly like a viscous fluid. |
|
What is ablation? |
Refers to melting, runoff, evaporation or sublimation of the ice, resulting in a thinning of the ice if it is not replenished by some other process. |
|
What is sublimation? |
Transformation from solid to gaseous state. |
|
Glacial waters contain rock flour. What is rock flour? |
An extremely fine powder ground from the underlying rock by the glacier's movement. |
|
What are glacial moraines composed of? |
They are usually composed of linear mounds of till, a non-sorted mixture of rock, gravel |
|
How are glacial moraines deposited? |
The till is deposited directly by the glacier as it erodes rocks that it passes over. |
|
What is a drumlin? |
An elongated whale-shaped hill formed by glacial action. |
|
How can you tell which way the glacier was moving by looking at the drumlin? |
Its long axis is parallel with the movement of the ice, with the blunter end facing into the glacial movement. |
|
How tall can drumlins be? How long? |
Drumlins may be more than 140 ft high |
|
Where are drumlins often found? |
Drumlins are often found in drumlin fields of similarly shaped, sized and oriented hills. |
|
What are the two theories as to why drumlins form? |
1. Direct formation of the ice 2. Catastrophic flooding underneath the glacial ice |
|
When does abrasion occur? |
Occurs when the ice and the load of rock fragments slide over the bedrock and function as sandpaper that smooths and polishes the surface situated below. |
|
What are the three causes of ice ages? |
1. Eccentricity (earth's orbit more oval than circular) 2. Tilt (of axis of rotation) 3. Precession (wobble of axis) |
|
What can be said about the trend of Earth's climate? |
Climate on Earth changes naturally. We have had warmer and cooler time periods even since the end of the last glacial. |
|
Following questions are on Highland Valley Copper Mining... |
... |
|
1. How many L of water does the mine use per minute? |
200,000L/min |
|
2. What are they two main metals produced at the mine? |
Cu, Mo |
|
3. What percent of the water used at the mine is recycled? |
80% |
|
4. How many pits are currently in operation? |
Three |
|
How deep is the current pit? |
500m |
|
How many years has the mine been in operation? |
45 years |
|
How big is a typical blast area? |
Football field size |
|
How much does a mine truck cost? |
$3 million |
|
Where do most of the metal concentrates get shipped to? |
Vancouver and Asia (to the west), the remaining 20% goes to Eastern Canada. |
|
What does porphyritic mean? |
Igneous texture with large and small minerals |
|
What type of elements make up porphyry? |
Cu (Au, Mo, Ag) |
|
Where do highland valley copper ore deposits typically occur? |
Beneath volcanoes in subduction-related, continental-arc, and island-arc settings. |
|
What are the four ore forming processes? |
Magmatic Hydrothermal Sedimentary Metamorphic |
|
Define magmatic. |
Crystallization and settling from magma |
|
Define hydrothermal. |
Heated groundwater transports and concentrates elements e.g. porphyry copper (Highland Valley) |
|
Define sedimentary. |
Weathering, transport, deposition |
|
Define metamorphic. |
Growth of minerals from chemical reactions |
|
Metallic minerals crystallize directly from magma containing which elements? |
Platinum Gold Nickel |
|
Describe how hydrothermal deposits occur. |
Circulating magmatic (hydrothermal) fluids concentrate and redistribute elements (Copper, Zinc, Gold, Iron) |
|
What two important things do igneous rocks provide? |
Heat Source of metal |
|
What is a Placer Deposit? |
An accumulation of valuable minerals formed by deposition of dense mineral phases in a trap site. |
|
Where does the word "placer" come from? |
The name is from the Spanish word placer, meaning "alluvial sand". |
|
What mineral would you find in a contact metamorphism zone? |
Ca-rich wollastonite mineral |
|
Where do skarns occur? |
The skarn occurs where fluids emitted from the cooling igneous rock interact with the surrounding limestone. |
|
In which belt would you look for metals such as gold, copper, lead, zinc, and molybdenite? |
come back to |
|
In which belt would you look for rock such as granite, sandstone, pumice, and shale? |
come back to |
|
In which belt would you look for fossil fuels such as oil, gas, and coal? |
come back to |
|
In which belt would you look for gravel and sand? |
come back to |
|
In order to find an ore deposit, what materials should you be looking for? |
Metals, minerals, rocks |
|
When looking for an ore deposit, what features would you include in a geological map? |
Igneous rocks, metamorphic rocks, fault zones, veins |
|
When looking for an ore deposit, what are some clues you should look for? |
Indicator minerals (till and sediment), rusty zones, faults and fractures. |
|
How would you determine if extraction of an ore deposit is feasible? |
Grade of ore, presence of roads and infrastructure. |
|
What place in Canada has become one of the world's major mining regions? When did it begin? |
Coal mines on Vancouver Island Placer gold camps of the Cariboo, British Columbia Beginning in the mid-1800s. |
|
British Columbia is an important producer and exporter of what materials? |
Copper, gold, silver, lead, zinc, molybdenum, coal and industrial minerals. |
|
What are the three main fossil fuels? |
Coal, oil, natural gas |
|
What are the necessary conditions for the production of fossil fuels? |
1. Sedimentary rocks rich in carbon/organic material
2. Proper pressure-temperature conditions |
|
How is coal accumulated? |
Through the accumulation of buried plants. |
|
How does oil and gas accumulate? |
Death, burial, and accumulation of organic material (sea floor) resulting in transformation to oil and gas source rock. |
|
Describe the first of four stages of oil and gas formation. Include temperature and conditions. |
1. Plankton and clay floating in water sink and accumulate. Temperature of plankton and clay about 5 degrees. Water poor in oxygen. |
|
Describe the second of four stages of oil and gas formation. Include temperature and conditions. |
2. More sediment accumulates over plankton-rich layer and compresses it. Temperature of plankton about 15 degrees now. |
|
Describe the third of four stages of oil and gas formation. Include temperature and conditions. |
3. Organic-rich mud turns to black shale. Under heat and pressure, kerogen forms. Now at 80 degrees. |
|
Describe the fourth and final stage of oil and gas formation. Include temperature and conditions. |
As temperature increases, kerogen turns to oil. Oil rises. Temperature about 120 degrees. |
|
What is the oil window? |
The range of temperature conditions and depth at which hydrocarbons form. Specific T range for oil formation. |
|
Where would you find the natural gas window in relation to the oil window? |
Natural gas window at greater temperature and depth than the oil window. |
|
What do you find after the oil and gas window? |
Graphite |
|
What is surface geology in respect to searching for hydrocarbons? |
Looking at rock type and extent |
|
What is subsurface imaging (geophysics) in respect to hydrocarbon searching? |
The use of drilling wells and seismic surveys |
|
What is the source rock you would find when searching for oil and gas in the cordillera? |
Carbon-rich shales |
|
What are the reservoir rocks you would find when searching for oil and gas in the cordillera? |
Fractured and permeable cretaceous sandstone and paleozoic limestone |
|
On what belt would you find structural traps? |
Foreland fold and thrust belt |
|
In what belt(s) would you find natural gas? |
Foreland fold and thrust belt (foothills) |
|
In what belt(s) would you find coal? |
Foreland Fold and Thrust Insular Intermontane |
|
What is the birthplace of Alberta's oil and gas industry? |
Turner Valley |
|
What was the name of the first well in Alberta? |
Dingman #1 Well |
|
When did the Dingman Discovery well blow? |
On May 14, 1914 |
|
For how many years was the Turner Valley Oilfield the largest oil and gas producer in the British Empire? |
For 30 years |
|
Where would you find coal in the cordillera (structure and time period)? What can you say about the appearance of the structure? |
In sedimentary basins (Jurassic and younger)
Structurally deformed |
|
What is unique about methane gas reservoirs? |
Unlike conventional gas reservoirs, methane is adsorbed onto the coal seam 'reservoir.' The coal is both the reservoir and source rock for methane. |
|
What is a pyroclastic eruption? |
Explosive eruption |
|
What is an effusive eruption? |
Lava flow |
|
What are the 3 main types of eruptive material? |
Lava, ash, bomb |
|
What are the volcano types in the cordillera? |
Composite volcanoes Shield Volcanoes |
|
What is an example of a composite volcano in the cordillera? |
Mt. Garibaldi, Garibaldi / Pemberton Belt |
|
What is an example of a shield volcano in the cordillera? |
Anahim Volcanic Belt, central BC |
|
What is an example of a cinder cone in the cordillera? |
Williams Cone, Northern Cordillera Volcanic Province |
|
What is an example of a tuya in the cordillera? |
Hoodoo Mountain, Northern Cordillera Volcanic Province |
|
In the cordillera, how many potentially active volcanoes are there? |
Potentially 200 |
|
How many volcanoes have been recently active in the cordillera? |
49 |
|
How many volcanoes have associated seismic activity since 1975? |
9 |
|
What make up the degree of hazards of volcanic eruptions in the cordillera? |
Intensity of eruption Duration Area affected |
|
What is the concern about our water supply in the event of a volcanic eruption? |
Water contamination |
|
What kinds of mass wasting are hazards in the event of a volcanic eruption? |
Lahars Rock slides |
|
How do you model volcanic eruptions? What are examples? |
Based on past volcanic eruptions: Geologic past (i.e. Mt. Meager) Recent past (i.e. Mt. St. Helens)
Example – Mt. Cayley eruption (Garibaldi Volcanic Belt) |
|
When was Mount Meager's last explosive eruption? |
2350 b.p. |
|
What evidence can you still see of Mount Meager's explosive eruption? |
Pyroclastic deposit |
|
In modelling a volcanic scenario of Mount Cayley, what would be some indicators pre-eruption? |
Increased seismic activity Hotspring changes Development of fumaroles Land surface changes |
|
In modelling a volcanic scenario of Mount Cayley, what would happen during the eruptive phase? |
Sustained eruption (12 hrs) Spread of ash Collapse of ash column (pyroclastic flows) Lahars |
|
In modelling a volcanic scenario of Mount Cayley, what would happen post-eruption? |
Small eruptions (local extent) Lahars |
|
What are lava flows? What is their flow rate? |
Consist of magma flowing along the Earth’s surface (basalt, andesite and rhyolite)
Flow rates cm/hour to few km/hr |
|
What is pyroclastic flow? What is its flow rate? |
Pyroclastic flow is an avalanche of hot ash and pumice and rock fragments (pyroclasts), and volcanic gases, cools and welds together after deposited on surface
Flow rates > 100 km/hr |
|
What does basalt look like? (grain size and colour) |
Very fine-grained Black |
|
Where would you find basalt lava? |
Hawaii, Iceland, mid-ocean ridges. |
|
A lava flow develops from: A. Slow moving sticky lava B. Fast moving runny lava C. Pyroclastic eruptions D. Eruption under water |
A. Slow moving sticky lava |
|
Vesicular texture is produced when ___________ get trapped as lava solidifies into solid rock. A. Crystals B. Bubbles C. Xenoliths |
B. Bubbles |
|
In igneous rocks, xenoliths are:
A. Clusters of crystal that formed after eruption B. Rocks erupted by a volcano |
C. Foreign rock fragments |
|
What was Canada's worst known volcanic disaster? |
Tseax Volcano eruption |
|
Where is the Tseax Volcano located? |
It is located 60 kilometres (37 mi) north of Terrace, British Columbia. |
|
How can you identify the Tseax Volcano? (i.e. volcano type, flow type, association) |
A young cinder cone and adjacent basalt lava flows associated with the Northern Cordilleran Volcanic Province |
|
When did Tseax erupt? |
1775 |
|
How long are the basalt lava flows at Tseax volcano? |
22.5 km basalt lava flow |
|
Which group of people were affected by the Tseax volcano eruption? What amount their of land did it destruct? |
The Nisga'a people Two villages |
|
Approximately how many people died in the Tseax eruption? Due to what? |
Approximately 2,000 Nisga'a people died due to volcanic gases and poisonous smoke (most likely asphyxiation by carbon dioxide). |
|
What is the composition of cinder cones? |
Eruptions of basaltic composition, spattering |
|
What are the features of cinder cones? |
Steep sided slopes, smallest of volcano types Flanks of shield volcanoes |
|
What composition of magma has been erupted to form the cinder cones of the San Francisco Volcanic Field? A. Ultramafic B. Mafic C. Intermediate D. Felsic |
B. Mafic |
|
True or False: A cinder cone records a long history of volcanic activity because it is a long-lived feature, forming over many eruptions from the same eruptive vent. |
False |
|
What type of volcano is the Nazko Volcano? Is it active or dormant? |
A small potentially active basaltic cinder cone |
|
Where is the Nazko Volcano? |
In central British Columbia, 150 kilometers southwest of Prince George. |
|
What belt is the Nazko volcano considered to be in? |
It is considered the easternmost volcano in the Anahim Volcanic Belt. |
|
How long has the Nazko volcano displayed volcanic activity? |
340,000 yrs to recent |
|
When was the lat eruption at Nazko? What did it consist of? |
7200 B.P. Lava flows + small explosive eruptions |
|
What happened at Nazko in 2007? |
In 2007, a small swarm of earthquakes occurred 20 km west of Nazko Cone. |
|
What were the magnitude of the earthquakes at Nazko in 2007? |
Most of these earthquakes were magnitude 1.0 or less. |
|
What was the cause of seismic activity at Nazko in 2007? |
The cause of this seismic activity is believed to be the upwelling of magma because the area is not close to any faults or plate boundaries. |
|
What economic advantage did Nazko possess in the early 1990s? By whom was it utilized? |
Was staked for mining its cinder and scoria in the early 1990s by the Canadian Pumice Corporation. |
|
What has Nazko produced? Has is been reduced? |
Been steadily reduced to produce red industrial aggregate for landscaping. |
|
What kind of magma do you find with strato (composite) volcanoes? |
Andesitic and rhyolite magma dominant, basalt subordinate |
|
What does a composite volcano look like? |
Steep-sided, cone-shaped Alternating layers of lava and pyroclastic material |
|
With which plate-tectonic environment are stratovolcanoes most commonly associated? A. Continent-continent collision zones B. Subduction zones C. Mid-ocean ridges |
B. Subduction zones |
|
What triggers the magmatism that leads to the development of volcanic arcs near subduction zones? A. Frictional heating of the non-subducting plate B. Melting of the subducted oceanic crust |
D. Addition of water into the upper mantle |
|
Which of the eruptive conditions listed below is most appropriate to the formation of stratovolcanoes? A. Relatively non-explosive eruption of fluid mafic lava flows B. Intermediate composition pyroclastic eruptions and lava flows |
B. Intermediate composition pyroclastic eruptions and lava flows |
|
What are earthquakes? |
Earthquakes are shock waves or, in other words, vibrations within the Earth. |
|
How are earthquakes triggered? |
They are triggered by the sudden slippage of rock along fault planes in the crust or mantle. |
|
What is the cause of earthquakes? |
Cause: release of accumulated stress. |
|
What are seismic waves? |
The energy released during earthquakes pulverizes rocks, generates heat, and causes vibrations. |
|
At what point do earthquakes originate? |
At the earthquake focus. |
|
Where is the earthquake focus? |
Directly below the epicentre. |
|
What is the epicentre? |
Point on the surface of the earth above the focus. |
|
What are the two types of seismic waves? |
Body waves and Surface waves |
|
Body waves can be divided into which two kinds of waves? |
Primary Secondary |
|
Which waves do the most damage? |
Surface waves |
|
Where do surface waves travel? |
Travel near the surface of the earth. |
|
Which waves travel through solids but not liquids? |
Secondary waves |
|
Which waves travel through solids and liquids? |
Primary waves |
|
Which waves are the slowest? |
Surface waves (S and P waves much faster) |
|
What does a seismograph do? |
Records seismic waves |
|
Seismic waves travel at (the same/different) speeds. |
Seismic waves travel at different speeds. |
|
What is a seismogram? |
A record of seismic waves. |
|
What is the distance to the epicentre? |
Distance estimated by the change in time between different wave arrivals. |
|
Do P waves or S waves outrun the other through the interior? |
P waves outrun S waves |
|
What results in a greater discrepancy when calculating the distance to the epicentre? |
The farther the distance to the seismograph, the greater the discrepancy. |
|
What are some earthquake hazards? |
Ground shaking Mass wasting (liquifaction, landslides triggered by ground shaking) Tsunamis (location dependent)
|
|
What are the four historical earthquakes of the cordillera? (Location, M, Year) |
Queen Charlotte – M8.1, 1949 Vancouver Island – M7.3, 1946 Vancouver Island – M6.9, 1918 Cascadia Subduction Zone – M9.0, 1700 |
|
The Cascadia EQ generated what hazard? |
Generated a tsunami recorded in Japan. |
|
What are the average reassurance intervals for the Cascadia EQs? |
400-600 yrs |
|
What is the current research in Cascadia EQs focused on? |
Current research – looking for early warning signs (Episodic Tremor and Slip). |
|
What evidence is there of Cascadia EQs? |
Drowned marsh deposits: Cascadia deep sea sediment core showing great earthquake induced sedimentation events |
|
Mt. Mazama ash (crater lake) was deposited how long ago? |
7770 years ago |
|
What is the cause of cascade EQs? |
Subduction Zone Crustal Uplift |
|
What are the four factors in planning for earthquakes? |
Building to withstand ground shaking Modeling and planning tsunami evacuation routes Earthquake forecasting & monitoring Education |
|
What does ETS stand for? |
Episodic Tremor and Slip |
|
What is Episodic Tremor and Slip? |
Episodic tremor and slip is a new phenomenon discovered in the Cascadia subduction zone. Consists of repeated slow slip events on the lower portion of the subduction fault, accompanied by unique non-earthquake tremor-like seismic signals that emanate from the same region. |
|
In an earthquake with a duration of 20 to 60 seconds and violent ground shaking intensity, what would the damage look like? |
Skyscraper built to code |