501 Soil Exam

geology defined as study of

earth as a whole, including origin, history (development of life), structure, composition and the nature of the process that hvae given rise to present state

What is the chief objective of geology?

to acheive an understanding of the CHANGES that take place in and on earth and to understand the REASONS for that change - dynamic forces that cause changge

Temperature of Earths core believed to be?

5500 C - same as sun

How is the earths internal heat engine controlled?

slow movement of magma deep within the earth towards the cooler surface

What heat transfer is believed to be responsible for most of the movement within Earths interior?

convection

What is convection?

upward movement of hotter, less dense materials and downward movement of higher dense, cooler materials

Are hotter materials more or less dense than cooler materials?

LESS

We’ve never gotten past what part of the Earth?

the crust

What are the three concentric zones in the earth?

core, mantle, crust (like an egg)

About how thick is the crust?

0-100km

Levels of the earth from outside to inside?

Lithosphere

Asthenosphere

Mesophere

Lithosphere includes?

1. Crust

2. upper most solid mantle

Mantle includes?

1. upper most solid mantle below crust

2. asthenosphere

3. mesophere

4. mantle

Ocean floor part of what level of earth?

1. crust (oceanic)

What is thicker? The continental crust or the oceanic crust?

continental (0-100km thick), earth ~ 0-5km

What two types make up the earths crust?

1. continential crust

2. oceanic crust

Oceanic crust is comprised of rock that is ____ in nature than that of the continents

denser

earths upper layer are composed of

silicate rock and minerals

two of the more populat silicate minerals?

Feldspar, quartz

Mantle is believe to be liquid or solid?

solid (minus a few spots)

The upper mantle underlying the lithosphere is called?

asthenosphere

how does the asthenosphere behave?

plastically and is ductile

What can be deformed like silly putty in response to the warmth of the Earth?

the asthenosphere

Core believed to be solid or liquid?

both - with a bit of iron

-outer core liquid

-inner core liquid

the metallic core protects us from?

radiation

what earth level is broken into?

plates

plates move relative to each other sliding on the underlying Asthenosphere

TRUE

the lithosphere moves as a result of?

underlying mantle convection

The flowing asthenosphere carries ____ on its back

the lithosphere, including continents

earthquakes have to do with?

internal temperature of the Earth along plate hot spots

Diverging boundaries are what?

spreading centres or locations where plates move apart

converging boundaries are?

locations where plates move towards each other

Where does a zone of subduction occur?

where continental plates meet oceanic plates

last 10,000 years is called?

the holocene

Currently living in what extinction?

6th

What’s the most recent geological period of time in Earths history?

the quaternary period

Two epochs of the quaternary period

the pleistocene “ice age”

the holocene (present warm interval)

The Quaternary period is characterized by a series of

large- scale environmental changes

A distinctive feature of the quaternary

(interglacial cycles) - build up of major continental ice sheets and mountain ice caps from long lasting glacial stages divided by warm episodes of shorter duration

Human induced climate change is true but its also part of a natural process, no way to know how much of each. We’re currently in a warm cycle

TRUE

how many glaciations in the last 800,000 years?

8-10

What was one of the largest Northen Hemisphere glaciations?

• the last one, the Wisconsin glaciation

18,000 - 20,000 years ago, the

Wisconsin glaciations reached its maximum

Holcene has been the last

10-12,000 years or the last hald of the wisconsin glaciation

When did the Holocene Epoch begin?

at the close of the paleolithic ice age

glacier definition

large, long lasting mass of ice formed on land that moves by gravity

Jasper is a good example of what glacier?

Valley glacier

Characteristics of a valley glacier?

• confined to a valley

• flows from HIGH to LOW elevation

• U-shape

U-shaped glacier

valley glacier

Cirque / Alpine glaciers

high in the mountains

Ice sheet

unconfined and covers large areas of land

Ice cap or Ice fields

similar to ice sheets but smaller

Tide water or Freshwater glaciers

What you picture when you think of a glacier

unsorted and unlayered rock debris carried or deposited by a glacier

Glacial till

What is till?

any unsorted material deposited by a glacier

glacial erratics

movement of rock by glacier to a spot where its different than the native rock in the area

A body of till is commonly reffered to as

a morraine

morraine refers to the

placement of till relative to the glacier

what is a laterial morraine

located along the edges of the glacier

what is a medial morraine

located within the body of the glacier IN THE DIRECTION of movement

Terminal morraine

located at the farthest point of the former glacier

the further point the glacier went in history

Ground morraines

thin, extensive layer of till that is formed as rock is dragged along by a glacier

Edmonton is situated within the

alberta plains

underlying the city is the

Edmonton formation, followed by Bearpaw Shale

Bedrock is how old?

Late Cretaceous and Early Tertiary in age ( at least 65 million years old)

Edmonton formation has been highly?

eroded by pre-glacial and glacial activity

There is a lot fo variability in the Edmonton formation

Edmonton formation consists of primarily?

fine-grained bentonitic sandstone and silstone interbedded with silty clay stone

Whats common in the area?

coal and bentonite beds

What time was the basic configuration of the bedrock surface set?

Preglacial time

What is placed on top of the canadian shield out west?

clay till

Dominant topographic features of the bedrock in the area are?

Beverly Valley and Stoney valley

The most common surficial deposit in Edmonton area?

sediment from Glacial Lake

Why are the exact limits of Glacial lake Edmonton approximated?

because teh sediments from the old shoreline were thin and have been altered by soil forming processes

Glacial Lacustrine deposits around Edmonton are generally characterized by

very silty clay

What type of morraine is common in the southeast area of the city?

ground morraine

Geologist definition of soil

layer of unconsolidated material located above the bedrock (mostly glacier till)

Difference in dirt and soil definition?

dirt is dead and cannot support life

3 components of soil?

• solid phase

• water phase

• air phase

What do you have in the solid phase of soil?

organic and inorganic

What is in the organic solid phase of soil?

any organisms dead or alive

What is in the inorganic solid soil phase?

mostly silt, sand and clay (small amount of gravel)

Soil percentage break down?

25% water

25% air

45% sand, silt, clay

5% plant debris

What is the 4th thing we can’t life without?

soil

Parent material of soil?

bedrock thats weathered in place or sediments and smaller materials carried by floods, glaciers or winds

soils are dynamic and change with time

TRUE

soil limited or unlimeted resource?

limited

Size of gravel?

grain size larger than 2mm

size of sand?

grain size between 0.05 and 2mm

size of silt?

grain size between 0.002 and 0.049mm

size of clay?

smaller than 0.002mm

Soil classification not consistent world wide

TRUE

What material is harder for water and contamination for flow through and why?

Clay because they lay flat and have a large surface area so become packed tightly

clay swelling is result of

increase in interlayer spacing in particles

loam definition

a soil with a mixture of particle types (silt, sand, clay, organic matter)

2 methods to classify soil grain size

1. sieve analyses

2. hydrometer

AB tier 1 requires what for soild grain size classification and for fine vs course classification?

sieve analyses

sieve analysis best used for what type of material?

course

Sieve analyses result?

gives a percentage based on weight - comparing total weight with weight of soil in each sieve

best method to use to differentiate between fine and course?

hydrometer - measure the densities in water