Lab 6

Question 1

What is groundwater

Answer 1

Groundwater is water found filling pore spaces beneath the earth’s surface in a zone called the zone of saturation

Question 2

what is the difference between the zone of saturation and unsaturated zone

Answer 2

the zone of saturation has all the pore space filled with water. The unsaturated Zone has some combination of water and air, or only air

Question 3

What can make up the zone of saturation

Answer 3

the zone of saturation may be loose soil and debris, or may be rock that has some pore space to it (that is open spaces)

Question 4

What is the porosity

Answer 4

the ratio of open spaces to solid material is called porosity, expressed as a percentage

Question 5

What is Permeability

Answer 5

If the pores are not connected, the water cannot move and so the material would be considered impermeable. The better the spaces connect, the more easily the water can move through the material, and this can be measured and is called permeability.

Question 6

What is an aquifer

Answer 6

an Aquifer is a body of rock or sediments that is capable of both storing (porosity) and transmitting (permeability) water

Question 7

What is an unconfined aquifer

Answer 7

an aquifer that has no confining layer between it and the land surface

Question 8

what is the water table

Answer 8

the top of the zone of saturation in an unconfined aquifer

Question 9

What is a confined aquifer

Answer 9

a confined aquifer is an aquifer that is blocked from the surface by an impermeable layer. Can develop higher pressures than is found in the groundwater above them.

Question 10

What is the potentiometric surface

Answer 10

The theoretical water table for an unconfined aquifer. The imaginary level the water would rise to if it could due to higher pressure in unconfined aquifers

Question 11

What is an artesian aquifer

Answer 11

A confined aquifer is sometimes called an artesian aquifer because if it contains enough pressure that a well drilled into it will send water above ground level, it creates an artesian well, a well that flows under its own pressure (no pumping required)

Question 12

What is a piezometer

Answer 12

a well drilled to simply determine the level of the groundwater, without pumping or injecting water.

Question 13

How can we draw the water table

Answer 13

By connecting water levels in piezometers and other known points of a water table (river, lake, non-pumping well)

Question 14

What is a potential gradient or hydraulic gradient

Answer 14

Often the water table is not flat, because water is being added to a system in one area and removed from another area. the inclined surface is called the potential gradient or hydraulic gradient. Can allow us to determine the direction of flow in a system

Question 15

What is a hydraulic head

Answer 15

Measuring the difference in elevation of the water table in different locations can give us the difference in water pressure between these locations which is called the hydraulic head. It is effectively how hard the water is being “pushed” by gravity from high areas to low areas.

Question 16

How can we determine the rate at which water in an aquifer should flow

Answer 16

By combining the hydraulic head with the conductivity of the aquifer (conductivity is largely based on permeability)

Question 17

What is a cone of depression

Answer 17

When we pump from a water well faster than the water can be replenished, the water. level in the surrounding aquifer drops more and more as you approach the well, causing what is called a cone of depression

Question 18

How do plant leaves and twigs become diamond

Answer 18

Energy derived from sunlight is used to fix carbon, nitrogen, and other nutrients to form organic matter (plants and twigs) by photosynthesis
Burial of plant and other organic matter in stagnant or low-oxygen aquatic environments forms peat
Continued compaction and heat of burial drive off most of the volatile elements and water, leaving a compact material (coal) that is high in carbon
Further metamorphisms recrystallizes the carbon into the mineral graphite
Extremely high pressures found only in the earth’s mantle change the carbon atoms again into an even more stable crystalline form, diamond

Question 19

What minerals might be added to a shale in order of metamorphic grade

Answer 19

Chlorite, Muscovite Mica, Biotite Mica, Garnet, Staurolite, Sillimanite.
Quartz and Feldspars are present throughout metamorphism