A glacier is basically an accumulation of snow. There are only two places they form; one is the North Pole, the other at the South Pole. Over time this snow builds on itself and then compacts down the old snow due to the weight of the new snow creating ice and a glacier over time. The compression of the glacier continues for dozens, hundreds or even thousands of years, adding more and more layers on top and adding even more weight. The ice eventually gets compressed so much that most of the air is forced out of it. This is what causes glacial ice to appear blue. Later the glacier becomes so heavy that it starts to move. There are basically two forms of glacier movement; spreading, and basal slip, and most movement is said to be a mix of both. Spreading occurs when the glaciers own weight becomes too much for it to support itself. The glacier will gradually expand and spread out. Basal slip occurs when the glacier rests on a slope. Pressure causes a small amount of ice at the bottom of the glacier to melt, creating a thin layer of water. This reduces friction enough that the glacier can slide down the slope. Loose soil underneath a glacier can also cause basal slip.
What is some evidence of Pleistocene glaciations in USA (WHERE?). Include terms; gravity, shear stress, ground and terminal moraine, loess in your explanation.
California is one of the places in USA where there is evidence of Pleistocene glaciations. Sierra Nevada mountain has about 800 little mountain glaciers as well as perennial ice fields. In this mountain there is a palisade glacier located in the right of the Sierra crest with several moraines such as moraine-dammed lake displayed in dark blue and the brown moraines which are found at the glaciers edge due to glacial movement.
SEA LEVEL: What is relative sea level (RSL)?
The relative sea level is the position and height of sea relative to the land or sea level related to the level of continental crest and it is used to measure the movement of land versus the movement of water.
What is Eustatic sea level? How is sea level measured?
Eustatic sea-level is the level of the ocean surface when it is halfway between the mean high and the low tide and is used as a standard to suppose the land altitude. Tide gauge is used to measure the seal level whereby the heights of the falling and rising tides are recorded for duration of time and it is used to calculate the mean sea level.
What are two (2) issues associated with using this (that) method to ascertain changes in sea level over time?
Climate change and sea level rise are the two main issues associated with using the tide gage in measuring the changes in sea level over a period of time.
What are three (3) potential problems associated with rising sea level (transgressive environment) along a coast?
The three potential problems are the drainage problems, destruction of infrastructures especially in low-lying areas thus affecting the coastal community and landslides and erosion which damages property.
What is transgressive environment?
This is when the water depths increases and continues to rise and it can cause pelagic fossils to be found on top of the water. In a transgressive environment the sediment grain size continue to decrease as a person moves high and high.
This is the opposite of the regressive environment for the water depths do not rise but get shallower increasing the grain size as well as the energy and the fossils are found at the bottom.
The coast of Maryland is transgressive or regressive? Why?
It is not able to specifically tell if Maryland is transgressive or regressive since it has undergone several transgressive and regressive phases.
- MINERAL RESOURCES: Name 2 energy (mineral) resources and 3 non-energy mineral resources
Energy mineral resources.
- Natural gas
Non-energy mineral resources
The difference between a RESERVE and a RESOURCE is?
Difference between the reserve and the resource occurs on the feasibility study. A resource is measured, indicated and inferred while as a reserve is proven and probable.
- Can one change into another?
In some circumstances a reserve can change to reserve.
- What are the major mineral exploration methods (general categories).
- Geochemical method
- Target generation and resource evaluation
- Remote sensing
- What is and where is the location of the Marcelleous Shale?
Marcelleous shale is a gas formation and is very rich in gas resources (natural gas wells and is located in Pennsylvania specifically positioned over the large Marcellus shale play.
- What is fracking?
Fracking is the process that is used to extract gas from shale rock layers that are found at the far deep of the earth.
- What energy resource associated with this shale?
Gas is the energy resource associated with shale.
HYDROLOGY: Define the following terms;
- Ground water is the water that seeps through the soil or rocks underground and it is a source of drinking water.
- Hydraulic head is the measure of the potential energy or a measure of liquid force above the geodetic datum.
19. Water table can be defined as the depth at which the underground water was first noticed and this depth is measured from the surface of the earth. Therefore, it is the height beneath which the ground is flooded with water.
20. Aquifer is the body of saturated rock that can allow water to pass easily.
21. Aquaclude is the body of rocks which hinders the flow of the underground water
Does groundwater move slow or fast –compared to average stream water flow?
The groundwater moves slow from the recharge areas to the discharge points compared to the stream water flow. This is because there are some factors that hinder the flow of the groundwater like the aquifer and the loose soil. Groundwater moves in parallel paths and it mixes with several things which cause the slow movement but the stream water follows a defined path to a particular discharge point.
- What is issue with contaminants in ground water?
Contaminants in the ground water are a problem to the human health since it makes human being to be exposed to many hazardous levels of contaminants depending on the level of contamination. This can also be the cause of diseases such as hepatitis and dysentery. It also reduces the amount of the usable water.
- Explain the term WATERSHED.
Watershed is the area of land with several sets of streams and rivers draining into the same large body of water.
- For example, the Chesapeake Bay Watershed—what does it mean and encompass?
Chesapeake Bay watershed encompasses six states namely Delaware, Maryland, New York, Pennsylvania, Virginia and West Virginia James River .The rivers that drain into it are the York River, Rappahannock River, Potomac River and the Susquehanna River. this means that the communities around it benefit and are also subjected to some of the problems that can come from it.
- COASTS: Define a beach.
A beach is a sandy show along the ocean which is between high and low water marks.
- What is the ‘shoreface’ along a beach?
This is along the coastline or the beaches and it is a narrow zone form the low tide beach it and it is always covered with water where the beach graves and sand move backward and forward as the wave changes.
- What is littoral drift (longshore sediment transport)?
Littoral drift is also known as the show drift and is defined as the process by which the sediments move by the side of the shoreline (transport of non-cohesive sediments).
- What is difference between ‘Groin” and Jetty”?
Groin is built across the beach and it is at a 90 degree angle to the shoreline in order to trap the sand. Jetty is built at the tidal inlets and is meant for stabilizing the locations of the inlets.
- Describe the general differences (shape & size) between the beaches of the west coast and the east coast for USA.
West coast beaches have larger waves than those in the east coast. The East coast beaches are bigger and uncongested and the ones in the West coast are smaller and congested. The beach shapes in west coast are well structured and interesting due to the larger waves experienced in the area while as the east coast beaches has unformed shapes which cannot be well explained.
Describe the difference in morphology between the beaches of Maine and Florida—sediment type, size, shape.
Maine beaches experiences a highest annual tide rise and with rocky shores, mud flats, and salt marshes and the beaches are sandy with bigger sediments full of variety of shapes. Florida beaches contains many shape of grains which are rounded edges, sharp edges, and crystalline among others.
- What is wave refraction and how does it relate to longshore current.
Wave refraction is the change in the direction of the wave that is caused by the change in its transmission medium. Wave refraction is related to the long shore current since the approaching and the refracting waves are the ones that cause the long shore current.
- What is a ‘rip current’?
Rip current is a powerful, narrow channel of fast-moving water from the beach via the surf zone.