Deck 12: Environmental Geology and Earth Resources

Question 1

The idea of tectonic plates shifting across the earth's surface is central to explanations of geologic processes. Why is this idea still called the "theory" of plate tectonic movement?

Answer 1

Weathering:
The process of conversion of the rocks into small particles is called the weathering.
It is mainly two types:
1. Mechanical weathering
2. Chemical weathering.
Mechanical weathering: In the mechanical weathering an only physical change occurs, no chemical changes.
Chemical weathering: In the chemical weathering chemical changes occur, for example oxidation hydrolysis etc.
These processes are very helpful in the recycling of rocks; as the recycling process is depend on the type of rocks, for that inter-conversation these processes are very useful.
The processes and the components of the rock cycle are dependents on the type of rock. The rock cycle contain mainly following steps: creation, destruction, and metamorphosis. There are main three major rocks:
1. Igneous rock: this rock is made by magna or lava. Magna extruded to the surface of the earth from volcanic vents, which cools quickly to converted igneous rock.
2. Metamorphic rocks: this rock is made from the melting, contorting, and re-crystallizing of the other rocks by tectonic forces, squeeze, fold, heat, and re-crystallization of solid rocks in the deep of the ground.
3. Sedimentary rocks: this rock is made from the loose grains of other rocks are consolidated by time and pressure. For example sandstone is a type of sedimentary rock is made by the layers of sand and mudstone consists of extremely hardened mud and clay.

Question 2

What is a mineral and a rock ? Why are pure metals not minerals?

Answer 2

A mineral:
An inorganic solid with a specific composition and a specific interior crystal structure which occurs in biologically, is called a mineral. A mineral has a separate constitution or distinct composition and crystal structure. for example solid water (ice) which has a separate constitution and crystal structure so ice is a mineral, while liquid water is not a mineral due to absent of a distinct composition and crystal structure.
A rock:
A rock is made by different minerals. When individual mineral crystal are mixed together and held firmly in a solid mass, a rock is formed. For example granite is a rock, which contains quartz mineral, feldspar mineral and mica mineral.
Pure metals are not minerals because minerals have a specific property of crystallization which is absent in metals. So metals like iron, aluminum, copper etc. are no longer crystalline and thus they are not minerals.

Question 3

Geologic data from fossils and sediments provided important evidence for past climate change. What sorts of evidence in the rocks and landscape around you suggest that the place where you live once looked much different than it does today?

Answer 3

The Mesozoic period begins and ends with appearance and disappearance of dinosaurs, similarly in the Precambrian period single celled fossils, in the Paleozoic period reptile's fossils, and in the Cenozoic period mammals and humans fossils.

Question 4

Which countries are the single greatest producers of our major metals?

Question 5

We all use metals and fossil fuels obtained by mining. What responsibility does each of us have for the methods that produce the goods and services we enjoy?

Question 6

Describe some of the mining, processing, and drilling methods that can degrade water or air quality.

Question 7

Compare the different mining methods of underground, open-pit, strip, and placer mining, as well as mountaintop removal.

Question 8

Understanding and solving the environmental problems of mining are basically geologic problems, but geologists need information from a variety of environmental and scientific fields. What are some of the other sciences (or disciplines) that could contribute to solving mine contamination problems?

Question 9

What resources, aside from minerals themselves, can be saved by recycling?

Question 10

Exploring Recent Earthquakes
The USGS Earthquake Center is a site that gives you access to global earthquake monitoring data. Understanding the distribution of earthquakes will help you understand the patterns of earth movement, volcanoes, and mountain building processes. Earthquakes are also one of our most important geologic hazards worldwide. Go to Connect to find data and questions that let you examine real-time earthquake records and to demonstrate your understanding of this geologic phenomenon.

Figure 1 Probability of earthquakes in the coming half-century.

Question 11

Describe the most deadly risks of volcanoes.

Question 12

How does tectonic plate movement create ocean basins, mid-ocean ridges, and volcanoes?

Question 13

What is mass wasting ? Give three examples and explain why they are a problem.

Question 14

Geologists are responsible for identifying and mapping mineral resources, but mineral resources are buried below the soil and covered with vegetation. How do you suppose geologists in the field find clues about the distribution of rock types?

Question 15

Why is building on barrier islands risky?

Question 16

What is the "ring of fire"?

Question 17

What is a floodplain ? Why is building on floodplains controversial?

Question 18

If you had an igneous rock with very fine crystals and another with very large crystals, which would you expect to have formed deep in the ground, and why?

Question 19

Describe the processes of chemical weathering and mechanical weathering. How do these processes contribute to the recycling of rocks?

Question 20

Describe the processes and components of the rock cycle.

Question 21

The Mesozoic period begins and ends with the appearance and disappearance of dinosaurs. What fossils mark the other geologic eras?

Question 22

Heat and pressure tend to help concentrate metal ores. Explain why such ores might often occur in mountains such as the Andes in South America.

Question 23

What is the difference between metals and nonmetal mineral resources?