Earth Science Second Summative

mining

the process of mineral extraction from a rock seam or ore

ore

a natural

rock or sediment containing one or more valuable mineral

Modern mining technology

uses geophysical techniques that involve measuring the magnetic, gravity and sonic

responses of rocks above and around a prospective mineral ore body

geo physical techniques

measuring the magnetic, gravity, and sonic responses

surface mining

is used to extract ore minerals near the surface of the earth.

The soil and rocks that covered the ores are removed through blasting

blasting

is a controlled use of explosives and gas exposure to break rocks

Strip Mining, Open pit mining and dredging

Three kinds of surface mining

Strip Mining

This mining type involves the removal of a thin strip of

overburden (earth or soil) above a desired deposit, dumping the removed

overburden behind the deposit, extracting the desired deposit, creating a

second, parallel strip in the same manner and depositing the waste materials

from that second (new) strip onto the first strip

Open-pit Mining

This is the most common type of surface mining. Open pit

means a big hole (or pit) in the ground.

open pit mining

It is used to mine gravel and sand and even rock

strip mining

This mining method is used

for coal, phosphates, clays, and tar mining

Dredging

This is the process of mining materials from the bottom of a body

of water, including rivers, lakes, and oceans.

Underground mining

is used to extract the rocks, minerals and other precious

stories that can be found beneath the earth's surface

Mineral processing

the process of extracting minerals from the ore, refining

them, and preparing these minerals for use

Sampling, Analysis, Comminution, Concentration, Dewatering

Five steps to mineral processing

Sampling

is the removal of a portion which represents a whole needed for

the analysis of this material

Analysis

is important to evaluate the valuable component in an ore. This

includes chemical, mineral and particle size analysis

Comminution

is the process where the valuable components of the ore are

separated through crushing and grinding

Dewatering

uses the concentration to convert it to usable minerals. This

involves filtration and sedimentation of the suspension and drying of the solid

materials harvested from this suspension

Concentration

involves the separation of the valuable minerals from the

raw material

Fossil Fuels

are basically remains of plants and animals that died millions of

years ago

Coal

is an important and primary fossil fuel

present on Earth

Coal

are found

predominantly where forest trees, plants and marshes

existed before being buried and compressed millions

of years ago

Anthracite, Bituminous Coal, Subbituminous Coal, Lignite

Four major ranks of coal

Anthracite

It is a hard, brittle, and black

lustrous coal, often referred to as hard coal,

containing a high percentage of fixed carbon and a low

percentage of volatile matter

Bituminous coal

It usually has a high heating value and is the most common type

of coal used in electricity generation. It appears shiny and smooth at first glance, but

when you look closely, you will see that it has layers.

Subbituminous Coal

which is black in color and dull, and has a higher heating value than lignite

Lignite

soft brown coal; lowest grade

coal with the least concentration of carbon

Oil

is an organic

material, mostly algae, which was buried in mud at the

bottom of the sea and lakes. It is used mainly to produce

transportation fuels and petroleum-based products

Natural Gas

is a naturally occurring hydrocarbon gas

with the mixture of methane. It is the Earth's cleanest

fossil fuel and is odorless and colorless in its natural

state

natural gas

produced from sedimentary rock

formation by forcing chemicals, water, and sand down

a well under high pressure

exogenic processes

Processes that take

place at or near the earth's surface that

makes surface wear away.

weathering

Process of disintegration

(physical/mechanical) and decomposition

(chemical) of rocks

erosion

Transportation of material or rocks

from one place to another. Caused by

natural forces, vegetation, and human

activities.

deposition

Process where sediment

moved by erosion is dropped and comes

to rest. Process which sediments settle out

of transporting medium.

endogenic processes

Geological processes

that occur beneath the surface of the

Earth. Internal processes resulting in

reshaping of earth landforms

Moving of tectonic plates

Major Endogenic process

Heat

Type of energy related to the kinetic

energy of an atom

Primordial heat

heat remaining from collisions during Earth's formation

Tidal Theory

states that a huge tidal wave was raised on our Sun by a passing star. A long filament was drawn out a gaseous material, condensed and formed planets

radioactive decay

A spontaneous process in which unstable nuclei lose energy by emitting radiation

Primordial Heat and Radioactive Decay

Two sources of heat

geothermal energy

Energy derived from the heat in the interior of the earth

geothermal reservoir

deep areas of hot groundwater below the Earth's surface

Dry Steam, Flash Steam, Binary Cycle

Three types of Geothermal Powerplant

Dry steam power plant

underground hot water and steam are used to generate electricity

flash steam power plant

most common form of geothermal electricity generation, very hot water flows up through production wells in the ground under its own pressure, pressure decreases as it flows upwards, boils into steam, used to power a turbine generator, leftover water/steam injected back into the reservoir

binary cycle power plant

Uses lower temperature geothermal water to boil other liquids, which generate steam to turn turbines.

hydroelectric power

Electricity generated by flowing water

Dam

a barrier that runs across a river or stream to control the flow of water

Penstock

channels water from its natural environment (river, lake) to supply the dam reservoir

Powerhouse

houses the turbines driven by the waterfall and the generator driven by the turbines

Run-of-the-river

Channels a portion of a river through a canal or penstock; also called diversion

Impoundment

most common; uses a dam to store river water in a reservoir

pumped storage

water is pumped to a high reservoir and flows downward through a turbine ; pumps water uphill to a reservoir at a higher elevation from a second reservoir at a lower elevation