Geology and Nonrenewable Minerals Chapter 12

What are the earth’s major geological processes and hazards? Section 12-1 What are the earth’s major geological processes and hazards?

The earth is a dynamic planet Geology - the science devoted to the study of dynamic processes occurring on the earth’s surface and in its interior.

Layers of the Earth

Major features of the earth’s crust and upper mantle

The earth’s crust is made up of a mosaic of huge rigid plates

The earth’s major tectonic plates

Divergent plate boundaries Convergent plate boundaries EURASIAN PLATE NORTH AMERICAN PLATE ANATOLIAN PLATE CHINA SUBPLATE JUAN DE FUCA PLATE CARIBBEAN PLATE PHILIPPINE PLATE ARABIAN PLATE AFRICAN PLATE INDIA PLATE PACIFIC PLATE PACIFIC PLATE COCOS PLATE SOUTH AMERICAN PLATE NAZCA PLATE AUSTRALIAN PLATE Active Figure 12.4 This map shows the earth’s major tectonic plates. See an animation based on this figure at www.cengagebrain.com. Question: Which plate are you riding on? SCOTIA PLATE ANTARCTIC PLATE Divergent plate boundaries Convergent plate boundaries Transform faults Fig. 12-4, p. 278

Test 3 Be able to explain tectonic theory Plate tectonics is a scientific theory that describes the large-scale motions of Earth's lithosphere.

Volcanoes A fissure - a central vent or a long crack Many volcanoes form along the boundaries of the earth’s tectonic plates when one plate slides under or moves away from another plate.

Volcanoes Lava - Magma that reaches earth’s surface. Volcanic activity can release large chunks of lava rock, glowing hot ash, liquid lava, and gases into the environment.

Internal pressure in a volcano can cause lava, ash, and gases to be ejected

How do Volcanoes affect the environment? Know the gases! Large, explosive volcanic eruptions inject water vapor (H2O), carbon dioxide (CO2), sulfur dioxide (SO2), hydrogen chloride (HCl), hydrogen fluoride (HF) and ash (pulverized rock and pumice) into the stratosphere to heights of 10-20 miles above the Earth's surface

Earthquakes An Earthquake is the result of a sudden release of energy in the Earth's crust that creates seismic waves. 

Earthquakes Stress in the earth’s mantle can cause rocks to suddenly shift or break and produce a transform fault, or fracture in the earth’s crust.

Earthquakes When a fault forms or when there is abrupt movement on an existing fault, energy that has accumulated over time is released in the form of vibrations, called seismic waves, causing an earthquake.

An earthquake has certain major features and effects Know!

Earthquakes are geological rock-and-roll events The severity of an earthquake is measured by the magnitude of its seismic waves.

Earthquakes The magnitude is a measure of shaking caused by the earthquake, as indicated by the size of the seismic waves when they reach a seismograph.

The Richer Scale Insignificant (less than 4.0 on the Richter scale). Minor (4.0–4.9). Damaging (5.0–5.9). Destructive (6.0–6.9). Major (7.0–7.9). Great (over 8.0).

Earthquakes on the ocean floor can cause huge waves called tsunamis A tsunami is a series of large waves generated when part of the ocean floor suddenly rises or drops.

How a tsunami forms

How are the earth’s rocks recycled? Section 12-2 How are the earth’s rocks recycled?

Minerals and Rocks Mineral -an element or inorganic compound that occurs naturally in the earth’s crust as a solid with a regular internal crystalline structure.

Minerals and Rocks A few minerals consist of a single element such as gold, silver, and diamond (carbon). Most of the more than 2,000 identified minerals occur as inorganic compounds formed by various combinations of elements, such as salt (sodium chloride or NaCl) and quartzite (silicon dioxide or SiO2).

What is rock? Rock - a solid combination of one or more minerals found in the earth’s crust.

Limestone Some kinds of rock, such as limestone, contain only one mineral while most consist of two or more minerals, such as granite—a mixture of mica, feldspar, and quartz crystals.

Granite mica, feldspar, and quartz

Know! Three broad classes: Sedimentary rock (e.g. sandstone, limestone). Igneous rock (e.g. granite). Metamorphic rock (e.g. slate, marble).

Sedimentary rock Sedimentary rock is made of sediments- dead plant and animal remains and tiny particles of rocks. These sediments are deposited in layers that accumulate over time.

Igneous Rock Igneous rock froms below or on the earth’s surface when magma wells up from the earth’s upper mantle and then cools and hardens. Examples include: granite, lava rock.

Igneous Rocks

Metamorphic Metamorphic rock forms when a preexisting rock is subjected to high temperatures, high pressures, chemically active fluids or a combination of these agents. These forces my transform a rock by reshaping its internal crystalline structure and its physical properties and appearance. Examples include slate (shale) and marble (limestone).

Know the differences in the three types of rock.

The Rock Cycle

The Rock Cycle – Know this picture for test 3!

Section 12-3 WHAT ARE MINERAL RESOURCES AND WHAT ARE THE ENVIRONMENTAL EFFECTS OF USING THEM?

Mineral resources Mineral resource - a concentration of naturally occurring material from the earth’s crust that can be extracted and processed into useful products and raw materials at an affordable cost. Examples are fossil fuels (such as coal), metallic minerals (such as aluminum and gold), and nonmetallic minerals (such as sand and limestone). Minerals are classified as nonrenewable resources.

Ore Ore - rock that contains a large enough concentration of a particular mineral—often a metal—to make it profitable for mining and processing. High-grade ore contains a large concentration of the desired mineral. Low-grade ore has a smaller concentration.

Aluminum Ore Aluminum (Al) is used for packaging and beverage cans and as a structural material in motor vehicles, aircraft, and buildings. Aluminum is found as an ore called Bauxite.

Ore Steel, an essential material used in buildings and motor vehicles, is a mixture (alloy) of iron (Fe) and other elements that are added to give it certain properties. Copper (Cu), a good conductor of electricity, is used for electrical and communications wiring. Gold (Au) is used in electrical equipment, tooth fillings, jewelry, coins, and some medical implants.

Some environmental impacts of mineral use Life cycle of a metal—mining, processing, and using it—takes enormous amounts of: energy and water and can disturb the land, erode soil, produce solid waste, pollute the air, water, and soil. Know!!

Each metal resource that we use has a life cycle

Harmful effects of extraction, processing, and use of nonrenewable mineral or energy resources Know!