GMOA Notes

These are notes that cover Geology, Meteorology, Oceanography, and Astronomy.

Introduction
Earth's four spheres

Hydrosphere - dynamic mass of liquid that is always on the move
 * Oceans - the most prominent feature of the hydrosphere
 * 71% of Earth's surface is covered by ocean which is 97% of Earth's water
 * Only 3% is fresh water - streams, lakes, glaciers and underground supplies
 * Water Cycle - constantly recycles water

Atmosphere
 * Provides us with the air we breath
 * Protects us from the sun's intense heat and radiation
 * Protects us from space

Biosphere
 * Includes all life on Earth
 * Interacts and influences the other 3 spheres

Lithosphere
 * Earth's rigid outer layer called the crust and the upper mantle called the asthenosphere
 * Solid earth consists of 4 layers:
 * core
 * inner, solid core
 * outer, liquid core
 * mantle
 * lithosphere
 * Divisions of Earth's surface
 * continents
 * ocean basins

Sciences

Sciences involved in better understanding the earth integrate chemistry, physics, and biology into the following sciences:

Meteorology - the study of:
 * the atmosphere
 * weather and climate

Geology - the study of the Earth, and is broken into
 * Physical geology
 * minerals
 * rocks
 * Earth processes - mountain building, earthquakes, volcanoes, etc.
 * Historical geology - Earth's origin and it's past
 * physical
 * biological

Oceanography - study of the Oceans
 * Composition and movement of seawater
 * Seafloor topography and sea life

Astronomy - the study of the universe
 * Earth is a tiny object in a vast universe
 * to understand Earth helps us to understand other planets and vice versa

Resources and Environmental Issues

Environment
 * Physical environment (abiotic)
 * water
 * air
 * soil
 * rock
 * Biological - living environment (biotic)

Resources
 * Important environmental concern
 * Include:
 * water
 * soil
 * minerals
 * energy
 * Two broad categories of resources
 * Renewable resources
 * can be replenished
 * Examples: plant (lumber) and wind energy
 * Nonrenewable Resources
 * Fixed quantities
 * Examples: fuels and metals

Environmental Problems
 * Local, regional, and global
 * Human-induced and accentuated
 * Urban air pollution
 * Acid rain
 * Ozone depletion
 * Global Warming
 * Natural Hazards
 * Earthquakes
 * Landslides
 * Floods
 * Huricanes
 * World population pressures - in 30 years population increased from 4 to 7 billion
 * US makes up 6% of that but uses 30% of the annual mineral and energy resources
 * Alternate energy sources needed

Scientific Inquiry

Scientific Inquiry - scientific knowledge is gained through the following systematic steps called the scientific method, (PI-HE-RAC)

Gather facts through observation then ask why?
 * Problem - state the problem
 * Information about the problem
 * Hypothesis (untested best guess as to why)
 * Experimentation
 * Record and Analyze results
 * Conclusion - accept or reject hypothesis

Goal of science is to discover patterns in nature and use knowledge to predict what will happen under certain circumstances
 * Theory - tested and confirmed
 * Law - no known deviations have ever been found

Minerals
A mineral is a naturally occurring crystalline solid with a definite but not fixed chemical composition and ordered atmomic arrangement.

Chemistry and Mineral Terms

Chemistry Terms:


 * Chemical Property - characteristics of a material, which depends upon how the material reacts with other materials


 * Periodic Table - list of all known elements


 * Element - matter made up of atoms that are essentially all the same and cannot be subdivided by ordinary chemical methods


 * Atom - smallest part of an element


 * Nucleus - central part of an atom made up of protons and neutrons


 * Protons - subatomic particles with a positive charge


 * Electrons - subatomic particles with a negative charge


 * Neutrons - subatomic particles with a charge of 0


 * Atomic number - the number of protons in an atom (above element symbol on periodic table)


 * Atomic mass - the number of protons plus the number of neutrons (below element symbol on periodic table)




 * Isotope - change in the number of neutrons in an atom. Example, and isotope of sodium may have 10 or 12 neutrons


 * Electron Configuration - how the electrons are arranged around the atom in energy levels
 * 1st energy level has 2 electrons
 * all other energy levels have 8 electrons




 * Ion - change in the number of electrons
 * Atoms are most stable with 8 electrons in the outer energy level
 * Will share, lose, or gain electrons to achieve this


 * Ionic bonding - transfer of electrons
 * example - Sodium and Chlorine


 * Lewis Electron Dot Structure - Short hand for showing "chemistry" activity in the outer level by showing the number of electrons in the outer energy level




 * Covalent bonding - sharing of electrons. VERY STRONG BOND
 * example - bond between Hydrogen and Oxygen


 * Metallic bonding - electrons do not belong to any particular nucleus, they float between nuclei
 * example - two metals touching for a long time can "weld" to each other by metallic bonding. You can increase the speed of this by adding heat.

Mineral Terms:


 * A mineral is a naturally occurring crystalline solid with a definite but not fixed chemical composition and ordered atomic arrangement
 * Size of the ion is important because ions that are within 10% of the same size may be substituted in many minerals. This is why minerals of the same type have different chemical compositions.
 * examples - Si,Al; Fe,Mg; Na, Ca


 * Mineral formation
 * Melting - Volcanic activity
 * Evaporation - Salt water: Halite, Gypsum
 * Biological activity - sulfur producing bacteria
 * Oxidized - comes into contact with oxygen: Limonite
 * Leached - as water moves through the soil it dissolves elements. A leech line forms due to mineral formation where the water stops: bauxite
 * Metamorphic processes - formed by heat and pressure. Examples: graphite, chlorite, diamonds. Alters chemical composition and structure, called recrystallization


 * Mineral Types
 * Native minerals - contain one element
 * examples - graphite, C; Copper, Cu; Sulfur, S
 * Sulfides and Sulfates - contain Sulfur and other elements
 * Silicates - contain silicon and other elements
 * Oxides - contain oxygen and other elements
 * Carbonates - contain CO and other elements
 * will effervesce in the presence of an acid
 * Phosphate - contains PO and other elements


 * Physical Property - is controlled by the chemical properties of a material...how its bonded can determine the hardness and the type of impurities that are present in its change in color


 * Color - reflected light; very poor indicator of the true color due to impurities


 * Streak - true color of the mineral found by powdering it. This is found by scratching the mineral across a streak plate.


 * Hardness - the resistance to scratching


 * Cleavage - the tendency for a mineral to break along flat smooth planes that reflect light
 * This is controlled by a weakness in structure, may break where bonds are longer or fewer
 * predictable pattern, not random
 * 1 perfect - stacks like sheets of paper, example: mica
 * 2 perfect - break in two directions and is very clear, example: calcite
 * 3 cubic - breaks into perfect cubes, example: halite
 * none - no repeating faces
 * conchoidal fracture - concentric circles are around breaks, irregular fracture pattern, example: quartz


 * Magnetism - minerals that contain iron and are polarized, example: magnetite


 * Taste - how they taste: bitter, sweet, salty


 * Luster - appearance
 * metallic - look like metal
 * nonmetallic - look earthy


 * Density = mass/volume


 * Specific gravity - how heavy something is in air compared to how heavy it is in water


 * Radioactivity - the breakdown of atoms in the nucleus

Mineral Key
This is not a full table of minerals.

Igneous Rocks and Volcanoes
Rock Cycle
 * the rocks of the crust are classified into 3 types according to their origin
 * Two of the three types are formed by processes deep in the earth's crust and tell us about conditions within the crust
 * There are:
 * Igneous rocks - solidify from a melt or magma. If it cools fast small crystals form, if it cools quickly large crystals form
 * Metamorphic rocks - pre-existing rocks that are changed by heat and pressure within the crust.
 * Sedimentary rocks - weathered rock fragments of older rocks deposited in layers near the earth's surface by wind, water, or glaciers then cemented together by various agents. Records conditions on the Earth's surface.
 * the interactions among the forces that produce these three rock types can be illustrated by the rock cycle.

The Rock Cycle

Igneous Rocks
 * formed by the crystallization of magma
 * magma is a natural, hot melt composed of a mutual solution of rock forming minerals (mainly silicates) and some volatiles (maybe steam), that are held in a solution by pressure. Magma probably originates near the bottom of the crust.
 * magma that reaches the surface before solidifying is called lava.
 * two types of igneous rock
 * extrusive - reach the surface, small crystals, are called volcanic rocks, and cooled on the surface
 * intrusive - doesn't reach the surface, large crystals, called Plutonic rock, cooled below the surface

Volcanism - Volcanic Activity
 * Volcanoes are important because they provide clues about the earth's inaccessible interior.
 * Studying magma, gases and rocks we can determine chemical conditions, temperatures, and pressures within the crust and mantle.
 * Two factors control the violence of volcanic eruptions:
 * The amount of gas in the lava or magma - the greater the amount of gas, the more violent the eruption.
 * Viscosity - the resistance to flow, this determines how easily the gas escapes.
 * Two factors influence viscosity:
 * Temperature
 * Silica Content
 * Gases - most of the gas released from a volcano is steam, which is water vapor. The other gases that are released are