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

The main elements in the Continental Crust

Element	% by Weight
Oxygen, O	47
Silicon, Si	28
Aluminum, Al	8
Iron, Fe	6
Calcium, Ca	4
Sodium, Na	3
Magnesium, Mg	2
Potassium, K	2

• 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