EARTH SCIENCE LECTURE/REVIEWER
SCIENTIFIC METHODS – step by step procedure in doing an experiment.
STEPS:
1. Ask a question.
2. Do background research.
3. Construct a hypothesis
4. Test your hypothesis by doing an experiment.
5. Analyze data and draw a conclusion.
6. Share your results.
THEORIES ON THE ORIGIN OF THE UNIVERSE
1. BOOK OF GENESIS – God created the universe in 6 days.
2. HINDU TEXT RIGVEDA – describes the universe as an oscillating universe in which a “cosmic egg” or
BRAHMANDA containing the whole universe expands out from a single concentrating point called
BINDU.
3. ANAXAGORAS - primordial universe.
4. LEUCIPPUS AND DEMOCRITUS – atomic universe
5. ARISTOTLE AND PTOLEMY – geocentric universe
6.NICOLAUS COPERNICUS – theory of heliocentrism
7. GIORDANO BRUNO – the solar system is not even the center of the universe
8. ISAAC NEWTON – the universe is static, steady-state and infinite.
9. RENE DESCARTES – Cartesian Vortex Model, the vacuum space is not empty at all but filled with
matter that swirled around in large and small vortices.
10. ALBERT EINSTEIN – static, dynamically stable either expanding or contracting
MODERN THEORIES ON THE ORIGIN OF THE UNIVERSE
1. BIGBANG THEORY - expanding and originated from tiny, infinitely dense point called singularity.
2. OSCILLATING – followed the general theory of relativity equations with positive curvature which
resulted in the expansion of the universe. Combination of big bang and big crunch.
3. STEADY STATE – universe is expanding but the density does not change.
4. INFLATIONARY – based on the big bang but expansion more rapid.
5. MULTIVERSE – one of the many bubbles in the universe.
ORIGIN OF THE SOLAR SYSTEM
1. Encounter Hypothesis
2. Nebular Hypothesis
3. Protoplanet Hypothesis
LIFE ON EARTH
1. LIQUID WATER – habitable zone not too hot and not to cold
2. HEAT SOURCE – internal and external heat source
3. ATMOSPHERE – protection. Vital for photosynthesis
EARTH’S SUBSYSTEM
1. GEOSPHERE
2. HYDROSPHERE
3. BIOSPHERE
4. ATMOSPHERE
MINERALS – is defined as a naturally occurring, inorganic solid with a definite chemical composition and
an ordered internal structure.
GENERAL CHARACTERISTICS OF MINERALS
1. Naturally occurring
2. Inorganic
3. Solid
4. Definite chemical composition
5. Ordered internal structure
MINERALOIDS – substances that fulfill all the requirements but do not have an ordered internal
structure.
COMPOSITION OF MINERALS:
1. Silicates – composed of silicon-oxygen tetrahedrons. They are the major rock forming minerals and
includes olivine and quartz
2. Oxides – consist of metal cations bonded to oxygen anions. Common oxides are magnetite and
hematite
3.Sulfides – consist of metal cation bonded to sulfide.
4. Sulfates – consist of metal cation bonded to the SO42- anionic group.
5. Halides – are composed of a halogen ion such as chlorine or fluorine.
6. Carbonates – are characterized by the presence of carbonic ion which bonds elements such as calcium
or magnesium to form calcite.
7. Native Metal – consist of a single metal such as copper and gold.
CRYSTAL STRUCTURE OF MINERALS
1. Cubic 4. Tetragonal
2. Orthohombic 5. Monoclinic
3. Triclinic 6. Hexagonal
PHYSICAL PROPERTIES
1. Crystal form and habit
2. Cleavage and Fracture
3. Luster
4. Color and Streak
5. Hardness
6. Density
ROCKS AND ROCK CYCLE
A rock is naturally-occurring, coherent aggregate of minerals such as natural glass or organic matter.
Weathering – is the process where rock is dissolved or broken down to smaller pieces
Erosion – when rocks and sediments are picked up and transported or moved to another by water, wind,
or even gravity
Lithification – process in which sediments compact under pressure and become solid rock
Metamorphism – alteration of the composition or structure of rock by heat and pressure
Formation of Igneous Rocks
1. below the surface from slowly cooling magma
2. On the surface from rapidly cooling magma
3. On the surface from the consolidation of particles erupted by volcanic activity
Formation of Sedimentary Rocks
1. From the cementation of sediments that have been deposited, buried or compacted over a long
period of time.
2. From the precipitation of minerals from ions in solution.
3. From the compaction and cementation of plant and or animal remains
Formation of Metamorphic Rocks
1. When the dominant altering factor is pressure
2. When the dominant altering factor is heat
CLASSIFICATION OF ROCKS
1. Igneous Rocks
a. crystalline
- intrusive rocks or plutonic rocks – slowly cooled magma
- extrusive or volcanic rocks – rapidly cooled magma
-porphyritic texture
b. pyroclastic
2. Sedimentary Rocks – are clastic when they form from lithification of rocks and mineral fragments.
3. Metamorphic rocks – maybe foliated when dominant agent of metamorphic is pressure or crystalline
when the dominant agent is heat.
ORES AND MINERALS
Ores – naturally occurring materials that can be profitably mined.
Deposit – considered a potential ore body if its located abundance is greater than its average abundance
or distribution on Earth ‘s crust.
Mineral can be an ore based from:
1. overall chemical composition
2. percentage of extractable resource with respect to its volume
3. market value of the resource
LOCATING ORES
1. hydrothermal fluid circulation
2. metamorphic processes
3. magmatic processes
4. kimberlite magma
5. chemical sedimentary processes
6. action of ocean waves or currents
7. chemical weathering
MINING ORES
1. prospecting or exploration
2. drilling
3. modeling
4. identifying and assessing
5. designing and constructing the mine
6. ore extraction
7. milling
8. mine site decommissioning
SCIENCE CONNECTION
In order to survive, the human body needs some minerals in specific amounts. These
minerals which are critical to health are called essential minerals. They are divided into major or
macrominerals (Na, Cl, K, P, Mg, S) and trace or microminerals (Fe, Zn, Se, Cu, Mn, Fl, Cr, Mb). The excess
or deficiency of these minerals is detrimental and could lead to sickness or death.
