Minerals
Rocks
Igneous Rocks
Sedimentary Rocks
Age Dating
100
What are the defining characteristics of a mineral (definition)?
Minerals are the building blocks of rocks (rocks (most rocks anyway) are composed of minerals. A mineral is natural occurring, inorganic, and crystalline.
100
What is a rock?
rocks (most rocks anyway) are composed of minerals.
100
Relationship between crystal size and cooling history (fast/slow cooling)
The size of the mineral crystals that form depends on how fast the magma cools and solidifies.
100
Sorting of sediments, how does it work/relate to energy?
The bigger the sediments are the more energy it requires to move them.
100
Types of age dating, other ways in which the earth was dated
Relative age – the ordering of objects or features from oldest to youngest. Absolute age – establishing the date of an event.
300
What affects these physical properties? How does composition/structure affect hardness, solubility, color, cleavage, etc?
Composition and structure affect the physical properties. Based on how they are composed, the rest changes.
400
Mohs Scale of Hardness
1. Talc 2.Gypsum 3.Calcite 4.Fluorite 5.Apatite 6.Orthoclase 7.Quartz 8. Topaz 9.Corundum 10.Diamond
400
4 Steps in formation of sedimentary rock (generation, transpo, depo, lithification)
Generation: Rocks on or near Earth’s surface are physically broken into smaller pieces, and mineral undergo chemical changes to form weaker minerals (weathering). Transportation: sediments are removed from its place of origin by running water, winds, or glaciers (erosion). Deposition: is the geological process in which sediments, soil and rocks are added to a landform or land mass. Lithification: The process of compaction and cementation that convert sediment into a sedimentary rock.
400
Unconformities (3-types)
- a gap in the rock record when erosion occurred rather than deposition. (1) Angular unconformity – tilted rocks are overlain by flat-lying rocks. (2) Disconformity – strata on either side of the unconformity are parallel. (3) Nonconformity – metamorphic or igneous rocks in contact with sedimentary strata (non-sedimentary=non-conformity).
500
What are the physical properties that distinguish mineral types?
Composition (What’s in it), and internal structure (“how it’s put together”). No single property distinguishes a mineral. Luster- How it reflects light (glassy, dull, metallic). Color. Streak – the color of a mineral scratched on unglazed porcelain. Hardness- resistance to scratching. Hard minerals scratch softer ones (calcite is softer than quartz). Cleavage – the way a mineral “breaks” into smaller bits of characteristic shape. Crystal Form- Characteristic shapes of crystal growth. Crystal Habit – how groups of crystals grow in association with one another. Optical Properties– thin sheets of minerals appear and behave differently under normal and polarized light.
500
Rock cycle, interactions among rock types?
The rock cycles recycle Earth materials. The rock cycle links together different materials and processes on Earth to form components of the three principal groups of rocks. An igneous rock can re-melt to form a new igneous rock, a sedimentary rock can re-erode and become another sedimentary rock, and a metamorphic rock can be heated and transformed over and over.
500
Types of igneous rocks (volcanic, plutonic, mafic/felsic)
Volcanic: form when magma in Earth’s interior rises to the surface through pipes or fractures in the crust. They cool rapidly at the surface. Plutonic: Cool below Earth’s surface. Mafic/Felsic: Magic is low silica, High iron (Fe), and magnesium, dark rock. Felsic is high silica, light colored rock.
500
Types of sedimentary rock (clastic, chemical, biochemical), how each is formed (processes)
Clastic: composed of sediments, they are formed from rock and mineral fragments. This process occurs in generation of clasts due to the breakdown of an original rock by weathering, (2) transportation of the eroded material from the source area. (3) Lithification, the deposition and subsequent conversion of the material of rock. Chemical: rocks form when minerals precipitate (crystallize out) from a solution as a result of changing physical conditions. Biochemical: result from the actions of living organisms that cause minerals to be extracted from a solution or are composed of the remains of dead organisms.
500
Principles of relative age dating
Principle of Superposition-rocks formed in layers, one above the other. Lowest rocks formed first and each higher layer is younger than the one below. Principle of Original Horizontality-sedimentary layers are horizontal when deposited. Angled layering indicates disruption following deposition. Principle of Cross-Cutting Relationships-geologic features, such as dikes and faults that cut across continuous rocks must form after the rocks they cut across. Principle of Inclusions-objects enclosed by rock must have formed prior to inclusion in the rock. Principle of Faunal Succession-states that certain fossil assemblages succeed each other in a specific order.
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