Energy Geol
Norman Bowen in the early 1900's conducted experiments where he melted and cooled rocks and found that minerals common in the crust and mantle (blank)
crystallized at different temperatures
What is latent heat?
energy absorbed or released during a phase change. "hidden" energy
The flow of incoming solar radiation (energy) from the Sun and the loss of energy back to outer space is called Earth's (blank)
energy budget.
The (blank) is primarily based on the first appearance and last appearance (extinction) of living organisms. Layers of known relative position that can be dated using radiogenic isotopes provide absolute ages to the scale.
geologic timescale
What are the three agents of metamorphism?
heat, pressure, fluids
What are the three basic types of rocks?
igneous, sedimentary, metamorphic
What is the principle of lateral continuity?
layers are continuous until encountering an obstruction
What is the principle of original horizontality?
layers of sediment are generally deposited in a horizontal position
Plate tectonics, earthquakes, volcanoes, hot spots, and the Earth's magnetic field are all a consequence of the Earth trying to (blank) its internal heat.
lose
Harry Hess proposed that new ocean crust was formed at (blank) by magma flowing up from the mantle.
mid-ocean ridges
What are porphyritic textures?
occurs when magmas cool slowly within the Earth allowing time for early growth minerals to crystallize, but then cool rapidly by moving to the surface so they are encased in a fine-grained matrix. The large crystals are called phenocrysts.
What are three types of weathering?
physical, chemical, biological
Basaltic lava flowing underwater cools very quickly and forms (blank).
pillow lava
The flow of incoming solar radiation (energy) from the Sun and the loss of energy back to outer space is called (blank).
Earth's energy budget.
What is the troposphere?
0-12km altitude, where weather occurs, where we live, most airplanes. Contains 80% of the atmospheric mass and 99% of its water vapor.
What is the Stratosphere?
12 to 50km altitude, temperature stratified, contains the ozone layer. Cooler near base (-50C) and warmer at top (-15C) due to absorption of the UV radiation from the Sun by the ozone layer (o3)
What is the Mesosphere?
50-80km altitude, the coldest part of the atmosphere. Temperature decreases with altitude to below -100C at its top
What is the ozone layer?
A layer in the stratosphere around 20-25km in elevation with elevated concentrations of ozone (O3) Absorbs UVC and much of the UVB radiation.
What is a mineral?
A naturally occurring, inorganic, solid with a defined chemical composition and crystalline structure.
If the lava flow is faster and cools quickly the surface can break while the inside is still flowing for a crumbly or blocky texture called (blank).
A'a
When is it estimated that the planets formed around the sun?
About 4.5 billion years ago.
What is the thermosphere?
About 80km to 500km. UV radiation from the Sun causes ionization of molecules (charge particles) Temperature can reach up to 2,500C during the day
Relative or absolute age dating: Use of nuclear decay of radioactive isotopes to determine how old a geologic feature is in years before the present.
Absolute age dating.
When does a subduction zone metamorphism occur?
Alteration of a subduction slab. This is a low temperature but high pressure region, with fluids. The rocks here are called blueschist due to the blue mineral glaucophane.
What are hotspots?
Areas of rising magma (plumes) in the mantle that commonly lead to volcanism in the overriding plate. They appear nearly fixed in space relative to the center of the Earth so as the plate moves a chain of volcanoes is formed.
What are the four subsystems of the earth?
Atmosphere, Hydrosphere, Biosphere, and Geosphere
Large plutons that are commonly associated with the roots of mountain belts are called (blank)
Batholiths
(Blank) sedimentary rocks are composed of grains that were the hard parts of living organisms (shells).
Biochemical
What is it called when there is a collapsed depression in the central vent of a volcano due to emptying of the magma chamber?
Calderas
What causes the magnetic field of the earth?
Caused by convection and solidifying of Fe in the liquid outer core which creates a strong electric current that generates a magnetic field. Provides a shield which deflects the solar wind which would otherwise blow away the atmosphere.
(Blank) sedimentary rocks are composed of grains (clasts/sediments) weathered and eroded from other rocks that are lithified into a new rock.
Clastic
What is a polar cell?
Cold air at the poles descends and moves toward the equator.
What are the compositional layers of the geosphere?
Continental Crust Oceanic Crust Mantle core
The (blank) causes moving air to defect to the right in the northern hemisphere and to the left in the southern hemisphere.
Coriolis Effect
What is the Wilson Cycle?
Cyclic process of closure and opening of the oceans basins
What is seismic imaging used for?
Depth in water, ex: ocean depth.
(blank) are formed when magma rises through pre-existing weaknesses such as a cracks and cool into sheet-like intrusion that cross-cuts layers.
Dikes
(blank) describes the process of converting one form of energy, such as chemical potential in natural gas, into kinetic energy to turn an electromechanical generator which produces electric potential.
Electricity generation
How do we buy energy?
Electricity is sold by the kilowatt-hour (kWh). It is equal to using one kilowatt of power for one hour. 1kWh = 3,600 kilojoules (kJ)
What is Energy?
Energy is a property that must be transferred to an object to heat it or perform work on it. Measured in Joules (J)
What is tephra?
Erupted material from a volcano
What are the components of the atmosphere?
Exosphere, Thermosphere, Mesosphere, Stratosphere, Troposphere, Hydrosphere, Biosphere and Geosphere.
How are ingneous rocks formed?
Formed from cooling magma and lava. They lose heat during this process (exothermic reaction).
Where is all the energy coming from to drive plate tectonics?
Heat from the geosphere
What is the name of the current interglacial interval?
Holocene
What is the principle of cross-cutting relationships?
If a body or discontinuity cuts across a stratum, it must have formed after that stratum
How are metamorphic rocks formed?
Igneous and sedimentary rocks enter pressure/temperate conditions where minerals within them are unstable and recrystallize into new minerals.
What are Glassy rocks (texture)
Igneous texture- chilled so quickly it made it look like glass- ex. obsidian
What are Phaneritic rocks (texture)
Igneous texture- large crystals- slow cooling -intrusive
What are Aphanitic rocks (texture)
Igneous texture- small crystals- fast cooling - extrusive
What is the theory of the moon formation?
It is hypothesised that about 4.5 billin years ago a Mars-sized body (Theia) collided with the Earth. The debris formed into the Moon. The impact also caused the Earth to tilt 23deg on its rotational axis.
(blank) are narrow fast-moving masses of air near the top of the troposphere at the boundaries of circulation cells. Flow is from east to west.
Jet streams
What is Kinetic Energy?
Kinetic energy is work required to accelerate an object to a given velocity. The same work is done by the object when it is decelerated.
What are the mechanical layers of the geosphere?
Lithosphere Asthenosphere Meospshere Outercore Inner core
What is lava?
Magma that has reached the Earth's surface.
What are pegmatites?
Magmas cool very slowly to allow for the growth of very large crystals (over a cm)
How is energy transferred?
Mechanical waves transfer energy through a medium. Individual particles oscillate while the wave propagates. Mechanical leaves can be longitudinal, transverse, or surface.
What are some ways we buy energy?
Natural gas, jet fuel, coal, gasoline, propane, wood (biomass), fuel oil, electricity and others!
When does burial metamorphism occur?
Occurs as rocks are buried.
When does regional metamorphism occur?
Occurs were metamorphic temperatures and pressures are exerted over large areas. Commonly associated with mountain building in collisional zones.
What is covalent bonding?
Occurs when atoms share electrons to complete their outer shells.
What is ionic bonding?
Occurs when atoms that are oppositely charged are attracted to each other.
(blank) sedimentary "rocks" are accumulations of organic matter within or associated with sedimentary rocks. Source of fossil fuels.
Organic
When a basaltic lava flows slowly and easily it cools into a ropey appearance and the rock is called (blank).
Pahoehoe
What are transform faults?
Plates that are sliding past each other.
What is power?
Power is the rate at which work is done, or the amount of energy transferred during a unit of time. Unit is Watt (W) which is 1J per second.
What are the five ways minerals are formed?
Precipitation, aqueous solution, crystallization (from magma), biological precipitation (critters ), and recrystallization (pre-existing minerals)
Relative or absolute age dating: Ordering geologic features (rocks units, faults, folds) by age without knowing how long ago in years they were formed.
Relative and it provided the basis for production of the geologic timescale.
How do geologists tell time?
Relative dating and absolute age dating
What is magma?
Rock that has melted and is located below the surface of the Earth.
What is biogenic weathering?
Root growth or Burrowing (termites, ants, rodents, worms, and others).
What is some evidence of the continental drift?
Shape of coastlines Similar Fossils Glacial rocks (350 Ma) in southern hemisphere away from the poles Tropical plant fossils north of the Arctic Circle Geologic fit (mountain belts, etc)
What type of volcano has very broad, low-angles. Low viscosity basaltic (low in Si) magma so their eruptions are not that volatile. Lava can flow slowly for great distances during episodes of eruption. The Hawaiian Islands are these volcanoes.
Shield Volcanoes
Minerals are grouped based on their chemical composition and internal structure, what are the two groups?
Silicates - Minerals that are built around the Si-O tetrahedron. Most of the minerals in the crust and mantle. and Non-silicates: Carbonates Oxides, halides, and sulfides Sulfates Phosphates
(blank) form when magma intrudes between layers pushing them apart.
Sills
Outer Space provides a fundamental energy source for the rest of the Earth System in the form of what?
Solar radiation.
What is potential Energy?
Stored energy. Potential energy is the energy "stored" by an object.
(blank) is the process of relating or tracing layers out from one location to another. Relative ages can be generated using the techniques previously mentioned.
Stratigraphic correlation
What volcano has high viscosity silica-rich magmas that are felsic to intermediate in composition, so they have explosive eruptions. Composed of lava flows, tephra, and pyroclastic flows. Steep flanks. Mount St. Helens and Mount Rainier.
Stratovolcanoes
What is the geosphere?
The Geosphere is the solid portion of the Earth. It is composed of rocks (molten rocks are included). Gravity caused the formation of layers based in density (different compositions).
What is the Moho?
The Moho is the boundary between the crust and the mantle. It marks a sharp change in the velocity of seismic waves causing them to be reflected and refracted (bent).
What is the biosphere?
The biosphere includes all living things on Earth: Plants, animals, archeabacteria, Eubacteria, Fungi, Protists
What are the compositional layers of the geosphere?
The crust, mantle, and core.
What is latent heat of evaporation?
The energy needed for liquid molecules to escape the surface of the liquid to become a gas.
What is latent heat of condensation?
The energy released as a gas changes into liquid water.
What is latent heat of fusion?
The energy that is needed by a solid to break their bonds and turn to liquid.
What is the law of superposition?
The geologic principle that states that in horizontal layers of sedimentary rock, each layer is older than the layer above it and younger than the layer below it. The rocks on the top are younger than the rocks at the bottom.
What is the hydrosphere?
The hydrosphere consists of the oceans, surface waters, groundwater, and frozen water. Don't forget water vapor in the atmosphere.
This absorbed energy is then re-radiated in all directions creating a second source of heat is called what?
The natural greenhouse effect.
What is the nebular hypothesis?
The nebular hypothesis is the idea that a spinning cloud of dust made of mostly light elements, called a nebula, flattened into a protoplanetary disk, and became a solar system consisting of a star with orbiting planets
What is physical weathering?
The physical breakdown of bedrock into smaller pieces. Mechanisms include: pressure expansion, freeze wedging, thermal expansion, wetting and drying, and expansion of salt crystals.
What is dissolution?
The process of dissolving. The removal of atoms from a mineral by water.
What is erosion?
The process of eroding or being eroded by wind, water, or other natural agents. The removal and transport of weathered rock fragments as either solid particles or as dissolved solutes.
What is albedo?
The reflectivity of a surface. White surfaces like snow and ice have high albedo. Land and dark surfaces like plants have low albedo.
What is radiation?
The transfer of energy by electromagnetic waves.
What is convection?
The transfer of heat by the movement of a fluid. Occurs when the heated material moves.
How are sedimentary rocks formed?
They are composed of pieces of other rocks that have been broken down as well as chemical and biologic precipitates. As they are buried by more material they are compacted and cemented together by precipitation of minerals in the space between grains.
What it the term used that converts volume to heating capacity?
This is called therm - A conversion factor is determined each billing period to convert volume to heating capacity. It is a unit of energy equal to 100,00 BTU's.
What is conduction?
Transfer of energy from one place to another by contact. A diffuse process where energy is transferred by intermolecular collision.
How is heat (energy)transferred?
Transferred by conduction, convection, and radiation
What are seismic waves?
Vibrations that travel through Earth carrying the energy released during an earthquake. Have longitudinal, transverse and surface components.
What is a Hadley cell?
Warm air rises at the equator and cools adiabatically causing condensation, rain, and release of latent heat.
What are transverse waves?
Wave in which vibration is perpendicular to the direction of energy transfer. Can not travel through fluids because fluids have no shear strength.
What are longitudinal waves?
Waves that move in the same direction as the wave (parallel). EX: sound waves
What is weathering?
Weathering is the breaking down of rock into small pieces over a long period of time.
What is chemical weathering?
Weathering of minerals through the breaking of chemical bonds. Water and oxygen are the main agents.
When does contact metamorphism occur?
When magma moves into rock
What are divergent boundaries?
When plates move away from each other.
What is flux-induced melting?
When water is added to rocks it acts as a flux which reduces the melting temperature. The solidus curve is depressed. Occurs at subduction zones where water is added from the subducting slab.
The Earth is a (blank) that can be thought of as four distinct subsystems or (blank) that interact with each other.
dynamic system and spheres
The difference in solar radiation measured the top of the atmosphere and at sea level is due to what?
reflection by clouds and the Earth's surface and adsorption by the atmosphere
What is the exosphere?
the highest layer in the atmosphere
What is albedo?
the reflectivity of a surface
An (blank) is a surface across which there is missing time in the rock record. It could either be due to non-deposition or erosion.
unconformity
Pieces of country rock that are not melted by the magma are called (blank).
xenoliths
