Principles of Earth Science FINAL EXAM - Whitmore

Geology; Hydrology; Oceanography; meteorology; Astronomy

An Interdisciplinary Science:

- Earth Science includes a collection of related sciences:

> ______________: Study of the solid earth, including rocks, minerals, erosion, volcanoes, plate tectonics, the planets historical record, etc.

> ______________: Study of water, it's storage and movement as it passes though different parts of the hydrologic cycle (focus on people's use of water, pollution, and management)

> _________________: Study of Earth's oceans. Deals with the physics and chemistry of ocean water, its interactions with the atmosphere

> _________________: Study of Earth's atmosphere, weather, and climate (atmospheric science)

> _______________: Study of the heavens and their bodies, from planets to galaxies and the universe as a whole

Atmosphere; Hydrosphere; Geosphere; Biosphere

The Earth - 4 interactive Components:

- ________________: Air and other gases within the soil

- ________________: Soil moisture and rain

- ________________: Silt, clay, sand, underlying bedrock, and other materials

- ________________: Organic material and organisms

(Each interact with and influence each other) (they are all dependent on one another)

interactive; system; earth systems science

Earth Science: Systems and Synthesis:

- Earth's spheres are _________________ with each other

- A _____________ is a series of interactive components that form a complex and independent unit

- __________ _____________ ______________: An interdisciplinary approach to trace the systems and interactions of the planet

- Example: soils

Atmosphere; atmospheric pressure

_____________________: (Genesis 1:6-8)

- The gasses that surround Earth, held by gravity

- About 100 km (60 miles) thick

- Primarily nitrogen and oxygen

- Gasses are compressible, resulting in ________________ ____________

> varies in elevation

outer space

___________ __________: (Genesis 1:14-19)

- Outside of the earth's sphere

Hydrosphere

_________________: (Genesis 1:1-2) (1 Peter 3:5)

- All the water on Earth's surface

- 97% is held in the ocean

- Nearly all fresh water is in glaciers or groundwater

> Groundwater is the most important resource to humans

Geosphere

_________________: (Genesis 1:9-10)

- Solid, rocky components of Earth

- Divided into a number of units based on physical properties and composition

> Crust (continental and oceanic)

> Mantle

> Core (outer and inner)

Biosphere; euphotic zones

_________________: (Genesis 1)

- All living organisms on Earth

- Most productive regions are in tropical areas with abundant sunlight and high precipitation rates

> Oceans: the ______________ _________ (light penetrating areas) of continental shelves and coral reefs

> Land tropical rain forests

Bible Study

How do we do good __________ __________?

- Study original languages

- Compare one text with another

- Read commentaries

- Meditate

experimental; historical

The natural sciences can be divided into the ________________ sciences and the ________________ sciences

Experimental

_____________________ Sciences utilize controlled conditions in which a hypothesis is tested in a repeatable fashion

Historical

_____________________ Sciences investigate events in the past that cannot be repeated

- Multiple competing hypotheses

- Eyewitness testimony

Scientific methods; observations; questions; hypothesis; predictions; test; evaluate

The many disciplines of science share several characteristics and approaches, called ______________ ____________:

1.) A scientist begins their inquiry because of past or current ________________ of the world around them

2.) These observations usually prompt some _______________ for why something is the way that it is, or what might happen to it under certain conditions

3.) The scientist thinks of a _________________ (a possible explanation) that could answer the questions, or ________________ about what one should discover if a set of observations is true

4.) There should be a way to _________ that hypothesis/prediction against the existing observations and/or future observations

5.) The new observations will help to ______________ whether the hypothesis/prediction is successful; they can affirm or contradict the hypothesis/prediction

different domains; methods; rules; influence; unified

Brand's model of science/religion interactions:

- Science and religion operate in ___________ ______________

- Each use different ___________ and _________ (ie. scientific methods vs. scriptural interpretive rules)

- BUT both can ______________ each other through an interface where science and religion both make claims about the world

- The physical and spiritual world is ____________ , so science and faith have the same author and are not in conflict

Dominion Mandate; Biblical Stewardship; resource; renewable; non-renewable; resource estimate; reserve; proved reserve; no way

Dominion, Stewardship, and the Environment:

- Humans were given the task to rule over creation by God at the very beginning

- the _____________ ______________ is the theological term for this task

- ____________ ________________ was the plan from the beginning; it involves work and responsibility, even before the Curse

- Two important passages: Genesis 1:28 and Genesis 2:15

- A _______________ is any material that can be used by people

- Resources can be divided into Two categories:

> ______________: can be replenished over time

> _______-________________: exists in fixed quantities

- Resources can be described economically:

> A ____________ ____________ describes the highest possible amount of that material that may be available

> A ___________ is a resource that has been determined to exist or has a good likelihood of existing in the resource area

> A ___________ ____________ is a reserve that is known to exist and can be recovered economically

- There is ______ __________ to use resources without affecting the environment

- Because of the Curse, people perform the Dominion Mandate poorly (ie. Cuyahoga River fires of the 1900s)

- But with a proper understanding of our role as stewards and knowledge of Earth's systems, better decisions can be made (ie. Boxley Corps stream migration project)

Biblical

______________ ( Young Earth ) view of creation

- Assumes Bible is historically accurate

- Dates based on genealogies

- 6 - 10,000 years old

- Literal 24-hour day during Creation Week

- Worldwide flood

- Ice Age

- Tower of Babel

Naturalistic; old life; middle life; new life

Conventional ( ________________ )

- Big Bang about 13 billion years ago

- Solar system and earth about 4.6 billion years ago

- Simple life originated on Earth about 4.0 billion years ago; complex evolution begins in Cambrian

- Cambrian explosion about 530 million years ago

- Paleozoic "_______ ________" (542 - 245 million years)

- Mesozoic "___________ ________" (244 - 66 million years)

- Cenozoic "_______ ________" (66 - 0 million years)

Young-Earth; Old-Earth; Theistic; Naturalistic

Four main views of creation:

- __________-_________ creation

- _______-_________ creation

- _____________ evolution

- ________________ evolution

Young-Earth

__________-__________ creation beliefs:

1.) All of God's work of creation was accomplished in a six rotational-day period of time only a few thousand years ago

2.) God directly and miraculously created "kinds" of organisms that have since diversified in a limited fashion

3.) Humans were created separately and miraculously apart from other animals to be rulers over creation

4.) A global flood destroyed the world and its inhabitants at the time of Noah, and is responsible of the majority of sedimentary rocks and fossils found on the planet's surface

*** the oldest and most robust view among the Church

- remains the most rigorous and self-consistent view of the biblical texts

old-earth

_______-___________ creation beliefs:

- Numerous views, including Gap Theory, Day-Age, and progressive creation

- All posit creation by God over many million/billions of years

- Typically no evolution of man from non-human animals

- Noah's flood is local

Theistic

___________ Evolution beliefs:

- Also called "evolutionary creation"

- God uses evolution as means of creation

- All of life is genetically connected, including the evolution of man from non-human animals

- Noah's flood is local or a non-historical myth

Naturalistic

_________________ Evolution beliefs:

- Non-theistic view, with no discernible role for God (if He exists)

- All of life is genetically connected, including the evolution of man from non-human animals

- Genetic continuity between man and non-human animals

- Dominant view among scientists today

Naturalist

How does a ______________ look at the rock record?

- Uniformitarianism (the present is the key to the past)

- Chance, random processes control everything

- slow and gradual plate tectonics

- Evolution of life forms over long periods of time, things get more complex over time

- only limited catastrophic events (meteor impacts, volcanic eruptions, etc.)

- God does not exist, or if he does is not involved in the process

naturalism

Predictions of _______________:

- Transitional Forms (evolutionary trees)

- Beneficial Mutations

- Things are getting better (evolutionary improvement)

- Evolution of new body plans with myriads of new species

Creation

The Days of _______________:

1.) Space, matter, time, light (earth covered with water)

2.) Expanse between the waters

3.) continents, plants

4.) sun, moon, stars

5.) water animals, birds

6.) land animals, man

7.) rest

Creationist

How does a ______________ look at the rock record?

- Catastrophism

- God designed all life forms and created the earth to support them

- Catastrophic plate tectonics during the flood

- evolution of life forms over short periods of time, things lose genetic information over time

- should be transitional life forms, especially in post-flood times

Interventionism

Predictions of _______________:

- separate, distinct kinds followed by diversification

- evidence for intelligent design

- extinction of body plans, with no new body plans arising

Naturalism; Interventionism

Where does the evidence point?

- Favoring _______________:

> Sequence of vertebrate fossils

> Sorting in the fossil record

> Fossil reefs

> Time required to cool Igneous bodies

> Radioactive dating

- Favoring __________________:

> Information contained in DNA

> Lack of fossil Intermediates

> Problem of the origin of new body species

> Evidence that suggests a young earth

Natural sciences

evaluates data and discoveries from the natural world

social sciences

focus on people (ie. history and psychology)

engineering

_________________ and _________________: areas of science that focus on the application of science to material inventions

eyewitness testimony

_________________ _______________: Narrows possible explanations by providing information from someone who observed the event

crust; oceanic; continental

The ___________: the outermost "skin" of the planet (makes up less than 1% of the earth's volume)

- ___________ crust: Made of igneous rocks basalt and gabbro (covers about 60% of the earth's surface)

- ________________ crust: Made of igneous rocks granite and diorite and covered by sedimentary rocks (covers about 40% of the earth's surface)

Mantle

The ___________:

- 84% of the planet's volume

- 67% of the planet's mass

- Largest single component of the earth

- Upper ___________:

> Extends from bottom of crust to about 670km deep

> Made mostly of peridotite

Lithosphere

Combined crust and upper mantle

- composed of plates (many large and small slabs) that move with respect to each other

Asthenosphere

Below lithosphere. Higher temperatures allow rocks to flow in a more plastic way

lower mantle

The __________ ____________: higher density, temperature, and strength. More rigid than the upper mantle

core

The __________:

- from depth of nearly 2,900km to the center of the earth

- composed mostly of iron and nickle

- makes up about 15% of planet's total volume, but 30% of its mass

- Outer _________: liquid; iron/nickle alloy flows like water but extremely dense (largely responsible for earth's magnetic field)

- Inner __________: solid; extends from outer core boundary to the center of the earth

euphotic zone

_____________ ________: portion of the ocean where there is enough sunlight to permit photosynthesis

- Phytoplankton (microscopic marine photosynthetic organisms) form the base of this zone's food web

Aphotic zone

_____________ ________: deeper region of the ocean where sunlight never penetrates

system

a series of interactive components working together to form a complex and interdependent unit

hydrologic cycle

________________ __________: the set of processes that move water around the earth

- major source of energy is the sun

Mineral

What is a ______________?

- Naturally Occurring

- Inorganic

- Crystalline Solid

- Definite Chemical Composition

- Characteristic Physical Properties

Earth's crust

The most common elements in the _____________ _____________:

- Oxygen

- Silicon

- Aluminum

- Iron

- Calcium

- Sodium

- Magnesium

- Potassium

- Titanium

- Hydrogen

Silicates

The Main Mineral Groups:

1.) The ______________

- 1/3 of all known minerals (over 4,000) are silicates

- 95% of the earth's crust is composed of silicates

- Examples: Quartz, feldspar, olivine, hornblende, mica

Olivine; Pyroxene; hornblende; Biotite; Quartz

Structures of silicates (summary)

- ____________ (single tetrahedron)

- ______________ (single chain of tetrahedrons)

- ________________ (double chain)

- ____________ (sheet of tetrahedrons)

- ____________ (3 dimensional framework)

Carbonates; HCl

The Main Mineral Groups:

2.) The ________________

- (CO3)-2 is the common ingredient (the carbonate ion)

- Calcite CaCO3 (the main ingredient of limestone)

- Dolomite CaMg(CO3)2

- Carbonates, such as Calcite, will react when ______ is applied to them

Oxides

The Main Mineral Groups:

3.) The _____________

- O-2 is the common ingredient

- Hematite Fe2O3

- Magnetite Fe3O4

Sulfides; Sulfates

The Main Mineral Groups:

4.) ______________ and ____________

- S-2 is the common ingredient of the sulfides

- PbS (galena)

- (SO4)-2 is the common ingredient of the sulfates

- CaSO4H2O (gypsum)

Halides

The Main Mineral Groups:

5.) ______________

- One of the halide elements from column VIIB of the periodic table is the common ingredient (F, Cl, Br, I)

- NaCl (halite, table salt)

- CaF2 (fluorite)

Native

The Main Mineral Groups:

5.) ____________ Elements

- Elements that exist naturally on their own, without combination to other elements

- Sulfur

- Copper

- Gold

- Silver

- Diamond

- Graphite

Weathering; sediment; Lithification

_________________:

- All types of rocks can be weathered

- The process of weathering breaks rocks down into small pieces

- Weathered pieces of rocks are called "______________"

- Sediment can be lithified to produce sedimentary rock

- _______________ involves the following:

- Compaction

- Dewatering

- Cementation

Sedimentary

__________________ Rocks:

- Clastic (or detrital)

- Sandstone, mudstone, conglomerate

- Organic

- Coal, some types of limestone

- Chemical

- Rock salt, some types of limestone

Metamorphism

_______________________:

- Crystalline rock (interlocking crystals)

- Change by heat and/or pressure

- Melting does not occur

- New minerals grow during the process of metamorphism

Metamorphic

______________________ Rocks:

- Regional

- Heat and pressure

- Slate, schist, gneiss

- Contact (or thermal)

- Heat

- Marble

- Dynamic

- Pressure (sheering)

- Mylonite

Crystallization

_____________________:

- Crystalline rock (interlocking crystals)

- Crystals of various minerals form at different temperatures

- Bowen's reaction series

Igneous

______________ Rocks:

- Intrusive

- Formed underground from cooling of magma

- granite

- Extrusive

- Formed aboveground by cooling of lava

- basalt

- Creation Week (various deeply buried igneous and metamorphic rocks)

- Primarily formed on Day 3

- Crystalline basement rocks

- We tell them apart from other igneous and metamorphic rocks by their context

Lava; magma

Igneous Rocks:

- Crystalline (interlocking crystals)

- Cool from lava or magma

- _________: liquid rock above ground (Extrusive igneous rocks)

- ___________: Liquid rock below ground (Intrusive Igneous rocks)

- When identifying ask two questions:

- What is the texture?

- What minerals (or color, light colored or dark colored) is present? (Mineral size)

Bowen's Reaction Series

___________ ______________ ___________:

- N. L. Bowen, 1928

- Studied the order of crystallization of liquid rocks

- He discovered that minerals in igneous do not all form at the same temperature, but some form at high temperatures and others at lower temperatures

Useful

____________ Igneous rocks:

- Granite

- kimberlite pipes

- Gold/copper/metal mining

- gemstones

plutons

How long does it take for large _____________ to cool?

- Issue: some have claimed that it would take large plutons like batholiths or stocks tens of thousands or even millions of years to rise and then cool, making the young earth view impossible

- However, new data helps us understand how fast these plutons may have cooled, even as much as a few days

rapidly; crystallizes; convection; radiohalos

New findings:

- Granite magma has up to 24% water content by volume (called magmatic water)

- Plutons are now known to be injected ___________

- Magmatic water is released when the magma ________________ and helps carry heat away from the cooling pluton

- Cool meteoric water introduced by _________________ also help in the cooling process

- Fractures develop around the pluton as it cools, making conduits for more rapid water flow

- Evidence for how fast the cooling happens comes from _________________

Radioactive decay

___________________ __________:

- There are several different types of radioactive decay

- notice that in each case, the numbers of protons change (the atomic mass #), changing the name of the atom

half lives

________ _________ of Po isotopes:

- There are three Po radio nucleotides in the 238U decay series

- 210Po 3.1 minutes

- 214Po 164 microseconds

- 218Po 138 days

- Po radiohalos occur in granites

- Gentry has interpreted them as Creation Week rocks every time they occur

- U and Th radio halos also occur which imply at least 100 million years of radioactive decay has occurred since these radio halos formed

Zircons

- Tiny minerals often found embedded in biotite

- Zirconium silicate or ZrSiO4

- Uranium is about the same size as zirconium and easily replaces it in the crystal lattice, so zircons end up being rich in uranium and highly radioactive

- The alpha particles (He atoms) produced by the U decay is what scars the biotite and makes the radiohalo

diameter; bullseye

Radiohalos:

- The type of decay can be determined by measuring the _______________ of the _____________

low; vigorous; slowly; accelerated

Radiohalos:

- The half-life of 238U is about 4.5 Ga

- The half-life of 210Po is about 3 minutes

- Both the U and Po halos had to form at the same time, at temperatures < 150 degrees celsius

- this implies billions of years' worth of decay (the U) had to happen at ________ temperatures while the hydrothermal flow was still ______________ enough to transport Po away from the zircon crystal

- If the Po is transported too _________ , it will decay before it reaches the point source

- In other words similar times for the decay of U and Po, or _______________ decay at some point in the past

5-10; too slow

Radiohalos:

- The time window for the formation of Po halos appears to be between ___-____ days after the intrusion of the magma, or hydrothermal convection becomes ______ _______ for the Po to be transported

intruded; quickly cooled; Abundance

The Shap Granite:

- Intruded into fossiliferous Flood sediments (during Devonians). Shows that granites may have been ___________ and ___________ ___________ during the Flood year

- Silurian below

- Carboniferous above

- Metamorphic aureole around granite body

- ___________________ of U and Po radio halos found together which must have formed at temperatures < 150 degrees celsius

Rapid Metamorphism

__________ _____________________:

- In the metamorphosed Thunderhead sandstone it was found that at the staurolite isograd, the boundary between the gamet and staurolite zones, the mineral chlorite disappears from the rocks and muscovite decreases sharply, whereas staurolite appears and biotite becomes more abundant

- This can be explained by the mineral reaction:

- 54 muscovite + 31 chlorite --> 54 biotite + 24 staurolite + 152 quartz + 224 water which has been confirmed experimentally

- The generation of this water by this reaction at the prevailing high temperatures determined experimentally would this have resulted in relatively large volumes of hydrothermal fluids in the rocks surrounding this isograd. These would have been ideal conditions for the generation of Po radio halos in these metamorphosed sandstones, if Po radio halo formation does indeed occur as described by the hydrothermal fluid transport model

extremely rapid; metals; catastrophically; short

Radiohalos:

Implications

- The hydrothermal fluid transport had to be _______________ ________

- hydrothermal fluids are generated as the granitic magmas cool, so the timeframe for the cooling of these granitic magmas has to have been extremely short (only days) as the expelled hydrothermal fluids also carried away the heat

- Because hydrothermal fluids also transport other __________ in solution (such as gold, tin, copper, lead, zinc), these rapid flows of hydrothermal fluids had the potential to also rapidly deposit metallic ores, again within days

- preliminary reports of U, Th, and Po radio halos in regionally metamorphosed rocks could confirm that large-scale rapid flows of hydrothermal fluids ____________________ formed regional metamorphic complexes

- The results show that millions of years of radioactive decay has occurred in extremely __________ periods of time (days to weeks)

Sedimentary; Marine sedimentary

What are ___________________ rocks?

- Made of fragments

- Typically have layers and fossils

- Three types depending on composition of fragments

- Clastic (detrital)

- Chemical

- Organic

- ___________ __________________ rocks cover most of the earth's surface (flat layers are characteristic of rapid marine deposition, otherwise the layers would have great amounts of relief between them

lithification

Sedimentary rocks are hardened by the following processes:

- Compaction

- Dewatering

- Cementation

Cement

Sedimentary particles can be held together (cemented) by four different kinds of cement:

- Calcite

- Limonite

- Hematite

- Quartz

Clastic

___________ Sedimentary rocks:

- Shale (clay)

- Siltstone (silt)

- Sandstone (sand)

- Mudstone (mud)

- Conglomerate (if rounded clasts) Breccia (if angular clasts)

- Pebble

- cobble

- boulder

Chemical

The classification of sedimentary rocks: _____________

- In most cases, identify some type of mineral that is present and makes up most (or all) of the rock

- Limestone (calcite): CaCO3

- Dolomite (dolomite): (Ca, Mg) (CO3)

- Chert (quartz): SiO2

- Rock Salt (halite): NaCl

- Gypsum (gypsum): CaSO4 - H2O

Evaporation; precipitate

Evaportites and Precipitates:

- These are sedimentary rocks that have formed from some type of chemical process

- _______________ of a body of water can lead to the concentration and precipitation of various salts like halite or gypsum

- Some minerals will _________________ out of solution around deep sea vents and springs

- These rocks do not typically contain fossils, but usually have characteristic layering as found in most sedimentary rocks. They can be identified by various mineral and chemical tests

Organic

The classification of sedimentary rocks: _____________

- These have as their main component parts and pieces of once living organisms

- chert

- coal

- fossiliferous limestone

Limestone

- _______________ is hard to classify because often it has characteristics of all three groups of sedimentary rocks (clastic, chemical, and organic)

- Types:

- Tufa

- Oolitic

- Travertine

- crystalline

- Coquina

- Fossiliferous

structures

Sedimentary ________________:

- Sedimentary structures give us clues as to how fast and under what kinds of conditions and environments rocks were deposited

- Geologists look for these clues to help understand how the rocks were made and under what kinds of conditions

- Examples of what can be found:

- fossils

- bedding

- structure

- grain size

- fluid escape structures

- burrows

- clastic dikes

- rock type (like dolomite)

Important

________________ Sedimentary rocks:

- Coal

- Rocks containing hydrocarbons

- Halite, gypsum

- Limestone

- Sediments used for sand and gravel

- Rock that stores water

- Building stones (limestone, sandstone)

- Paleontology and earth history

Coconino

_______________ Sandstone:

- "Type" for many other cross-bedded sandstones

- well-known

- Commonly used to attack creationists because it is thought by most to be eolian (or fossil desert sand dunes)

- supposed example of win-blown desert dune deposit

- it's in the Grand Canyon

cross-bedding

__________-_____________:

- Sand dunes migrate whether they are in a desert or under water

- when they migrate, they make cross-beds

- Forms (in both air and water) when sand avalanches over the crest of a ripple or dune. Sand is carried up the slope by saltation (bouncing) and then avalanches over the crest. As this process repeats itself, the cross-bed grows and migrates. Often the angle in air is about 30 degrees and is called the angle of repose. In water the angle can also be this steep, but is often shallower.

aerial coverage

Cononino Sandstone: _________ ______________

- Arizona

- Colorado

- Idaho

- Kansas

- Montana

- Nebraska

- Nevada

- New Mexico

- North Dakota

- Oklahoma

- South Dakota

- Texas

- Utah

- Wyoming

old-earth

The Coconino Sandstone is a centerpiece for the ______-_________ argument:

- Mud cracks in Cononino

- Mud cracks below Coconino

- Rain drop prints

- Steep cross-beds

- Animal tracks

- Frosted sand grains

- Dolomite is not widespread

literature; analysis; results

Coconino Sandstone Research approach:

- Study the _______________ (library work)

- Study modern sand dunes (field work)

- Study the Coconino Sandstone (field work)

- Laboratory _____________ of collected samples (lab work)

- Presentation of ___________ of scientific meetings

- Creationist and conventional meetings

- Write scientific papers

- Both Creationist and conventionalist

look like

What is the Coconino Sandstone supposed to ________ _______?

- Well-sorted

- Well rounded

- Steep cross-bed dips (33 degrees)

- No mica or dolomite

- Mud cracks at base

- Vertebrate tracks in dry sand

- Rain drop prints

Myths

10 ________ related to the Coconino:

1.) Steep cross-bed dips (~34 degrees)

- Cross-bed dips in the Coconino are about 20 degrees

2.) Well rounded and well-sorted

- Coconino is neither rounded or well-sorted

3.) Mud cracks at the base

- Our research has shown that these features can best be explained as sand injectites (sand intrusions) as sand flowed like water during a large earthquake

4.) Vertebrate tracks were made on dry desert dunes

- Brand and Tang (1991) demonstrated that the best explanation for the tracks is that they were made underwater

5.) Raindrop prints are common

- We have found that the so-called rain drop prints do not resemble modern rain drop prints. They are deep and lack expected characteristics

6.) The grains were frosted in a desert

- Our research indicates the sand grains are too small to be mechanically frosted and that frosting in this sandstone has occurred via chemical means

7.) Large contorted beds are slumped sand dunes

- We believe these folded beds are best explained as parabolic recumbent folds. They are well-known from subaqueous cross-bedded sandstones

8.) There should be no dolomite

- We found bedded dolomite in the Coconino! (Dolomite beds, ooids, cement, clasts)

9.) There should be no mica

- We found mica in almost every thin section that we looked at under the microscope

10.) Big sand dunes don't occur underwater

- In fact large "sand waves" very comparable to the Coconino sands can be found in many marine settings around the world

favor; myths; underwater

Coconino Sandstone Findings:

- Many features commonly cited in __________ of the desert origin of the Coconino Sandstone are ________

- Many of these features instead argue for ________________ deposition of the sandstone

- This has implications for other cross-bedded sandstones which are supposedly eolian

above water

One of the main arguments for the Pangean supercontinent being ____________ ___________ are Permo-Triassic cross-bedded sandstones in North America and Europe

Petrology

What can we look for in other cross-bedded sandstones?

_________________

- Sorting

- Rounding

- K-feldspar

- Mica

- Dolomite

- Grain surfaces

- Grain size trends

- Lack of mechanical frosting

Sedimentology

What can we look for in other cross-bedded sandstones?

_________________

- Parabolic recumbent folds

- Cross-bed angles

- Current (parting) lineation

- Fluid evulsion features

- Tabular, thin beds (no tongues)

- Rare bottomset and topset beds

- Lack of small scale depositional structures

General

What can we look for in other cross-bedded sandstones?

_________________

- Thickness of deposit

- Paleontology

- Stratigraphic equivalents

- Provenance

- Flat contacts

- Transitional contacts

- Lateral continuity

Metamorphism

- The process by which a rock is changed by heat and/or pressure

- The original minerals of the rock are recrystallized into new minerals during the process

- Melting is never a part of metamorphism

- The metamorphic product usually looks unrecognizable from its parent

metamorphism

Factors controlling the outcome of ______________________:

- Heat

- Pressure

- Chemically Active Fluids

- Parent rack

Metamorphic

_____________________ rocks:

- Regional (caused by heat and pressure)

- Contact or thermal (caused by heat)

- Dynamic (caused by pressure)

crystalline; layers; Melting

Classification of metamorphic rocks:

- They are _______________ , or have interlocking crystals (like Igneous rocks)

- But, the grains are often organized in __________ (foliation), especially if pressure has played a role in the metamorphism

- Don't get foliation mixed up with sedimentary layering; they have a similar appearance, but different origin

- ____________ does not take place during metamorphism; if the rock melts, the liquid will crystallize and it will become an igneous rock

Foliation

Results from minerals growing in preferred directions because of large amounts of pressure during metamorphism, The minerals become "layered" in the rock because of foliation. Can appear as bonds of light and dark minerals.

Grades

___________ of Foliation:

- Shale (a sedimentary rock)

- Slate (low grade metamorphic rock)

- Phyllite (low grade metamorphic rock)

- Schist (high grade metamorphic rock)

- Gneiss (high grade metamorphic rock)

- Migmatite (a partially melted rock)

Regional

______________ Metamorphic rocks:

- Formed by heat and pressure

- Most common, occur over very large areas (often state-sized)

- Low grade --> high grades of foliation

- Slate --> phyllite --> schist --> gneiss

- Degree of foliation increases with grade (minerals get larger)

- All are foliated