Geology 209

Basically everything I could possibly think of to go into a flashcard set. It's a lot.

stratigraphy

Drawing the layers to determine the age relations between rocks

biostratigraphy

Using fossil evidence to draw layers to determine the age relations between rocks

Neils Stenson (nicolas Steno)

Found a shark tooth in the mountains and wrote De Solido to explain his theories. Created his own set of principles.

superpostion

One of Steno’s principles. Deposition of sedimentary layers usually happens under water. If the lower layers are not older than something has happened to disrupt it.

lateral continuity

One of Steno’s principles. Sediments are layered down in flat lateral layers. If the layers are not continuous they must have been eroded.

original horizontality

One of Steno’s principles. Layers were originally laid down horizontally. If the layers are not horizontal, it is evidence of some kind of deformation (bending, folding, doming).

cross-cutting relationships

One of Steno’s principles. Any sign that cross cuts another is necessarily younger than that which it cuts. The fault is younger than the layers because the layers must be there to cut in the first place.

abraham gottlob werner

A neptunist who believed that primary rocks precipitated from a global ocean.

neptunism

Earth began as a planet wide ocean.

james hutton (plutonism)

A plutonist who believed earth started as a molten ball and primary rocks were the first to precipitate. He believed in an eternal Earth and infinite cycles.

plutonism

Earth began as a molten ball.

uniformitarianism

Changes in land appear slow and constant, with the surface always in dynamic equilibrium. It takes forever for big changes to happen. The Earth must have been around for all of eternity. No vestige of a beginning, no prospect of an end.

fossils

Preserved plants, animals and life matter. Preserves the “hard parts” of animals with pressure.

william smith

Designed canals, used fossils to connect layers over space. The thickness of layers tells us how long a period lasts.

mineralization

A type of fossilization. Trees get covered with volcanic ash, ammonite swims and dies and ends up at the bottom of the ocean, where the sediments harden making a mold(replacement), etc

index fossils

The most useful fossils for identifying how old a rock is. The smaller the layer it’s in, the easier to identify the specific time where they live. Need to be widespread in order to be useful

mary anning

Found many fossils that proved signs of former life and very different ecosystems from now, most people were skeptical and she didn't get much credit for her findings.

george cuvier

Used fossils to understand past environments. Founder of catastrophism.

catastrophism

Periodic revolutions of change.

lamarckian evolution

Change happens through time. Can happen during an individual's life.

darwinian evolution

Environmental pressure causing change. Diversity decides whether you live or not. Darwin watched how finches changed and evolved in the galapagos island.

cuvier evolution

Did not believe species changed. Species are born suited for their environment. Never explained where new species came from

maps

Visual representations or models showing relationships between or among objects or concepts. The way a map looks depends on its purpose.

geradus mercator

Came up with longitude and latitude.

geological maps

Signs in the rocks helped connect them across space. Helped to interpret history (environment). Vertical changes helped to identify changes through time. Geological maps show elevation/topography, The geology at the surface (interpolated), The subsurface geology (extrapolated), time/history (subbing space for time), and connecting areas together.

jean de charpentier

Inferred that large continental scale glaciation had occurred in the past.

louis agazzi

Became an advocate for a slowly cooling Earth with periodic ice ages. Hole in his theory - how did we get glaciers when it was hotter than it is now??

glacier

Snow builds upon itself until it packs together. Water expands when it freezes. When you crush ice, it will turn it back into water. The little amount of water in between ice crystals allows glaciers to slide.

terminal moraine

Land that gets pushed forward by the glacier.

lateral moraine

Land that gets pushed to the side by the glacier.

alpine glacier

Glaciers flow through to create valleys.

continental glacier

Just a different magnitude than alpine glaciers but the same mechanism.

actualism

Thousands of years of boredom (uniformitarianism) punctuated by moments of sheer terror (catastrophism). Uniformitarianism + catastrophism.

isostatic rebound

Isolines represent the rate, in mm per year, the surface is “springing” back. Supports continent wide glaciation. Gives us a clue on how the inside of the Earth works - Mantle is more dense than the lithosphere, Pushes lithosphere up, Mantle is solid, but flows overtime.

james ussher

His chronology was picked for the king james bible - “in the beginning god created heaven and the earth”

johannes keppler

Not science vs religion, just a line of inquiry about how the earth was formed etc.

weathering

Breaking down Earths science further. Chemical - different material, Mechanical - physical.

chemical weathering

Becomes a different material.

mechanical weathering

A physical change.

epiliths

In chemical weathering in organisms, epiliths are the most recent things to be broken down, on top.

endoliths

In chemical weathering in organisms, endoliths are the least recent things to be broken down, on the bottom.

hydrolysis

A type of chemical weathering. Water becomes chemically attached to a molecule, creating a new molecule.

oxidation

A type of chemical weathering. Oxygen combines with iron to form iron oxide (rust)

dissolution

A type of chemical weathering. Water dissolving stuff - rain water, acid rain etc.

root pry

A type of mechanical weathering. cells filled with water create a high amount of pressure. Water filling growing cells break the rock into smaller pieces.

frost wedging

A type of mechanical weathering. Water expands when it freezes and breaks the crack (over and over).

exfoliation

A type of mechanical weathering. Does not require water. Consistent thermal change causes alternation between thermal contraction and thermal expansion at the very surface, resulting in breakage of the rock in characteristically thin layers. Wind blows/carves rock, water can cut through rock, but also move it.

gravity vs friction

Once stuff is broken down, gravity pulls stuff down, and friction impedes motion. When friction wins, stuff stays put.

v shape valleys

Valleys eroded by rivers

deposition

When friction wins back the battle. Usually in a large body of water. Sediment laden water is denser than pure water. Produces current that flows on the bottom of a body of water.

claim

Propositional statement. Statement of conclusion. Something we believe to be true based on evidence.

evidence

Observations that support a claim.

assumption

Things we believe to be true or accurate without evidence. generalizations.

edward lhywid

Walked along a glacial valley (not knowing it was glacial). Observed boulders on the valley floor. Assumed boulders falling was rare. Proposed that it must have taken a couple hundred thousand years for all the boulders to fall.

edward halley

Postulated that if one could find a lake with no river exit and measure the saltiness, one could determine the age of the Earth, assuming the lake had fresh water to start with and has a constant influence of dissolved salts. Never performs test as he does not have accurate tools.

benoit de maillet

Considered seashells in mountains as evidence for an original global flood. Since the water must be evaporating at a constant rate, if he could measure the lowering of sea level, assuming constant rate of evaporation, he could calculate the age of the Earth.

George Louis, leclerc, comte de baffon

Used his iron foundry to create iron spheres of different diameters. Heated them up almost to melting, Timed their cooling, and Used the results to calculate the age of the Earth

top-down approach

starting with a ‘set of rules’ and interpreting the world through them

bottom-up approach

starting with a bunch of observations and working up to create ‘rules.’

scientific theory

An explanation (not description) of a particular phenomenon. Tells us why or how. Just as dependable as scientific laws. Theories do not become laws

scientific law

Description of behaviors of some portion of the universe as a general rule or mathematical equation. Normally developed through many observations, usually through experiments. ‘Law’ in this case is a metaphor. Dictates how nature is supposed to behave.

amelia maggia (mollie)

Died of radiation poisoning in a factory and was the start of people realizing that radium is in fact poisonous

atom

Neutrons and protons in the nucleus, Electrons on the outside

Electron mass = 0, Proton mass = 1, Neutron mass = 1

Atoms are defined by the number of protons they have.

isotope

The same element with different numbers of neutrons, affecting the stability.

alpha decay

A type of decay where the atom gives away two protons and 2 neutrons. Radiation is just being shot by protons and neutrons as the atom tries to become stable.

parent element

Decays or breaks down into the daughter element.

daughter element

The result of the parent element breaking down.

half-life

The time it takes for an element to break down into half of its size.

carbon dating

Uses half-lives and radioactive isotopes to determine the age of the earth.

preservation

Rocks are continually recycled, metamorphosed, eroded. Chapters are continually torn from the book.

erosional deposition

The rate that a mountain decomposes

aristotle (porous earth)

Earth is made up of rocky materials with networks and caverns and galleries through which fluids can flow. Where fluids accumulate, it fills the caves, creating uplands. Where fluids are low in volume, Earth sinks into ocean basins. As fluid flows back and forth, transition zones see earthquakes and volcanic activity. Like a sponge.

Hutton (vertical displacement)

Earth's internal heat engine caused vertical movement of heat.

edward seuss

Sees folded sedimentary rock in the alps. The Earth is molten, and the first to cool is the outside (because it is the closest to space, obviously). The matter contracts as it cools. Homogenous crust, meaning oceans and continents can alternate.

james dana

sees folding mountains. believes in a contracting earth. The least dense rocks cool first. Low density rocks are continents, high density rocks sink down and become the basin. Lows get lower, highs get higher. Heterogenous crust, meaning oceans and continents can’t alternate.

biological disjuncts

Biological similarities on disconnected continents

schuchert

Came up with broad land bridges.

willis

Came up with isthmian links.

horizontal displacement

Wegener matches the continents together like a puzzle. Biological and geological disjuncts match, as well as mountain ranges. It was hard for people to believe as it went against everything everyone knew at the time.

alfred wegener

Came up with horizontal displacement/ pangea

mobilist

Believes in vertical displacement.

fixist

Believes in horizontal displacement.

contraction theory

Essentially the Earth is getting smaller which is causing folded mountains

edna plumstead

Studied fossils and came up with the Gondwanaland connections

alexander du toit

Studies maps in south america that matches fossils etc. found in west africa.

homogenous crust

All of earth's crust is the same which allows for shifting continents and oceans. This is incorrect.

heterogenous

Continents and oceans have different crust. This is correct.

pratt

Continental rocks get less dense toward the middle of continents causing them to “float” higher on interior layers of the Earth

george biddel airy

There are hidden “roots” of low density mountain material causing the mass deficit.

isostacy

A fancy word for buoyancy.

earthquake

Initially thought to be of divine cause. A release in elastic energy when a brittle rock fails. The release of energy causes the shaking.

seismology

Used to track and measure earthquakes

robert mallet

Measured direction of cracks to determine location of earthquake. Seismic description of destruction

harry fielding reid

Studied regional deformation as recorded by past surveys. The crust deformed elastically under some kind of stretch. The rocks with stood a certain amount of strain before the break. Rocks go back to their original configuration (snaps back elastically).

p-wave

primary (first) compressional waves. In vertical motion, p-waves are bigger.

s-wave

secondary (second) shear waves. In horizontal motion, s-waves are bigger.

body waves

Travel through the body of the earth

surface waves

Travel through the surface of the earth. Slower than s and p waves, horizontal motion only.

love waves

A type of surface wave. kind of equivalent to p wav

rayleigh waves

A type of surface wave. Circle. These are what knock buildings down.