5572/5571 Praxis Earth and Space Science Study Set

Pangaea

The name of the single landmass that broke apart 250 million years ago (Permian) and gave rise to today's continents

Continental Drift- Triassic

Triassic 200 million years ago. The Tethys Sea is created between Laurasia (north) and Gondwanaland (south and east)

Continental Drift- Jurassic

Jurassic 145 million years ago. India has broken off of Gondwanaland

Continental Drift- Cretaceous

Cretaceous- 65 million years ago

Isochron Map

A contour map that displays the variation in time between two seismic events or reflections.

Evaporite Mineral

A sedimentary deposit that is left behind when water evaporates; includes gypsum, calcite, and halite.

Why are the bands on the East Pacific Rise wider on an isochron map than the bands on the Mid-Atlantic Ridge?

Spreading along the East Pacific Rise is greater than the spreading along the Mid-Atlantic Ridge

What is granite composed of?

granite is composed of orthoclase feldspar, quartz, biotite, plagioclase feldspar, plagioclase feldspar.

Bowen's Reaction Series

the simplified pattern that illustrates the order in which minerals crystallize from cooling magma according to their chemical composition and melting point

Why is a plagioclase crystal in an igneous rock calcium rich in the center but becomes progressively higher in sodium content towards the edges?

Calcium-rich plagioclase crystalizes at higher temperatures, and sodium-rich plagioclase crystallizes at lower temperatures. The crystals grow outward as the magma cools.

Examples of Igneous rocks

Obsidian, granite, basalt, pumice, gabbro

Examples of Sedimentary rocks

sandstone, breccia, limestone, conglomerate, shale

Examples of Metamorphic rocks

schist, slate, marble, quartzite, gneiss (pronounced "nice")

Two examples of covalent network solids

C (diamond) and SiO2 (quartz)

How is sedimentary rock formed?

formed from sediments being compressed by other overlying sediments. Compact and cement sediment.

How is metamorphic rock formed?

heat and pressure

How is igneous rock formed?

cooling of magma

The Rock Cycle

A series of processes on the surface and inside Earth that slowly changes rocks from one kind to another

Examples of rocks that fizz on the acid (HCl) test.

Limestone, sandstone, breccia, conglomerate, shale, marble, halite, feldspar, calcite, dolomite (carbonate minerals)

Examples of minerals

quartz, talc, magnetite, halite, feldspar, gold, diamond, silver, copper, mica, amethyst

Examples of silicates

Quartz, feldspar, olivine, talc, mica

Examples of Halides

halite, fluorite, sylvite

Examples of phosphates

Apatite

Examples of carbonates

calcite, dolomite, malachite, aragonite

Examples of sulfides

galena, pyrite, bornite

Examples of sulfates

Gypsum, barite

Examples of Oxides

magnetite and hematite

What do unconformities in the rock record represent?

Time intervals that are not recorded in the geologic record at that location

Why is quartz common?

Quartz is relatively stable in conditions found at Earth's surface

How have atmospheric concentrations of carbon dioxide changed over time?

What is the Mohs hardness scale?

A scale which rates minerals from softest (1) to hardest (10)

What mineral is the softest (1) and hardest (10) on Mohs hardness scale?

Softest (1): Talc Hardest (10): Diamond

What are the differences between Gold and Pyrite (fool's gold)?

Pyrite is notably harder than gold. Pyrite often forms in cubes, while gold does not. Gold will leave a yellow streak, while pyrite will leave a darker, greenish-black one. Pyrite has sulfur, meaning it will have a faint smell, while gold is odorless.

What are the differences between fluorite and quartz?

Quartz is harder than fluorite and will scratch fluorite. Fluorite also often has a cubic pattern, will quartz does not.

What is specific gravity?

the ratio of the density of a substance to the density of water

How old is Earth?

4.6 billion years old

What did Earth look like in the Hadean Eon?

Molten Earth 4-4.6 billion years ago

What did Earth look like at the end of the Proterozoic?

Snowball Earth 640-710 million years ago

When was the Great Oxidation?

2.5-3.8 billion years ago (Archean)

When were the first multi-celled organisms created?

Proterozoic

When were the first shelled organisms created?

Cambrian (520 million years ago). Brachiopods, arthropods, mollusks, chordates

Ordovician-Silurian Mass Extinction

The third largest extinction in Earth's history, the Ordovician-Silurian mass extinction had two peak dying times separated by hundreds of thousands of years. During the Ordovician, most life was in the sea, so it was sea creatures such as trilobites, brachiopods and graptolites that were drastically reduced in number.

Devonian Mass Extinction

resulted in major ecological restructuring with particular emphasis on reef systems. Wiped out 3/4 of all species.

Permian-Triassic Mass Extinction

"The Great Dying", ~95 % of all life went extinct, reptiles became dominant life form

When were the first reptiles?

Paleozoic, more specifically the Pennsylvanian

Triassic-Jurassic Mass Extinction

During the final 18 million years of the Triassic period, there were two or three phases of extinction whose combined effects created the Triassic-Jurassic mass extinction event. Climate change, flood basalt eruptions and an asteroid impact have all been blamed for this loss of life.

When were the first dinosaurs?

During the Triassic ~230 million years ago, also the first mammals

Cretaceous-Tertiary Mass Extinction

The Cretaceous-Tertiary mass extinction - also known as the K/T extinction - is famed for the death of the dinosaurs. However, many other organisms perished at the end of the Cretaceous including the ammonites, many flowering plants and the last of the pterosaurs.

When was the last Ice Age?

Pleistocene Epoch, ended ~11,500 years ago

What are the Eons in order from oldest to most recent?

Hadean, Archean, Proterozoic, Phanerozoic

What are the eras in order from oldest to most recent?

Precambrian, Paleozoic, Mesozoic, Cenozoic

What are the periods from oldest to most recent?

Cambrian, Ordovician, Silurian, Devonian, Mississippian, Pennsylvanian, Permian, Triassic, Jurassic, Cretaceous, Tertiary (Paleogene, Neogene), Quaternary

What are the Epochs from oldest to most recent? Hint: all of the Epochs are in the Cenozoic Era.

Paleocene, Eocene, Oligocene, Miocene, Pliocene, Pleistocene, Holocene

What are the three types of galaxies?

spiral, elliptical, irregular (lenticular)

Who described galaxies by their shape?

Hubble

What is the order of the planets in our solar system?

Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune

What are the approximate distances of each planet from the sun?

What is the Kuiper Belt?

a region of the solar system beginning just beyond the orbit of Neptune that contains many icy comets

What is the Oort Cloud?

a spherical shell around the solar system formed by comets with long orbital periods

How are dark line spectra used?

The dark lines we see in a spectrum correspond to certain wavelengths that are missing due to absorption by matter in the form of atoms/molecules. The dark line represents "absence of light" in a spectrum, not any particular wavelength of light

Why do most astronomers think that the Big Bang Theory is the best explanation of how the universe formed?

1. Hubble's discovery of a relationship between a galaxy's distance from Earth and its speed in the 1920s. 2. The discovery of cosmic microwave background radiation in the 1960s.

What is the Big Bang Theory?

the idea that all matter and energy in the universe began in an unimaginably dense state, and then space itself began expanding

What are Cepheid variable stars?

Cepheid variable stars are intrinsic variables which pulsate in a predictable way. In addition, a Cepheid star's period (how often it pulsates) is directly related to its luminosity or brightness. For example, if two Cepheid stars have the same period but one is fainter than the other, then that one must be farther away.

What is parallax?

the apparent change in position of an object when you look at it from different places

What is a black hole?

a region of space having a gravitational field so intense that no matter or radiation can escape.

What are Milankovitch cycles?

changes in Earth's orbit and orientation to the Sun

Eccentricity

Earth's orbit being more elongated or circular around the Sun.

Axial Tilt

The angle that a planet's axis is tilted from vertical. Right now Earth is tilted 23.5º. The greater the tilt, the more solar energy the poles receive.

Precession

Wobble in Earth's rotational axis

apparent magnitude

the brightness of a star as seen from Earth (1- brightest; 6- dimmest)

Hertzsprung-Russell diagram

a graph relating the surface temperatures and absolute brightness of stars

How is a star's color related to its temperature?

red stars are cool, blue stars are hot

How do stars form?

A cloud of dust and gases collapse under the force of gravity and create a Protostar. Pressure causes nuclear fusion to begin.

Kepler's First Law

The orbit of each planet around the Sun is an ellipse with the Sun at one focus.

Kepler's Second Law

As a planet moves around its orbit, it sweeps out equal areas in equal times

Kepler's Third Law

The square of the orbital period of a planet is directly proportional to the cube of the semi-major axis of its orbit.

meteor

a small body of matter from outer space that enters the earth's atmosphere, becoming incandescent as a result of friction and appearing as a streak of light.

Meteoroid

a relatively small, rocky body that travels through space

meteorite

A meteoroid that passes through the atmosphere and hits Earth's surface.

Origin of meteoroids

Kuiper Belt, Oort Cloud, collisions of asteroids, comets

Why are comets referred to as dirty snowballs?

The consist mainly of ice, with rocky debris and frozen gases.

retrograde motion

The apparent motion of the planets when they appear to move backwards (westward) with respect to the stars from the direction that they move ordinarily.

Copernicus

1473-1543. Polish astronomer who was the first to formulate a scientifically based heliocentric cosmology that displaced the earth from the center of the universe. First to propose that the apparent retrograde motion of some planets was best explained with a heliocentric model of the solar system.

Isaac Newton

Defined the laws of motion and gravity. Tried to explain motion of the universe. One of the first people to make a reflecting telescope.

Newton's First Law

An object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force.

Newton's Second Law

Force = mass x acceleration

Newton's Third Law

For every action there is an equal and opposite reaction

Galileo

Italian astronomer and mathematician who was the first to use a telescope to study the stars. Observed the moon, phases of Venus, moons around Jupiter, sunspots, and the news that seemingly countless individual stars make up the Milky Way

Tycho Brahe

Influenced by Copernicus; Built observatory and collected data on the locations of stars and planets for over 20 years; His limited knowledge of mathematics prevented him from making much sense out of the data. Discovered a new star in the Cassiopeia formation.

Kepler

This astronomer stated that the orbits of planets around the sun were elliptical, the planets do not orbit at a constant speed, and that an orbit is related to its distance from the sun.

solar eclipse

Occurs when the Moon passes directly between the Sun and Earth and casts a shadow over part of Earth. Can only happen during a New Moon

lunar eclipse

the blocking of sunlight to the moon that occurs when Earth is directly between the sun and the moon. Can only happen during a Full Moon

Why do seasons occur?

The tilt of Earth's axis causes sunlight to fall differently on Earth at different times of the year

Doppler effect

An observed change in the frequency of a wave when the source or observer is moving

Cosmic Microwave Background Radiation

electromagnetic radiation that has been traveling through space ever since it was created shortly after the Big Bang

Elemental composition of the universe

hydrogen and helium

Redshift

shift of light to a longer wavelength as it moves away

Blueshift

A Doppler shift in which spectral features are shifted to shorter wavelengths, observed when an object is moving toward the observer.

How old is the universe?

14 billion years old

dark matter

matter that does not give off electromagnetic radiation but is quite abundant in the universe