GEOL 108Lg 1st EditionExam 1 Study GuideWhat exactly is our Planet's 'crisis'? What is our planet's history of crises• Geo-punctuated events that lead to a feedback in the earth’s systems, then causing rapid changes in the environment.• Crises can be defined by the diversity of life-forms against time. Diversity specifically alludes to the number of families of species. For example, millions of years ago, we knowthat a mass extinction occurred rather abruptly which led to a rapid decline in the diversity of species on Earth.Global Warming: a term use to describe these rapid changes is in part caused by industrialization and natural resource use which speed up the earth’s processes.What are earthquakes?Earthquakes: A sudden movement of the Earth's lithosphere (crust/upper mantle). They're caused by the release of built-up stress within rocks along faults or by the movement of magma in volcanic areas. They are usually followed by aftershocks. California frequently experiences earthquakes.What is the Big Bang Theory?The Big Bang Theory, Background InformationMelvin Slipher came up with what is now known as the Big Bang Theory in 1913. The discovery of 12 galaxies beyond the Milky Way all showed the “red shift”, a doppler effect indicating all were speeding away at high speeds. The theory states that everything began in a small part of space before blowing up and expanding - this formed the Milky Way, Our Galaxy, the Solar System, and then Earth.Doppler Effect: Wave phenomena ex. light/sound wave. If it’s moving towards a subjectthe wave gets squished, and if it moves away from a subject, the wave stretches out. A peculiar example of this is the sound created by an ambulance siren (higher in pitch when moving towards you, lower when moving away)1927: Edwin Hubble confirms Slipher’s observation. The most distant object moved at the largest velocity, meaning that the universe is expanding. 1964: Arno Penzias and Robert Wilson Find Evidence in Support of the Big Bang: At Bell Labs in NJ whilst conducting experiments regarding radio astronomy but could not get rid of abothersome noise signal. They discovered that a constant noise source existed, and that the earth is bathed in a cosmic background radiation that comes from the Big Bang.14 billion years ago, there was a singularity. This is where everything began, and into the void, something went wrong. This caused Quantum Fluctuations, and an initial stage of inflation and expansion. This, in turn, caused a dramatic change - atoms formed, first proton formed - this ledto the development of elements, e.g. P+E=Hydrogen, P+P=Helium). More complex elements were formed by the fusion of lighter elements, e.g. 4He=1 Oxygen. The building up of atoms via nucleosynthesis led to the formation of stars, than galaxies, then planets. Strangely, the galaxies are not distributed evenly, for everything in the universe began a non-linear evolution. At around 400 Million years ago, the first stars were formed after what were known as the Dark Ages. The Solar System• Almost all planets orbit the sun on a common plane, in the same direction. Planetary orbits are almost perfectly circular. The sun has the most mass in the solar system. The Inner Planets are rocky, metallic and solid with iron cores. The Outer Planets are mostly made up of gas and ice. How It All Began: roughly spherical, slowly rotating nebula began to contract, concentrating mass/containing energy associated with spin - conservation of angular momentum let to them speeding up, contracting and rotating like ice skaters. A flat, rapidly rotating disc form, which then spawned chunks of planetary matter, produce what then became planetesimals. The planetesimals attracted particles, and thus the planets were formed. The giant outer planets grew by gas accretion, and are all low density. A protostar was formed, which we now know as our Sun. Planetary configuration: The strong thermal and pressure gradient developed by the early sun evaporated the volatile elements in the inner terrestrial planets and condensed them in the outer gaseous planets. The chemistry of the planets is related to their distance from the Sun. Why, then, is earth able to sustain life?What scientists aptly coin the Goldilocks Zone is also known as the Habitable Zone - this term refers to the region surrounding a star, in this case the Sun, within which it is possible for a planet to maintain liquid water on the surface. Being that liquid water is a vital source for all known lifeforms, a planet that has sufficient atmospheric pressure to maintain water on the planet’s surface - thus requiring it to have a sufficient mass and gravity. It must be far enough away from the sun for the water to condense, and far enough away so it doesn’t freeze (most ofthe time, anyway). Early on, there was no oxygen in the universe. A rise in oxygen after 2.5 billion years has to do with rocks that can incorporate the element. Oxygen is then saturated, leading to a rise inoxygen atoms which then causes an explosion of life. The oceans were formed by early volcanoes.Also important to note: VolcanoesA volcano is essentially any place on where material from the inside of the planet makes its way through to the planet's surface. Some of elemental compounds emitted from a volcano, such as hydrogen, nitrogen and carbon dioxide , are absorbed by the atmosphere, while the water produced goes to the oceans. What are plate tectonics? How do we know the physical structure of the earth using seismic waves (P and S waves)?Seismic waves are any waves that travel through the earth – any kind of large or explosion causes them, sending energy through Earth itself. They are and were crucial to figuring out what the actual composition of the Earth (e.g. its layers, the material that composites the layers,etc.) There are two types of waves: Surface waves and Body waves (also known as S waves and P waves). Body waves are the ones that are used to figure out the earth’s structure, as they are not simply traveling across the surface of a substance. P (Primary) Waves: shakes the ground back and forth in the same direction and the opposite direction as the direction the wave is moving. They can travel through air, liquids, and solids. S (Secondary) Waves: or shear wave, shakes the ground back and forth perpendicular to the direction the wave is moving. S waves ONLY travel in solids.Refraction and ReflectionRefraction of a seismic wave is