ES 104 Final Exam Study Guide

The most recent homework activities on igneous compositions and volcano types will be valuable study materials for the upcoming exam.

The handout with a table comparing the 3 igneous compositions will also be a valuable study tool (will be handed out during the last week of lecture).

Lecture 9:

Earth materials

Parameters that define a mineral

Definition of a rock

Silicate Minerals and Earth’s Composition

Know which two elements are the most abundant in Earth’s Crust.

Know what silicate minerals are and that their fundamental building block is the silicon tetrahedron.

Know that silicate minerals make up most rocks in the Earth’s crust.

Know that the 2 most abundant silicate minerals in continental crust are feldspar and quartz.

Lecture 10:

The 3 categories of rocks – Igneous, Sedimentary, and Metamorphic

Know how rocks of each group are formed.

Igneous Rocks and Properties:

Know what magma is.

Magma materials – melt, mineral crystals, and volatiles

Intrusive vs. extrusive igneous rocks – know where they are formed and the differences in their cooling rates.

Know the relationship between cooling rate and crystal size in igneous rocks.

Be familiar with the following igneous rock texture terms – fine-grained, coarse-grained, porphyritic, frothy, glassy, vesicles.

Be familiar with the following igneous rock compositions – felsic, intermediate, mafic, ultramafic.

Know that the amounts of light and dark colored silicate minerals can indicate an igneous rock’s composition.

Know which igneous compositions have the greatest amount of silica (SiO2) and which have the least.

Know what igneous rock compositions make up continental crust and oceanic crust.

Know what rock type makes up Earth’s upper mantle.

Light vs. Dark silicate minerals in the Bowens reaction series – know which crystallize at higher and lower temperatures.

Based on the Bowens Reaction Series, know which igneous rock compositions have the higher and lower melting/crystallization temperatures.

Origins of Magma:

Be familiar with how magma is formed at divergent (oceanic ridges) and convergent (subduction zones) plate boundaries.

Know the common compositions of magma erupted at oceanic ridges vs. subduction zones.

Know what magma compositions are formed from partial melting of mantle rocks vs. partial melting of continental crust.

Lecture 11:

Intrusive Igneous Activity

Know what intrusions (plutons) are.

Types of intrusions (plutons) – dikes, sills, laccoliths, batholiths, volcanic necks – be familiar with the general shapes of the different types of intrusions.

Volcanic Material

Know that magma viscosity and the amount of dissolved gases determine how explosive volcanic eruptions are.

Know how composition (amount of silica) and temperature affect magma viscosity.

Know which igneous compositions have the greatest and lowest viscosity.

Know the effects of viscosity on the nature of volcanic eruptions (explosive vs. non-explosive)

Know the effects of viscosity on lava flows (mafic, intermediate, and felsic lava flows).

Felsic vs. Mafic lava flows – remember that the shape and extent of these lava flows is determined by differences in viscosity.

Basaltic lava flows – know the difference between pahoehoe and aa.

Pyroclastic materials – know the differences between lapilli, ash, bombs, and blocks.

Be familiar with the following volcanic structures:

Vent, crater, caldera, volcanic cone, fumaroles

Lectures 12-13:

Volcano Types

Shield volcanoes – know the common composition of lavas, types of eruptions, general structure and shape.

Examples: Mauna Loa and Kilauea in Hawaii –hotspot volcanism

Composite cones – know the common compositions of lavas, volcanic materials, types of eruptions, general structure and shape.

Example: The Cascades and the Ring of Fire – Subduction zones (convergent plate boundaries)

Know that composite volcanoes can be the most potentially dangerous.

Cinder cones– know what volcanic materials they are composed of, types of eruptions, general structure and shape.

Know that cinder cones are small, simple volcanoes that only erupt once.

Know that greater viscosity lavas form steeper-sided volcanic cones such as composite cones.

Know that lower viscosity lavas form shield volcanoes.

Volcanic Hazards associated with Composite Cones such as those in the Cascades:

Pyroclastic flows – definition, properties, and causes.

Lahars – definition, properties, and causes.

Ash-fall – know why heavy ash fall and ash clouds can be hazardous.

Volcanic landslides – be familiar with what triggered the May 18, 1980 eruption of Mount St. Helens.

Caldera forming eruptions – know how calderas are formed and examples of each:

Crater Lake type calderas – see Lecture 13

Yellowstone type calderas – see Lecture 13

Shield volcano calderas – see Lecture 12.

Flood Basalts

Caused by large-scale fissure eruptions.

Example in the Pacific Northwest - Columbia River Basalts

Questions on concepts covered in the first two sections of the course will most likely include the following topics:

Weeks 1 and 2:

Classical astronomy concepts

Know Kepler’s 3 laws of planetary motion.

Know what an Astronomical Unit (AU) is.

Know that orbits result from a combination of inertia and gravitational attraction.

Week 2:

The Solar System

Jovian planets versus the Terrestrial planets – be familiar with the basic physical and compositional differences between these 2 categories of planets.

Know how the orbital spacing of the planets changes with distance from the Sun.

Know the difference between the dwarf planets and the 8 official planets.

Be familiar with the Nebular Hypothesis for the origins of the Solar System.

Weeks 3 and 4:

Properties of Light

Know that different colors in the light spectrum are associated with different wavelengths (violet = short, red = long).

Know that the composition of stars can be determined from the spectrum of light that they emit.

The Sun

Know that the Sun is an average-sized yellow star.

Be familiar with the source of the Sun’s energy – nuclear fusion reactions in the Sun’s core where H nuclei are combined to form He nuclei.

The Stars

Know that the brightnessof a star is affected by its temperature and size.

Know what a light year is.

Know the relations between a star’s temperature and its color.

Know what will happen to the Sun when it reaches the end of its life cycle.

Know that black holes and neutron stars could form when a massive star undergoes a supernova explosion.

Week 4:

Earth’s Internal Structure

Compositional layering – crust, mantle, core

Layering based on physical properties – lithosphere, asthenosphere, lower mantle, outer core, inner core

Be familiar with the general physical and compositional properties of the Earth’s layers.

Know that the lithosphere includes the crust and the upper most mantle rocks.

Know that the asthenosphere is solid but is soft and capable of gradual flow.

Know that the only layer that is completely molten is the outer core.

Know the differences between continental crust and oceanic crust (thickness, composition, etc.)

Know why continentals are more elevated relative to the ocean floor.

Week 5:

Be familiar with the Theory of Plate Tectonics – lithosphere is divided into plates that move about on the soft, gradually flowing rocks of the asthenosphere.

3 Types of Plate Boundaries – Be familiar with the plate motions that occur along each of these:

Divergent boundaries – mid-ocean ridges and continental rifts.

Know that new lithosphere forms along mid-oceanridges – sea floor spreading.

Convergent boundaries – subduction zones and continental collisions.

The return of lithosphere to the mantle occurs along subduction zones.

Know that volcanic arcs form along subduction zones (such as the Cascades).

Know what The Ring of Fire is.

Surface expressions of subduction zones – deep-ocean trenches.

Know that a subduction zone is offshore from the Pacific Northwest and that the Cascade volcanoes are associated with this plate boundary.

Know that the largest magnitude earthquakes on record have occurred along subduction zones.

Examples of mountain ranges formed by continental collisions – Himalayas and Alps.

Transform boundaries:

Know that most transforms divide mid-ocean ridges into segments.

Know that the San Andreas Fault in California is a transform boundary.

Hotspots:

Know what a hotspot is and what causes hotspots (rising mantle plumes).

Hawaii and Yellowstone are examples of volcanic features located on hotspots.

Know that the Hawaiian island chain formed as the Pacific Plate moved over a stationary hotspot.

Weeks 6 and 7:

Earthquakes

Know the theory of elastic rebound – causes of earthquakes along faults.

Know these terms: faults, hypocenter, and epicenter.

Know that most earthquakes occur along the boundaries between tectonic plates.

Be familiar with P and S waves and the type of motion associate with each as well as what materials each can pass through.

Know that on the Richter scale, an increase of 1 magnitude = 32 times more energy released.

Know how an earthquake’s moment magnitude is determined.

Earthquake damage and hazards:

What factors determine the amount of damage that an earthquake can cause?

Know that steel-reinforced and wood-frame structures withstand earthquakes better than unreinforced concrete and brick type structures.

What is liquefaction?

What are Tsunami waves and how are they formed - what type of seafloor movement would result in a Tsunami wave?

Know that earthquakes along subduction zones can produce Tsunamis.