Module 1 Geology

In the three months following the 1991 Mt. Pinatubo eruption, how many lahars occurred?

200

The size of the mineral grains inside of an igneous rock is primarily controlled by

cooling rate of the rock

Horizontal intrusion

sill

Resurgent Dome

magma gasses renters chamber, lifts floor of caldera/ceiling of a magma chamber (often found inside calderas) (secondary post eruption)

Olivine Chemical Formula

(Mg,Fe)2SiO4

Inner Core

Solid, metallic, most dense

Mt. Pinatubo, Phillapines erupted on June 15, 1991. How high was the ash column that ejected from the volcano?

35 km

Our understanding of the Earth's deep interior (mantle & core) comes from (SELECT ALL THAT APPLY)

- areas where mantle rocks have been brought to the surface - meteorites that have fallen to Earth from space - seismic wave profiles of the Earth's interior - presence of a magnetic field surrounding the Earth

How do you form magma?

1. High temp 2. Low pressure 3. High water content

"Year without Summer"

1816, Mt. Tambora in Indonesia, climatic cooling event and volcanic winter

Kilauea volcano located on the big island of Hawaii has been erupting since ______.

1983

How long after the eruption of Mt. Pinatubo did the climatic effect last?

3 years

The current scientific estimate for the age of the Earth is

4.56 Billion years

How many people died in the May 18, 1980 eruption of Mt. St. Helens?

57

The radius of the Earth is approximately

6,371 km

Volcanic Crater

A funnel-shaped depression from which gas, tephra, and lava are ejected. (S-P Crater, AZ)

Anion

A negatively charged ion

Cation

A positively charged ion

Which minerals on Bowen's reaction series might you expect to find in diorite?

Amphiboles, Biotite & Na-rich feldspars (Albite)

Calcite Chemical Formula

CaCO3

Mica has distinct

Cleavage (cuts in sheets)

What are the two cooling features?

Columnar Joints and Pillow Basalts

Who figured out the radius and circumference of the earth?

Eratosthenes

Which of the following silicate minerals contain the highest amount of silica?

Framework

What three igneous rocks are intrusive?

Granite (felsic), Diorite (Intermediate), Gabbro (Mafic)

In professor Nick Zentner's 2-minute geology video on Columbia river flood basalts, the rocks are similar in chemistry to the ______________ volcano and more similar in age to the ________________ volcano.

Hawaiian, Yellowstone

Who figured out the density of the earth?

Henry Cavendish

Who came up with the Principle of Uniformitarianism?

James Hutton

According to Bowen's reaction series, which pink-colored feldspar mineral is most felsic and most stable at the Earth's surface?

K-rich (potassium) feldspar

Which interior Earth layer is the thickest?

Mantle

Double Chain Silicates

Mineral group called amphiboles

Single-Chain Silicates

Mineral group called pyroxenes

Cindercone Volcanoes

More explosive than Hawaii, strombolian eruption style, may eject showers of lava 100 ft in air

Which volcanic eruption has a higher VEI number? (Kilauea, HI) (Soufriere Hills, Montserrat (Caribbean), or (Mt. Pinatubo, Philippines)

Mt. Pinatubo, Phillipines

What is the name of this black glassy mineraloid that breaks along curved surfaces known as conchoidal fracture?

Obsidian

The idea that during Earth's early formation, the densest materials inside the Earth sank to the core and the lighter materials rose to the surface and cooled is attributed to the

Planetary Differentiation Model

What terms explain diorite?

Plutonic, Phaneritic, Intermediate composition.

The 79 AD eruption of Mt. Vesuvius, Italy killed more than 20,000 people in the ancient city of

Pompeii

What three igneous rocks are extrusive?

Rhyolite (felsic), Andesite (intermediate), Basalt (Mafic)

The mineral Quartz has the specific chemical formula

SiO2

Igneous Intrusions

Sill (horizontal intrusion of magma), Dike (vertical intrusion of magma)

Select the proper sequencing order of geologic time periods (from oldest to youngest)

Triassic, Jurassic, Cretaceous

Lava is magma that has reached the Earth's surface.

True

The VEI scale stands for Volcanic Explosivity Index.

True

The phanaritic equivalent of a basalt is a gabbro.

True

Geyser

a natural spring showing intermittent water and steam discharge ("old faithful" Yellowstone)

Mt. St. Helens volcano of the Cascades volcanic mountain range in the Pacific Northwestern US is a stratovolcano that produced __________ on May 18, 1980.

a lateral blast

After the May 18, 1980 eruption of Mt. St. Helens, time-lapse video footage from inside the crater showed what happening?

a lava dome growing

The current scientific estimate of the age of the Earth comes from radiometric age dating of

a meteorite

Hot Spring

a spring that is produced by the emergence of geothermally heated groundwater from the Earth's crust (Grand Prismatic Yellowstone)

Which igneous rock type would you expect to find around Mt. St. Helens & the Cascades stratovolcanoes? (Hint: where the mafic Juan de Fuca oceanic plate subducts beneath the felsic North American continental plate & forms intermediate composition magma)

andesite

A volcanic eruption is an exchange of matter primarily between which two Earth systems?

atmosphere, geosphere (solid earth)

The Hawaiian volcanic islands are made out of the igneous rock ___________.

basalt

Difference between biotite and muscovite?

biotite is intermediate in silica, muscovite high in silica

Xenolith

chunks that don't belong

In 1943, Paracutin, Mexico a ____________________ volcano grew within a week.

cindercone

A mineral has _______________ when it breaks along dimensional (1-D, 2-D, 3-D) planes of atomic weakness.

cleavage

Which layer of the Earth is the least dense?

continental crust

Subduction Zones

convergent plate boundaries, oceanic plate vs. continental plate (Juan de Fuca)

After the June 15, 1991 eruption of Mt. Pinatubo, large amounts of SO2 gas was emitted. This gas combines with H2O vapor to created sulfuric acid aerosols that have a ___________ effect on global climate.

cooling

Columnar Joints

cooling features within lava flow or igneous intrusion formed due to stress as the cooling magma or lava contracts inward (6 sided) (Giant's Causeway-Northern Ireland)

Mafic silicate minerals tend to be _________ in color, while felsic silicate minerals tend to be __________ in color.

dark, light

At divergent plate boundaries, there tends to be volcanoes. Magma is formed at those tectonic locations because of

decompression melting

If a calcite (CaCO3) xenolith, broke off and tumbled in and mixed/melted into a magma chamber, what might that do to the Silica content of the magma?

decrease the Silica content

Vertical Intrusion

dike

The mineral calcite (SELECT TWO):

dissolves & effervesces CO2 gas in an acid and is the primary mineral in the sedimentary rock Limestone.

When two tectonic plates pull apart from one another it is called a ____________ plate boundary.

divergent

Spreading Centers

divergent boundaries where plates are ripping apart (decompression melting)

The mineral Calcite is easily distinguishable because it

effervesces CO2 gas in the presence of an acid

______________ are negatively-charged subatomic particles. that occupy in shells or clouds outside an atom's nucleus.

electrons

Andesite is an igneous rock that is:

extrusive, volcanic, aphanitic, formed from quick-cooling magma, composed of amphiboles, biotite mica & Albite

All hotspot volcanoes are explosive.

false

Jet black obsidian (volcanic glass) is often found near and around the black basaltic volcanic rocks of the Hawaiian islands.

false

Volcanoes always have a conical (upside down ice-cream cone) shape.

false

Water is considered a mineral.

false

Framework Silicates

feldspar and quartz

Generally speaking, if a magma (melt) is high in silica content (>65%), the more _________the magma.

felsic, high viscousity, gas trapping, explosive

The Yellowstone Supervolcano has a magma more______ than Hawaiian volcanoes.

felsic, viscous, explosive

The primary difference between the igneous rocks granite and rhyolite is

grain size (crystals)

The shape of the Earth is a spheroid due to the competition of _______ and ________ forces.

gravitational, centrifugal

Hot Spots

heat from core, Hawaii, and Yellowstone

Hawaii and Yellowstone volcanoes are similar in that they are both___________ volcanoes.

hot spot

Kilauea volcano of the Hawaiian islands is a _________ volcano.

hot spot

Fumaroles

hydrothermal vents - emit steam

A gabbro sill would form

inside the earth (intrusive)

According to Bowen's Reaction Series, olivine is a(n) ________ silicate, that crystallizes _______ in a cooling magma chamber and is _________ at the Earth's surface.

isolated, first, unstable

What is special about volcanic lightning?

it presents horizontally across the sky

A _____________ is a large, mushroom-shaped igneous intrusion.

laccolith

The capital city of Plymouth on the Carribbean island of Montserrat was buried by a volcanic mudslide called a _______.

lahar

Volcanic ash that becomes water-saturated after rainfall events turn the ash into a volcanic mudflow called a

lahar

What hazard? 1985 Armero Tragedy, Columbia, S. America, kills 23,000

lahar

The mineral pyrite (fool's gold) can be easily distinguished from elemental gold (Au) by

leaving a distinctive dark streak across a ceramic streak plate

Relative to a theory, an hypothesis has:

less certainty

In order to be considered to be high in viscousity, what are two things that are required:

low temp and high in silica

According to Bowen's Reaction series, white mica (muscovite) crystallizes from a melt at a(n) _________ temperature compared to black mica (biotite).

lower

A super eruption could produce a climatic event that could ___________ global temperatures by several degrees Celsius and last _____- years.

lower, 4-5

The strongest seismic discontinuity (the speed of seismic waves changes) occurs at the

mantle-outer core boundary

In class we calculated the density (D=M/V) of a small piece of sedimentary sandstone. We measured the mass of the sandstone on a small balance (scale). Next we measured the sample's volume. How did we do that?

measured volume using water displacement method

The lithosphere and asthenosphere are interior layers of the Earth primarily defined on the basis of their

mechanical strength (strong vs. weak)

Sheet Silicates

mineral group called biotites (mica) and muscovites

According to Hutton's Principle of Uniformitarianism:

modern geologic processes occur in much the same manner as they did in the past

Outer Core

molten/liquid, metallic, S-Waves disappear

Stratovolcano

most explosive, concave slopes, Plinian eruption style (extremely violent), pyroclastic flows, form at subduction zones Example: Mt. Fuji

Laccolith

mushroom shaped

Shield Volcanoes

non-explosive, but largest in size Example: Hawaii

Pillow Basalts

only form underwater, lava enters water passively as bulbous bodies of quenched (cooled quickly) forming a glassy skin

An element is defined by the number of _______ in its nucleus

protons

The 1997 eruption of Soufriere Hills, Montserrat of the Carribbean produced a 10km ash cloud and a dense cloud of hot gas, ash & volcanic debris called a ___________.

pyroclastic flow

What hazard? 1902 Mt. Pelee Caribeean, kills 29,000.

pyroclastic flow

What hazard? 79 AD Mt. Vesuvius, Italy kills 1500

pyroclastic flow

Which of the following is a primary(main) hazard of stratovolcanoes?

pyroclastic flows

According to Bowen's Reaction Series, which mineral crystallizes last and is most stable at Earth's surface temperatures & pressures?

quartz

Using sun, shadows & simple math, Greek scientist Eratosthenes, calculated the Earth's_____________.

radius

Which igneous rock was quenched (cooled quickly) & contains the highest amount of silica?

rhyolite

Which is the largest (size) type of volcano?

shield

Crust

silica rich, thinnest, least dense

Mantle

silica-poor, thickest layer

To which of the following groups do most minerals in the Earth's crust belong?

silicates

These miners are looking at crystals of the mineral Gypsum. The most unique identifying characteristic of Gypsum is

softer than a human fingernail

Which group of meteorites is most similar in chemical composition to the mantle?

stony-iron meteorites

A steep, concave-sided cone-shaped volcano is called a __________ volcano.

strato

Souffriere Hills, Montserrat in the Carribbean is a ___________ volcano.

subduction zone

The Cascades volcanic mountain chain of the Pacific Northwest (Washington state, Oregon, northern California) are produced by

subduction zones

The common mineral halite has a distinctive

taste

Kilauea lava flows are typically low viscosity flows.

true

What hazard? 1986 Lake Nyos, Cameroon, W. Aftica, kills 1700

volcanic gasses

What are the four hazards for volcanic eruptions?

volcanic gasses, lahars, pyroclastic flows, lava flows

Caldera

walled basin formed when magma chamber empties after largest eruption & supported roof of chamber collapses under its own weight (Crater, Lake Oregon)

Mud Pot

where hot acidic water start to break down rocks