Geology of National Parks Final

What is a volcano?

A weak spot in the crust where molten material, or magma, comes to the surface.

How are magma and lava the same?

essentially the same substance - molten rock

How are magma and lava different?

Magma is molten rock INSIDE the earth's surface. Lava is what we call it once it is above the surface.

What are the 4 types of volcanoes?

super volcanoes, shield, explosive (strato/composite), cinder

What is a Super volcano?

(highly viscous) an unusually large volcano having the potential to produce an eruption with major effects on the global climate and ecosystem.

What is a shield volcano?

(low viscosity) a wide, gently sloping mountain made of layers of lava and formed by quiet eruptions

What is a composite volcano?

(very high viscosity) A tall, cone-shaped mountain in which layers of lava alternate with layers of ash and other volcanic materials

What is a cinder volcano?

(low viscosity) A steep, cone-shaped hill or small mountain made of volcanic ash, cinders, and bombs piled up around a volcano's opening

What is an igneous rock?

A type of rock formed from the cooling and solidification of magma or lava.

What is Aphanitic?

A texture of igneous rocks characterized by fine-grained crystals that are too small to be seen with the naked eye, indicating rapid cooling of lava.

What is Phaneritic?

A texture of igneous rocks characterized by coarse-grained crystals that are large enough to be seen with the naked eye, indicating slow cooling of magma.

What is Pyroclastic (ash)?

A type of igneous rock formed from volcanic eruptions that eject ash and other fragments, which then solidify.

What is Vesicular?

A texture of igneous rocks characterized by the presence of vesicles or gas bubbles, formed when lava cools rapidly and gas escapes.

How are the properties of igneous rocks influenced?

by their cooling history, mineral composition, and texture.

What is Granite cooling rate and chemistry?

is an igneous rock that forms from slow-cooling magma beneath the Earth's surface, resulting in a coarse-grained texture and a composition primarily of quartz, feldspar, and mica.

What is Diorite cooling rate and chemistry?

is an igneous rock that forms from the slow cooling of magma, typically found beneath the Earth's surface, resulting in a coarse-grained texture and a composition rich in plagioclase feldspar, with lesser amounts of biotite, hornblende, and quartz.

What is Gabbro cooling rate and chemistry?

is an igneous rock that forms from the slow cooling of magma beneath the Earth's surface, resulting in a coarse-grained texture and a composition primarily of pyroxene and plagioclase feldspar.

What is Rhyolite cooling rate and chemistry?

is an igneous rock that forms from the rapid cooling of lava at the Earth's surface, resulting in a fine-grained texture and a composition primarily of quartz and feldspar.

What is Andesite cooling rate and chemistry?

is an igneous rock that forms from the moderate cooling of magma at or near the Earth's surface, resulting in a fine- to medium-grained texture and a composition that typically includes plagioclase feldspar, along with biotite and hornblende.

What is Basalt cooling rate and chemistry?

is an igneous rock that forms from the rapid cooling of lava at the Earth's surface, resulting in a fine-grained texture and a composition primarily of pyroxene and plagioclase feldspar.

What is Pumice cooling rate and chemistry?

is an igneous rock formed from the rapid cooling and depressurization of volcanic lava, resulting in a light, porous texture and a composition rich in silica, typically containing minerals like quartz and feldspar.

What is Scoria cooling rate and chemistry?

is an igneous rock that forms from the rapid cooling of lava, resulting in a vesicular texture and a composition rich in iron and magnesium, primarily consisting of pyroxene and plagioclase feldspar.

What is Vesicular Basalt cooling rate and chemistry?

is an igneous rock that forms from the rapid cooling of lava with gas bubbles, resulting in a porous texture and a composition similar to basalt, rich in pyroxene and plagioclase feldspar.

What is Obsidian cooling rate and chemistry?

is a naturally occurring glass formed from the rapid cooling of lava, resulting in a smooth, glassy texture and a composition rich in silica, often containing trace amounts of minerals.

Where does the heat come from to power geothermal systems?

comes from the Earth's internal processes, including the decay of radioactive isotopes and residual heat from the planet's formation. This heat is transferred to underground water, creating steam and hot water reservoirs.

How do geysers eurpt?

due to the buildup of pressure from steam in underground water reservoirs. When the pressure exceeds the strength of the surrounding rock, it causes the water to violently erupt to the surface.

How do hot springs erupt?

erupt due to the circulation of groundwater that is heated by geothermal energy. When this water reaches the surface, it creates a pool of hot water, often resulting in steam and bubbling.

Hawaii

Hot spots under thin oceanic crust, Effusive, Shield cone, Basalt/mafic magma – non explosive

Mt. St Helens, Washington

Oceanic crust subduction under Continental crust, explosive, composite cone/strato volcano, Felsic
magma, fluid rich

Crater Lake NP, Oregon

Oceanic crust subduction under Continental crust, explosive, composite cone/strato volcano, Felsic
magma, fluid rich

Lassen Volcanic NP California

Oceanic crust subduction under Continental crust, explosive, composite cone/strato volcano, Felsic
magma, fluid rich

Katmai, Alaska

Oceanic crust subduction under Continental crust, explosive, composite cone/strato volcano, Felsic
magma, fluid rich

El Malpais, New Mexico

Rift – continental – Basaltic
lava flow and cinder cones, scoria

Capulin New Mexico

Rift – continental – Basaltic
lava flow and cinder cones, scoria

Craters of the Moon, Idaho

Rift – continental – Basaltic
lava flow and cinder cones, scoria

Devils Tower, Wyoming,

Intrusive/Plutonic Igneous rocks,
Basaltic to Granitic

Mt. Rushmore, ND.

Intrusive/Plutonic Igneous rocks,
Basaltic to Granitic

Devils Postpile CA

Intrusive/Plutonic Igneous rocks,
Basaltic to Granitic

Yellowstone NP, Wyoming

super Volcano & geothermal activity

Lassen Volcanic NP, CA

Geothermal activity

Hot Creek Gorge, CA,

Geothermal activity

Hot Springs NP, Arkansas

Geothermal activity

How are sedimentary rocks made?

when small pieces of weathered rock, called sediment, are deposited in layers, compacted together, and then cemented by minerals, essentially "gluing" the particles together to create a solid rock; this process occurs on the Earth's surface through weathering, erosion, transportation, and deposition of the sediment particles.

What is sediment?

deposits of pre-existing rocks or pieces of once-living organisms that accumulate on the Earth's surface.

Where does weathering occur?

anywhere on the Earth's surface where rocks and minerals are exposed to the elements like air, water, and living organisms, including mountains, deserts, coastlines, and even urban environments

What is mechanical weathering?

is the process by which rocks, minerals, and soils break down into smaller pieces without changing their chemical composition.

What is chemical weathering?

is an erosional process in which rocks and other materials are broken down by chemical reactions

What is the relationship between weathering and particle size?

Weathering generally leads to a decrease in particle size, meaning that as rocks weather, they break down into smaller and smaller fragments, with smaller particles having a larger surface area exposed to further weathering processes, thus accelerating the rate of weathering; essentially, the smaller the particle size, the faster the weathering rate due to increased surface area exposure.

What is a fossil?

the preserved remains of an organism that lived in the past, or evidence of that organism's life

What can fossils tell us about the past?

information about ancient ecosystems, climates, the evolution of species, and how organisms interacted with each other

What are Paleo environments?

is an ancient environment that has been preserved in the Earth's natural archives, such as rocks and marine sediments

How are Paleo environments formed?

through the natural preservation of past environmental conditions within the geological record, primarily through the deposition of sediments that contain fossils, minerals, and other physical characteristics which can be analyzed to reconstruct the climate, geography, and life forms present at a specific point in Earth's history

Why is there bias in the fossil record?

not all organisms have an equal chance of becoming fossilized

What are coastlines/ seashores?

are dynamic and changeable rivers of sand. Coral reef preservation protects
coastlines

What is a desert?

any large, extremely dry area of land with sparse vegetation

How much of the Earth is covered in deserts?

33%

Where do deserts occur?

most deserts, such as the Sahara of North Africa and the deserts of the southwestern U.S., Mexico, and Australia

How does water sculpt the desert environment?

creating unique erosional and depositional landforms like canyons, mesas, buttes, and alluvial fans through the process of surface runoff

How wind produces features in a desert?

through the process of erosion, where it picks up loose sand and sediment, carrying it to new locations where it is deposited

How much of the Earth’s surface is currently covered in glaciers?

10%

What portions of the hydrologic cycles do glaciers represent?

storage portion

How does glacial ice form?

when snow accumulates in a cold region over many years, progressively compressing and recrystallizing into denser layers called firn, which eventually become a solid mass of ice under the weight of the accumulating snow, with the process primarily driven by pressure and time; as the ice builds up, it begins to flow downhill due to gravity, forming a glacier

How do glaciers erode? what features do they create?

plucking (where pieces of rock are pulled out from the bedrock by freezing water) and abrasion (where the rock debris carried by the glacier grinds against the underlying rock surface)

Kenai Fjords NP, Alaska

Glacial

Glacier NP, Montana

Glacial

Great Sand Dunes, Colorado

sediment

Arches, Zion, Bryce Utah

sediment turned into rock and now eroded

Grand Canyon, Arizona

sediment turned into rock and now eroded

Guadalupe Texas

Biological/Chemical - fossilized coral reef

Great Salt Lake state park, Utah

Evaporite/Precipitate

White Sands, NM

Evaporite/Precipitate

Petrified Forest NP, Arizona

Evaporite/Precipitate

Florissant Fossil Beds, NM Colorado

Evaporite/Precipitate

Dinosaur NM, Colorado

Evaporite/Precipitate

Cape Hatteras, NC

Seashores and coral reefs

Biscayne NP, Florida

Seashores and coral reefs

Great Basin

Deserts

Sonoran Desert

Deserts

Joshua Tree NP

Deserts

How are metaphoric rocks formed?

when existing rocks, like sedimentary or igneous rocks, are subjected to intense heat and pressure deep within the Earth's crust, causing them to recrystallize and change their mineral composition and texture, essentially transforming into a new type of rock

Smokey Mts

Metaphoric rock

Shanandoah NPs

Metaphoric rock

What is the rock cycle?

a geological process that describes how the three main types of rocks - igneous, sedimentary, and metamorphic - continuously transform from one type to another through processes like melting, cooling, weathering, erosion, and compaction, driven by Earth's internal heat and surface conditions

(In the rock cycle): What is weathering and erosion?

Breaking down existing rocks into smaller particles.

(In the rock cycle): What is Transportation?

Movement of eroded particles by wind or water

(In the rock cycle): What is Deposition?

Sediment settling and accumulating in new locations

(In the rock cycle): What is Lithification?

Compaction and cementation of sediments into sedimentary rocks. 

(In the rock cycle) What is Melting?

Rock transforming into magma due to high temperature

(In the rock cycle) What is Cooling and crystallization?

Magma solidifying to form igneous rocks

(In the rock cycle): What is Metamorphism?

Transformation of existing rocks due to heat and pressure.

What is a Convergent boundary?

a place where two or more tectonic plates meet and collide

What plate causes mountain ranges, volcanoes, and earthquakes?

Convergent Boundaries

What is a Transform Fault?

a place where two tectonic plates slide past each other horizontally, creating a zone of shearing that deforms the crust

What is Divergent Boundary?

a geological feature where two tectonic plates are moving apart from each other, causing new crust to be formed as magma rises from the Earth's mantle to fill the gap between the separating plate