Geology 101

Which of the following is a temperature associated with metamorphism?

400 degrees celcius

What is the difference between a dike and a sill?

A dike intrudes across sedimentary layers, and a sill intrudes between sedimentary layers.

What is the difference between aa lava and pahoehoe lava?

Aa lava has a prickly texture; pahoehoe has a smooth, ropy texture.

Which one of the following statements is NOT true about andesite and basalt?

Basaltic lava is thicker than andesitic lava.

How do calderas form?

Calderas form when the summit of a volcano collapses.

What is one way that cinder cones differ from composite and shield volcanoes?

Cinder cones are smaller than composite and shield volcanoes.

Which of the following best describe how flood basalts form?

Flood basalts form as a result of an eruption above a mantle plume.

Which materials in Hawaii's lava help to keep it fluid for longer at the surface (as opposed to cooling and solidifying quickly), thus allowing extensive lava flows to develop?

Iron and Magnesium

Below is an image of the island of Hawaii. Kilauea, located on the Big Island, is a currently erupting volcano. Which of the following islands is the oldest?

Kaua'i

Hot spots are best described as which of the following?

Localized areas of volcanic activity not associated with plate boundaries.

Which of the following scenarios best describes how the Hawaiian Islands formed in the Pacific Ocean?

Magma generated from a hot spot burned through the overlying plate to create volcanoes.

Which of Hawaii's five volcanoes are still considered to be active?

Mauna Loa and Kilauea

Which of the following has the single most immediate effect on lava's ability to solidify?

Temperature

The volcanic islands in the above figure were created as the tectonic plate passed over a hot spot in the mantle. Based on the ages of the volcanic islands, in what direction was the tectonic plate moving toward?

Toward the West

Why are volcanic rocks often exposed at Earth's surface as hills, ridges, and mountains surrounded by areas of lower elevation?

Why are volcanic rocks often exposed at Earth's surface as hills, ridges, and mountains surrounded by areas of lower elevation?

What is a magma chamber called after the conduit has solidified and been exposed by erosion?

a batholith

What is piled up along the cone of SP Crater that causes it to be so steep?

cinders

What kind of metamorphic texture results in the segregation of light and dark mineral bands?

gneissic texture

What is a mantle plume?

hot mantle rock rising from deep within the Earth

What lies underneath volcanic features at Earth's surface?

magma chambers and volcanic conduits

From where do scientists think that mantle plumes originate?

shallow locations within the mantle;the outer core-mantle boundary

What causes vesicles to form in lava?

trapped gas bubbles

What is a volcanic conduit called after the conduit has solidified and been exposed by erosion?

volcanic neck

What geologic process is related to caldera formation?

volcanism