ESS 101 Midterm 2

The lava composition of Mt. St. Helens is _____________ and tends to be more __________ than lavas erupted from Mt. Rainier.

1. Dacite 2. Silica-rich

Conditions of karst landscape of Southern China

1. Limestone or carbonate 2. Slow uplift 3. Very humid climate 4. Not glaciated

Soil profiles can form_______________.

-In residual bedrock -In unconsolidated sediment

What is/are the main component(s) that make up acid rain derived from burning fossil fuels?

-Nitrogen oxides -Sulfure oxides

Which of the following depositional setting do not generally result in cross beds?

-Wind-blown sand dunes -Migrating stream channels

As soils age the soil profile becomes

-Thicker -Redder -More clay rich

What is correct about volcanic ash layers?

-Volcanic ash layers get thicker as you get closer to the volcanic source -Volcanic ash layers get coarser-grained as you get closer to the volcanic source

Most acid rain that fell in the United States in 2000 had a pH of ______.

4.3

Concrete contributes _____% of the annual anthropogenic global CO2 production.

5

Roman roads have used concrete for their construction since 312 B.C. Roman roads were typically _______ thick from their base to surface.

5 feet.

A study by Wood and Soulard (2009) noted that ____________ residents lived in the area inundated by the Mt. Rainier Electron lahar 500 years ago.

78,000.

A tabular-shaped pluton that is deposited parallel to the sedimentary strata is _________________.

A sill.

Besides oxidation reactions which of the following are examples of chemical weathering?

Dissolution of limestone, hydrolysis reactions of kaolinite.

Which soil horizon forms in acidic boreal forest soils and contains no organic matter (bleached horizon)?

E horizon.

Which of the following is not a process that leads to the lithification of sedimentary rock?

Flocculation of sediment.

Which of the following is not a soil forming process?

Hydration of void spaces between soil particles following a precipitation event.

What is special about kaolinite clay?

It does not have shrink-swell properties.

Why is muscovite the most dominant mineral comprising most beach sand?

It is not, quartz is. Quartz is more resistant to chemical weathering than other silicate minerals.

In the mineral lab, the main diagnostic criteria for identifying biotite mica was _____________.

Its cleavage into dark, flexible sheets.

Which of the following statements about joints are not important in enhancing weathering in rock?

Joints increase tension in the rock causing weathering reaction rates to increase.

When erupted material mixes with river water or melts snow and ice resulting in a volcanic mudflow, this is known as ___________.

Lahar.

In the plate tectonics lab we observed that oceanic crust comprising the Juan de Fuca plate was being created at the spreading ridge at a rate ____________________ the rate of its subduction beneath the North American Plate.

Less than.

What is the most important rock or mineral in concrete production?

Limestone.

More than 60 Global Positioning System (GPS) stations track the position of Cascade volcano monitoring stations in three dimensions to within a small fraction of an inch. This GPS information allows CVO scientists to quickly identify any unusual movements due to _________________________.

Magma.

Chert generally precipitates in deep ocean water because ________.

None of the above answers are correct as chert typically precipitates in deep ocean water.

What structure in a basalt would indicate that it was erupted under water?

Pillow basalts.

The rock shown in the image below has a ___________ texture.

Porphyritic (2 stages of cooling).

Volcanic lahars are more problematic for communities_____________.

River valleys that drain volcanoes.

After the great fire of 1889, many builders in Seattle began to rely on stone rather than wood for construction. The most common local rock that was used for building construction is _________________.

Sandstone.

Which mineral crystallized first?

Small black mineral included within the white material.

In the "History of Concrete" the oldest form of concrete discovered at 6500 B.C. was used in _______________.

Syria

Why does the Yellowstone hotspot volcanism produce more explosive volcanic eruptions than the Hawaiian hotspot volcanism?

Upwelling basaltic magma partially melts the overlying continental crust producing viscous rhyolitic lava.

Which of the following building/structures is not considered a "Top 5" endangered heritage sites due to acid rain destruction?

Washington Monument, U.S.A.

Frost wedging occurs in rock because:

Water expands when it freezes to form ice.