Test 1-Geology

Sedimentary Processes Compaction/lithification

A dump truck dumps a load of gravel on your lawn. The dirt below it becomes more consolidated.

Elements likely to bond

1. Magnesium and oxygen (Mg and O) 2. Potassium and Chlorine (K and Cl) 3. Sodium and Chlorine (Na and Cl) 4. Potassium and Bromine (K and Br)

Elements unlikely to bond

1. Oxygen and Krypton (O and Kr) 2. Hydrogen and Neon (H and Ne) 3. Lithium and Argon (Li and Ar)

rock unit #2 characteristics (pt 2)

1. Sedimentary rock 2. Mudstone 3. Deposited in a terrestrial environment

Sedimentary Processes Sediment Erosion/ transport

1. The dirt going down the drain after you give your dog a bath and drain the tub 2. Dirt being blown

Sedimentary Processes Weathering of rock

1. Tree roots extending into a rock layer and breaking it down 2. Ice expanding in a crack in the road creating a pothole

rock unit #2 characteristics

1. Weathers into small irregular shapes 2. Appears to have many thin layers 3. Red and white in color 4. Sediments too small to see

How many cleavage directions does this mineral specimen display?

3

Rank these locations based on rates of weathering as a function of climate.

Fastest: A,C,B

Rank the rocks from fastest weathering to slowest weathering.

Fastest: Peridotite Gabbro Diorite Granite

Study these images and select the statement that describes the correct comparison of the porosity and permeability of these two rocks.

Rock A has a lower porosity and a lower permeability than Rock B.

What form of physical weathering is shown in this image?

Root wedging

What is salt weathering?

The formation of minerals in rock cracks during the evaporation of salty water, forcing rock apart.

As a geologist, you always want to first locate your field site on a map. It helps other geologists to locate the field site for future studies and helps you look for relationships with data from nearby field sites. Determine where you are (your field site) in the world. Choose the map that best locates your field site.

The outcrop is located in the northeast corner of Minnesota.

Choose the cross-section sketch that best represents the rock units you observe at this scale.

You have come to see that there are two main rock units stacked on one another

What is foliation?

banding in metamorphic rocks that results from the reorientation of minerals

Coquina

biochemical rock comprising shells made from calcite

Granite

coarse-grained rock containing plagioclase, quartz, potassium feldspar, and hornblende

Breccia

coarse-grained rock with large angular particles cemented with mud

Granite

course-grained, felsic composition

Gabbro

course-grained, mafic composition

Rhyolite

fine-grained, felsic composition

Basalt

fine-grained, mafic composition

Gneiss

foliated rock exhibiting banding

How will foliation in continental metamorphic rocks formed during subduction be oriented?

perpendicular to the direction of plate movement

Tuff

pyroclastic rock with particles less than 4 mm in diameter

Chemical weathering would predominate.

1. A warm wet environment with above average yearly rainfall and several stormy seasons each year. 2. A hot environment with many short but intense rainstorms. 3. A hot humid climate with heavy precipitation that occurs all year.

rock unit #1 characteristics

1. Appears to be massive (few, thick layers) 2. Black and grey in color 3. Weathers into blocky pieces 4. Crystals too small to see

Sedimentary Processes Deposition of sediment

1. Dust collecting on furniture

rock unit #1 characteristics (pt 2)

1. Igneous rock 2. Basalt 3. Formed by lave cooling and crystallizing on the surface 4. Rock with a low-silica content

Mechanical weathering would predominate.

1. A cold dry environment experiencing uplift, in which material is being removed by erosion from an underlying pluton/intrusive igneous rock. 2. A cold wet environment at high elevation, in which freezing and thawing is common.

Geological Events: Rank from oldest to most recent events

Oldest: 1. Formation of Vishnu Schist 2. Deposition of sedimentary layers found above the Vishnu Schist 3. Carving of the canyon by the Colorado River

Process from oldest to youngest

Oldest: 1. Deposition of sediments on a floodplain 2. Compaction and cementation of sediments (lithification) 3. A nearby volcano erupts, creating a lava flow 4. Lave flow erodes sedimentary layers and then cools on the top of them

Choose the most accurate representation of the outcrop's orientation given your vantage point (as viewed using the Gigapan in relation to the outcrop).

The photographer/image is looking towards the west. In other words, the outcrop faces east at the lake behind the photographer.

Why does quartzite not exhibit foliated texture?

There are very few or no tabular minerals in quartzite.

Sedimentary Rocks in the LandscapePart complete

Top Left: Shale Bottom Left: Water Retention Pond Top Right: Sandstone Bottom Left: Talus

Obsidian

glassy texture

What is a mantle plume?

hot mantle rock rising from deep within the Earth

Diorite

intermediate composition

Marble

nonfoliated rock with large calcite crystals

Slowest chemical weathering to fastest

slowest: 1. Granite, with very few or no cracks. 2. Granite, with abundant cracks. 3. Basalt, with very few to no cracks. 4. Basalt, with abundant vesicles (holes).

Peridotite

ultramafic composition

Pumice

vesicular texture