Geology

List three detrimental effects of soil erosion, other than the loss of top soil.

Desertification, water pollution, and air pollution in the form of dust.

What is "regolith"? What is "solum"? How do they relate to each other?

Regolith is the layer of unconsolidated rocky material covering bedrock. The solum (plural, sola) in soil science consists of the surface and subsoil layers that have undergone the same soil forming conditions. Solum is the upper portion of the regolith that has been altered through biochemical and physical processes.

9. What are the two components that define mass wasting events?

(a) nature of slope material (b) amount of water in the slope material (c) steepness of the slope.

The downslope movement of rock, regolith and soil under the direct influence of gravity

Mass Wasting:

The physical disintegration of rock, resulting in smaller fragments

Mechanical weathering:

If two identical rocks were weathered, one mechanically and one chemically, how would the results differ?

The smaller rocks yielded by the mechanically weathered rock would be identical to the original rock while the products of the chemically weathered rock would yield dissimilar, new substances that are the decomposed original rock.

the steepest angle at which loose material remains stationary without sliding down slope

Angle of repose:

Heat speeds up a chemical reaction. Why then does chemical weathering proceed slowly in a hot desert?

Chemical weathering occurs through the processes of solution, hydration, carbonation and oxidation & reduction. Whichever process is followed there is a slight requiremnet of water for the weathering to occur. Because in chemical weathering, minerals in rocks disslove in either water and/or carbonic acid (weak acid, formed when water absorbs carbon dioxide). As a desert has less amount of moisture content, so it is slow in desert.

the process by which the internal structure of a mineral is altered by the removal and/or addition of elements

Chemical weathering:

The slow downhill movement of soil and regolith

Creep:

What are the 6 "horizons" in a well-developed soil?

O Horizon - The top, organic layer of soil, made up mostly of leaf litter and humus (decomposed organic matter). A Horizon - The layer called topsoil; it is found below the O horizon and above the E horizon. Seeds germinate and plant roots grow in this dark-colored layer. It is made up of humus (decomposed organic matter) mixed with mineral particles. E Horizon - This eluviation (leaching) layer is light in color; this layer is beneath the A Horizon and above the B Horizon. It is made up mostly of sand and silt, having lost most of its minerals and clay as water drips through the soil (in the process of eluviation). Steven Wilder: chemical weathering would impact basalt more because its minerals are less stable at surface temp and pressure B Horizon - Also called the subsoil - this layer is beneath the E Horizon and above the C Horizon. It contains clay and mineral deposits (like iron, aluminum oxides, and calcium carbonate) that it receives from layers above it when mineralized water drips from the soil above. C Horizon - Also called regolith: the layer beneath the B Horizon and above the R Horizon. It consists of slightly broken-up bedrock. Plant roots do not penetrate into this layer; very little organic material is found in this layer. R Horizon - The unweathered rock (bedrock) layer that is beneath all the other layers.

The downward slipping of a mass of rock or unsoldered material moving as a unit along a curved surface

Slump:

a layer of soil that has distinct characteristics produced by chemical weathering and other soil-forming processes

Soil horizon:

a vertical section through a soil, showing its succession of horizons and the under lying parent material

Soil profile:

a combination of mineral and organic matter, water, and air; the portion of the regolith that supports plant growth

Soil:

an accumulation of rock debris at the base of a cliff

Talus slope:

The disintegration and decomposition of rock at or near the surface of Earth

Weathering:

How does mechanical weathering add to the effectiveness of chemical weathering?

breaking down rocks int smaller pieces increases the surface area for chemical attraction

Granite and basalt are exposed at the surface in a hot wet region. Which type of weathering will predominate? Which of the rocks will weather most rapidly and why?

chemical weathering would impact basalt more because its minerals are less stable at surface temp and pressure

What might cause similar soils to develop from different parent materials, or different soils to form from similar parent materials?

climate, slope, time, vegetation