chap 9 (soil)

Question 1

– is the branch of geology that deals with the systematic classification and identification of rocks, rock forming minerals and soils. Also includes study of dust, dirt, safe insulation, ceramics and other such materials both natural and artificial.

Answer 1

Petrography

Question 2

formed from soil particles that were washed, blown, or moved by gravity to the lowlands. Earth, sand, gravel, etc. are deposited by moving water and wind.

Answer 2

Alluvial Soil

Question 3

Its particles may be derived from an almost infinite number of sources, and since the action of water and wind would in few cases be identical over long periods of time in different spots, great variations in composition would be expected.

Answer 3

Alluvial Soil

Question 4

formed from the decomposition of igneous, metamorphic and sedimentary rocks, the decomposed particles moved by gravity. Soil in which some movement and intermingling of parts has occurred would be expected to be less variable.

Answer 4

Colluvial Soil

Question 5

– inactive, not migratory soil.

Answer 5

Sedentary Soil

Question 6

produced by volcanic or intense heat

Answer 6

Igneous Rock

Question 7

– has undergone changed in structure, texture through pressure, heat and chemical reaction. Like limestone into marble.

Answer 7

Metamorphic Rock

Question 8

– Rocks formed by sediments.

Answer 8

Sedimentary rock or sandstone

Question 9

– includes undecomposed rock fragments ranging from stone down through pebbles, sand and silt.

Answer 9

Primary minerals

Question 10

– a form of silica. Crystalline mineral usually colorless and transparent. Also called quartz sand. It originates primarily from igneous rock but much of the soil quartz is contributed directly by metamorphic and sedimentary rock. A common mineral. An almost universal component of soil

Answer 10

Quartz

Question 11

– white reacts with acid with evolution of carbon dioxide. Occurs widely particularly in calcareous soil.

Answer 11

Calcite (Limestone – CaCO)

Question 12

(Silicate of Aluminum or Sodium, or Barium, Calcium, Potassium) – their composition gives rise to clay along with more or less soluble salts of the metals named

Answer 12

Feldspar

Question 13

– white mineral obtained from sedimentary rock. Similar to Limestone.

Answer 13

Dolomite Limestone

Question 14

– a mineral that crystalline in thin, flexible layers, resistant to heat.

Answer 14

Mica

Question 15

– a product of decomposition of primary minerals. Found nearly all soils and is the major constituent of most heavy soil.

Answer 15

Clay minerals

Question 16

It imparts to soil cohesiveness and plasticity and becomes hard and adherent on heating. Pure clay is considered by criminologist to be hydrated aluminum silicate.

Answer 16

Clay Minerals

Question 17

The color of clay soil varies from white through ___,___,___,____,depending on the nature of the admixed impurities.

Answer 17

red, yellow, green, or blue

Question 18

– one of the most variable of all soil constituents and are of peculiar importance in the identification of soil.

Answer 18

Organic constituents

Question 19

is likely to be particularly rich in organic constituents both from growth occurring on the land and from added materials such as manure, peat and cover crops.

Answer 19

Agricultural land