Science self test 1094

Cirque

A ___________ is a bowl-shaped valla that was formed when accumulated snow on the mountainsides was packed into glacial ice slid down the mountain walls.

Terminus

A glacier's __________ is the point where the ice at the end of the glacier begins to melt as fast as the glacier advances.

Subsoil

Below the topsoil layer is the _____________, which extends down to solid rock.

Silt

Loam is the perfect mixture of clay, sand, and (________), and it is one of the most valuable types of soil to farm because it is easy to cultivate.

Pioneers

Mosses and lichens act as ______________ in weathering rocks because they are the first types of organisms to grow in rock crevices.

Ocean

Calving is the process of ice breaking off the glacier into the _____________.

Arêtes

Sharp-spine ridges of rock, called (___________), remained between the valleys after glaciers scraped out the valleys.

Temperature, composition

Physical weathering is the breaking down of rocks by physical processes, such as wind, water, and __________ changes, and chemical weathering is the breaking down of rock by chemical processes that change the _____________ of the rock.

Hydrolysis

During ______________, water causes certain mineral molecules to break down chemically to form different minerals.

Moraines

Moving glaciers sometimes left ridges of till called (_________).

Nitrate

Nitrogen-fixing bacteria on the roots of legumes are able to combine nitrogen and oxygen into (__________) compounds green plants can use as fertilizer.

Organic

As they feed on dead organisms, microorganisms chemically break down _____________ matter into minerals plants need for growth.

Irrigation

Effective use of ____________ involves supplying sufficient amount of water to wash the salt out of the soil, as well as supplying the water requirements of the crops.

Till

Glacial debris no longer moving with the glacier and left on the ground is called (__________).

Gravity

Glaciers move downhill because of the force of ______________.

Humus

_________, the thin, dark layer at the top of the soil profile, is the organic portion of soil that supplies minerals for plant growth.

God

___________ constantly uses situation and circumstances around us to mold us and make us into who He wants us to be.

Creep

____________ is the downhill glacier movement caused by melting or deforming ice.

Expansion

______________ and contraction causes rock to crack, split, and eventually break away from the sides of a mountain.

Exfoliation

______________ is the weathering process that causes sheets of rock to peel away and eventually gives hills and boulders a dome shape.

Tree roots

_______________ can grow into the many cracks and crevices in rock, and as they grow, they split the rock.

Contour, terracing

(_________) plowing is only useful as a soil conservation method on gently sloping land, while ________________ is used to prevent soil erosion on steep hills.

Loess

(___________) is a fine, powdery soil transported by wind or glaciers.

Residual

(___________) soil is formed by weathering of rocks from the local area, and the soil's content depends on the type of rocks being weathered.

Drumlins

(_____________) are long, low rounded hills of till formed by glaciers and are often found in large groups.

Mass soil

Rockslides, landslides, and mudslides are examples of (_______) movements.

Raindrops

Nitrogen compounds and sulfur compounds emitted by factories and automobiles combine with _________________ to form acid rain, which attacks rock structures.

Soil

Weathering is the beginning of _____________ formation.

Clay

In a soil profile, below the layer of humus is the topsoil layer, which contains sand, (_______), and organic matter.

Hydration

During _______________, water molecules combine chemically with mineral molecules to become a new mineral with different properties.

Talus

Both physical and chemical weathering can create a /an (_______), or slope of rock debris, at the base of a mountain.

Erosion

Soil conservation is maintaining soil fertility by protecting the soil from (_______) and other forms of destruction.

Outwash

Meltwater streams carried some dirt away from the terminus of the glacier and deposited it, layer upon layer, in a fan-shaped ___________ plain.

Compost

As a mixture of dead organic material decays, it becomes a dark brown material known as (_________), which is used as fertilizer on lawns and gardens.

Fertility

Soil (___________) is the ability to produce good crops.

Acid

Solution weathering is the process in which an _______________ dissolves minerals in rock and causes the rock to break down.

Kame

When a debris-filled meltwater stream formed a pool or lake beneath a glacier's surface and the glacier receded, and irregular-shaped hill of debris, or (__________), remained.

Mulching

____________ is a method of soil conservation that involves adding humus to the soil and then tilling it into the topsoil to help replace lost minerals.

Oxidation

_________________, a kind of chemical weathering, is the process in which a substance combines chemically with oxygen to form a new substance.