5 Fill in the gaps

warps	heat	anticlines
wavelike	crust	chains
basin	temperature	dome

Near the surface of the ____________ (1), at atmospheric temperatures and pressures, rocks tend to break when subjected to great stresses such as earthquakes. However, deeper into the crust, _____________ (2) rising from the mantle raises the rocks' temperature, and the pressure of overlying rocks compresses them. At these higher __________ (3) and pressures, the rocks become somewhat flexible. Instead of breaking, they tend to warp or fold when stressed. _______________ (4) occur when broad areas of the crust rise or drop without frac­turing. The rock strata in these areas appear to be horizontal but, on closer inspection, are actually slightly tilted, or dipping.

Rock strata that have crumpled and buckled into ______________(5) structures are called folds. Folds are the most common structures in mountain ________________ (6), ranging in size from wrinkles of less than an inch to great arches and troughs many miles across. The upwarps or arches are called _______________ (7); the downwarps or troughs are synclines. Geologists further divide anticlines and synclines according to how the folds tilt. A short anticline with its crest plunging downward in all direc­tions from a high point is called a ___________________ (8). Many domes are almost perfectly circular. Some of them have a core of one type of rock that has pushed up into the surrounding rock and lifted it, such as the salt domes along the U.S. Gulf Coast. A syncline that dips down toward a common center is called a _______________ (9). Anticlines and synclines are important to petroleum geologists because they often contain petroleum.

Grammar section noun

A noun is a word expressing substance in the widest sense of the word. In the concept of substance we include not only names of living beings (e.g. ) used to name a person, animal, place, thing, and abstract idea. The highlighted words in the following sentences are all nouns:

Geologists try to answer such questions as how old the earth is.

Erosion, movement of crustal plates, and movement of molten rock continuously create new types of rock from the old.

A noun can function in a sentence as a subject, a direct object, an indirect object, a subject complement, an object complement, an appositive, an adjective or an adverb.

Morphological composition of nouns

According to the morphological composition we distinguish simple, derivative and compound nouns.

Simple nouns are nouns which have neither prefixes nor suffixes, for instance, dome, trap, salt, oil, rock, shale.

Derivative nouns are nouns which have derivaqtive elements (prefixes or suffixes or both). They are as follows:

-er: layer -hood: childhood

-ist: geologist -dom: freedom, wisdom

-ess: authoress -ship: friendship, relationship

-ness: effectiveness -ment: sediment, movement

-ism: conservatism -ance: appearance

-ence: eminence -ty: difficulty

-ity: porosity, permeability -tion: formation, migration