Ground water

Groundwaterisfoundalmosteverywherebelowtheearthssurfacemostoriginatesfromrainandsnowbutsmallquantitiescomefromwatertrappedinsedimentsduringtheirdepositionconnatewaterorfromigneousmagmasjuvenilewater.

Exercise 3. Read the following text and fill in the gaps with the word given below and then translate it into Russian:

Porosity

Septarian nodule is formed from 1 … deposited by groundwater in claylike rocks. Groundwater is an important 2 … in both deposition and erosion of surface rocks. It can dissolve original cementing materials and deposit new ones. For example, it produces 3 … and caverns by solution in carbonate rocks.

Porosity, the percentage of pore space to 4 … volume of a rock, depends upon the grain 5 …, shape, packing, and cement of rock particles. The permeability of a 6 …, or its capacity to transmit or yield water, depends upon the size of pores, rather than their total volume. Pores 7 … than 1/20 of a millimeter will not allow water to flow through them.

Well-sorted sand (enlarged view) with 8 … porosity due to sorting, which has removed fine-grained particles.

Poorly sorted 9 … has lower porosity than well-sorted sand, because the pore spaces are filled by fine particles.

Limestones generally hold 10 … in enlarged joints formed by solution; they lack the “pore space” of sandstones.

Missed words:

1. – high

2. – sand

3. – size

4. – water

5. – caves

6. – rock

7. – total

8. – agent

9. – minerals

10. – smaller

Exercise 4. Read and translate the following expressions:

the zone of aeration, arid regions, the zone of saturation, water-bearing rock, rarely found, level of the water table, after a dry season, deep enough to penetrate the water, all year round, a saucer of impervious rock

Exercise 5. Read the text “The Water Table” and find in it the words with the following meanings to fill in the crossword below:

				G
				R
				O
				U
				N
				D
				W
				A
				T
				E
				R

1. administrative division of a country; an area considered as a unit with no definite boundaries

2. hard mineral substance that makes up a part of the earth’s crust; large rugged mass of stone

3. arrangement of people or things acting as a unit; structure or shape

4. a top of an object

5. to find a way into or through

6. lacking moisture; having little or no rainfall

7. at a position lower than

8. a water-bearing layer

9. distance downwards

10. one of four divisions of a year

11. desert climate with not enough rainfall to support plants