Question 1
READING PASSAGE
Reading passage for questions 87 to 91
The earth's crust averages 16 miles thick and rests on what is called the mantle. This layer, about 75 miles thick, is believed to be of a semi-viscous or plastic nature rather than solid. Thus both continental and oceanic areas could be said to float on the mantle, with continental areas pushing deeper into the mantle than do oceanic areas where the crust is thinner.
Constant erosion moves dirt and rock into ocean areas where they settle. These areas gradually sink deeper into the mantle, eventually creating pressure that thrust new land up from surrounding areas. Mountains formed by this process are made of sedimentary rock and are called folded or domes
Earthquakes occur where the crust shifts or creaks apart sharply under pressure; the resulting breaks or fissures are called faults. Mountains created by these faults are called fault blocks. In weak spots on the earth's crust-generally near sea coasts-gases and molten rock under tremendous pressure break through to form conical shaped mountains. These we know as volcanoes
No sooner are new mountains and flatlands created by pressure than water, ice and wind begin to wear them away thus creating new valleys, river courses and coastlines.
Reading passage for questions 87 to 91
The earth's crust averages 16 miles thick and rests on what is called the mantle. This layer, about 75 miles thick, is believed to be of a semi-viscous or plastic nature rather than solid. Thus both continental and oceanic areas could be said to float on the mantle, with continental areas pushing deeper into the mantle than do oceanic areas where the crust is thinner.
Constant erosion moves dirt and rock into ocean areas where they settle. These areas gradually sink deeper into the mantle, eventually creating pressure that thrust new land up from surrounding areas. Mountains formed by this process are made of sedimentary rock and are called folded or domes
Earthquakes occur where the crust shifts or creaks apart sharply under pressure; the resulting breaks or fissures are called faults. Mountains created by these faults are called fault blocks. In weak spots on the earth's crust-generally near sea coasts-gases and molten rock under tremendous pressure break through to form conical shaped mountains. These we know as volcanoes
No sooner are new mountains and flatlands created by pressure than water, ice and wind begin to wear them away thus creating new valleys, river courses and coastlines.
The first paragraph is mainly about the earth's
Objective