geo

Question 1

list the internal structure of the earth

Answer 1

the crust, the mantle, the outer core and the inner core

Question 2

what is the crust

Answer 2

the crust is the thinnest part of the earth and it is also where we live. it consists of two types of crust which is continental and oceanic crust

Question 3

what is the mantle

Answer 3

the mantle is about 1800 miles thick and it is made up of thick,rocky substances and amounts to about 85% of the total mass of earth and it is also the largest layer of earth

Question 4

what is the outer core

Answer 4

the outer core is made up of lava. this lava is believed to be made up of iron and nickel and extends to a depth of 3000 miles beneath the earths surface

Question 5

what is the inner core

Answer 5

the inner core extends 9000 miles towards the center of the earth. this is a solid ball made of irons and nickel.

Question 6

who made the continental drift theory

Answer 6

german geographer alfred wegnener

Question 7

convergent/ destructive plate boundaries

Answer 7

two crusts, oceanic and continental move towards each other. This forms deep sea trenches, volcanic activities and fold mountains

Question 8

divergent/ constructive plate margin

Answer 8

two plates move away from each other in opposite directions. this forms mid-ocean ridges(the mid-atlantic ridge), shallow earthquakes

Question 9

transform/ transcurrent

Answer 9

plates move horizontally or sideways in opposite directions but parallel to each other. this forms fault lines, rift valleys and violent earthquakes

Question 10

what is weathering

Answer 10

weathering is the process whereby rocks are physically broken down or chemically modified by climatic or biological elements

Question 11

the three types of weathering

Answer 11

physical, biological and chemical

Question 12

physical weathering

Answer 12

the break down of rocks into smaller fragments

Question 13

chemical weathering

Answer 13

decay of rocks caused by alternation of the mineral composition through chemical reactions with water and air

Question 15

what is erosion

Answer 15

the process in which earthen materials are worn away and transported by natural forces such as wind or water

Question 16

what are extrusive volcanic features

Answer 16

extrusive volcanic features are features that can be found on the earth’s surface

Question 17

some extrusive volcanic features are

Answer 17

shield volcanoes
lava plateau
lava domes
cinder/ash cones
caldera
composite cones

Question 18

explain the formation of composite cones

Answer 18

they fom when different types of eruptions deposit different materials around the sides of a volcano. altering eruptions of volcanic ash and lava causes layers to form.

Question 19

explain the formation of shield volcano

Answer 19

shield volcanoes are usually constructed almost entirely of basaltic and/or andesitic lava flows which were very fluid.

Question 20

explain the formation of lava plateau

Answer 20

these are landforms created by volcanic activity. When shield volcanoes erupt, magma flows from the earth’s mantle through fissures in the crust

Question 21

explain the formation of lava domes

Answer 21

lava domes form from the slow extrusion of highly- viscous sillicic lava. These lavas are too thick to spread out into a lava flow.

Question 22

explain the formation of caldera

Answer 22

this forms when magma chambers are partially emptied during large eruption and the land surface subsides

Question 23

explain the formation of cinder/ash

Answer 23

form from ash and magma cinders partly burned, solid pieces of magma, that fall to the ground following a volcanic eruption.

Question 24

what are intrusive volcanic features

Answer 24

this includes batholith, laccolith, sill and dyke

Question 25

what is batholith

Answer 25

this is a very large feature formed when an underground reservoir of molten rock cools and hardens

Question 26

what is laccolith

Answer 26

a mass of igneous rock that is intruded between sedimentary beds and produces a domical bulding of the overlaying strata

Question 27

what is sill

Answer 27

a sill is formed when magma flows horizontally between rock layers, roughly parallel to the surface

Question 28

what is dyke

Answer 28

this is a vertical sheet of rocks formed when magma moving towards the surface cools and hardens