Thursday, October 14, 2010

CHAPT 8

MOUNTAIN

A area of high ground.
usually 6oom and above,

eg. mount everest, mount himalayas

HILL

Area of high ground
rounded in shapes
has gentle slopes

VALLEY

Low area of land
Between hills or mountains

PLAINS

Broad, flat and low area of land.

PLATEAU

Raised area of land
Flat broad top
Has steep slopes.

MANTLE

2900 KM
80% Of earth's volume
2000 degrees c.
top layer is semi-molten/liquid

CORE

5000 degrees c.
inner part of it is solid
because of the great pressure and weight exerted on the core by the outer layer of earth/

CRUST

6 to 7 km thick
solid
made up of plates that float on semi-molten/liquid(magma)

INTERNAL FORCES THAT CREAT LANDFORMS

The earth's crust is always moving
movement of the plates on the semi-molten/liquid is called crustal movement
when plates move, the might slide past, pull apart from or push towards each other.
mountains and volcanoes are created by processes occuring within the earth on the earth's surface. (FOLDING AND VULCANICITY)

FOLDING

two plates collide and and some of the layers of rock that makes up the earth's crust will buckle and form folds.
the amount of foldings can be so little that it is hardly noticeable or it can be so large that a mountain is formed as a result.

eg. himalayas in nepal, mount everest, alps in europe, mount kinabalu(sp?)

VULCANICITY

the temperature below the earth's crust is so hot that it causes part of the mantle to melt and molten mantle is called magma. this magma pushes its way through cracks which are found on plate boundaries
the process whereby magma and other materials reach earth's surface is called vulcanicity. outpouring if lava is called eruption happens due to releaso of bulit up pressure of gases below earth's surface.

VOLCANOES

consists of vent, pipe, crater and cone

VENT

opening on earth's surface.

PIPE

channel that allows the magma to rise up to the top of the volcano during eruption.

CRATER

bowl shaped opening where volcanic materials like ash and lava are released.

CONE

shape of the volcano
built up by ash and lavaa released from a number of eruptions


Wednesday, October 13, 2010

CHAPT 3

PHYSICAL ENVIROMENT

It consists of physical enviroment(think of the word"nature")
Features that occur naturally on the Earth.
Features that exists in nature but cannot be created by men.

eg. mountains, hills, lakes and rivers

HUMAN ENVIROMENT

It is formed when the Physical Enviroment id changed as a result of human activity.

eg. houses are built on a piece of land that used to be a forest.

MAPS

Are pictures or graphical representations
Represents all or part of the Earth's surface and feaures.
Shows top view only.

eg. topographical map

USES OF MAPS

Used to prepare before going for war
Used to be a source of information
Help to find our way to places of interest
Records changes over time

BASIC ELEMENTS OF A MAP

TITLE

states area shown on a map

GRIDLINES

series of numbered vertical and horizontal lines drawn on a map

CONTOURS

imaginary lines, joining places on a map that are of a same height

NAME OF FEATURES

certain features

eg. buildings to help to identify & locate easily.

NORTH ARROW

shows where North, East, South, West is

SCALE

shows size of map as compared to the actual size of the area that the map represents.

LEGEND

lists all the symbols used in the map/explains what it represents too.

SYMBOLS

represents different physical or human features found on the surface of the Earth.

SCALE

shows relationship between the lenght on the map and the actual distance.

LINEAR SCALE

line divided into units and sub units

measure distance easily and quickly

STATEMENT

eg. 1 cm equals 1km

SYMBOLS

show physical and human features in a map


---END---