forms most of the earth's crust under the continents
granite
the weathering away of the earth's topsoil
erosion
one revolution of the earth takes
365 1/4 days
largest ocean
Pacific
decayed material in soil
humus
made from layers of sand
sandstone
using natural resources wisely
conservation
one rotation of the earth takes
1 day
smallest continent
Australia
scientists who study the earth
geologists
used to make the Washington Monument
marble
rivers of ice that move very slowly
glaciers
divides the earth in half
equator
coldest and smallest ocean
arctic
upper layer of soil
topsoil
made from seashells
limestone
a deposit of sand and soil at the mouth of some rivers
delta
each half of the earth is called
hemisphere
contains the countries of Eqypt and Ethiopia
Africa
hot liquid rock
magma
pebbles or cobbles cemented together
conglomerate
matter that settles to the bottom or sides of a body of water
sediment
imaginary line that runs through the earth
axis
the number of continents
7
best topsoil is a mixture of
sand, silt, clay, and humus