rocks & soil
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ROCKS & SOIL. A PRESENTATION BY CHLOE THORPE. IGNEOUS ROCKS. - PowerPoint PPT PresentationTRANSCRIPT
ROCKS & SOIL
A PRESENTATION BY CHLOE THORPE
CHARACTERISTICS OF ROCKS
COLOR
TEXTURE
HARDNESS
WEIGHT
The Three types of rocks
IGNEOUS ROCKSIgneous rocks are called fire rocks and are formed either underground or above ground. Underground, they are formed when the melted rock, called magma, deep within the earth becomes trapped in small pockets. As these pockets of magma cool slowly underground, the magma becomes igneous rocks. Igneous rocks are also formed when volcanoes erupt, causing the magma to rise above the earth's surface. When magma appears above the earth, it is called lava. Igneous rocks are formed as the lava cools above ground.
EXAMPLES OF IGNEOUS ROCKS
Rhyolite is a light-colored volcanic
rock. It has a high silica content which makes it
very viscous. This prevents gases from
escaping causing rhyolite eruptions to be explosive. Rhyolite has a silica (SiO2) content greater than about 68
percent by weight.
Obsidian is usually black in color though it can also be red or have a greenish tint. It is a dense
volcanic glass, usually composed of rhyolite, rich in
iron and magnesium.Obsidian is
formed when the lava cools so quickly that crystals do
not have time to grow. Obsidian fractures with very sharp edges. It was used by
Stone Age cultures for making knives, arrowheads, and other tools where sharp
edges are important.
Pumice is light and porous. It forms
during explosive eruptions. Pumice is full
of holes caused by expanding volcanic
gases. It is composed of volcanic glass and
minerals, and can form in all types of magma:
basalt, andesite, dacite, and rhyolite.
SEDIMENTARY ROCKS
Sedimentary rock is formed by mineral and other materials sitting in water for an extremely long time. While the minerals and other materials are in the water, they will have various things put pressure on them. After being exposed to these conditions for so long, it forms into sedimentary rock.
EXAMPLES OF SEDIMENTARY ROCK
SANDSTONE is sand
grains cemented together into solid stone.
SHALE is made from silt
particles cemented
together. It is similar to
siltstone but with even finer
grain size,
LIMESTONE is made primarily of
calcium carbonate or calcite. The
most common source of this calcite is the
shells of marine organisms
METAMORPHIC ROCKS
Igneous rocks form from the solidification of lava or magma. If it forms intrusively, or within the earth, the rock will have large crystals. Granite is an example of such a coarse-grained igneous rock. If the rock forms extrusively, or on the earth's surface, it will have fine-grained crystals. Obsidian is an example of a fine-grained igneous rock.
EXAMPLES OF METAMORPHIC
SLATE is a fined
grained metamorphic rock.
MARBLE is a
metamorphic rock that
comes from metamorphosed limestone or dolomite.
QUARTZITE is a coarse-grained metamorphic rock derived
from sandstone.
SOIL The upper layer of earth in which plants
grow, a black or dark brown material typically consisting of a mixture of organic remains
FIVE DIFFERENT TYPES OF SOIL
SANDY SILTY CLAY
PEATY SALINE
ARE ROCKS AND SOIL DIFFERENT
? YES!! AN EASY DEFINITION IS Rock is one object. and Soil is a mixture of rocks (rather small rocks: dirt),
water, minerals, bacteria, plant, animal, fungi matter etc.
EROSION AFFECTS ROCK AND SOIL
Erosion causes include - gravity, rain, flooding, wind, drought, deforestation, farming, flowing ice
Which effects the rock and soil by
desertification, additional sedimentation, loss of habitat, infertile soils, increased use of soil conditioners and fertilizers, water pollution
EFFECTS OF EROSION!!!!!!!
BIBLIOGRAPHY http://agverra.com/blog/soil-types/ http://answers.yahoo.com/question/ http://en.wikipedia.org/wiki/erosion http://en.wikipedia.org/wiki/List_of_rock_
types http://www.zephyrus.co.uk/rocktypes.ht
ml http://adventuresinscience.edublogs.org
/category/kids-corner/ http://growingchillies.net/growing-chillie
s-soil-tips/ http://www.soilsurvey.com.au/
services.html