Transcript Rocks, Soil and Colors

Soil, Rocks and Color
• Rocks are our world
– Third rock from the Sun
– Solid mineral deposits
• Soil is unconsolidated mineral matter
– Influenced by decayed matter & environment
• Color is an important property of rocks & soil
Rocks and Minerals
• Old rocks, new rocks and rocks of all ages in
between
– 3 billion years to less than 1 million years
• Continuous process called the rock cycle
• Three rock types c
Igneous
sedimentary
Metamorphic
 rock cycle
 rock types
Rocks are composed of one
or more minerals
– Rock Salt - 1 mineral,
halite (NaCl)
– Granite - Several
minerals including:
feldspar, quartz & mica
 Rocks Website
 Rock Identification
Soil is much more than “dirt”
• Critical to life
• How much soil is there?
Color of Rocks and Soil
• Early artists used natural
pigments from rocks and
soil (earth tones)
– Mostly from iron oxides
– Umber, sienna, ochre
• Color used in
classification to asses
Ancient Oil Painting From Pisa
– Physical properties
– Mineral content
– Chemical content
Color of Soil
• Moisture level affects brightness
– Typically moist soil is darker; dry is
brighter
• Soil temperature is affected by color
– Black soil absorbs more solar radiation
• Warms up earlier in the spring for
germinating seeds
• On a hot day in summertime,
temperature can exceed 50 degrees C
Lab Activity
Activity #1
• We will investigate the possibility of using the
ALTA II reflectance spectrometer to distinguish
different rocks and soils
Activity #2
• We will investigate the possibility of using the
ALTA II to determine soil moisture content.