what is earth science?
DESCRIPTION
What is Earth Science?. The study of the earth’s systems and the interactions between these systems . Divided into 5 fields of study. Astronomy Meteorology Geology Oceanography E nvironmental Science. What are Earth’s Systems?. Geosphere Atmosphere Hydrosphere Biosphere. Geosphere. - PowerPoint PPT PresentationTRANSCRIPT
What is Earth Science?The study of the earth’s systems
and the interactions between these systems
Divided into 5 fields of study• Astronomy• Meteorology• Geology• Oceanography• Environmental Science
What are Earth’s Systems?
•Geosphere•Atmosphere•Hydrosphere•Biosphere
Geosphere
Everything from the crust to the center of the earth.
Geosphere
The Forces Within the Earth Plate Tectonics (Ch 17)
Earthquakes (Ch 19)Mountain Building ( Ch 20)
Volcanism (Ch 18)
In text turn to page 956• Observe the continents • Does the shapes & position of the continents
suggest they were once joined? Which Ones??
Early Observations• 1500’s a Abraham Ortelius Dutch
cartographer noticed the apparent fit of continents on either side of the Atlantic Ocean
• He proposed that N & S American was separated from Europe and Africa by earthquakes and floods…
• Referenced as creator of the modern atlas
20th Century • 1912 Alfred Wagner presented his
hypothesis that continents were slowly drifting around the Earth• Developed the continental drift theory
Continental Drift Theory• Earth’s continents had been joined as
a single landmass that broke apart and sent the continents adrift • Single Landmass supercontinent
named Pangaea • Pangaea Greek word means all the
Earth
Pangaea
• Break up about 200 million years ago.
• Observed: puzzle like fit.
• Evidence: rock, fossil and climate
Rock EvidencePredicted: When Pangaea broke apart large geologic structures such as mountain ranges
fractured during separationInvestigated: Areas of similar rock types on
opposite sides of the oceansView Figure 17.3 in TEXT p 470 Rock Layers in the Appalachian Mountains are identical to mountains in Greenland & Europe
Fossil Evidence• Predicted: Land animals such as Lystrasaurus
or Cynognathus could not have swum the great distances
• Investigated: Similar fossils from several different plants & animals found on widely separated continents
• Carbon dating of the fossils support the time frame of Pangaea breakup
• View Figure 17.3 in TEXT p 470
Climatic Evidence• Predicted: Fossils of plants like Glossopteris grew in
temperate climates and found all over the world
• Investigated: The area that separated these fossils is too large to have a single climate
• For example fossil record of the plant in Antarctica & South Africa and S American
• View Figure 17.3 in TEXT p 470
Climatic Evidence• Coal Deposits : Existence of beds in Antarctica Frozen climate once had tropical climate • Glacial Deposits : Found in parts of Africa,
India South America Locations of these continents too warm for ice
formation
Continental Drift Theory Flaws
• 1st What force could push large mass over great distances
• 2nd How the continents could move were through something solid like earth’s crust
• They questions were the reasons why Wegener’s theory was rejected until the 1950s