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WHAT MODERN EVIDENCE SUPPORTS AND SEALS THE CONCEPT OF PLATE TECTONICS? Need to prove when a piece of the Earth was at a particular location. HOW TO DATE A VOLCANIC ROCK!. STRUCTURE OF ATOMS. Electrons. Neutrons. Protons. Nucleus. 04.11.b1. STRUCTURE OF ATOMS. Neutrons. Protons.
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WHAT MODERN EVIDENCE SUPPORTS AND SEALS THE CONCEPT OF PLATE TECTONICS? Need to prove when a piece of the Earth was at a particular location.
STRUCTURE OF ATOMS Electrons Neutrons Protons Nucleus 04.11.b1
STRUCTURE OF ATOMS Neutrons Protons Nucleus SOME ATOMS OF A CHEMICAL HAVE ADDITIONAL NEUTRONS IN THE NUCLEUS, THESE ARE CALLED ISOTOPES 04.11.b1
Radioactive Isotope “Mother” Stable “Daughters” SOME ISOTOPES ARE UNSTABLE LOSING THEIR NEUTRONS TO FORM NEW ELEMENTS THROUGH THE PROCESS OF RADIOACTIVE DECAY. 04.11.b1
HALF - LIFE Mother 100% 50% 25% Time Period 0% 50% Time Period 75% Daughter Half of all of the original unstable radioactive isotope (mother), shown in green, decay into their stable daughter state (blue), in a given amount of time - the half-life of the radioactive element.
FOR EXAMPLE: “WAYLENIUM” Initial level 2048 Half-life 1 million years
300 2.75
1750 0.2
YOU WILL NEED :- 1. Estimate of Initial Levels of Radioactivity in Isotope 2. Isotope which Loses Radioactivity Appropriate to the Time Periods Investigated.
For example: 10% of decayed “mother” produces “daughter”.
Radioactive Decay Half-life = 1.26 billion yrs! RADIOACTIVE POTASSIUM ISOTOPE - ARGON 09.02.c7
Earth’s History
M. Jardine Science 327, 1206-1207 (2010) Published by AAAS
Geographic North Pole Magnetic North Pole CURRENT POSITION OF EARTH’S MAGNETIC POLES Magnetic South Pole Geographic South Pole
MAGNETIC INCLINATION
MAGNETIC INCLINATION
MAGNETIC INCLINATION
MAGNETIC INCLINATION
MAGNETIC INCLINATION
MAGNETIC INCLINATION
MAGNETIC INCLINATION
MAGNETIC INCLINATION
Direction of Continental Drift from South Pole towards North Pole MAGNETIC INCLINATION AND CONTINENTAL DRIFT
GREEN VOLCANIC ERUPTION AT EXTREME SOUTHERN LATITUDE. GREEN LAVAS SOLIDIFY AND MAGNETIC INCLINATION “FROZEN” IN VOLCANIC ROCKS. 750 mill. yrs. ago 60°S MAGNETIC INCLINATION AND CONTINENTAL DRIFT
GREEN VOLCANIC ROCKS MOVED NORTHWARDS WITH CONTINENT. RED VOLCANIC ERUPTION AT SOUTHERN LATITUDE. RED LAVAS SOLIDIFY AND REDUCED MAGNETIC INCLINATION “FROZEN” IN VOLCANIC ROCKS. 450 mill. yrs. ago 27°S MAGNETIC INCLINATION AND CONTINENTAL DRIFT
RED AND GREEN VOLCANIC ROCKS MOVED NORTHWARDS WITH CONTINENT. BLUE VOLCANIC ERUPTION AT NORTHERN LATITUDE. BLUE LAVAS SOLIDIFY AND REDUCED, NORTHERN, MAGNETIC INCLINATION “FROZEN” IN VOLCANIC ROCKS. 190 mill. yrs. ago 15°N MAGNETIC INCLINATION AND CONTINENTAL DRIFT
BLUE, RED AND GREEN VOLCANIC ROCKS MOVED NORTHWARDS WITH CONTINENT. TAN VOLCANIC ERUPTION AT EXTREME NORTHERN LATITUDE. TAN LAVAS SOLIDIFY AND EXTREME, NORTHERN, MAGNETIC INCLINATION “FROZEN” IN VOLCANIC ROCKS. Present 70°N MAGNETIC INCLINATION AND CONTINENTAL DRIFT
DRILL DOWN THROUGH ROCKS PRESENTLY LOCATED IN NORTHERN CANADA Present 70°N MAGNETIC INCLINATION AND CONTINENTAL DRIFT
WHEN? WHERE? Potassium – Argon Radiometric Dating Magnetic Inclination 2020 70°N 0 0.001 m.yr
WHEN? WHERE? Potassium – Argon Radiometric Dating Magnetic Inclination 0.001 m.yr 70°N 1700 15°N 20 190 m.yr
WHEN? WHERE? Potassium – Argon Radiometric Dating Magnetic Inclination 0.001 m.yr 70°N 190 m.yr 15°N 1500 27°S 60 450 m.yr
WHEN? WHERE? Potassium – Argon Radiometric Dating Magnetic Inclination 0.001 m.yr 70°N 190 m.yr 15°N 450 m.yr 27°S 60°S 1250 70 750 m.yr
WHEN? WHERE? Potassium – Argon Radiometric Dating Magnetic Inclination 70°N 0.001 m.yr 15°N 190 m.yr 27°S 450 m.yr 60°S 750 m.yr