Unraveling Plate Tectonics: Impact of Earth's Geological Formations
Exploring the intricate relationship between plate tectonics and significant geological events such as Permian-Triassic extinctions, lava eruptions, and bolide impacts. Delve into the origins of Earth's tectonic movements and their profound impact on the planet's history.
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DID PLATE TECTONICS START WITH A BIG BANG? David Moerdyk
Another Unlikely Coincidence Permian-Triassic 252 Ma Siberian Traps Extinctions Age Large Lava Eruptions Cretaceous-Tertiary 65 Ma Deccan Traps
Main Cause Permian-Triassic 252 Ma Siberian Traps Extinctions Age Large Lava Eruptions Bolide Impact Cretaceous-Tertiary 65 Ma Deccan Traps Chicxulub
Impact Causes Lava Eruptions Permian-Triassic 252 Ma Siberian Traps Extinctions Age Antipodal Eruptions Bolide Impact Cretaceous-Tertiary 65 Ma Deccan Traps Chicxulub
PT Impact Permian-Triassic 252 Ma Siberian Traps Pacific Hawaiian Extinctions Age Antipodal Eruptions Bolide Impact Hotspot Cretaceous-Tertiary 65 Ma Deccan Traps Chicxulub
CT Hotspot Permian-Triassic 252 Ma Siberian Traps Central Pacific Hawaiian Extinctions Age Antipodal Eruptions Bolide Impact Hotspot Cretaceous-Tertiary 65 Ma Deccan Traps Pacific NW Yellowstone
Making of a Hotspot
Tube Above 660 km, Ball Below B. Schmandt EPSL May 2012
CT Hotspot Permian-Triassic 252 Ma Siberian Traps Central Pacific Hawaiian Extinctions Age Antipodal Eruptions Bolide Impact Hotspot Impact-Eruption Relative Position Type of Impact Result Residual Cretaceous-Tertiary 65 Ma Deccan Traps Pacific NW Yellowstone 170 Near Vertical Bolide Destroyed Iridium Rich Layer
PT Hotspot Permian-Triassic 252 Ma Siberian Traps Central Pacific Hawaiian ~120 Extinctions Age Antipodal Eruptions Bolide Impact Hotspot Impact-Eruption Relative Position Type of Impact Result Cretaceous-Tertiary 65 Ma Deccan Traps Pacific NW Yellowstone 170 Grazing Most of Bolide Escapes to Space No Iridium Rich Layer Near Vertical Bolide Destroyed Residual Iridium Rich Layer
Hotspot Thermal Path Extends to Coast M. Obrebski Geophys. J. Int 2011
Cordilleran Volcanic Activity Begins 61 Ma J.K. Madsen Geosphere, Feb. 2006
PT Hotspot Permian-Triassic 252 Ma Siberian Traps Central Pacific Hawaiian ~120 Extinctions Age Antipodal Eruptions Bolide Impact Hotspot Impact-Eruption Relative Position Type of Impact Result Cretaceous-Tertiary 65 Ma Deccan Traps Pacific NW Yellowstone 170 Grazing Most of Bolide Escapes to Space No Iridium Rich Layer Jurassic Quiet Zone Ontong Java Plateau Breakup of Pangea Near Vertical Bolide Destroyed Residual Iridium Rich Layer Geologic Evidence Cordilleran Volcanism 61 Ma
Global Crustal Model Timeline Subduction Plate Tectonics: Cooling Period: New Oceanic Crust Becomes Negatively Buoyant Intraplate Tectonics: Global Continental Crust Crust Hardens Small Plate Movement Global Crust Formation: Constant Generation Pliable Crust Formation of Keels 4.5 Ga 3.9 Ga 0.25 Ga 0.2 Ga 0.0 Ga Pangea Breakup Hawaiian Impact Big Bang
Evidence From Zircons Continuous Generation Mixing from Diverse Sources Indicates Pliable Crust Episodic Generation Indicates Rigid Crust A.I.S. Kemp EPSL 2010
Keel Structure Formed by Differentiation Low Melt Temperature Interior High Melt Temperature Thermal Boundary
Subduction Generated Geologic Structures Are Not Older than 1 Ga See: W.B. Hamilton, GSA Today 2003 R.J. Stern, Geology 2005
Paleomagnetism Shows Little Movement Between the Best Measured Cratons Based on Z.X. Li Precambrian Research 2008
Keel Structure is Fragile Longevity indicates little stress. Lack of kimberlites older than 200 Ma indicates little stress until the breakup of Pangea. Allowed widespread destruction of crust.
Reconstruction of Pangea Different Edge of Baltica Connected to Laurentia
Result: Circular Pangea Landmass Tethys Sea filled with Southeast Asia Landmass and extension of Tibet
Other Planets Have Been Hit Mars Terrain Dichotomy Attributed to Bolide Impact Venus resurfaced 300-500 Ma. Could a bolide impact caused this? 1,300 km Caloris Basin on Mercury
Moon is Bolide? Requires South Pole-Aitken Basin to be formed by impact. QuickMap : NASA/GSFC/Arizona State University 2016
Bolide from Outer Solar System? ~10 Dwarf Planets have been discovered in Kupier Belt 400-1700 Dwarf Planets estimated in Oort Cloud
