Plate tectonics is Wegener theory of continental drift reworked. The force
needed to move the continents
is proposed to be convection currents in the mantle. … The continents are seen as part of large plates of crust that are moved by the convection currents in the mantle.
Seafloor spreading helps explain continental drift in the theory of plate tectonics. When oceanic plates diverge, tensional stress
causes fractures to occur
in the lithosphere. … At a spreading center, basaltic magma rises up the fractures and cools on the ocean floor to form new seabed.
Supporters of continental drift originally theorized that
the continents moved
(drifted) through unmoving oceans. Seafloor spreading proves that the ocean itself is a site of tectonic activity. Seafloor spreading is just one part of plate tectonics. … Seafloor spreading creates new crust.
Wegener proposed that the continents themselves move, which is untrue. It is the tectonic plates that move. Sea floor
spreading caused the break up of Pangea
, which prompted Wegener to add this in support of his continental drift theory.
How does the theory of plate tectonics combine the idea of continental drift and?
The theory of plate tectonics is what brings together continental drift
and seafloor spreading
. Plates are made of lithosphere topped with oceanic and/or continental crust. The plates are moved around on Earth’s surface by seafloor spreading. Convection in the mantle drives seafloor spreading.
What are 5 pieces of evidence that support continental drift?
The evidence for continental drift included
the fit of the continents; the distribution of ancient fossils, rocks, and mountain ranges; and the locations of ancient climatic zones
.
What are the 4 types of plate tectonics?
- Divergent: extensional; the plates move apart. Spreading ridges, basin-range.
- Convergent: compressional; plates move toward each other. Includes: Subduction zones and mountain building.
- Transform: shearing; plates slide past each other. Strike-slip motion.
What are 3 types of evidence for seafloor spreading?
Several types of evidence from the oceans supported Hess’s theory of sea-floor spreading-
evidence from molten material, magnetic stripes, and drilling samples
.
What causes the tectonic plates to move?
The heat from radioactive processes within the planet’s interior
causes the plates to move, sometimes toward and sometimes away from each other. This movement is called plate motion, or tectonic shift.
What is the theory of seafloor spreading?
Seafloor spreading is a geologic process in which tectonic plates—large slabs of
Earth’s lithosphere—split apart from each other
. … As tectonic plates slowly move away from each other, heat from the mantle’s convection currents makes the crust more plastic and less dense.
What evidence supports the theory of plate tectonics?
Evidence from fossils, glaciers, and complementary coastlines
helps reveal how the plates once fit together. Fossils tell us when and where plants and animals once existed. Some life “rode” on diverging plates, became isolated, and evolved into new species.
What are the principles of the plate tectonics theory?
The key principle of plate tectonics is that
the lithosphere exists as separate and distinct tectonic plates, which float on the fluid-like (visco-elastic solid) asthenosphere
What are the 4 pieces of evidence for continental drift?
They based their idea of continental drift on several lines of evidence:
fit of the continents, paleoclimate indicators, truncated geologic features, and fossils
.
What are 6 pieces of evidence that support continental drift?
- Fossils.
- Continents fit like Puzzle Pieces. Matching fossils preserved in rocks of the same age but found on different continents. Ex. …
- Matching Rocks. Puzzle – like fit of continental shelves. Ex. …
- Mountain Ranges.
- Glacier Striations.
- Coal Beds.
What is the evidence of Pangea?
Glacial deposits, specifically till, of the same age and structure are found on many separate continents that would have been together in the continent of Pangaea. Fossil evidence for Pangaea includes
the presence of similar and identical species on continents that are now great distances apart
.
