Harry Hess’s hypothesis about seafloor spreading had collected several pieces of evidence to support the theory. This evidence was from the investigations of the molten material, seafloor drilling, radiometric age dating and fossil ages, and the magnetic stripes .
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 are the evidences of seafloor spreading?
Abundant evidence supports the major contentions of the seafloor-spreading theory. First, samples of the deep ocean floor show that basaltic oceanic crust and overlying sediment become progressively younger as the mid-ocean ridge is approached, and the sediment cover is thinner near the ridge .
What is the evidence for seafloor spreading quizlet?
Several types of evidence supported Hess’s theory of sea-floor spreading: eruptions of molten material, magnetic stripes in the rock of the ocean floor, and the ages of the rocks themselves .
What are the evidences of plate movements?
There is variety of evidence that supports the claims that plate tectonics accounts for (1) the distribution of fossils on different continents , (2) the occurrence of earthquakes, and (3) continental and ocean floor features including mountains, volcanoes, faults, and trenches.
What is the major evidence that sea floor spreading creates new lithosphere?
When the Earth’s magnetic field reverses, the magnetized minerals align in the opposite direction. The record of magnetic reversals is carried away from each side of the spreading center of a mid-ocean ridge , showing that the molten rock is creating new lithosphere.
How did Harry Hess prove seafloor spreading?
Hess discovered that the oceans were shallower in the middle and identified the presence of Mid Ocean Ridges , raised above the surrounding generally flat sea floor (abyssal plain) by as much as 1.5 km. ... This created new seafloor which then spread away from the ridge in both directions.
What evidence first supported the theory of seafloor spreading?
The scientists used a remote controlled submarine to explore the deep ocean trench. The evidence that first supported the theory of seafloor spreading was when scientists found vents . The Juan del Fueca Ridge has at least four major, high temperature vent fields.
What is an example of seafloor spreading?
Seafloor spreading occurs along mid-ocean ridges —large mountain ranges rising from the ocean floor. The Mid-Atlantic Ridge, for instance, separates the North American plate from the Eurasian plate, and the South American plate from the African plate. ... The Mid-Atlantic Ridge, for instance, is a slow spreading center.
What are the 4 types of tectonic plate movement?
- 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 the 5 evidences of continental drift theory?
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 3 pieces of evidence for Pangea?
Alfred Wegener, in the first three decades of this century, and DuToit in the 1920s and 1930s gathered evidence that the continents had moved. They based their idea of continental drift on several lines of evidence: fit of the continents, paleoclimate indicators, truncated geologic features, and fossils .
Who proved that the seafloor is spreading?
The seafloor spreading hypothesis was proposed by the American geophysicist Harry H. Hess in 1960.
How does the topography of the seafloor give evidence for seafloor spreading?
The features of the seafloor and the patterns of magnetic polarity symmetrically about the mid-ocean ridges were the pieces that Hess needed. ... Hess called this idea seafloor spreading. Magma at the mid-ocean ridge creates new seafloor.
How does Earth’s magnetic field provide evidence for seafloor spreading?
As it cools it becomes permanently magnetized in the direction of the Earth’s magnetic field . ... This creates a symmetrical pattern of magnetic stripes of opposite polarity on either side of mid-ocean ridges. These patterns of stripes provide the history of seafloor spreading.
What did Alfred Wegener discover?
In 1912 Alfred Wegener (1880-1930) noticed the same thing and proposed that the continents were once compressed into a single protocontinent which he called Pangaea (meaning “all lands”), and over time they have drifted apart into their current distribution.
