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What else can I help you with?
What type of boundaries are subduction zones associated with?
Convergent oceanic - continental and oceanic - oceanic boundaries.
Which type of plate is denser continental or oceanic?
oceanic as it is colder; therefore denser
What happens when an oceanic plate collides with a continental plate?
when oceanic crust and continental crust collide, the oceanic crust sinks down beneath the continental crust. this is called subduction.
What evidence supports the theory of plate tectonics?
The shape of the continents, the distribution of earthquakes, the symmetric magnetic banding of the sea floor ether side of the mid oceanic ridges, the mid oceanic ridges, back arc basins, deep sea trenches, the fiery ring of the Pacific, The distribution and chemistry of volcanoes, atolls, paleo magnetism, fossil evidence and the distribution of species. (there may be more evidence).
Why does the Earth's size remains the same despite of what is happening at the mid-oceanic ridge?
An equal amount of oceanic crust is being subducted at the convergent plate boundaries as is being created at the mid-oceanic ridge.
What struture on the seafloor would have magnetic striping?
The Mid Ocean Ridge would have magnetic striping. As the seafloor expands, new oceanic crust is spread in either direction. As this process continues over many years, the magnetic poles may switch, altering the magnetism in the new crust. The poles will switch back and forth, producing the magnetic striping that is easily discernible when examining the Mid Ocean Ridge and surrounding seafloor.
What Causes of magnetic striping?
Magnetic striping on the ocean floor is caused by the movement of tectonic plates. As new oceanic crust is formed at mid-ocean ridges, Earth's magnetic field causes iron-rich minerals in the crust to align and record the direction of the magnetic field at that time. This results in alternating patterns of magnetic polarity stripes on the ocean floor.
What concepts did magnetic striping reveal to scientists about the rock on either side of a spreading ridge?
The pattern of magnetic striping on one side of the ridge was a mirror image of the striping on the other side of the ridge, indicating that the plates were moving equally in opposite directions, giving a plausible explanation for continental drift theory. Before this discovery, no evidence of a mechanism for plate tectonics existed. It was obvious after this discovery, that new crust was being created at the ridges.
What does magnetic striping tell us about the age of rocks?
If you know how many stripes away from the mid-ocean ridge the rock is and you know how frequently the earth's poles flip you can use the stripes like rings on a tree to measure the age of that rock.
Why does magnetic striping happen?
The plate tectonics based theory ha a three pronged aproach; both the zebra-like magnetic striping and the construction of the mid-ocean ridge system, the seafloor spreading hypothesis (SFS) quickly gained converts and represented another major advance in the development of the plate-tectonics theory. Furthermore, the oceanic crust now came to be appreciated as a natural "tape recording" of the history of the geomagnetic field reversals (GMFR) of the Earth's magnetic field. Nowadays, extensive studies are dedicated to the calibration of the normal-reversal patterns in the oceanic crust on one hand and known timescales derived from the dating of basalt layers in sedimentary sequences (magnetostratigraphy) on the other, to arrive at estimates of past spreading rates and plate reconstructions.
How did scientists discover that rocks get older from the mid ocean ridge?
They discovered a pattern of reverse and normal polarity in the rock bodies of the ocean floor that indicated that oceanic crust was constantly being formed over time. Polarity shifts in the Earth had already been noted in continental crustal rock. With the advent of radiometric dating, core samples were taken and dated, confirming that the youngest rock is found at the ridge and rock age advances with distance from the ridge.
How would the history of reversals show itself on the ocean floor?
The history of reversals can be observed on the ocean floor through magnetic striping. When new oceanic crust is formed at mid-ocean ridges, magnetic minerals align with the Earth's magnetic field. Over time, as the Earth's magnetic field reverses, these minerals record the reversals in alternating magnetic stripes on the ocean floor. This provides evidence for the history of reversals.
How were scientists able to use rock on the ocean floor to determine that the Earth and magnetic field has changed direction?
Scientists studied the alignment of magnetic minerals in oceanic rocks to determine that the Earth's magnetic field has undergone reversals in polarity. By analyzing the magnetic "stripes" on the ocean floor, they found alternating bands of rocks with normal and reversed polarity, suggesting that Earth's magnetic field has changed direction over time.
What is the primary evidence that forms the basis of seafloor spreading?
The primary evidence for seafloor spreading comes from magnetic striping patterns on the ocean floor. These patterns show alternating bands of normal and reversed polarity, indicating that new oceanic crust is being continuously formed at mid-ocean ridges and spreading away from the ridge axis.
Used as evidence for sea-floor spreading?
Magnetic striping on the ocean floor is used as evidence for seafloor spreading. As new oceanic crust forms at mid-ocean ridges, Earth's magnetic field is recorded in the rocks in alternating patterns of normal and reversed polarity. This provides support for the idea that new crust is continuously being created at mid-ocean ridges and spreading away in opposite directions.
How does oceanic crust record polarity?
Oceanic crust records polarity through the alignment and orientation of magnetic minerals within the rock as it solidifies near mid-ocean ridges. These minerals become magnetized parallel to Earth's magnetic field at the time of their formation and preserve this polarity orientation as the crust moves away from the ridge. By analyzing the magnetic stripes on the ocean floor, scientists can determine the history of magnetic reversals and the movement of tectonic plates.
How seismic studies support seafloor spreading?
Seismic studies show evidence of mid-ocean ridges where new oceanic crust is forming, supporting the theory of seafloor spreading. By analyzing seismic waves, scientists can map the structure of the ocean floor and identify areas of tectonic activity where plates are moving apart. Additionally, seismic data reveals the presence of magnetic striping on the seafloor, further supporting the idea of seafloor spreading.
