Answer:
C. plagioclase
Explanation:
From the magma silicate crystals are formed successively when the magma temperature reaches the typical melting temperature for each type of crystal. The first crystals formed at high temperatures can then change their composition or dissolve again. In this way the crystals already formed contribute their ions, molecules and atoms to magma and combine again forming new crystals whose melting temperature is lower than that of the first crystals formed. The new crystals are said to be stable at the lowest temperatures set now. These processes of change are called reactions. As several successive reactions occur as the magma temperature decreases the ordered series of reactions is called the BOWEN series in honor of the Canadian scientist who formulated this concept. There are two types of reactions, the continuous reaction and the discontinuous reaction.
<u>
By continuous reaction a crystal formed at high temperatures such as a plagioclase rich in the Ca2 +</u> component gradually varies its composition by replacing a portion of the Ca2 + ions with the Na + ions and a portion of the Al3 + ions with the Si4 + ions. To maintain its neutrality, the replacement of Ca2 + by Na + is coupled with the replacement of Al3 + by Si4 +. The series of continuous reaction starts from the plagioclase rich in Ca2 +, passes through several plagioclase of intermediate composition towards the plagioclase rich in Na +
Pacific and north american
In the mid-twentieth century and corroborated ever since, researchers dredging the seafloor could not find any materials older than 180 million years.
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What do you understand by seafloor ?</h3>
The surface of an ocean or sea: seafloor According to this theory, the Earth's crust is divided into a number of enormous plates that together form the continents and ocean floors and are supported by a warm, plastic "mantle" beneath the surface. Mr. Walter Sullivan
Deposits of common minerals like copper, zinc, nickel, gold, silver, and phosphorus can be found on the seafloor. These deposits are nodules on silt from the abyssal plain that are typically 3 to 10 centimeters (1 to 4 inches) in diameter and appear as crusts on volcanic and other rocks.
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Answer:
The San Andreas Fault is a continental transform fault that extends roughly 1,200 kilometers (750 mi) through California. It forms the tectonic boundary between the Pacific Plate and the North American Plate, and its motion is right-lateral strike-slip (horizontal). ... It was formed by a transform boundary.
B) Faulting
Layers of strata in the earths crust naturally slide along each other. Sometimes friction or blockage causes this process to stop, until enough pressure builds up to overcome whatever the resistant force is. Faulting is the process by which this pressure forces the strata to continue their movement, often producing cracks in the involved strata, and causing earthquakes and tremors in the event of an intense pressure release.
-Ps Bri
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