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The quartz in granite begins to melt at 650°C, so if we find a migmatite where quartz has melted in a granitic rock and we know the temperature in the region increased with depth by about 25°C per kilometer, we could estimate the depth that the rock had been at to be about ________.
a. 12.5 km
b. 18.0 km
c. 23.5 km
d. 26.0 km

Respuesta :

maacastrobr

Answer:

d. 26.0 km

Explanation:

If the temperature in the region increases with depth by about 25 °C /km, then at a depth of 2 km the temperature would be 50 °C higher, at a depth of 3 km the temperature would be 75 °C higher and so on.

The only way for finding melted quartz would be if the temperature is at least 650 °C.

  • Temperature = 25 °C /km * Depth

We put the data given by the problem and solve for Depth:

  • 650 °C = 25 °C /km * Depth
  • Depth = 26.0 km

Answer:D 26.0

Explanation: I got it right