Question

in contact metamorphism is the source of increased temperature and pressure is
a local intrusive heat source
impact metamorphism
the increase in temperature with increasing depth of burial
due to increased rate of radioactive decay
under extreme pressure and temperature conditions, sedimentary rock will change into an igneous rock.
true
false

Explanation:

• For the first question: Contact metamorphism is mainly caused by a local intrusive heat source (like magma intrusion) which heats up the surrounding rocks. Impact metamorphism is a different type (caused by impacts), increase in temperature with depth is related to regional metamorphism (not just contact), and increased radioactive decay rate is not the main source for contact metamorphism.
• For the second question: Under extreme pressure and temperature, sedimentary rock changes into metamorphic rock, not igneous rock. Igneous rocks form from cooling of magma or lava.

Answer:

1. a local intrusive heat source
2. false