This is an irregular verb and the conjugations need to be memorized. A short lesson explains how. Mentir - French Verb Conjugations Learn how to conjugate mentir, an irregular -ir French verb. This is not an easy verb to conjugate, so you will need a good lesson to show you how.
Metamorphism occurs because some minerals are stable only under certain conditions of pressure and temperature. When pressure and temperature change, chemical reactions occur to cause the minerals in the rock to change to an assemblage that is stable at the new pressure and temperature conditions.
By Andrew Alden. Metamorphic rocks are the third great class of rocks. These are what happens when sedimentary and igneous rocks become changed, or metamorphosed (changed in form), by conditions underground. The four main agents that metamorphose rocks are heat, pressure, fluids and strain.he Four Agents of Regional Metamorphism. Heat and pressure usually work together, because both rise as you go deeper in the Earth. At high temperatures and pressures, the minerals in most rocks break down and change into a different set of minerals that are stable in the new conditions.