Contact metamorphism<span> is a type of </span>metamorphism<span> where rock minerals and texture are changed, mainly by heat, due to </span>contact<span> with magma. </span>Regional metamorphism<span> is a type of </span>metamorphism<span> where rock minerals and texture are changed by heat and pressure over a wide area or region.</span>
Catalytic ozone destruction occurs in the stratosphere where the reactions involving bromine, chlorine, hydrogen, nitrogen and oxygen gases form compounds that destroy the ozone layer. The reactions uses a catalyst (speeds up the reaction) in a two step reaction. considering chlorine the reactions appears as follows;
step 1
Cl + O3 = ClO + O2
step 2
ClO + O = Cl + O2
Where by chlorine is released to destroy the ozone layer, this takes place many times even with the other elements (hydrogen, bromine, nitrogen) and the end result is a completely destroyed Ozone layer