Contact Metamorphism in Southern California

Abstract

A highly condensed introduction to "Contact metamorphism in southern California" is obviously not the place in which to indulge in semantic niceties nor to engage in terminological tussles, and thus the title is not intended to reflect a carefully delimited concept. Instead it is freely admitted that in some of the examples to be cited, such terms as "contact metasomatic," "pyrometasomatic," "optalic" or "thermal metamorphic," "hydrothermal," "pneumatolytic," and even "injection metamorphism" might be more precisely appropriate. Suffice it to say that "contact metamorphism" will be herein employed in its broader connotations. There is an old adage which states that "it takes two to make a quarrel." Likewise, it takes two (rocks) to make a contact, and unless one of these rocks was at one time pretty hot, preferably indeed in the magmatic state, there is likely to be no contact metamorphism as such. With the concept of contact metamorphism thus reduced to these two essentials, an invaded rock and an invading magma, let us survey the southern California field.