There are two types of intrusive igneous rocks: concordant and discordant. Concordant intrusive igneous rocks do not disrupt or destroy existing structures. Conversely, discordant igneous rocks cut across previously formed strata effectively destroying and consuming what had previously formed. An axampel of a discordant rock formation is that of the batholith which is a massive pluton (a body of plutonic rock) that has melted and assimilated most of the existing rock structures it has invaded. Concordant rock formation can be broken down into two further categories: sill, and laccolith. A sill is the intrusion of magma between strate without disturbing or destroying the surrounding layers. Laccolith is a chamber, fed by a magma pipe, that grew dome like, and in the process pushed the surrounding strata into a bulge without destroying it. This picture is of granite used at Canada Place in downtown Edmonton; certain types of granite form through intrusive processes.
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