extrusive rock


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Related to extrusive rock: Intrusive Rock

extrusive rock

[ik′strü·siv ′räk]
(geology)
References in periodicals archive ?
Moreover, the presence of a complex variety of intrusive and extrusive rocks suggest that an extinct volcanic crater may in part underlie a large swamp in the main Dagobert zone.
There was abundant disseminated and stringer sulfide mineralization in the extrusive rocks and associated quartz veining.