The Howell Creek suite, southeastern British Columbia: Mid-Cretaceous alkalic intrusions and related gold deposition in the Canadian Cordillera.

摘要

The mid-Cretaceous alkalic Howell Creek suite of southeastern British Columbia, consists of coeval, hypabyssal, intrusions of alkali feldspar syenite, foid syenite, megacrystic syenite, and gabbro, with associated intrusive breccias. These rocks are spatially associated with low-grade gold mineralisation.; The results of x-ray fluorescence analysis (XRF) and inductively coupled plasma mass-spectrometry (ICP-MS) provide trace and rare earth element data which indicate a geochemical association between the intrusive phases. This augments the results of 40Ar/39Ar dating of K-feldspar phenocrysts which confirms coeval emplacement of the intrusions at ∼102 Ma.; The Howell Creek suite and its associated style of mineralisation bears similarities to other mid-Cretaceous intrusive suites occurring along the Canadian Cordillera resulting from anatectic melting of thickened crustal rocks.; The Howell Creek area lies in a unique position proximal to a crustal lineament, and its potential influence on the location and geochemistry of the Howell Creek suite is discussed.