UBC Theses and Dissertations
The geology of the Ecstall-Quall Rivers area, British Columbia. Padgham, William Albert
The Ecstall-Quaal Rivers area is in the Skeena Mining Division of western British Columbia. The area is underlain by intrusive rocks of the Coast Range Complex Batholith and by older rocks of the Ecstall metamorphic complex, the "Ecstall Septum". A thick group of impure clastic sediments including minor calcareous beds and lenses have undergone extreme dynamothermal metamorphism to give schist, gneiss, quartzite, and marble. Although the amount of cataclastic or dynamic metamorphism has been very high, the minerals present are usually in the lower grades of the amphibolite facies. Retrogressive metamorphism of biotite, and hornblende to sericite and chlorite is common in most of the metamorphic rocks. The original sediments would be those expected under unstable shelf conditions. It appears that the granodiorite which borders the septum on the east and west, has reached its present position by some type of intrusive action. It is certainly not a "metamorphic" or "metasomatic" granite.
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