Exploring regional scale metamorphic fabrics in the Yukon Tanana terrane and environs using quantitative domain analyses

Jonathan Saul Caine; James V. Jones

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USGS · 70219116

Exploring regional scale metamorphic fabrics in the Yukon Tanana terrane and environs using quantitative domain analyses

Jonathan Saul Caine·James V. Jones

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Abstract

Metamorphic rock fabrics such as foliations and lineations provide a rock record of numerous deformational characteristics in the Earth’s crust. When spatial information is combined with fabric data collected at points on geologic maps, the nature and consistency of metamorphic fabrics can be explored through structural domain analysis. This is particularly useful in large regions where there is not well-established stratigraphy and where bedrock exposures are limited. Domains that contain distinctive orientations and patterns of fabrics can be constructed on the basis of several different parameters, but in folded, polydeformational regions cylindricity can be particularly useful. Distinct domains of cylindrical folding can sometimes be determined where poles to foliations show characteristic patterns on equal-area projections and lie perpendicular to a single axis in space. Additionally, the patterns of elements such as fold axes and mineral lineations can be used in conjunction with foliation data to refine domains and confirm parameters such as coaxiality.

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Conference Paper

Source-reported bounding extent: 61.41775026352097° to 67.44122869796351° latitude; -156.59912109375° to -134.14306640625° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Jonathan Saul Caine, James V. Jones. 2020. Exploring regional scale metamorphic fabrics in the Yukon Tanana terrane and environs using quantitative domain analyses. https://pubs.usgs.gov/publication/70219116

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