期刊
GEOLOGY
卷 38, 期 3, 页码 263-266出版社
GEOLOGICAL SOC AMER, INC
DOI: 10.1130/G30492.1
关键词
-
类别
资金
- University of New Mexico
- Kent State University Research Council
In the Teton River Canyon, eastern Idaho, the ca. 2.06 Ma, 130-m-thick Huckleberry Ridge Tuff exhibits large-scale rheomorphic fold geometries defined by eutaxitic fabrics parallel to both the primary internal zonation and the basal contact with older strata. Paleomagnetic data from a large-amplitude (>150 m), northwest-trending, overturned fold near the failed Teton Dam indicate folding above maximum magnetization unblocking temperatures (>580 degrees C). The in situ characteristic remanent magnetization (ChRM) direction is indistinguishable from previous studies of undeformed Huckleberry Ridge Tuff, and a fold test is negative (k minimized at 100% unfolding). Anisotropy of magnetic susceptibility data reveal magnetic foliation planes that dip northeast, roughly parallel to the axial surface of the fold. Because deformed and undeformed Huckleberry Ridge Tuff exposures preserve the same anomalous ChRM direction, large-scale rheomorphic structures in the tuff must have formed rapidly at high temperatures shortly after development of compaction fabrics. Post-welding, high-temperature deformation is consistent with field evidence indicating rapid, plastic secondary deformation of much of the tuff prior to devitrification.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据