Abstract
Samples of macrofabric data obtained from colluvial deposits near the late-Wisconsinan glacial margin display widely divergent characteristics. Those from highly weathered and jointed sandstone plot as girdle distributions. Samples from red colluvium of early-Wisconsinan age form moderately strong clusters. Fabrics from shallow depth in medium-textured brown colluvium of late-Wisconsinan age generally have modes aligned with the local slope but are weak, and appear to have been modified by frost heaving. Clasts in the basal layers of an overlying loess unit were emplaced by frost heaving from the brown colluvium and have very weak or uniform fabrics. Particle shape exerts an influence on fabric strength in the brown colluvium, with samples composed of more elongated clasts displaying stronger fabrics. Fabrics from near-surface deposits show generally weaker shape and strength characteristics and higher inclinations than those the depth. Calculated seasonal frost penetration is consistent with the depth to which weaker, more sleeply inclined fabrics are found. Sampling in relict periglacial deposits should be performed only below the level of disturbance by seasonal frost.
Original language | English (US) |
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Pages (from-to) | 145-156 |
Number of pages | 12 |
Journal | Geografiska Annaler, Series A: Physical Geography |
Volume | 83 |
Issue number | 3 |
DOIs | |
State | Published - 2001 |
Keywords
- Clast fabric
- Colluvium
- Eigenvalues
- Frozen ground
- Mass movement
- New York
- Periglacial environment
- Permafrost
- Sampling
- Solifluction
- Spherical statistics
ASJC Scopus subject areas
- Geography, Planning and Development
- Geology