8245

• UCREFRP Catalog Number: 8245
• Author: Schmidt, J. C., K. L. Orchard and S. P. Holman.
• Title: Spatial and Temporal Patterns of Habitat Availability in Desolation and Gray Canyons.
• USFW Year: 1996.
• USFW - Doc Type: Logan, Utah.
• Copyright Material: NO

APPENDIX A
ALLUVIUM
ALLUVIAL DEPOSITS OF THE GREEN RIVER IN DESOLATION AND GRAY
CANYONS
Bars formed as channel margin deposits
submerged sand Fine grained alluvium submerged but visible at the
time of mapping
channel margin silt Terrace like deposit with abundant silts and muds.
Deposit is highly cohesive, and is slippery and sticky
when wet. Bedding is horizontal and bedforms such
as ripples are absent. Deposits are formed by vertical
accretion.
channel margin sand Sand occurring along the margin of the channel in
zones of downstream flow. Deposits are generally
thin. Most often horizontally bedded, but may contain
ripples.
mid channel sand bar Sand bar occurring in downstream flow and
unattached from the bank
vegetated channel margin fines Densely vegetated terrace like fine grained alluvial
deposits, occurring within the active channel
cottonwood terrace Terrace like deposit of fine grained alluvium
bordering the channel margins. Cottonwood terrace
is higher in elevation than channel margin silts or
channel margin sand deposits. This terrace is often
vegetated by mature Tamarisk, Box Elder, and
Cottonwood trees. Non-riparian vegetation such as
cactus and sage brush can be found on this surface.
Driftwood at this elevation is highly weathered, but
contains evidence of historic inundation, such as sawn
logs in drift piles.
high terrace Terrace like deposit of fine grained alluvium. High
terrace is higher in elevation than cottonwood terrace.
High terrace is often vegetated with pinion and
juniper trees and has abundant cryptogramic crusts
on the soil surface. Does not contain evidence of
historic inundation. Exposed deposits often show
intertounging with debris fan material.
undifferentiated terrace cottonwood/high terrace undifferentiated