The 1982 changes include using precise numbers from laboratory tests, requiring the presence of 30 percent or more sand or gravel before adding the descriptive term sandy or gravelly, and re-defining organic clay and organic silt
. Additionally, the names for the soil groups were formalized; for example, there is a specific definition for what silly clay means.
The organic silt is mostly retained in reservoirs, instead of fertilizing the downstream floodplains.
With increased turbine discharge, the washed organic silt mixes with water and passes down.
Nearly 9 m of frozen organic silt (locally known as "muck") had overlain the bones at Nugget Gulch.
The bison (Bison sp.) radio-ulna was found nearby the following year, partly buried in the surface of apparently disturbed organic silt.
The ash lay about 1 m above the gold-bearing gravel (which in turn overlay siliceous schist bedrock with blocky weathering, and underlay about 9.1 m of organic silt ["muck" in mining terms]) in patches nearly 2 m long with a maximum depth of 25 mm.
The Younger Dryas sequence could generally be recognized in the field as a distinct lithological unit: a light-colored band of silty clay or organic silt bracketed by darker, more organic sediment.
Depth below sediment/water interface (cm) Sediment lithology Splan Pond Mayflower Lake Dark brown gyttja, grading to organic silt toward bottom 0-468.5 0-350 Light brown organic silt 468.5-472.5 ...
At this site, the lithological change from organic silt to Younger Dryas clay (drop in LOI from 19 to 4% across only 1.5 cm) occurs in only 25 yr.
MH Elastic Silt OH Organic Clay CH Fat Clay OL Organic Silt
Pt Peat To date, the ASTM standards that use the Uniform Soil Groups include:
A portion of the organic silt (sample site B) was sampled for fossil insects and pollen.
4A) consists of organic silt laterally deformed by massive ground ice (Fig.