Geologic Unconsolidated Mineral Substrate surface is 5% to < 30% Gravel (particles 2 millimeters to < 4,096 millimeters in diameter).

Name Change

Membership Change

Editorial Change (defintion re-worded)

S

When classifying Mixes, or when there is a need to identify specific particle sizes beyond the Subgroup definitions, the Subgroup terms for the Gravel Group (Boulder, Cobble, Pebble, Granule), Sand Group (Very Coarse Sand, Coarse Sand, Medium Sand, Fine, Sand, Very Fine Sand), and Mud Group (Silt, Silt-Clay, Clay) may optionally be substituted for the Group term. Examples: Muddy Sandy Gravel -> Silty Sandy Gravel, Slightly Gravelly Sandy Mud -> Slightly Gravelly Sandy Clay, Gravelly Muddy Sand -> Gravelly Muddy Coarse Sand, Slightly Gravelly Sand -> Slightly Gravelly Medium Sand

Due to the importance of different particle sizes of Gravel as habitat for many organisms, Gravel subgroup particle sizes (Boulder, Cobble, Pebble, Granule) must be identified whenever particle sizes are known or can be estimated within any mix and at any level of classification. Examples: Gravel Mixes -> Pebble Mixes, Muddy Sandy Gravel -> Muddy Sandy Cobble, Gravelly Sand -> Bouldery Sand

When classifying mixes of two different Gravel Subgroup particle sizes, use combinations of the Subgroup unit names with the overall dominant size first. Examples: Boulder-Cobble, Cobble-Boulder, Cobble-Granule, Pebble-Granule, Granule-Boulder.

Gravelly Mixes

cmecs:CMECS_00000395

Gravelly Mixes

Anthropogenic Impact, aRPD and RPD Depth, Benthic Depth Zones, Co-Occurring Elements, Coral Reef Zone, Energy Intensity, Induration, Percent Cover (Fine), Mineral Precipitate, Percent Cover (Coarse), Seafloor Rugosity, Small-Scale Slope, Substrate Descriptor, Substrate Layering, Surface Pattern, Temporal Persistence

1.3.2.2

Original Unit

CMECS Substrate Component: Substrate Group