LOCATION CORATANK VA+NC

Tentative Series
JDK-RBT
06/2026

CORATANK SERIES

MLRA(s)--153B
Depth class--Very deep
Drainage class--Very poorly drained
Parent material--Herbaceous organic material over loamy estuarine deposits
Geomorphic location--Estuarine tidal marshes
Slope range--0 to 1 percent
Mean annual air temperature--17 degrees C (63 degrees F)
Mean annual precipitation--1270 millimeters (50 inches)

TAXONOMIC CLASS: Loamy, mixed, euic, thermic Terric Haplosaprists

TYPICAL PEDON: Coratank muck in an oligohaline marsh at about sea level (colors are for moist soil unless otherwise stated; electrical conductivity is 1:1 by volume solution mixture unless otherwise stated).

Oase1--0 to 47 centimeters; black (10YR 2/1) broken face and very dark brown (10YR 2/2) rubbed muck; 18 percent fibers, 5 percent rubbed; von Post H8; many fine roots, common very fine roots, and few medium roots; slight sulfurous odor; no color change with 3 percent hydrogen peroxide; slight effervescence with 30 percent hydrogen peroxide; nonsaline (1.4 dS/m); slightly acid (pH 6.4), strongly acid (pH 5.4) oxidized pH; clear boundary.

Oase2--47 to 75 centimeters; very dark grayish brown (2.5Y 3/2) broken face and very dark brown (10YR 2/2) rubbed muck; 20 percent fibers, 8 percent rubbed; von Post H10; common fine roots and few very fine roots; moderate sulfurous odor; no color change with 3 percent hydrogen peroxide; slight effervescence with 30 percent hydrogen peroxide; nonsaline (1.8 dS/m); neutral (pH 6.6), moderately acid (pH 5.6) oxidized pH; clear boundary.

CAseg--75 to 173 centimeters; black (10YR 2/1) loam; structureless, massive; moderately sticky, nonplastic; moderately fluid; few very fine roots; moderate sulfurous odor; color change with 3 percent hydrogen peroxide; slight effervescence with 30 percent hydrogen peroxide; nonsaline (1.2 dS/m); neutral (pH 6.9), extremely acid (pH 4.3) oxidized pH; clear boundary.

Cseg--173 to 200 centimeters; dark gray (10YR 4/1) loam; structureless, massive; slightly sticky, slightly plastic; slightly fluid; no sulfurous odor; no color change with 3 percent hydrogen peroxide; slight effervescence with 30 percent hydrogen peroxide; nonsaline (1.2 dS/m); neutral (pH 7.3), neutral (pH 7.2) oxidized pH.

TYPE LOCATION: City of Virginia Beach, Virginia; in Princess Anne Wildlife Management Area; approximately 3.1 kilometers (1.9 miles) east of the intersection of Princess Anne Road and Public Landing Road, and approximately 5.1 kilometers (3.2 miles) northwest of the intersection of Marsh Causeway and Knotts Island Road (in North Carolina); USGS topographic quadrangle: Knotts Island.

Latitude--36.567136
Longitude-- -75.970759
Datum--WGS84
Coordinate source--From hand-held GPS

RANGE IN CHARACTERISTICS:
Depth to bedrock--Greater than 200 centimeters
Soil moisture regime--Peraquic
Manner of failure / fluidity class--Nonfluid to very fluid throughout the mineral horizons
Wood fragments--0 to 14 percent, by volume
Sulfurous odor--None to strong throughout
Soil reaction--Extremely acid to slightly alkaline in the organic horizons (pH 3.5 to 7.8) and moderately acid to neutral in the mineral horizons (pH 5.6 to 7.3)
Oxidized reaction--Ultra acid to moderately acid in the organic horizons (pH < 3.5 to 6.0) and ultra acid to neutral in the mineral horizons (pH < 3.5 to 7.3).
Depth to hypersulfidic / sulfidic materials (oxidized pH 4.0 or less)--Greater than 100 centimeters
Electrical conductivity (1:1 soil to water solution)--0.6 to 4.7 dS/m throughout
Salinity class--Nonsaline to slightly saline
Total soil organic carbon stock 0 to 100 centimeters--28 to 66 kg m-2
Total soil organic carbon stock 0 to 200 centimeters--37 to 81 kg m-2

Oase horizons:
Hue--5YR to 2.5Y
Value--2 to 3
Chroma--1 to 4
Texture--Muck
Von Post humification scale--H7 to H10
Organic carbon density--24 to 71 kg m-3

Oese or Oise horizons (where present):
Hue--5YR to 10YR
Value--2 to 3
Chroma--1 to 3
Texture--Mucky peat or peat
Von Post humification scale--H4 to H6
Organic carbon density--24 to 71 kg m-3

CAseg, ACseg, or Aseg horizons:
Hue--7.5YR to 10Y
Value--2 to 4
Chroma--1 or 2
Texture--Loam, silt loam, clay loam, silty clay loam, or their mucky analogs
Organic carbon density--25 to 40 kg m-3

Cseg horizons:
Hue--10YR to 10Y, or Neutral
Value--3 to 5
Chroma--0 to 2
Texture--Sandy loam, loam, silt loam, sandy clay loam, clay loam, silty clay loam, or their mucky analogs.
Organic carbon density--17 to 40 kg m-3

COMPETING SERIES:
These are the Delway and Mattan soils.
Delway soils--formed in herbaceous and woody organic materials over fluviomarine deposits and are in estuaries with salinities between 5 and 30 parts per thousand.
Mattan soils--formed in herbaceous and woody organic materials over estuarine deposits, often do not have sulfurous odors or reactions to hydrogen peroxide, and are found in freshwater swamps and marshes along rivers.

GEOGRAPHIC SETTING:
Landscape--Southeast coastal plain estuaries
Landform--Oligohaline marshes on islands, mainland side of barrier-island lagoons, and along rivers
Parent material--Herbaceous organic material over loamy estuarine deposits
Slope--0 to 1 percent
Elevation--0 to 1 meter
Water salinity range--0.5 to 5 parts per thousand
Frost free period--230 to 360 days

GEOGRAPHICALLY ASSOCIATED SOILS:
These are the Backbay, Coinjock, Currituck, Goosecastle, and Pocaty soils.
Backbay soils--are fine-loamy mineral soils with histic epipedons.
Coinjock soils--have organic horizons greater than 130 centimeters thick.
Currituck soils--formed in herbaceous organic materials over sandy marine deposits and are located on or near back barrier tidal marshes
Goosecastle soils--formed in herbaceous organic materials over fluviomarine deposits and contain more hemic material.
Pocaty soils--have organic horizons greater than 130 centimeters thick and contain hypersulfidic materials within 100 centimeters of the soil surface.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--Very poorly drained
Saturated hydraulic conductivity--Moderately low to moderately high
Soil moisture regime--Peraquic
Flooding--The soils are flooded by wind tides. Coratank soils are not normally subject to inundation from lunar tides.

USE AND VEGETATION:
Major uses--Coratank soils are used mainly as wetland wildlife habitat.
Typical vegetation--Dominantly needlegrass rush (Juncus roemerianus), Olney's three square (Schoenoplectus americanus), big cordgrass (Spartina cynosuroides), narrowleaf cattail (Typha angustifolia). Areas transitional to higher elevations have scattered eastern baccharis (Baccharis halimifolia), waxmyrtle (Myrica cerifera), and black willow (Salix nigra) shrubs. In some areas, much of the native vegetation has been overtaken by invasive common reed (Phragmites australis).

DISTRIBUTION AND EXTENT:
General area--Coastal plain estuaries in North Carolina and Virgina
Land Resource Regions--T - Atlantic and Gulf Coast Lowland Forest and Crop Region
MLRA(s)--153B
Extent--Small

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Special Projects Region

SERIES ESTABLISHED: City of Virginia Beach, Virginia, 2026

REMARKS:
The series is named after the Algonquian word for "land of the wild goose". The present-day name of Currituck is derived from Coratank. Coratank soils were previously mapped as the Backbay and Currituck soil series in Virginia and North Carolina, respectively.

Diagnostic horizons and other diagnostic soil characteristics recognized in this pedon are (Keys to Soil Taxonomy, Thirteenth Edition, 2022):
Sapric soil materials--The zone from 0 to 75 centimeters has a fiber content after rubbing that is less than one-sixth of the original soil volume.
Hyposulfidic materials--The zone from 0 to 173 centimeters has an initial pH that decreases by 1 or more units but remains at a value of 4.0 or more after 16 weeks of moist aerobic incubation.
Fluidity--The zone from 75 to 200 centimeters has a fluidity class of slightly fluid to moderately fluid.
Peraquic feature--Zero or positive water potential at or near the soil surface.

NASIS User Site and Pedon ID: S2025VA810105

National Cooperative Soil Survey
U.S.A.