OBJECTID |
MapUnit |
Name |
FullName |
Age |
Description |
HierarchyKey |
ParagraphStyle |
Label |
Symbol |
AreaFillRGB |
AreaFillPatternDescription |
DescriptionSourceID |
GeoMaterial |
GeoMaterialConfidence |
_ID |
1 |
--- |
Quaternary |
--- |
--- |
--- |
1 |
DMUHeading1 |
--- |
--- |
--- |
--- |
OF0330 |
--- |
--- |
DMU01 |
2 |
--- |
Holocene |
--- |
--- |
--- |
1-1 |
DMUHeading2 |
--- |
--- |
--- |
--- |
OF0330 |
--- |
--- |
DMU02 |
3 |
Qal |
Alluvium |
Alluvium |
Quaternary |
Sand, yellow- to brownish-white in color, fine- to coarse-grained, subrounded to rounded, predominately quartzose, locally graveliferous containing aggregate derived from the Pre-loess Terrace deposits, silty to clayey; humus lenses common; floodplain deposits are heavily loess-derived. Silicified wood common. Tributaries have narrow alluvial valleys and are deeply incised through the loess terrain. Thickness is interpreted to be approximately 10 feet with the exception of the Big Black River. |
1-1-1 |
DMUUnit1 |
Qal |
Qal |
255,255,179 |
--- |
OF0330 |
Alluvial sediment, mostly fine-grained |
High |
DMU03 |
5 |
Qtl |
Stream Terrace |
Stream Terrace |
Quaternary |
Flood Plain deposits dominatly associated with the Big Black River; Sand, yellow- to brownish-white in color, fine- to coarse-grained, subrounded to rounded, predominately quartzose, locally graveliferous containing aggregate derived from the Pre-loess Terrace deposits, silty to clayey; humus lenses common; floodplain deposits are heavily loess-derived. Silicified wood common. These terraces are likley locations of pre-historic archeological sites. |
1-1-3 |
DMUUnit1 |
Qtl |
Qtl |
255,255,179 |
Orange Speckled |
OF0330 |
Alluvial sediment, mostly fine-grained |
High |
DMU04 |
6 |
--- |
Pleistocene |
--- |
--- |
--- |
1-2 |
DMUHeading2 |
--- |
--- |
--- |
--- |
OF0330 |
--- |
--- |
DMU05 |
7 |
Ql |
Loess |
Loess |
Pleistocene |
Silt, buff to tan, pale yellow, red, gray to gray-green where in anoxic conditions, quartzose to feldspathic. Loess is considered an eolian deposit derived from glacial outwash. Loess is typically calcareous with dolomite and calcite; however, the upper portion of the loess can be deeply weathered, leached / noncalcareous, and has been commonly referred to as "brown loam." Loess deposits unconformably blanket the pre-loess topography with substantial local variations in thickness but generally thickening towards the west. In places, weathered loess contains secondary deposits of small calcareous concretions (caliche, loess dolls). Loess can be locally and sparingly fossiliferous, commonly containing tests or steinkerns of pulmonate gastropods and less commonly containing fossils of Pleistocene vertebrates. |
1-2-1 |
DMUUnit1 |
Ql |
Ql |
--- |
Hollow Green (38,115,0) Circles overlay all older units |
OF0330 |
Loess |
High |
DMU06 |
8 |
Qtpl |
Pre-loess Terrace Deposits |
Pre-loess Terrace Deposits |
Pleistocene |
Pleistocene ancestral Mississippi River terraces deposited prior to Pleistocene loessification. Sand, yellow, orange, purple, red, pink, fine- to coarse-grained, predominantly quartzose, cross-bedded to massive; graveliferous, pea to large cobble size clasts, boulder size ice-rafted clasts of sandstone and chert. Economically significant gravels are predominantly chert with lesser amounts of vein quartz, metaquartzite, agate, sandstone, and rare rhyolite clasts; clay, pink to white, generally occurring as discontinuous lenses and as rip-up clasts up to boulder-size. Conglomeratic ironstone ledges are common in the graveliferous sands at the base of the deposits. Two distinct terrace levels occur. The first base of this terrace occurs at approximately 220 ft MSL and the second at approximately 270 ft MSL. "Head-of-hollow”, terrace-derived valley-fill deposits are common at lower elevations and are isolated to valley walls adjacent to the erosional remnants of the higher of the two terrace deposits. These deposits are of such limited extent as not to warrant representation on this map. |
1-2-2 |
DMUUnit1 |
Qtpl |
Qtpl |
255,214,230 |
--- |
OF0330 |
Alluvial sediment, mostly coarse-grained |
Low |
DMU07 |
9 |
--- |
Tertiary |
--- |
--- |
--- |
2 |
DMUHeading1 |
--- |
--- |
--- |
--- |
OF0330 |
--- |
--- |
DMU08 |
10 |
--- |
Oligocene |
--- |
--- |
--- |
2-1 |
DMUHeading2 |
--- |
--- |
--- |
--- |
OF0330 |
--- |
--- |
DMU09 |
17 |
Tca |
Catahoula Formation |
Catahoula Formation |
Oligocene |
Deltaic sands, silts, and clays; Sand, gray, pale yellow to white, fine- to coarse-grained, cross-bedded to massive, predominantly quartzose with lesser amounts of chert, metaquartzite, mica, and heavy minerals, slightly glauconitic in places with rare thinly-bedded pea gravels, Gravels, black chert and milky quartz, highly polished, immature, subangular to well rounded; Clay, green, gray, brown, kaolinitic, weathers white to brown exhibiting a "popcorn" appearance, silty to sandy, lignite common in basal clays. Often indurates to opaline-cemented sandstones and rarer orthoquartzites where exposed, silicified wood and fossil palm common. Ironstone common where sands overlie clays. The Catahoula Formation typically unconformably overlies the Bucatunna Formation. However, in the southeast portion of the quadrangle, a basal Catahoula Channel has incised through and eroded much of the underlying Vicksburg Group. Total thickness is approximately 560 feet but full thickness does not occur in this quadrangle. |
2-1-1 |
DMUUnit1 |
Tca |
Tca |
252,89,102 |
--- |
OF0330 |
Sandstone and mudstone |
Low |
DMU10 |
11 |
Tv |
Vicksburg Group |
Vicksburg Group |
Oligocene |
Includes the Bucatunna Formation, Byram Formation, Glendon Limestone, Marianna Limestone, and Mint Spring Formation. The Glendon Limestone is white to gray, commonly indurated to semi-crystalline bioclastic limestone, either massive or with alternating ledges separated by thinly-bedded glauconitic marl. The Glendon Limestone commonly contains solution cavities at or near outcrop. Larger cavities usually form at the contact with the underlying Marianna Limestone. The Marianna Limestone is white to pale-yellow, soft to indurated, glauconitic marl, containing an admixture of fine-grained sands and clays in places. There is an abundance of the large Foraminifera Lepidocyclina mantelli in the Marianna Limestone and Lepidocyclina supera in the Glendon Limestone and the echinoid Clypeaster rogersi. The Vicksburg Limestone unconformably overlies the Forest Hill Formation. Thickness is approximately 100 feet. |
2-1-2 |
DMUUnit1 |
Tv |
Tv |
168,0,0 |
--- |
OF0330 |
Limestone |
Low |
DMU11 |
12 |
Tfh |
Forest Hill Formation |
Forest Hill Formation |
Oligocene |
Deltaic sands, silts, and clays. Sand, fine-grained, silty, quartzose; Clay, carbonaceous, laminated, lignite and silicified wood common. Lignitic plant fossils common along fissile partings in clays. The Forest Hill Formation unconformably overlies the Yazoo Formation. Total thickness is approximately 100 feet. |
2-1-3 |
DMUUnit1 |
Tfh |
Tfh |
191,99,0 |
--- |
OF0330 |
Sandstone and mudstone |
Low |
DMU12 |
13 |
--- |
Eocene |
--- |
--- |
--- |
2-2 |
DMUHeading2 |
--- |
--- |
--- |
--- |
OF0330 |
--- |
--- |
DMU13 |
14 |
Ty |
Yazoo Formation |
Yazoo Formation |
Eocene |
Locally referred to as the Yazoo Clay. Clay, bluish-green to bluish gray, weathers yellowish brown to tan, montmorillonitic, calcareous, silty, locally fossiliferous, locally contains, framboidal pyrite. The Yazoo Formation conformably overlies the Moodys Branch Formation. Total thickness is approximately 500 feet. |
2-2-1 |
DMUUnit1 |
Ty |
Ty |
255,204,0 |
--- |
OF0330 |
Mostly mudstone |
Low |
DMU14 |
15 |
Tmb |
Moodys Branch Formation |
Moodys Branch Formation |
Eocene |
Sandy fossiliferous marl containing an abundance of marine invertebrates typically, Glycymeris and Venericardia shells. Conformably grades into the overlying Yazoo Formation. Total thickness is approximately 15 feet. |
2-2-2 |
DMUUnit1 |
Tmb |
Tmb |
171,107,79 |
--- |
OF0330 |
Mostly mudstone |
Low |
DMU15 |
16 |
Tco |
Cockfield Formation |
Cockfield Formation |
Eocene |
Clay, brown, reddish-brown to grey in color; silty to fine sandy; strongly carbonaceous to lignitic, slightly micaceous, pyritic. Carbonized and silicified plant fossils common.Underlies the Moodys Branch Formation unconformably. |
2-2-3 |
DMUUnit1 |
Tco |
Tco |
237,222,130 |
--- |
OF0330 |
Mostly mudstone |
Low |
DMU16 |