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Surface GeologyLehigh Quadrangle, North Dakota
North Dakota Geological Survey24K: Lhgh - sg
Edward C. Murphy, State GeologistLynn D. Helms, Director Dept. of Mineral Resources
102o 37' 30"
46o 52' 30"(BOYLE)
102o 45' 00"
46o 52' 30"
(DICKINSON NORTH)
(SCHEFIE
LD) (LEFOR)
(DIC
KINS
ON SO
UTH)
102o 37' 30"46o 45' 00"
102o 45' 00"46o 45' 00"
(LEFOR NW)
(GLA
DSTO
NE)
Lehigh Quadrangle, North DakotaCartographic Comp ilation: Elroy L. Kadrmas
This g eologic map was funded, in part , by the USGS Natio nal Cooperat ive Geologic Mappin g Prog ram.
MN12o
1959 Magnetic North Declinat ion at Center of Sheet
0 0.5 1Miles
Scale 1:24,000
USGS 7.5 Minu te Topographic Map Contour Interval 10 Feet1927 North American Datum NGVD 192 9
Roads and Hydrolog ic Layers Rectified to 2003 NAIP Digital O rthophoto
Stand ard Parallels 46o 45' 00" and 46o 52' 30"Lambert Co nformal Conic Projection
R. 96 W. R. 95 W.
T. 1 39 N.T. 1 38 N.
RECENT/PLEISTOCENE
Poorly sorted sand, silt, clay, and gravel. Forms planar terrace deposits,elevated relative to modern streams, that are dissected by modern alluvialdeposits. Fluvial (channel and floodplain) sediment generally less than 30feet thick.
Alluvial DepositsQa2
Poorly sorted, iron stained, locally iron cemented sand and gravel. Containspebbles and cobbles of locally derived material (mudstone, sandstone,concretions, silicified wood, flint, silcrete, chalcedony), recycled glacialerratics, and lesser quartzite and porphyry (derived from the Black Hillsor Rocky Mountains). Occasional small to medium boulders or localsandstone and mudstone. Occurs as esker-like ridges, a veneer thatcaps hilltops, and deeply eroded deposits with no distinctive topographicexpression. Fluvial (channel) sediment up to 60 feet thick.
QUATERNARY/TERTIARY SYSTEM
Sand and Gravel DepositsQTa
QUATERNARY SYSTEM
OAHE FORMATION
Sand, silt, and clay depos ited by modern streams and rivers. Gravellywhere derived from coarse, older alluvial deposits . Includes river channeland floodplain sediments. Contains numerous truncated meanders andminor terraces. Local similarity to the Sentinel Butte Formation makesthickness determinations difficult; generally less than 20 feet thick.
Modern Alluvial DepositsQa1
RECENT
Manmade Features or Deposits
Engineered landfill deposits and common garbage dumps .Landfill DepositsQlf
TERTIARY SYSTEM
EOCENE/PALEOCENE
Yellowish brown, micaceous, illitic and montmorillonitic siltstone,claystone, and sandstone.
Camels Butte Member
Bear Den MemberLight gray to bright white kaolinitic strata often divisible into 3 strati-graphic units: basal gray zone, middle orange zone, and a thin uppercarbonaceous zone. Often capped by a silicious bed (Taylor Bed) in this area.
GOLDEN VALLEY FORMATIONTgv
PALEOCENE
FORT UNION GROUP
Gray to brown, variably lithified siltstone, mudstone, claystone, sandstone,and lignite. Calcite-cemented sandstone and mudstone concretions arecommon, as are siderite nodules. In this area, the contact with the GoldenValley Formation appears conformable and gradational. Fluvial, lacustrine,and swamp sediment that form gentle, vegetated slopes. Only the upper200 feet of the formation is exposed.
SENTINEL BUTTE FORMATIONTsb
Other Features
Water
Paved Road
Unpaved Road
Geologic Symbols
Known contact between two geologic units
Approximate contact between two geologic units
Area underlain by abandoned underground lignite mine.
Edward C. Murphy2005
EXPLANATION