DEPARTMENT OF THE INTERIOR
U.S. GEOLOGICAL SURVEY

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° ° = TON, VA—1986— 695188
8 82° ar 80° 79 INTERIOR GEOLOGICAL SURVEY RESTON, VA—1
Base from U.S. Geological Survey SCALE 1:1 000000 Compiled in 1980-81
International Map of the World |IMW Series), 1976 os 5 os so 6. M. Richmond, coordinator
Modified polyconic projection 75 100 MILES
28 25 50 75 100 KILOMETERS
Soe
CONTOURS IN METERS ABOVE MEAN SEA LEVEL
NATIONAL GEODETIC VERTICAL DATUM OF 1923
TENTATIVE CORRELATION OF QUATERNARY AND UPPER PLIOCENE LITHOSTRATIGRAPHIC AND MORPHOSTRATIGRAPHIC UNITS
. . OF THE FLORIDA KEYS AND JACKSONVILLE 4° x 6° QUADRANGLES WITH STRATIGRAPHIC UNITS IN SOUTH CAROLINA é .
125° 120 4 1 96° 0" ae 18° 1 i : nit 8° 80° ue
T —
NORTHERN FLORIDA SUE Oe, NS
FLORIDA KEYS QUADRANGLE
SSA EE CNet DUBAR (19582, 1958b, 1974)
ae SOUTH CAROLINA GEORGIA DUBAR AND OTHERS (1980) ee (1973) J 50'8 STAGES TM. Scott (1)
BUBAR AND OTHERS (1980) COOKE (1943) QAKS AND DUBAR (1974) ‘SHACKLETON AND ys
ee ie \UDDICOAT AND OTHERS (1982) | HOYT AND HAILS (7, 1974) | OSMOND AND OTHERS (1970) irene pe Hes ‘OPDYKE (1973) eee M.S Knapp (1)
MeCARTAN AND OTHERS (1982) | HOYT AND OTHERS (1965) | _PIRKLE AND OTHERS (1963) OSMOND AND OTHERS (1965) oe ore a D L Weide (2) 4
PIRKLE AND YOHO (1970) OSMOND AND OTHERS (1970)
PIRKLE AND CZEL (1983)
PUR! AND VANSTROM (1968)
HOLOCENE 01 1 FLORIDA ATLANTIC OCEAN
SIWVER LF FORMATION Uae TERRACE NED TERRACE Uae FUR MARL 10-21 3
AND TERRACE 254-427 ka ‘SANDS AND SHELL BEDS phe’ a
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87-126 ka FORMATION BS :
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013 i ae SEEDS RUNES NORMAL
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JAMES CITY FORMATION TAAL ROGE FORMATION SEE BRANCH MEMBER 37 POLARITY CHRON z
tee FORMATIONS ‘aN TERRACE ‘SEQUENCE 189-1.79 Ma 24°! 1
1-14 Ma FORT OENAUD MEMBER
¥ ee RESPONSIBILITY FOR STATE COMPILATION
cee OF O.DUVAL NORMAL 1) FLORIDA BUREAU OF GEOLOGY
INDEX TO INTERNATIONAL MAP OF THE WORLD 8/5 Pies bonny vege Suara resides POLARITY SUBCHRON tH UIs GEOLOGICAL SURVEY’
1:1,000,000 TOPOGRAPHIC SERIES = 497-23 Ma AND TERRACE neo Aunt (MARINE FACIES) AT ST. PETERSBURG
Showing location of the Quaternary Geologic Map of the Florida
Keys 4° x 6° Quadrangle in red [U.S. Geological Survey, Miscellaneous « sah pr Lome by Mich
Investigations Series, Map I-1420 (NG-17)] and other published ie Roche
maps in the Quaternary Geologic Atlas of the United States in yellow Ma Million years

QUATERNARY GEOLOGIC MAP OF THE

‘Age ranges suggested by avaiable radiometic ages and paleomagneic data, and may nat be complte

State compilations by

Thomas M. Scott, Michael S. Knapp, and David L. Weide

Edited and integrated by

Gerald M. Richmond, David S. Fullerton, and David L. Weide

1986

QUATERNARY GEOLOGIC ATLAS OF THE UNITED STATES

FLORIDA KEYS 4° x 6° QUADRANGLE, UNITED STATES

PREPARED IN COOPERATION WITH THE
FLORIDA BUREAU OF GEOLOGY

LIST OF MAP UNITS

HOLOCENE
ALLUVIAL CLAY AND SILT

SWAMP DEPOSIT

FRESHWATER MARSH PEAT AND CLAY
PEAT

DRAINED AND COMPACTED PEAT

ALGAL MUD AND CARBONATE

COASTAL MANGROVE SWAMP DEPOSIT
SWAMP DEPOSIT AND DUNE SAND

DUNE SILT AND CLAY

BEACH AND DUNE SAND

BEACH SHELL-FRAGMENT AND SHELL SAND

BEACH MUD

HOLOCENE TO MIDDLE WISCONSIN
LAKE FLIRT MARL

LATE PLEISTOCENE
ANASTASIA FORMATION
MIAMI OOLITE

LATE PLEISTOCENE TO MIDDLE
PLEISTOCENE

BEACH SAND, WEATHERED AND OXIDIZED,
UNDIFFERENTIATED

BEACH SAND AND LAGOONAL DEPOSITS,
UNDIFFERENTIATED

KEY LARGO LIMESTONE

FORT THOMPSON FORMATION

MIDDLE PLEISTOCENE TO EARLY
PLEISTOCENE

BEACH SAND AND SANDY CLAY

EARLY PLEISTOCENE AND PLIOCENE.
CALOOSAHATCHEE MARL
MARINE AND ALLUVIAL SAND

LAND PEBBLE PHOSPHATE DEPOSIT

QUATERNARY AND TERTIARY
SAND AND CLAY DECOMPOSITION RESIDUUM

CALCAREOUS SAND SOLUTION RESIDUUM

BEACH RIDGE—Mapped along Atlantic coast and
discontinuously along central carbonate ridge

NOTE 1: This map is the product of interorganizational
collaboration. Following a regional meeting of state compilers
with the coordinator, during which map units and related matters
were established, a Quaternary map and map explanation of this
quadrangle were prepared by T. M. Scott and M. S. Knapp of the
Florida Bureau of Geology. Supplemental information was
added by D. L. Weide, and G. M. Richmond, editors. Significant
geologic problems requiring changes in the map were resolved in
discussions and by correspondence. Reviewers, to whom the
editors are indebted were W. A. White, University of North
Carolina, and J. B. Cathcart, U.S. Geological Survey.

NOTE 2: The Pliocene-Pleistocene boundary defined by
joint resolution of the International Union for Quatemary
Research (INQUA) Subcommission 1-d on the Pliocene/
Pleistocene Boundary (the International Commission on Stratig-
raphy (ICS) Working Group on the Pliocene/Pleistocene
Boundary) and the Working Group on the International
Geological Correlation Program (IGCP) Project No. 41 (Neogene/
Quaternary Boundary) is that at the Vrica section in southern
Italy. The age of that boundary currently is inferred to be 1.65 Ma
(Aguirre and Pasini, 1984).

Time boundaries between the early Pleistocene and middle
Pleistocene and between the middle Pleistocene and late
Pleistocene are being proposed by the INQUA Working Group
‘on Major Subdivision of the Pleistocene. The boundary between
the early Pleistocene and middle Pleistocene is placed at the
Matuyama-Brunhes magnetic polarity reversal. The reversal has
not been dated directly by radiometric controls. It is significantly
older than the Bishop Tuff (revised K-Ar age 738 ka; Izett, 1982),
and the estimated K-Ar age of 730 ka assigned to the reversal by
Mankinen and Dalrymple (1979) is too young. In Utah, the
Bishop volcanic ash bed overlies a major paleosol developed in
sediments that record the Matuyama-Brunhes reversal (Eardley
and others, 1973). The terrestrial geologic record is compatible
with the astronomical age of 788 ka assigned to the reversal by
Johnson (1982). The boundary between the middle Pleistocene
and late Pleistocene is placed arbitrarily at the beginning of
marine oxygen isotope substage 5e (at Termination II or the
stage 6/5 transition). That boundary also is not dated directly. It
was assigned provisional ages of 127 ka by CLIMAP project
members (CLIMAP Project Members, 1984) and 128 ka by
SPECMAP Project members (Ruddiman and Mcintyre, 1984),
based on uranium-series ages of the substage Se high eustatic
sea level stand. A sidereal age of 132 ka is derived by projection
of the boundary onto the astronomical time scale of Johnson
(1982).

The Pleistocene-Holocene boundary is being proposed by
the INQUA Subcommission on the Holocene. Currently in the
United States, it is placed arbitrarily at 10,000 B.P. (Hopkins,
1975).

Aguirre, Emiliano, and Pasini, Giancarlo, 1984, Proposal of the
ICS Working Group on the Pliocene/Pleistocene boundary
concerning the definition of the Pliocene/Pleistocene
boundary stratotype: 6 p.

CLIMAP Project Members, 1984, The last interglacial ocean:
Quaternary Research, v. 21, p. 123-224.

Eardley, A. J., Shuey, R. T., Gvosdetsky, V., Nash, W. P., Picard,
M. D., Grey, D. C., and Kukla, G. J., 1973, Lake cycles in the
Bonneville Basin, Utah: Geological Society of America
Bulletin, v. 84, no, 1, p. 211-215.

Hopkins, D. M., 1975, Time stratigraphic nomenclature for the
Holocene epoch: Geology, v. 3, no. 1, p. 10.

Izett, G. A., 1982, The Bishop ash bed and some older,
compositionally similar, ash beds in California, Nevada, and
Utah: U.S. Geological Survey Open-File Report 82-582,
47 p., 1 pl.

Johnson, R. G., 1982, Brunhes-Matuyama magnetic reversal
dated at 790,000 yr BP. by marine-astronomical correlations:
Quaternary Research, v. 17, no. 2, p. 135-147.

Mankinen, E. A., and Dalrymple, G. B., 1979, Revised geomag-
netic polarity time scale for the interval 0-5 my. BP:
Journal of Geophysical Research, v. 84, no. B2, p. 615-
626.

Ruddiman, W. F., and McIntyre, A., 1984, Ice-age thermal
response and climatic role of the surface Atlantic Ocean, 40°
N, to 63° N.: Geological Society of America Bulletin, v. 95,
p. 381-396.

QUATERNARY GEOLOGIC ATLAS OF THE UNITED STATES

CORRELATION OF MAP UNITS

wy
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a
BP ez $
a wS<Q 2
BEACH O78 g MARINE
DEPOSITS 4 | DEPOSITS

EOLIAN
DEPOSITS
ALLUVIAL PALUDAL °
DEPOSITS DEPOSITS
—v
acd
DESCRIPTION OF MAP UNITS
HOLOCENE
acd ALLUVIAL CLAY AND SILT—Light- to dark-gray, yellow to

he

brown, poorly to well-stratified, clayey silt and silty clay
alluvium. Deposit contains varying amounts of interbedded
or admixed fine sand, especially in channels along upper
parts of regional drainages. Locally it also includes clay
balls, lenses of kaolinitic clay, and scattered phosphatic
pellets and quartz sand. Mapped areas include organic
muck and swamp deposits (hs) on flood plains and,
locally, colluvium along margins of valley floors. Thickness
generally 5-10 m

SWAMP DEPOSIT—Dark-brown to black muck, mucky peat,
and organic residue mixed with fine to very fine quartz
sand, silt, and kaolinitic clay. Commonly thinly laminated;
locally includes lenses of mottled clay. Large deposits
extensively bioturbated. In topographic depressions,
intermittently covered by 0.5 to 1 m of standing water.
Where these areas have been drained for agriculture,
oxidation of the swamp deposits has resulted in subsidence
as much as 3 m. Small, discontinuous areas of slightly
higher ground are covered with light to dark-brown,
unconsolidated, medium to fine quartz sand. Thickness
310m

FRESHWATER MARSH PEAT AND CLAY—Gray to black
herbaceous peat and clay, intermixed and interbedded.
Color darkens as content of organic matter increases.
Includes interbedded freshwater and brackish-water
deposits. Mapped in part from distribution of freshwater
vegetation. Thickness 1-3 m

PEAT—Dark-gray to black undecomposed to partially de-
composed organic matter compacted into thick mats
interbedded with thin layers of fine sand and silt. Mapped
areas confined to deposits in which volume of organic
matter exceeds that of mineral matter. Thickness 2-5 m

DRAINED AND COMPACTED PEAT—Light- to dark-gray
fibrous peat mixed with other organic material and
interlayered with lenses of silt and fine to medium sand.
Where areas are drained for agriculture and urban
development, burning, oxidation, and compaction of the
deposits has resulted in subsidence of as much as 4 m.
Thickness 2-3 m

ALGAL MUD AND CARBONATE—Blue, green, or gray,
freshwater, algal matte overlying algal calcitic mud
interbedded with thin layers of crystalline low-magnesian
calcite. Deposit forms a rhythmite resulting from annual
growth and death of calcite-secreting blue-green algae
(Gleason, 1972, p. 34-38). Thickness approximately 1 m

COASTAL MANGROVE SWAMP DEPOSIT—Dark-gray to
black organic muck intermittently covered by as much as
1 m of sea water. Overlies wave-beveled surfaces cut on
soft, porous, shelly limestone of late Pleistocene Anastasia
Formation and Tertiary limestone. Mapped only in areas
that support dense stands of both red and black
mangrove along the Gulf of Mexico. Thickness 0.5-1 m

SWAMP DEPOSIT AND DUNE SAND—Swamp deposit is
dark-gray to orange mottled, silty, smectitic clay with
abundant organic debris. Present in parallel, linear,
interdune depressions along Atlantic coast. Dune sand is
white, unconsolidated, and fine to medium grained. It is
composed of quartz mixed with moderate amounts of
shell debris. Deposit forms linear beach and dune ridges
parallel to shore. Dunes are chiefly stabilized by vegetation
though some are locally active. Map unit overlies the
Anastasia Formation in northeast part of the quadrangle.
Deposit is compacted throughout most of eastern
Florida, as a result of drainage for agriculture. Thickness
5-15 m

DUNE SILT AND CLAY—Light-gray to light-yellow, fine to
medium crossbedded sand and sand-size aggregates of
silt and clay particles forming a complex of large dunes.
Mapped only along northeast, east, and southeast shores
of Lake Okeechobee where dunes have accumulated
because of intense storm activity. Thickness 5-10 m

BEACH AND DUNE SAND—Light-tan, angular, medium to
fine sand, well-sorted, crossbedded, mostly quartz with
traces of heavy minerals. Upper layers locally contain
crushed shell that increases gradually in proportion from
north to south. Occurs along coast at and above modern
beach. Also present as thin deposits, too small to map, on
coastal freshwater marsh deposits (hpc). Thickness 2-7 m

BEACH SHELL-FRAGMENT AND SHELL SAND— White to
light-gray shell fragment and shell sand including minor
amounts of fine quartz sand, silt, and clay. Locally the
deposit may be weakly cemented by calcium carbonate.
Where exposed along the Florida Keys, the unit commonly
consists of foraminiferal tests. Thickness 1-5 m

BEACH MUD—Gray to black silt and clay; contains shell
fragments and very fine grained organic matter, color
darkens as amount of organic matter increases. Underlies
beaches bordering saline marsh, estuaries, and lakes
from which it has been transported. Thickness 0.5-1.5 m

HOLOCENE TO MIDDLE WISCONSIN
LAKE FLIRT MARL—Light- to dark-gray freshwater, calcar-
eous fine silt and clay interbedded with soft, white,
freshwater marl and thin layers of organic material, peat,
or muck. Locally may be covered with swamp deposits or
very thin discontinuous patches of quartz and calcareous
sand. Thickness as much as 3 m

LATE PLEISTOCENE

ANASTASIA FORMATION—Present mostly in surbsurface
and shown by pattern on map. Light-gray to yellow,
complexly interbedded, sandy marine limestone, calcar-
eous sandstone and sand; cemented to friable coquina.
Locally contains thin, discontinuous lenses of black silty
muck and decayed organic matter. The Anastasia
Formation is about 110,000 years old as determined by a
Th’*°/U*TM dating method (Osmond and others, 1970).
Exposures of the formation, too small to show at scale of
map, occur discontinuously along the Atlantic coastal
ridge of eastern Florida, but most of unit is covered by
thin swamp deposits (hs) and dune sand (he). Thickness
as much as 30 m

MIAMI OOLITE—White to light-yellow, crystalline, oolitic
limestone interbedded with thin layers of soft, unconsoli-
dated oolitic sand. Locally this unit is perforated with
numerous solution holes and channels now filled with
fine to medium quartz sand. Oolitic limestone portions of
the formation are commonly brecciated and re-cemented
as a result of solution. Th?#°/U25* ages on the Miami
Oolite range from about 90,000 to about 145,000 years
old (Broecker and Thurber, 1965; Osmond and others,
1965). The oolite is exposed at the surface throughout
much of southeast Florida; in places it is covered by thin,
discontinuous patches of eolian oolite and quartz sand
(indicated by pattern). Thickness as much as 20 m

LATE PLEISTOCENE TO MIDDLE PLEISTOCENE
BEACH AND MARINE SAND, WEATHERED AND

mba

MISCELLANEOUS INVESTIGATIONS SERIES
MAP I-1420 (NG-17)

mba

to strongly cemented with calcium carbonate. Basal part
of unit consists of as much as 7 m of consolidated sand
containing abundant whole but rotted bivalve shells.
Deposit overlies sand, clayey sand, or shelly sand of older
Pleistocene beach ridges. Much shell material has been
leached from upper part of the deposits, resulting in
reduction of thickness by as much as 1.5 m. Locally, the
dissolved shell material has been redeposited with
insoluble clay to form a subsurface hardpan. Thickness
6-9 m

BEACH SAND AND LAGOONAL DEPOSITS, UNDIF-

FERENTIATED—Light-gray, yellowish-gray and brownish-
gray, poorly to well-sorted sand, silt, and clay, intermixed
and interbedded. Locally includes thin stringers of well-
rounded quartz pebbles and shell hash in remnants of
old tidal channels. In places, also contains the insoluble
residues of beach sand and sandy lagoonal deposits
associated with older Pleistocene shorelines. Mapped
areas include numerous small swamp deposits (hs),
organic muck, shell debris, and thin patches of eolian
sand. Thickness 10-25 m

KEY LARGO LIMESTONE—Light-gray to light-yellow,

coralline limestone. Highly fossiliferous with molds and
casts of boring marine organisms. Locally composed of
coral heads and algal mounds surrounded by amorphous
limestone, coral detritus, and limestone breccia. Contains
thin lenses of dense, hard, freshwater limestone in places.
Upper surface brecciated and recemented. Th?3°/U234
ages on coral and on oolite are mostly between about
95,000 and 145,000 years (Broecker and Thurber,
1965; Osmond and others, 1965). Maximum thickness
about 20 m

FORT THOMPSON FORMATION—Present only in subsur-

face and shown by pattern on map. White to very light
yellow, sandy limestone and calcareous sandstone,
interbedded with layers and pockets of fine-grained,
well-sorted quartz sand, and thin beds of dense, hard,
freshwater limestone. Exposed in numerous small outcrops
but is mostly covered by thin swamp deposits (hs) and
deposits of weathered and oxidized beach sand (bmk).
Maximum thickness about 25 m

MIDDLE PLEISTOCENE TO EARLY PLEISTOCENE

BEACH SAND AND SANDY CLAY—White, yellow, reddish-

yellow to reddish-orange, well-sorted phosphatic sand
and clayey sand, Locally contains lenses of red to orange-
red, well-sorted, coarse sand stained and cemented with
iron. Deposit reworked from the Pliocene Bone Valley
Formation; in places overlies Tertiary limestone and fills
many of the karst depressions along ridges underlain by
the limestone. Locally overlain by small deposits of white,
very well sorted quartz sand and thin deposits of black to
blue-gray organic muck. Thickness 1-10 m

EARLY PLEISTOCENE AND PLIOCENE

CALOOSAHATCHEE MARL—Present in subsurface only

and shown by pattern on map. Grayish-green or
greenish-gray, silty, sandy marl with interbedded lenses
of sand, silt, and clay. Locally may contain lenses of
carbonaceous material that suggest former mangrove
swamps. West of Lake Okeechobee, consists of a series
of reefs composed of sandy shelly limestone and
calcareous sandstone. Five radiometric dates on corals
from the type locality range from 1.78 Ma (million years)
to 1.89 Ma and average 1.84 Ma; a single date from the
St. Petersburg area is 2.53 Ma (Bender, 1973). All are
older than the estimated age of the Pliocene-Pleistocene
boundary (1.65 Ma). A Pleistocene age is indicated by
the presence of Equus (cf. E.) Leidyi (DuBar, 1958a).
Map unit is overlain by very thin, discontinuous patches
of shelly sand. Maximum thickness 15 m

MARINE AND ALLUVIAL SAND (Facies of Citronelle

Formation)— Upper part is white to light-yellow, fine to
coarse, loose quartz sand, but most of unit is red, orange,
yellow, or brown, crossbedded, pebbly, coarse to fine,
kaolinitic quartz sand, casehardened by iron oxide.
Deposit includes red- and yellow-banded lenses of
generally poorly sorted, slightly kaolinitic, pebbly, coarse
to fine sand, and thin beds of white, highly kaolinitic, well
sorted, fine quartz sand containing numerous shrimp
burrows. Locally includes pockets of white, kaolinitic
clay, and thin stringers of discoid quartz and quartzite
pebbles. Locally deposited on and collapsed into karst
terrain developed on limestone. Coextensive with and
forms an important part of Lake Wales Ridge (Pirkle and
Yoho, 1970), a major topographic feature that forms the
divide of the central Florida peninsula for 250 to 300 km.
Considered in part to be of marine littoral and delta origin
and in part of alluvial origin. Has been correlated with the
Citronelle Formation (Grogan and others, 1964; Pirkle
and Yoho, 1970; White, 1970) which, in its type locality
at Citronelle in Alabama, contains a vertebrate fauna
assigned a Pliocene Hemphillian age by F. C. Whitmore
(Isphording and Lamb, 1971) and fossil leaves of
Pleistocene age (Berry, 1916; Stringfield and Lamoureaux,
1957; Doering, 1958). Thickness 12-15 m

LAND PEBBLE PHOSPHATE DEPOSIT—Present only in

subsurface and shown by pattern on map. Phosphatic
pellets and nodules, quartz sand, and smectitic clay;
chiefly massive and structureless but locally crossbedded
or with horizontal laminations in places. Locally includes
pockets of clay that fill sinkholes in underlying limestone.
Phosphate deposit is believed by Cathcart and others
(1952) to be a residuum derived from underlying
Pliocene Bone Valley Formation; by Sellards (1915) to
have been deposited in a shallow marine environment
following erosion of the Miocene Hawthorn Formation.
Overlain by wave-reworked beach sand and sandy clay
(bm) as thick as 10 m. Thickness as much as 18 m

QUATERNARY AND TERTIARY

Ts | SAND AND CLAY DECOMPOSITION RESIDUUM?—

White, light-yellow, grayish-orange or grayish-red, com-
monly mottled, poorly sorted, fine quartz sand and small
lenses of clay, interbedded with light-gray, yellowish-
gray, very pale orange, or light-reddish-brown, micaceous,
medium to coarse sand; locally includes lenses of
kaolinitic sandy clay that contain leached and partly
decomposed oyster shell fragments. Mapped areas
include some bedrock outcrops and alluvial terrace
deposits too small to map separately, the latter are
formed chiefly on the south side of the mouths of major
rivers flowing into the Gulf of Mexico. Thickness
1-2.5m

[RBI catcareous sanb SOLUTION RESIDUUM'— Yellowish:

gray to grayish-white quartz sand and calcareous sand
residuum on soft sandy limestone and _ shell-hash
limestone. Locally, where deposit mantles an underlying
karst topography, it includes the clay-filling of sink holes.
Mapped areas include some locally derived colluvium,
and scattered bedrock outcrops. Thickness 1-3 m

‘Decomposition residuum, for purpose of this map, is defined as material

OXIDIZED—Light-yellow to dark-orange quartz sand
mixed with and stained by organic matter. Underlain at
depths of as much as to 0.5 m by fine quartz sand
compacted and mixed with insoluble clay; locally, weakly

derived primarily by in-place chemical decay of clastic rock with no appreciable
subsequent lateral transport

2Solution residuum, for purposes of this map, is defined as material
derived by in-place solution of carbonate rock or carbonate-cemented rock
with no appreciable subsequent lateral transport.

RESIDUAL DEPOSITS
———~—_,
DECOM-
POSITION SOLUTION
ay . -
+ Holocene
2
Late
Pleistocene |
\ QUATERNARY
\. Pleistocene
Middle
Pleistocene
Early
J Pleistocene
2
Late Pliocene TERTIARY
Pliocene
if |

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For sale by US. Geological Survey, Map Distribution,
Box 25286, Federal Center, Denver, CO 80225