28F; Colquitt Core 10
By Paul Huddlestun
Colquitt 10
Paul Huddlestun
Logged 03/10/1993
Redrawn: 5/31/09
Clay analyses by John Hetrick
COLQUITT 10 (CLARK FARM) GGS-3544 AND
COLQUITT 7 GGS-3213, SAME CORE SITE
COLQUITT COUNTY, GEORGIA
Immediately south of the southern rim of the Gulf Trough;
14.25 airline miles southeast of Colquitt 9a-5-9b
5.8 miles southeast of the center of Moultrie, Georgia: At jct. of
Tallokas Road and Old Berlin Road; 0.5 miles southeast to jct.
Tallokas Road and old Berlin Road; to 0.3 miles southeast to jct.
Old Berlin Road and Culbertson Road; to 0.3 miles northeast
of Culbertson Road to Clark Farm; and 0.2 miles northwest
on Culbertson Road at Clark Farm
Berlin West 7½’ Quadrangle
Latitude N 31° 06.403' Elev. ~270 Feet
Longitude W 83° 44.235'
Immediately south of the southern rim of the Gulf Trough;
14.25 airline miles southeast of Colquitt 9a-5-9b
5.8 miles southeast of the center of Moultrie, Georgia: At jct. of
Tallokas Road and Old Berlin Road; 0.5 miles southeast to jct.
Tallokas Road and old Berlin Road; to 0.3 miles southeast to jct.
Old Berlin Road and Culbertson Road; to 0.3 miles northeast
of Culbertson Road to Clark Farm; and 0.2 miles northwest
on Culbertson Road at Clark Farm
Berlin West 7½’ Quadrangle
Latitude N 31° 06.403' Elev. ~270 Feet
Longitude W 83° 44.235'
14.25 airline miles southeast of Colquitt 9a-5-9b
5.8 miles southeast of the center of Moultrie, Georgia: At jct. of
Tallokas Road and Old Berlin Road; 0.5 miles southeast to jct.
Tallokas Road and old Berlin Road; to 0.3 miles southeast to jct.
Old Berlin Road and Culbertson Road; to 0.3 miles northeast
of Culbertson Road to Clark Farm; and 0.2 miles northwest
on Culbertson Road at Clark Farm
Berlin West 7½’ Quadrangle
Latitude N 31° 06.403' Elev. ~270 Feet
Longitude W 83° 44.235'
SOIL
Bed 1 Sand, medium grained and moderately well 1.5 0.0 sorted; argillaceous; structureless;
unconsolidated but competent; dark yellowish
brown (10 YR 4/2) in color; grades downward
into:
UPPER MIOCENE? PROBABLY TORTONIAN
HAWTHORNE GROUP TRANS. ALTAMAHA FORMATION – 70.5 feet
Bed 2 Sand: medium to fine grained and moderately 6.5 1.5
sorted; argillaceous with clay content
increasing downward, some plinthite nodules;
massive and structureless; unconsolidated but
tough and competent (100% core recovery);
deeply weathered, moderate reddish orange
(10R 6/6); grades downward by increase in
clay content into:
Bed 3 Sand: medium to fine with some fine and 9.0 8.0
coarse grained sand particles, moderately to
moderately poorly sorted, sand-size and
sorting does not appear to change down-
section; very argillaceous with clay content
increasing downward (100% kaolin at 17
feet), a trace of scattered dark minerals,
Massive bedded but the sand distribution is
irregular, occurs in slight concentrations but
the irregularities are not clearly due to
bioturbation;
Bed 1 Sand, medium grained and moderately well 1.5 0.0 sorted; argillaceous; structureless;
unconsolidated but competent; dark yellowish
brown (10 YR 4/2) in color; grades downward
into:
UPPER MIOCENE? PROBABLY TORTONIAN
HAWTHORNE GROUP TRANS. ALTAMAHA FORMATION – 70.5 feet
Bed 2 Sand: medium to fine grained and moderately 6.5 1.5
sorted; argillaceous with clay content
increasing downward, some plinthite nodules;
massive and structureless; unconsolidated but
tough and competent (100% core recovery);
deeply weathered, moderate reddish orange
(10R 6/6); grades downward by increase in
clay content into:
Bed 3 Sand: medium to fine with some fine and 9.0 8.0
coarse grained sand particles, moderately to
moderately poorly sorted, sand-size and
sorting does not appear to change down-
section; very argillaceous with clay content
increasing downward (100% kaolin at 17
feet), a trace of scattered dark minerals,
Massive bedded but the sand distribution is
irregular, occurs in slight concentrations but
the irregularities are not clearly due to
bioturbation;
Bed 4 Sand: mostly as above but more argillaceous 5.0 17.0 and clayey; quartz sand is mostly fine grained,
well sorted and with irregular distribution; a
trace of fine pelletal phosphate appears at 17
feet, a trace to rare dark minerals and a trace
of plinthite; mainly a clayey sand at the base
of the Bed; massive bedded; unconsolidated
but competent (100% core recovery);
weathered but with paler colors, less reds
and more yellows; appears to abruptly overlie:
Bed 5 Very sandy clay/clayey sand: similar to the 10.0 22.0
overlying bed but is even more argillaceous,
the only clay mineral present is kaolin, quartz
sand is mainly fine and well sorted but some
fine to coarse, moderately poorly sorted sand
present in scattered occurrences, a trace of
quartz granules noted; a trace of dark
minerals, still a trace of plinthite (cavings?);
Variably massive bedded to very rudely layered,
sand distribution is irregular with micro- and
macro-lenses of sand, thinly stratified near top
of Bed, very rudely and thinly layered at the
base of the Bed; more clayey intervals display
irregular fracture;
Unconsolidated and moderately competent
(~40% core recovery);
Deeply weathered, color mottles and streaks;
mostly yellowish gray (5Y 8/1) with some pale
red (5R 6/2) and grayish orange (10YR 7/4)
to dark yellowish orange (10YR 6/6);
Grades downward into:
Bed 6 Sand: the recovered sand is fine to coarse, 9.5 32.0
granully and poorly sorted; probably very little
clay, core looks soupy and barely coherent
when recovered; massive and structureless;
basal 1 foot consists of finely sandy, thinly
stratified clay; unconsolidated and moderately
competent (~40% core recovery); colors are the
same as in overlying beds, basal clay is dark
yellowish orange (10YR 6/6); very abruptly
overlies:
Bed 7 Silty fine sand to clay: the upper few inches 20.5 41.5
consisting of waxy clay with fine to very fine,
very well sorted sand interlayered with the clay
appearing below the upper few inches; fine
sand content appears to increase downward
in the recovered core; clayey throughout and
finely micaceous, some dark minerals;
Most of recovered core is disrupted and
appears to have been soft, gummy and gooey
when first recovered but looks originally to
have been thinly layered; rudely and thinly
stratified at the top of the Bed, structureless
in lower part;
Unconsolidated but very poorly coherent and
competent (~10% core recovery);
The color of the uppermost clay layer is closest
to pale red purple (5RP 6/2), patches or minor
interlayering with light bluish gray (5B 7/1) to
very light bluish gray (5B 8/1) and yellowish
gray (5Y 8/1), in the lower part of the Bed the
colors are mainly very pale red purple
(5RP 7/2), very light brownish gray (5YR 7/1)
and grayish orange (10YR 7/4);
Because Bed 7 appears to grade broadly
downward into Bed 8, it is assumed that the
core loss occurred sporadically within the 41.5
feet to 62 feet core run:
Bed 8 Sand: fine to very fine grained, well sorted and 4.0 62.0
argillaceous; the core is disrupted but it
appears the Bed was crudely layered with no
apparent, discrete clay layers; unconsolidated
and mostly competent (~75 % core recovery);
mostly dark yellowish orange (10YR 6/6), the
color grades downward into grayish orange
(10YR 7/4) to dark yellowish orange
(10YR 6/6); grades downward subtly but
abruptly into:
Bed 9 Sandy clay/clayey sand: appears to consist 6.0 66.0
of more clay than sand (67.2% kaolin, 16.9%
illite, 15.9% smectite at 69 feet), common,
minute, tabular clay clasts and irregularly
rounded, moderate sized clay clasts are also
present in the upper part of the Bed; sand
component is fine to very fine grained and
well to very well sorted; rare dark minerals and
what appears to be degraded feldspar grains
noted;
Appears to have been very prominently
layered, laminated, or thinly lenticular but
disrupted due to coring; unconsolidated,
Dense, coherent and mostly competent
(~85% core recovery);
Mostly grayish orange (10YR 7/4), clay
fragments in the upper part of the Bed are
yellowish gray (5Y 7/2), the colors in the
lower part of Bed consist of varying hues of
pale to moderate reddish browns (10R) with
some grayish orange (10YR 7/4), the base of
the Bed is mostly yellowish gray (5Y 8/1)
with some streaks of brownish red (10R);
grades downward into:
Bed 10 Clay: finely sandy with some thin argillaceous 1.5 72.0
sand layers, dark minerals common, some
mica, a possible trace of degraded feldspar;
sand component is fine to very fine grained and
well sorted; prominently bedded although the
core is disrupted; before desiccation, clay
appears to have been gooey and lumpy;
unconsolidated and competent (100% core
recovery); strongly pigmented, pale red purple
(5RP 6/2) to pale red (5R 6/2), some moderate
red (5R 5/4) and light bluish gray (5B 7/1);
very abruptly overlies and with the
appearance of a diastem or disconformity:
well sorted and with irregular distribution; a
trace of fine pelletal phosphate appears at 17
feet, a trace to rare dark minerals and a trace
of plinthite; mainly a clayey sand at the base
of the Bed; massive bedded; unconsolidated
but competent (100% core recovery);
weathered but with paler colors, less reds
and more yellows; appears to abruptly overlie:
Bed 5 Very sandy clay/clayey sand: similar to the 10.0 22.0
overlying bed but is even more argillaceous,
the only clay mineral present is kaolin, quartz
sand is mainly fine and well sorted but some
fine to coarse, moderately poorly sorted sand
present in scattered occurrences, a trace of
quartz granules noted; a trace of dark
minerals, still a trace of plinthite (cavings?);
Variably massive bedded to very rudely layered,
sand distribution is irregular with micro- and
macro-lenses of sand, thinly stratified near top
of Bed, very rudely and thinly layered at the
base of the Bed; more clayey intervals display
irregular fracture;
Unconsolidated and moderately competent
(~40% core recovery);
Deeply weathered, color mottles and streaks;
mostly yellowish gray (5Y 8/1) with some pale
red (5R 6/2) and grayish orange (10YR 7/4)
to dark yellowish orange (10YR 6/6);
Grades downward into:
Bed 6 Sand: the recovered sand is fine to coarse, 9.5 32.0
granully and poorly sorted; probably very little
clay, core looks soupy and barely coherent
when recovered; massive and structureless;
basal 1 foot consists of finely sandy, thinly
stratified clay; unconsolidated and moderately
competent (~40% core recovery); colors are the
same as in overlying beds, basal clay is dark
yellowish orange (10YR 6/6); very abruptly
overlies:
Bed 7 Silty fine sand to clay: the upper few inches 20.5 41.5
consisting of waxy clay with fine to very fine,
very well sorted sand interlayered with the clay
appearing below the upper few inches; fine
sand content appears to increase downward
in the recovered core; clayey throughout and
finely micaceous, some dark minerals;
Most of recovered core is disrupted and
appears to have been soft, gummy and gooey
when first recovered but looks originally to
have been thinly layered; rudely and thinly
stratified at the top of the Bed, structureless
in lower part;
Unconsolidated but very poorly coherent and
competent (~10% core recovery);
The color of the uppermost clay layer is closest
to pale red purple (5RP 6/2), patches or minor
interlayering with light bluish gray (5B 7/1) to
very light bluish gray (5B 8/1) and yellowish
gray (5Y 8/1), in the lower part of the Bed the
colors are mainly very pale red purple
(5RP 7/2), very light brownish gray (5YR 7/1)
and grayish orange (10YR 7/4);
Because Bed 7 appears to grade broadly
downward into Bed 8, it is assumed that the
core loss occurred sporadically within the 41.5
feet to 62 feet core run:
Bed 8 Sand: fine to very fine grained, well sorted and 4.0 62.0
argillaceous; the core is disrupted but it
appears the Bed was crudely layered with no
apparent, discrete clay layers; unconsolidated
and mostly competent (~75 % core recovery);
mostly dark yellowish orange (10YR 6/6), the
color grades downward into grayish orange
(10YR 7/4) to dark yellowish orange
(10YR 6/6); grades downward subtly but
abruptly into:
Bed 9 Sandy clay/clayey sand: appears to consist 6.0 66.0
of more clay than sand (67.2% kaolin, 16.9%
illite, 15.9% smectite at 69 feet), common,
minute, tabular clay clasts and irregularly
rounded, moderate sized clay clasts are also
present in the upper part of the Bed; sand
component is fine to very fine grained and
well to very well sorted; rare dark minerals and
what appears to be degraded feldspar grains
noted;
Appears to have been very prominently
layered, laminated, or thinly lenticular but
disrupted due to coring; unconsolidated,
Dense, coherent and mostly competent
(~85% core recovery);
Mostly grayish orange (10YR 7/4), clay
fragments in the upper part of the Bed are
yellowish gray (5Y 7/2), the colors in the
lower part of Bed consist of varying hues of
pale to moderate reddish browns (10R) with
some grayish orange (10YR 7/4), the base of
the Bed is mostly yellowish gray (5Y 8/1)
with some streaks of brownish red (10R);
grades downward into:
Bed 10 Clay: finely sandy with some thin argillaceous 1.5 72.0
sand layers, dark minerals common, some
mica, a possible trace of degraded feldspar;
sand component is fine to very fine grained and
well sorted; prominently bedded although the
core is disrupted; before desiccation, clay
appears to have been gooey and lumpy;
unconsolidated and competent (100% core
recovery); strongly pigmented, pale red purple
(5RP 6/2) to pale red (5R 6/2), some moderate
red (5R 5/4) and light bluish gray (5B 7/1);
very abruptly overlies and with the
appearance of a diastem or disconformity:
Because there appears to be minute pellets of phosphate in one bed in the upper part of the above section and because the formation is unusually fine grained, the stratigraphic interval above is more compatible with intermediate Altamaha Formation and Hawthorne Group lithologies. Hawthorne Group deposits are marine in origin whereas the Altamaha is fluvial in origin and, normally, the lithologies clearly reflect the differences in environment. I note that the post Meigs section in the Colquitt 9a, 9 miles to the northwest of the Colquitt 10 core site, is likewise not clearly Altamaha in lithology in that it is unusually fine grained. The lithology of the above beds are not assignable to a known formation but may correlate to the Upper Miocene, Ebenezer Formation.
MIDDLE MIOCENE, SERRAVALLIAN
MEIGS FORMATION - 13 feet
Bed 11 Sand: fine grained and well sorted; argillaceous, 2.5 73.5
somewhat micaceous with common dark
minerals, micaceous; small white, chalky
spots that have the appearance of degraded
feldspar or chert; the core is very disrupted but
it looks as though it had been stratified; in
places, the sand appears more finely and thinly
interlensed with clay; unconsolidated, poorly
coherent but competent; less weathered than
overlying beds, pinkish gray (5YR 8/1) in color;
grades abruptly downward into:
Bed 12 Clay and sand: sand and clay are thinly 1.5 76.0
interbedded, interlaminated or interlensed,
clay is the predominant component (59.7%
kaolin, 11.6% illite, 28.6 smectite
at 76 feet), the quartz sand is fine to very fine
grained and well to very well sorted; somewhat
micaceous with common dark minerals, small
white, chalky spots that have the appearance of
degraded feldspar or chert; prominently and
thinly layered to laminated, layering varies from
sharp to crude; unconsolidated, better coherence
and less disruption than overlying beds and
competent; pinkish gray (5YR 8/1) to yellowish
gray (5Y 8/1) to very light orange (10YR 9/2);
grades broadly downward by increase in sand
and less distinct stratification into:
Bed 13 Sand and clay: the quartz sand is fine to very 9.0 77.5
fine grained and well sorted, more sandy and
micaceous in the upper part of the Bed, more
argillaceous (27.7% kaolinite, 16.1% illite, 56.2
smectite at 80 feet) in the middle part of the
Bed with white clasts of cristobolitic claystone
and a thin (1 foot) layer of sand at base of Bed
with reworked clasts of the underlying
formation; a little coarser in the basal few feet;
frequent dark minerals;
Appears massive and structureless but is
variably and vaguely stratified in most
intervals, some bedding disruption due to
coring; unconsolidated and competent, brittle
when desiccated;
Unweathered below 79.5 feet, sandy portion
is yellowish gray (5Y 8/1) to light greenish
gray (5GY 8/1), clay is yellowish gray (5Y 8/1
to 5Y 7/2), basal few feet of sand is yellowish
gray (5Y 7/2) with white (N 9) clasts;
disconformably? overlies:
LOWER MIOCENE, BURDIGALIAN
HAWTHORNE GROUP
MARKS HEAD FORMATION – 46.5 feet
Bed 14 Sand: fine grained and well sorted, sand grains 17.5 86.5
appear frosted (with silica?), probably slightly
siliceous throughout with scattered chert
concretions, white chalky “silica” in the upper
couple feet of the Bed, a thin layer of glassy
“chert” quartzite at ~96 feet; very slightly
argillaceous with some minor concentrations
in some thin intervals (100.0 smectite at 90
feet; 100.0 smectite at 94 feet; 87.9% smectite
and 12.1% sepiolite at 98 feet); common dark
minerals, scattered small irregular shaped
"grains" that are not dark minerals or
carbonaceous material but may be wad
(MnO2) or pyrite;
Mostly massive and structureless but there are
some signs of possibly very vague stratification;
the upper 2 to 3 feet of the bed appears
disrupted prior to deposition of the overlying
bed;
Desiccated sediment is somewhat cemented,
friable and moderately competent (~66% core
recovery);
Color closest to yellowish gray (5Y 8/1) to light
yellowish gray (5Y 9/1), some irregular, small
and minor patches of dark yellowish orange
(10YR 6/6) to grayish orange (10YR 7/4), the
“glassy” sandstone at ~96 feet is light olive
gray (5Y 6/1);
Grades abruptly downward into:
Bed 15 Sand: fine grained and well sorted; very 1.0 104.0
siliceous with chert nodules (has the
appearance of sandy, siliceous, algal mat); no
other lithic components noted; crudely
stratified; partially consolidated and
indurated, competent (100% core recovery);
grades abruptly downward into:
Bed 16 Clay and sand; 2 thin layers of clay with a thin 1.5 105.0
layer of sand sandwiched between; the clay
layers are thinly layered and waxy with some
black material that appears to be wad (MnO2) 15.0 106.5
or black, microcrystalline pyrite stain along
partings; the sand is fine grained, well sorted
and structureless; unconsolidated and
competent; the color range of the clay is
roughly around yellowish gray to pale
yellowish gray (5Y 8/2 to 5Y 9/2); grades
abruptly downward into:
Bed 17 Sand: fine grained and well sorted; clayey with
both interstitial clay and scattered thin clay
layers (17.9% smectite, 38.1% palygorskite,
44.0% sepiolite, at 107 feet; 100.0% smectite
at ~117.0 feet); very but irregularly siliceous,
some relatively pure chert; chert cemented
sandstone (cristobolitic?) at the top of the Bed,
very tough, siliceous (but not chert) sediment
at the base of the Bed;
Mostly massive and structureless with the
appearance of a clay sand with a jumble of
irregular siliceous intraclasts; the lower 2 feet
of the recovered core appears either
bioturbated or intraclastic and massive
bedded;
Mostly unconsolidated and poorly competent
(~32% core recovery);
Color of Bed 17 ranges from close to yellowish
gray (5Y 7/2 - 5Y 8/1)) to pale yellowish
gray (5Y 8/2);
The base of Bed is a thin layer of chert,
appears to abruptly grade downward into:
Bed 18 Sand: fine to very fine grained and well sorted; 11.5 121.5
argillaceous, varying amounts of clay with
more clay in the upper 2 feet of the Bed, (the
clay mineral component consists of 12.6%
illite and 87.4% smectite at 128 feet; 5.5%
illite, 89.8% smectite and 4.7% sepiolite, at
~131 feet); appears to be variably siliceous,
variable quantities of dark minerals, siliceous
at the base of the Bed;
Partly structureless but with some vague to
clear but rude stratification, some apparent
cross bedding in the upper part of the Bed;
Very tough, somewhat consolidated and
mostly competent (~87% core recovery);
The colors of Bed 18 range from yellowish
gray (5Y 7/2 and 5Y 8/1) to pale yellowish
gray (5Y 9/1) to pale olive gray (5Y 6/1);
disconformably overlies:
LOWER MIOCENE, AQUITANIAN
CHATTAHOOCHEE FORMATION – 42 feet
Bed 19 Dolostone: irregularly and finely sandy with 4.0 133.0
what appears to be some sort of scattered
stony algae clasts, clay probably present as a
trace component but none noted; massive and
structureless; mostly recrystallized, mildly
indurated and moderately competent (~40%
core recovery); light olive gray (5Y 6/1) to light
yellowish gray (10Y 9/1) in color; overlies core
gap:
CORE GAP 5.0 137.0
Bed 20 Clay: the clay mineral suite consists of 24.6% 1.0 142.0
illite, 48.5 % smectite and 26.9% palygorskite
at 142.5 feet, dolomitic and finely sandy (more
of a dolomitic “marl”); massive and
structureless; unconsolidated and competent
(100% core recovery); grades abruptly
downward into:
MIDDLE MIOCENE, SERRAVALLIAN
MEIGS FORMATION - 13 feet
Bed 11 Sand: fine grained and well sorted; argillaceous, 2.5 73.5
somewhat micaceous with common dark
minerals, micaceous; small white, chalky
spots that have the appearance of degraded
feldspar or chert; the core is very disrupted but
it looks as though it had been stratified; in
places, the sand appears more finely and thinly
interlensed with clay; unconsolidated, poorly
coherent but competent; less weathered than
overlying beds, pinkish gray (5YR 8/1) in color;
grades abruptly downward into:
Bed 12 Clay and sand: sand and clay are thinly 1.5 76.0
interbedded, interlaminated or interlensed,
clay is the predominant component (59.7%
kaolin, 11.6% illite, 28.6 smectite
at 76 feet), the quartz sand is fine to very fine
grained and well to very well sorted; somewhat
micaceous with common dark minerals, small
white, chalky spots that have the appearance of
degraded feldspar or chert; prominently and
thinly layered to laminated, layering varies from
sharp to crude; unconsolidated, better coherence
and less disruption than overlying beds and
competent; pinkish gray (5YR 8/1) to yellowish
gray (5Y 8/1) to very light orange (10YR 9/2);
grades broadly downward by increase in sand
and less distinct stratification into:
Bed 13 Sand and clay: the quartz sand is fine to very 9.0 77.5
fine grained and well sorted, more sandy and
micaceous in the upper part of the Bed, more
argillaceous (27.7% kaolinite, 16.1% illite, 56.2
smectite at 80 feet) in the middle part of the
Bed with white clasts of cristobolitic claystone
and a thin (1 foot) layer of sand at base of Bed
with reworked clasts of the underlying
formation; a little coarser in the basal few feet;
frequent dark minerals;
Appears massive and structureless but is
variably and vaguely stratified in most
intervals, some bedding disruption due to
coring; unconsolidated and competent, brittle
when desiccated;
Unweathered below 79.5 feet, sandy portion
is yellowish gray (5Y 8/1) to light greenish
gray (5GY 8/1), clay is yellowish gray (5Y 8/1
to 5Y 7/2), basal few feet of sand is yellowish
gray (5Y 7/2) with white (N 9) clasts;
disconformably? overlies:
LOWER MIOCENE, BURDIGALIAN
HAWTHORNE GROUP
MARKS HEAD FORMATION – 46.5 feet
Bed 14 Sand: fine grained and well sorted, sand grains 17.5 86.5
appear frosted (with silica?), probably slightly
siliceous throughout with scattered chert
concretions, white chalky “silica” in the upper
couple feet of the Bed, a thin layer of glassy
“chert” quartzite at ~96 feet; very slightly
argillaceous with some minor concentrations
in some thin intervals (100.0 smectite at 90
feet; 100.0 smectite at 94 feet; 87.9% smectite
and 12.1% sepiolite at 98 feet); common dark
minerals, scattered small irregular shaped
"grains" that are not dark minerals or
carbonaceous material but may be wad
(MnO2) or pyrite;
Mostly massive and structureless but there are
some signs of possibly very vague stratification;
the upper 2 to 3 feet of the bed appears
disrupted prior to deposition of the overlying
bed;
Desiccated sediment is somewhat cemented,
friable and moderately competent (~66% core
recovery);
Color closest to yellowish gray (5Y 8/1) to light
yellowish gray (5Y 9/1), some irregular, small
and minor patches of dark yellowish orange
(10YR 6/6) to grayish orange (10YR 7/4), the
“glassy” sandstone at ~96 feet is light olive
gray (5Y 6/1);
Grades abruptly downward into:
Bed 15 Sand: fine grained and well sorted; very 1.0 104.0
siliceous with chert nodules (has the
appearance of sandy, siliceous, algal mat); no
other lithic components noted; crudely
stratified; partially consolidated and
indurated, competent (100% core recovery);
grades abruptly downward into:
Bed 16 Clay and sand; 2 thin layers of clay with a thin 1.5 105.0
layer of sand sandwiched between; the clay
layers are thinly layered and waxy with some
black material that appears to be wad (MnO2) 15.0 106.5
or black, microcrystalline pyrite stain along
partings; the sand is fine grained, well sorted
and structureless; unconsolidated and
competent; the color range of the clay is
roughly around yellowish gray to pale
yellowish gray (5Y 8/2 to 5Y 9/2); grades
abruptly downward into:
Bed 17 Sand: fine grained and well sorted; clayey with
both interstitial clay and scattered thin clay
layers (17.9% smectite, 38.1% palygorskite,
44.0% sepiolite, at 107 feet; 100.0% smectite
at ~117.0 feet); very but irregularly siliceous,
some relatively pure chert; chert cemented
sandstone (cristobolitic?) at the top of the Bed,
very tough, siliceous (but not chert) sediment
at the base of the Bed;
Mostly massive and structureless with the
appearance of a clay sand with a jumble of
irregular siliceous intraclasts; the lower 2 feet
of the recovered core appears either
bioturbated or intraclastic and massive
bedded;
Mostly unconsolidated and poorly competent
(~32% core recovery);
Color of Bed 17 ranges from close to yellowish
gray (5Y 7/2 - 5Y 8/1)) to pale yellowish
gray (5Y 8/2);
The base of Bed is a thin layer of chert,
appears to abruptly grade downward into:
Bed 18 Sand: fine to very fine grained and well sorted; 11.5 121.5
argillaceous, varying amounts of clay with
more clay in the upper 2 feet of the Bed, (the
clay mineral component consists of 12.6%
illite and 87.4% smectite at 128 feet; 5.5%
illite, 89.8% smectite and 4.7% sepiolite, at
~131 feet); appears to be variably siliceous,
variable quantities of dark minerals, siliceous
at the base of the Bed;
Partly structureless but with some vague to
clear but rude stratification, some apparent
cross bedding in the upper part of the Bed;
Very tough, somewhat consolidated and
mostly competent (~87% core recovery);
The colors of Bed 18 range from yellowish
gray (5Y 7/2 and 5Y 8/1) to pale yellowish
gray (5Y 9/1) to pale olive gray (5Y 6/1);
disconformably overlies:
LOWER MIOCENE, AQUITANIAN
CHATTAHOOCHEE FORMATION – 42 feet
Bed 19 Dolostone: irregularly and finely sandy with 4.0 133.0
what appears to be some sort of scattered
stony algae clasts, clay probably present as a
trace component but none noted; massive and
structureless; mostly recrystallized, mildly
indurated and moderately competent (~40%
core recovery); light olive gray (5Y 6/1) to light
yellowish gray (10Y 9/1) in color; overlies core
gap:
CORE GAP 5.0 137.0
Bed 20 Clay: the clay mineral suite consists of 24.6% 1.0 142.0
illite, 48.5 % smectite and 26.9% palygorskite
at 142.5 feet, dolomitic and finely sandy (more
of a dolomitic “marl”); massive and
structureless; unconsolidated and competent
(100% core recovery); grades abruptly
downward into:
Bed 21 Dolostone: irregular patches of argillaceous, 24.0 143.0
fine sand, and thin, rude layers or
concentrations of dolomitic fine sand; rare
and scattered molds of bivalves (the greatest
concentration is at about ~155 feet), common
algal-like structures but not like the rhodoliths
from the Bridgeboro Limestone; some irregular
patches are argillaceous, the clay mineral suite
consists of 14.0% illite, 70.2% smectite and
15.8% palygorskite at 155 feet; 29.3% illite,
60.0% smectite and 10.7% palygorskite at ~163
feet; scattered MnO2 dendrites; sand and clay
content increases below about 158 feet;
Mostly massive but the sediment is not well
mixed, possibly due to bioturbation or
differential sediment compaction, the Bed is
crudely and more stratified in the lower part,
with some thin layers of dolomitic fine sand
and some very irregular bedding structures;
Partially to mostly recrystallized, mildly
indurated and moderately competent (roughly
62% core recovery);
Mostly yellowish gray (5Y 8/1) in color;
Grades very broadly downward into:
Bed 22 Sand: fine to very fine grained and well sorted; 8.0 167.0
dolomitic, argillaceous (100.0% smectite
at 173 feet); thin, 6 inch thick, hard, dolostone
layers at ~168 feet and at ~170 feet, clay
intraclasts in basal 2.5 feet; the quartz sand is
thin to medium bedded and well stratified;
somewhat consolidated, friable and moderately
competent (~50% core recovery); basal
disconformity is very clear but not sharp, the
underlying Suwannee Limestone was
apparently degraded and the formation’s
contact is marked by a thin clayey layer;
LOWER OLIGOCENE, VICKSBURGIAN
SUWANNEE LIMESTONE – 65 feet+
The composite thickness of the Suwannee
Limestone between the cores Colquitt 10 and
Colquitt 7 is ~136 feet.
Bed 23 Limestone: granular, some chert; no quartz 46.0 175.0
sand or clay minerals noted; microfossiliferous
(foraminifera, ostracods, etc.), only a few
intervals of moldic macrofossils, mostly non-
macrofossiliferous; largely massive and
structureless; variably recrystallized: soft and
porous to dense, crystalline and nonporous
(probably more soft limestone than hard
limestone) variably competent (average core
recovery is ~37%); very pale orange
(10YR 8/2); overlies core gap:
CORE GAP 19.0 221.0
Bottom of the core at 240 feet.
_____________________
TOTAL DEPTH -240.0
fine sand, and thin, rude layers or
concentrations of dolomitic fine sand; rare
and scattered molds of bivalves (the greatest
concentration is at about ~155 feet), common
algal-like structures but not like the rhodoliths
from the Bridgeboro Limestone; some irregular
patches are argillaceous, the clay mineral suite
consists of 14.0% illite, 70.2% smectite and
15.8% palygorskite at 155 feet; 29.3% illite,
60.0% smectite and 10.7% palygorskite at ~163
feet; scattered MnO2 dendrites; sand and clay
content increases below about 158 feet;
Mostly massive but the sediment is not well
mixed, possibly due to bioturbation or
differential sediment compaction, the Bed is
crudely and more stratified in the lower part,
with some thin layers of dolomitic fine sand
and some very irregular bedding structures;
Partially to mostly recrystallized, mildly
indurated and moderately competent (roughly
62% core recovery);
Mostly yellowish gray (5Y 8/1) in color;
Grades very broadly downward into:
Bed 22 Sand: fine to very fine grained and well sorted; 8.0 167.0
dolomitic, argillaceous (100.0% smectite
at 173 feet); thin, 6 inch thick, hard, dolostone
layers at ~168 feet and at ~170 feet, clay
intraclasts in basal 2.5 feet; the quartz sand is
thin to medium bedded and well stratified;
somewhat consolidated, friable and moderately
competent (~50% core recovery); basal
disconformity is very clear but not sharp, the
underlying Suwannee Limestone was
apparently degraded and the formation’s
contact is marked by a thin clayey layer;
LOWER OLIGOCENE, VICKSBURGIAN
SUWANNEE LIMESTONE – 65 feet+
The composite thickness of the Suwannee
Limestone between the cores Colquitt 10 and
Colquitt 7 is ~136 feet.
Bed 23 Limestone: granular, some chert; no quartz 46.0 175.0
sand or clay minerals noted; microfossiliferous
(foraminifera, ostracods, etc.), only a few
intervals of moldic macrofossils, mostly non-
macrofossiliferous; largely massive and
structureless; variably recrystallized: soft and
porous to dense, crystalline and nonporous
(probably more soft limestone than hard
limestone) variably competent (average core
recovery is ~37%); very pale orange
(10YR 8/2); overlies core gap:
CORE GAP 19.0 221.0
Bottom of the core at 240 feet.
_____________________
TOTAL DEPTH -240.0
Paul Huddlestun
Logged ca. 1977
Written up – 10/10/11
U.S. GYPSUM 76-7, GGS-3213,
Same core site as Colquitt 10 (W-3544)
Berlin West 7½’ Quadrangle
Latitude N 31° 06.403’ Elev. 270 Feet
Longitude W 83° 44.235’
Lithostratigraphic
unit and bed number Description Thickness Depth
(feet) (feet)
NO CORE 195.0 0.0
Logged ca. 1977
Written up – 10/10/11
U.S. GYPSUM 76-7, GGS-3213,
Same core site as Colquitt 10 (W-3544)
Berlin West 7½’ Quadrangle
Latitude N 31° 06.403’ Elev. 270 Feet
Longitude W 83° 44.235’
Lithostratigraphic
unit and bed number Description Thickness Depth
(feet) (feet)
NO CORE 195.0 0.0
LOWER OLIGOCENE, VICKSBURGIAN
SUWANNEE LIMESTONE – 116 feet+
Bed 1 Limestone: irregularly hard and soft 14.0 195.0
limestone with the same basic granular/
miliolid texture as Bed 23 in Colquitt 19
core, irregularly scattered mollusk molds
and the calcareous tube, Kuphus
incrassatus at ~200 feet; neither
massive bedded nor layered but irregularly
distributed hard/soft places that appear
to be layers; the soft limestone is porous,
not well indurated and cream in color,
the hard limestone is nonporous and dense
and gray in color; mostly competent (~93%
core recovery); grades downward into:
Bed 2 Limestone: granular foraminiferal/miliolid 12.0 209.0
texture, scattered concentrations of vague
molds of mollusks and inclusions or
intraclasts of softer limestone; mostly
massive and structureless, mostly hard and
recrystallized but there are a few softer
layers within the Bed; mostly competent
(~92% core recovery); grades downward
into:
Bed 3 Limestone: granular foraminiferal/miliolid 3.0 221.0
texture, a few mollusk molds; massive and
structureless; poorly consolidated, almost
soft and moderately competent (~67% core
recovery); abruptly overlies;
Bed 4 Limestone: ghosts of miliolids scattered 2.0 224.0
throughout; massive and structureless; very
hard, dense and competent (100% core
recovery); grades downward into:
Bed 5 Limestone: equigranular, pelletal/ 75.0 226.0
foraminiferal/miliolid limestone; sporadically
macrofossiliferous with rare and scattered
Lepidocyclina, a few scattered mollusk molds,
scattered calcitic shell fragments, locally
abundant stony algae, some solitary corals,
small calcareous tubes (probably vermetids);
mostly massive and structureless except for
some small concentrations of various
macrofossils; variably consolidated and
moderately competent (~42% average core
recovery);
A mold of the gastropod Ampullina? at
~263 feet;
Dictyoconus present from ~295 feet to
~299 feet;
Appears to grade downward into:
Bed 6 Limestone: chalky and fine textured; massive 1.0 301.0
and structureless; poorly consolidated, poor
recovery in the core run that renders the
precise depth of Bed 6 uncertain; overlies
core gap:
CORE GAP 9.0 302.0
LOWER OLIGOCENE, VICKSBURGIAN
BRIDGEBORO LIMESTONE – 77.5 feet±
Glendon-equivalent
Bed 7 Limestone: no lithology recovered – only 6 0.5 311.0
inches worth of stony algal balls;
very poor recovery is typical for coring
in the Bridgeboro Limestone; the hard
rhodoliths act as a ball-mills in grinding
down the softer inter-rhodolith limestone
lithology:
NO RECOVERY 77.0 311.5
UPPER EOCENE, UPPER JACKSONIAN
OCALA GROUP – 472.5 feet
CRYSTAL RIVER LIMESTONE – 437.5 feet
Bed 8 Limestone: a lot of nondescript, granular, 114.5 388.5
calcitic, biofragments/matrix, calcitic
granules range in size from sand-size to
nondescript lumps ~1 cm across;
Lepidocyclina coquina to Lepidocyclina-rich
limestone; most Lepidocyclina are small - a
few mm across and appear to be dominantly
megalosphaeric forms, Asterocyclina is
consistently found below ~405 feet;
scattered molds of mollusks and scattered
calcitic shell fragments, rare oysters and a
trace of Amusium, some stony algal or algal
structures, scattered bryozoans, some
pectenids, vermetids and very rare solitary
corals;
Appears massive bedded except for
the tendency for larger foraminifera and flat
shell fragments to align horizontally; the
limestone generally is porous with porosity
ranging from low porosity where moderately
recrystallized to high porosity in the
Lepidocyclina coquina;
Consolidated and lightly cemented;
moderately and variably competent (~50%
average core recovery);
grades downward into:
Bed 9 Limestone: similar to above but dolomitic 5.0 503.0
with the dolomite content increasing whereas
the fossil content diminishes downward;
broadly transitional with the underlying
bed; grades downward into:
Bed 10 Dolostone: hard, dense and recrystallized, 12.0 508.0
most fossil traces gone in the upper part of
the Bed but some fossil traces evident below
~525 feet; definite rude, horizontal banding
or stratification; recrystallized, indurated
and competent (100% core recovery);
grades downward into:
Bed 11 Limestone: variably chalky – some intervals 9.0 520.0
appear to be more finely equigranular and
sucrosic; variably Lepidocyclina-rich, in
some intervals the Lepidocyclina are
severely corroded, few Lepidocyclina in the
more sucrosic intervals; massive and
structureless; definitely more recrystallized
and altered than Bed 9, competent, core
fractures irregularly; grades downward into:
Bed 12 Limestone: as above but variably dolomitic; 11.5 529.0
some fossil molds still apparent; massive
and structureless; recrystallized and
competent; grades downward into:
Bed 13 Limestone: slightly and variably dolomitic: 6.5 540.5 mostly limestone; sucrosic; fossiliferous but
Lepidocyclina is degraded; massive and
structureless except for a thin layer of
dolostone at ~544 feet; recrystallized and
competent; grades downward into:
Bed 14 Limestone: dolomitic, variable lithology - 19.5 547.0
mostly relatively pure limestone interlayered
variously with some relatively pure dolostone,
dolomitic limestone and calcareous dolostone,
all sucrosic; fossiliferous, Lepidocyclina is
variably corroded; recrystallized and
competent; grades downward into:
Bed 15 Dolostone: fossiliferous but most fossil traces 9.0 566.5 gone; massive and structureless; hard, dense,
recrystallized and competent; grades
downward into:
Bed 16 Dolostone: variably selenitic (top of selenite), 16.5 575.5
selenite occurs interstitially and is a matrix,
dolomite is sucrosic; fossiliferous with
common to abundant Lepidocyclina in
advanced stages of degradation; massive
and structureless; recrystallized and
variably dense, scattered porosity but
selenitic intervals are nonporous,
competent; gray to tan in color; grades
downward into:
Bed 17 Limestone: selenitic, slightly dolomitic and 3.0 592.0
fossiliferous with degraded Lepidocyclina;
massive and structureless, recrystallized,
and competent; grades downward into:
Bed 18 Dolostone: variably selenitic, sucrosic, and 11.0 595.0
fossiliferous with molds of Lepidocyclina
still apparent; massive and structureless,
recrystallized and competent; tan in color;
grades downward into:
Bed 19 Limestone: probably slightly dolomitic, 11.0 606.0
selenite scattered throughout; chalky and
slightly sucrosic, common to abundant
Lepidocyclina in poor states of preservation;
massive and structureless, recrystallized,
competent; grades downward into:
Bed 20 Limestone: dolomitic, selenitic (selenite in 2.0 617.0
optical continuity throughout core);
fossiliferous with severely degraded
Lepidocyclina; massive and structureless;
recrystallized and competent; grades
downward into:
SUWANNEE LIMESTONE – 116 feet+
Bed 1 Limestone: irregularly hard and soft 14.0 195.0
limestone with the same basic granular/
miliolid texture as Bed 23 in Colquitt 19
core, irregularly scattered mollusk molds
and the calcareous tube, Kuphus
incrassatus at ~200 feet; neither
massive bedded nor layered but irregularly
distributed hard/soft places that appear
to be layers; the soft limestone is porous,
not well indurated and cream in color,
the hard limestone is nonporous and dense
and gray in color; mostly competent (~93%
core recovery); grades downward into:
Bed 2 Limestone: granular foraminiferal/miliolid 12.0 209.0
texture, scattered concentrations of vague
molds of mollusks and inclusions or
intraclasts of softer limestone; mostly
massive and structureless, mostly hard and
recrystallized but there are a few softer
layers within the Bed; mostly competent
(~92% core recovery); grades downward
into:
Bed 3 Limestone: granular foraminiferal/miliolid 3.0 221.0
texture, a few mollusk molds; massive and
structureless; poorly consolidated, almost
soft and moderately competent (~67% core
recovery); abruptly overlies;
Bed 4 Limestone: ghosts of miliolids scattered 2.0 224.0
throughout; massive and structureless; very
hard, dense and competent (100% core
recovery); grades downward into:
Bed 5 Limestone: equigranular, pelletal/ 75.0 226.0
foraminiferal/miliolid limestone; sporadically
macrofossiliferous with rare and scattered
Lepidocyclina, a few scattered mollusk molds,
scattered calcitic shell fragments, locally
abundant stony algae, some solitary corals,
small calcareous tubes (probably vermetids);
mostly massive and structureless except for
some small concentrations of various
macrofossils; variably consolidated and
moderately competent (~42% average core
recovery);
A mold of the gastropod Ampullina? at
~263 feet;
Dictyoconus present from ~295 feet to
~299 feet;
Appears to grade downward into:
Bed 6 Limestone: chalky and fine textured; massive 1.0 301.0
and structureless; poorly consolidated, poor
recovery in the core run that renders the
precise depth of Bed 6 uncertain; overlies
core gap:
CORE GAP 9.0 302.0
LOWER OLIGOCENE, VICKSBURGIAN
BRIDGEBORO LIMESTONE – 77.5 feet±
Glendon-equivalent
Bed 7 Limestone: no lithology recovered – only 6 0.5 311.0
inches worth of stony algal balls;
very poor recovery is typical for coring
in the Bridgeboro Limestone; the hard
rhodoliths act as a ball-mills in grinding
down the softer inter-rhodolith limestone
lithology:
NO RECOVERY 77.0 311.5
UPPER EOCENE, UPPER JACKSONIAN
OCALA GROUP – 472.5 feet
CRYSTAL RIVER LIMESTONE – 437.5 feet
Bed 8 Limestone: a lot of nondescript, granular, 114.5 388.5
calcitic, biofragments/matrix, calcitic
granules range in size from sand-size to
nondescript lumps ~1 cm across;
Lepidocyclina coquina to Lepidocyclina-rich
limestone; most Lepidocyclina are small - a
few mm across and appear to be dominantly
megalosphaeric forms, Asterocyclina is
consistently found below ~405 feet;
scattered molds of mollusks and scattered
calcitic shell fragments, rare oysters and a
trace of Amusium, some stony algal or algal
structures, scattered bryozoans, some
pectenids, vermetids and very rare solitary
corals;
Appears massive bedded except for
the tendency for larger foraminifera and flat
shell fragments to align horizontally; the
limestone generally is porous with porosity
ranging from low porosity where moderately
recrystallized to high porosity in the
Lepidocyclina coquina;
Consolidated and lightly cemented;
moderately and variably competent (~50%
average core recovery);
grades downward into:
Bed 9 Limestone: similar to above but dolomitic 5.0 503.0
with the dolomite content increasing whereas
the fossil content diminishes downward;
broadly transitional with the underlying
bed; grades downward into:
Bed 10 Dolostone: hard, dense and recrystallized, 12.0 508.0
most fossil traces gone in the upper part of
the Bed but some fossil traces evident below
~525 feet; definite rude, horizontal banding
or stratification; recrystallized, indurated
and competent (100% core recovery);
grades downward into:
Bed 11 Limestone: variably chalky – some intervals 9.0 520.0
appear to be more finely equigranular and
sucrosic; variably Lepidocyclina-rich, in
some intervals the Lepidocyclina are
severely corroded, few Lepidocyclina in the
more sucrosic intervals; massive and
structureless; definitely more recrystallized
and altered than Bed 9, competent, core
fractures irregularly; grades downward into:
Bed 12 Limestone: as above but variably dolomitic; 11.5 529.0
some fossil molds still apparent; massive
and structureless; recrystallized and
competent; grades downward into:
Bed 13 Limestone: slightly and variably dolomitic: 6.5 540.5 mostly limestone; sucrosic; fossiliferous but
Lepidocyclina is degraded; massive and
structureless except for a thin layer of
dolostone at ~544 feet; recrystallized and
competent; grades downward into:
Bed 14 Limestone: dolomitic, variable lithology - 19.5 547.0
mostly relatively pure limestone interlayered
variously with some relatively pure dolostone,
dolomitic limestone and calcareous dolostone,
all sucrosic; fossiliferous, Lepidocyclina is
variably corroded; recrystallized and
competent; grades downward into:
Bed 15 Dolostone: fossiliferous but most fossil traces 9.0 566.5 gone; massive and structureless; hard, dense,
recrystallized and competent; grades
downward into:
Bed 16 Dolostone: variably selenitic (top of selenite), 16.5 575.5
selenite occurs interstitially and is a matrix,
dolomite is sucrosic; fossiliferous with
common to abundant Lepidocyclina in
advanced stages of degradation; massive
and structureless; recrystallized and
variably dense, scattered porosity but
selenitic intervals are nonporous,
competent; gray to tan in color; grades
downward into:
Bed 17 Limestone: selenitic, slightly dolomitic and 3.0 592.0
fossiliferous with degraded Lepidocyclina;
massive and structureless, recrystallized,
and competent; grades downward into:
Bed 18 Dolostone: variably selenitic, sucrosic, and 11.0 595.0
fossiliferous with molds of Lepidocyclina
still apparent; massive and structureless,
recrystallized and competent; tan in color;
grades downward into:
Bed 19 Limestone: probably slightly dolomitic, 11.0 606.0
selenite scattered throughout; chalky and
slightly sucrosic, common to abundant
Lepidocyclina in poor states of preservation;
massive and structureless, recrystallized,
competent; grades downward into:
Bed 20 Limestone: dolomitic, selenitic (selenite in 2.0 617.0
optical continuity throughout core);
fossiliferous with severely degraded
Lepidocyclina; massive and structureless;
recrystallized and competent; grades
downward into:
Bed 21 Limestone: slightly dolomitic, selenitic, 4.0 619.0
fossiliferous with severely degraded
Lepidocyclina; massive and structureless;
recrystallized, coherent and competent;
grades downward into:
Bed 22 Dolostone: calcareous, selenitic (selenite in 2.0 623.0
optical continuity), fossiliferous with
degraded Lepidocyclina; massive and
structureless; recrystallized and competent;
grades downward into:
Bed 23 Dolostone: selenitic, sucrosic fossiliferous 4.0 625.0
with some Lepidocyclina molds preserved;
massive and structureless; recrystallized,
coherent and competent; tan in color;
grades downward into:
Bed 24 Limestone: very dolomitic, selenitic, fossil 2.0 629.0
Lepidocyclina still visible; massive and
structureless; recrystallized and competent;
grades downward into:
Bed 25 Dolostone: very selenitic with selenite in 7.0 631.0
optical continuity, few Lepidocyclina are
apparent - mostly obliterated; massive and
structureless; recrystallized and competent;
grades downward into:
Bed 26 Limestone: dolomitic, selenitic and more 3.0 638.0
fossiliferous with Lepidocyclina; all else
as above; recrystallized and competent;
grades downward into:
Bed 27 Limestone, as above but slightly dolomitic 3.0 641.0
and less selenitic; fossiliferous with poorly
preserved Lepidocyclina; all else as above;
mostly recrystallized and competent;
grades downward into:
Bed 28 Limestone: sucrosic and chalky, very slightly 20.5 644.0
dolomitic, irregularly scattered and minor
selenite but with consistently scattered
selenite below ~657 feet; very fossiliferous
with abundant Lepidocyclina; massive and
structureless; slightly recrystallized and
competent; white in color; grades downward
into:
Bed 29 Calcareous dolostone/dolomitic limestone 4.0 664.5
(strong HCl reaction but looks like dolostone):
slightly selenitic in the lower part, and
sucrosic; calcitic fossils are chalky and
corroded; massive and structureless;
recrystallized and competent; tan in color;
grades broadly downward into:
Bed 30 Dolostone: selenitic with selenite in optical 2.0 668.5
continuity, fossiliferous but Lepidocyclina is
very degraded; massive and structureless;
recrystallized and competent; gray to tan in
color; grades downward into:
Bed 31 Limestone: chalky, selenitic and a trace of 4.0 670.0
dolomite; Lepidocyclina are common but not
conspicuous; massive and structureless;
recrystallized and competent; white in color;
grades downward into:
Bed 32 Dolostone: selenitic and fossiliferous with 4.0 674.0
degraded Lepidocyclina; massive and
structureless; recrystallized and competent;
white in color; grades downward into:
Bed 33 Limestone: selenitic, very slightly dolomitic 11.0 678.8
and fossiliferous with abundant, degraded
Lepidocyclina; massive and structureless;
recrystallized and competent; grades
downward into:
Bed 34 Dolostone, selenitic and calcareous; sparsely 3.0 689.0 fossiliferous with degraded Lepidocyclina;
massive and structureless; recrystallized
competent; grades downward into:
Bed 35 Dolostone: selenitic with selenite in optical 2.0 693.0
continuity, fossiliferous with severely
degraded Lepidocyclina; massive and
structureless; recrystallized, dense and
competent; tan to gray in color; grades
abruptly downward into:
Bed 36 Limestone: dolomitic, sucrosic, and 3.5 695.0
fossiliferous; massive and structureless;
recrystallized and competent; cream
colored; grades downward into:
Bed 37 Dolostone: calcareous, sucrosic, and 2.5 698.5
fossiliferous; massive and structureless;
recrystallized, indurated and competent;
gray to tan in color; very gradually merges
downward into:
Bed 38 Limestone: very fossiliferous with excellent 104.0 701.0
fossil preservation, bioclastic/pelletal/
granular matrix, no apparent dolomite or
selenite; abundant Lepidocyclina and
bryozoans, Asterocyclina (some large and
multi-rayed) in varying frequencies are
consistently present down the section,
rare Nummulites and Operculinoides,
scattered but conspicuous stony algae
and scattered, locally common Amusium
ocalanum; massive and structureless; well
consolidated and competent but porous
(100% core recovery);
Frequent to common Amusium ocalanum
at ~716 feet;
Stony algae less conspicuous below ~720
feet;
A little more chalky below about ~742 feet;
Asterocyclina frequency diminishes below
~775 feet;
Common Operculinoides around 779 feet;
Lithology becoming less coarsely bioclastic
and becoming granular, sucrosic and chalky
below about 804 feet, grades broadly
downward into:
Bed 39 Limestone: moderately granular, sucrosic, 21.0 805.0
and chalky, variably but only moderately
bioclastic and rubbly in the middle part, but
still sucrosic and chalky; fossiliferous with
common Lepidocyclina throughout; massive
and structureless; moderately recrystallized,
indurated and competent; grades broadly
downward into:
UPPER EOCENE, LOWER JACKSONIAN
OCALA GROUP
WILLISTON LIMESTONE – 35 feet
Bed 40 Limestone: (top of nodular gypsum at 8.5 826.0
~831 feet) grades steadily downward from
overlying bed – mostly intermediate in
lithology from Bed 39 into Bed 41: even
grained, and sucrosic; fossiliferous with
chalky, small and large Lepidocyclina
scattered throughout; dolomitic, selenitic
and with milky, nodular gypsum in the
lower part of the Bed, – nondolomitic
and nongypsiferous in the upper part;
massive and structureless; partially
recrystallized, indurated and competent; grades downward into:
Bed 41 Dolostone: selenitic and fossiliferous 5.5 834.5
massive and structureless; recrystallized
and competent; grades downward into:
Bed 42 Dolomitic selenite/selenitic dolostone: selenite 9.0 840.0 in optical continuity, nodular gypsum at the
base of the Bed; fossiliferous: Lepidocyclina is
conspicuous throughout and appears to have
been replaced at intervals by selenite; massive
and structureless; recrystallized, indurated
and competent (100% core recovery); tan
in color;
Lepidocyclina is chalky from ~847 feet to
848 feet;
About 9 inches of gray, milky, gypsum at ~848
feet with Lepidocyclina still visible within the
gypsum;
Abruptly overlies:
Bed 43 Limestone: dolomitic (active HCl reaction 12.0 849.0
but appears dolomitic), sucrosic with
consistently present milky, nodular gypsum;
fossiliferous with chalky, poorly preserved
larger foraminifera, common Lepidocyclina
and scattered and rare to frequent
Nummulites, common Operculinoides and
Heterostegina in the lower part; massive
and structureless; partially recrystallized,
indurated and competent; tan in color;
First consistent occurrence of Nummulites
at ~850 feet;
First consistent occurrence of nodular
gypsum at ~851 feet;
Operculinoides becoming rare, Heterostegina
and Nummulites more common and
conspicuous in lower 1.5 feet;
Abruptly but apparently gradationally
overlies:
MIDDLE EOCENE; CLAIBORNIAN
UNNAMED CLAIBORNIAN LIMESTONE – 47 feet+
Bed 44 Limestone: dense, chalky, nonfossiliferous 0.5 861.0
and thinly layered; indurated and competent
(100% core recovery); grades downward into:
Bed 45 Limestone: fine textured, somewhat sucrosic 40.0 861.5
and somewhat chalky, selenite and gypsum
nodules are present throughout but more
common in the upper part; dolomite not
apparent;
Variably fossiliferous and conspicuously
fossiliferous at some intervals – more
conspicuously fossiliferous in the more
massive and structureless intervals and,
conversely, less fossiliferous in the layered
intervals; fossiliferous intervals are
dominated by Lepidocyclina, Nummulites,
Operculinoides, Heterostegina and, lower
in the section, Discocyclina; except for
Discocyclina the fossil content does not
vary much throughout (Lepidocyclina is
less conspicuous than in overlying beds),
the more fossiliferous intervals are more
sucrosic, bioclastic and tan in color, the
less fossiliferous, layered intervals are
more chalky and micritic; other
macrofossils such as the mollusks are
conspicuously absent in this Bed;
Variably massive and structureless and
layered to thinly layered; some intervals
appear to be massive and structureless but
the core in those intervals separates along
horizontal partings; the more layered
intervals are finer textured whereas the
more massive intervals are coarser, more
finely bioclastic;
Partially recrystallized, indurated and
mostly competent (~86% core recovery);
buff to tan in color;
Thinly layered from ~863 feet to ~865 feet;
More massive and structureless from ~866
feet to ~873.5 feet; coarser textured, more
bioclastic with conspicuous Lepidocyclina
from ~865 feet to ~868.5 feet;
Gypsum nodules present from ~870.5 feet
to ~872 feet;
Thinly layered from ~873.5 feet to ~875.5
feet with Discocyclina and rare to frequent
Operculinoides and Heterostegina;
Massive and structureless from ~875.5 feet
to roughly 881 feet with common
Lepidocyclina at ~876.5 feet and what
appears to be a chert nodule at ~879 feet;
Consistently thin layering below roughly
~881 feet to total depth of the core with
scattered occurrences of nodular gypsum;
Large Lepidocyclina noted at ~882 feet;
Rare to frequent Discocyclina present from
~886 feet to ~890 feet with a few
Heterostegina, poorly fossiliferous;
Overlies core gap:
CORE GAP 6.5 901.5
Bottom of the core at 908 feet.
___________________________ TOTAL DEPTH – 908 FEET
fossiliferous with severely degraded
Lepidocyclina; massive and structureless;
recrystallized, coherent and competent;
grades downward into:
Bed 22 Dolostone: calcareous, selenitic (selenite in 2.0 623.0
optical continuity), fossiliferous with
degraded Lepidocyclina; massive and
structureless; recrystallized and competent;
grades downward into:
Bed 23 Dolostone: selenitic, sucrosic fossiliferous 4.0 625.0
with some Lepidocyclina molds preserved;
massive and structureless; recrystallized,
coherent and competent; tan in color;
grades downward into:
Bed 24 Limestone: very dolomitic, selenitic, fossil 2.0 629.0
Lepidocyclina still visible; massive and
structureless; recrystallized and competent;
grades downward into:
Bed 25 Dolostone: very selenitic with selenite in 7.0 631.0
optical continuity, few Lepidocyclina are
apparent - mostly obliterated; massive and
structureless; recrystallized and competent;
grades downward into:
Bed 26 Limestone: dolomitic, selenitic and more 3.0 638.0
fossiliferous with Lepidocyclina; all else
as above; recrystallized and competent;
grades downward into:
Bed 27 Limestone, as above but slightly dolomitic 3.0 641.0
and less selenitic; fossiliferous with poorly
preserved Lepidocyclina; all else as above;
mostly recrystallized and competent;
grades downward into:
Bed 28 Limestone: sucrosic and chalky, very slightly 20.5 644.0
dolomitic, irregularly scattered and minor
selenite but with consistently scattered
selenite below ~657 feet; very fossiliferous
with abundant Lepidocyclina; massive and
structureless; slightly recrystallized and
competent; white in color; grades downward
into:
Bed 29 Calcareous dolostone/dolomitic limestone 4.0 664.5
(strong HCl reaction but looks like dolostone):
slightly selenitic in the lower part, and
sucrosic; calcitic fossils are chalky and
corroded; massive and structureless;
recrystallized and competent; tan in color;
grades broadly downward into:
Bed 30 Dolostone: selenitic with selenite in optical 2.0 668.5
continuity, fossiliferous but Lepidocyclina is
very degraded; massive and structureless;
recrystallized and competent; gray to tan in
color; grades downward into:
Bed 31 Limestone: chalky, selenitic and a trace of 4.0 670.0
dolomite; Lepidocyclina are common but not
conspicuous; massive and structureless;
recrystallized and competent; white in color;
grades downward into:
Bed 32 Dolostone: selenitic and fossiliferous with 4.0 674.0
degraded Lepidocyclina; massive and
structureless; recrystallized and competent;
white in color; grades downward into:
Bed 33 Limestone: selenitic, very slightly dolomitic 11.0 678.8
and fossiliferous with abundant, degraded
Lepidocyclina; massive and structureless;
recrystallized and competent; grades
downward into:
Bed 34 Dolostone, selenitic and calcareous; sparsely 3.0 689.0 fossiliferous with degraded Lepidocyclina;
massive and structureless; recrystallized
competent; grades downward into:
Bed 35 Dolostone: selenitic with selenite in optical 2.0 693.0
continuity, fossiliferous with severely
degraded Lepidocyclina; massive and
structureless; recrystallized, dense and
competent; tan to gray in color; grades
abruptly downward into:
Bed 36 Limestone: dolomitic, sucrosic, and 3.5 695.0
fossiliferous; massive and structureless;
recrystallized and competent; cream
colored; grades downward into:
Bed 37 Dolostone: calcareous, sucrosic, and 2.5 698.5
fossiliferous; massive and structureless;
recrystallized, indurated and competent;
gray to tan in color; very gradually merges
downward into:
Bed 38 Limestone: very fossiliferous with excellent 104.0 701.0
fossil preservation, bioclastic/pelletal/
granular matrix, no apparent dolomite or
selenite; abundant Lepidocyclina and
bryozoans, Asterocyclina (some large and
multi-rayed) in varying frequencies are
consistently present down the section,
rare Nummulites and Operculinoides,
scattered but conspicuous stony algae
and scattered, locally common Amusium
ocalanum; massive and structureless; well
consolidated and competent but porous
(100% core recovery);
Frequent to common Amusium ocalanum
at ~716 feet;
Stony algae less conspicuous below ~720
feet;
A little more chalky below about ~742 feet;
Asterocyclina frequency diminishes below
~775 feet;
Common Operculinoides around 779 feet;
Lithology becoming less coarsely bioclastic
and becoming granular, sucrosic and chalky
below about 804 feet, grades broadly
downward into:
Bed 39 Limestone: moderately granular, sucrosic, 21.0 805.0
and chalky, variably but only moderately
bioclastic and rubbly in the middle part, but
still sucrosic and chalky; fossiliferous with
common Lepidocyclina throughout; massive
and structureless; moderately recrystallized,
indurated and competent; grades broadly
downward into:
UPPER EOCENE, LOWER JACKSONIAN
OCALA GROUP
WILLISTON LIMESTONE – 35 feet
Bed 40 Limestone: (top of nodular gypsum at 8.5 826.0
~831 feet) grades steadily downward from
overlying bed – mostly intermediate in
lithology from Bed 39 into Bed 41: even
grained, and sucrosic; fossiliferous with
chalky, small and large Lepidocyclina
scattered throughout; dolomitic, selenitic
and with milky, nodular gypsum in the
lower part of the Bed, – nondolomitic
and nongypsiferous in the upper part;
massive and structureless; partially
recrystallized, indurated and competent; grades downward into:
Bed 41 Dolostone: selenitic and fossiliferous 5.5 834.5
massive and structureless; recrystallized
and competent; grades downward into:
Bed 42 Dolomitic selenite/selenitic dolostone: selenite 9.0 840.0 in optical continuity, nodular gypsum at the
base of the Bed; fossiliferous: Lepidocyclina is
conspicuous throughout and appears to have
been replaced at intervals by selenite; massive
and structureless; recrystallized, indurated
and competent (100% core recovery); tan
in color;
Lepidocyclina is chalky from ~847 feet to
848 feet;
About 9 inches of gray, milky, gypsum at ~848
feet with Lepidocyclina still visible within the
gypsum;
Abruptly overlies:
Bed 43 Limestone: dolomitic (active HCl reaction 12.0 849.0
but appears dolomitic), sucrosic with
consistently present milky, nodular gypsum;
fossiliferous with chalky, poorly preserved
larger foraminifera, common Lepidocyclina
and scattered and rare to frequent
Nummulites, common Operculinoides and
Heterostegina in the lower part; massive
and structureless; partially recrystallized,
indurated and competent; tan in color;
First consistent occurrence of Nummulites
at ~850 feet;
First consistent occurrence of nodular
gypsum at ~851 feet;
Operculinoides becoming rare, Heterostegina
and Nummulites more common and
conspicuous in lower 1.5 feet;
Abruptly but apparently gradationally
overlies:
MIDDLE EOCENE; CLAIBORNIAN
UNNAMED CLAIBORNIAN LIMESTONE – 47 feet+
Bed 44 Limestone: dense, chalky, nonfossiliferous 0.5 861.0
and thinly layered; indurated and competent
(100% core recovery); grades downward into:
Bed 45 Limestone: fine textured, somewhat sucrosic 40.0 861.5
and somewhat chalky, selenite and gypsum
nodules are present throughout but more
common in the upper part; dolomite not
apparent;
Variably fossiliferous and conspicuously
fossiliferous at some intervals – more
conspicuously fossiliferous in the more
massive and structureless intervals and,
conversely, less fossiliferous in the layered
intervals; fossiliferous intervals are
dominated by Lepidocyclina, Nummulites,
Operculinoides, Heterostegina and, lower
in the section, Discocyclina; except for
Discocyclina the fossil content does not
vary much throughout (Lepidocyclina is
less conspicuous than in overlying beds),
the more fossiliferous intervals are more
sucrosic, bioclastic and tan in color, the
less fossiliferous, layered intervals are
more chalky and micritic; other
macrofossils such as the mollusks are
conspicuously absent in this Bed;
Variably massive and structureless and
layered to thinly layered; some intervals
appear to be massive and structureless but
the core in those intervals separates along
horizontal partings; the more layered
intervals are finer textured whereas the
more massive intervals are coarser, more
finely bioclastic;
Partially recrystallized, indurated and
mostly competent (~86% core recovery);
buff to tan in color;
Thinly layered from ~863 feet to ~865 feet;
More massive and structureless from ~866
feet to ~873.5 feet; coarser textured, more
bioclastic with conspicuous Lepidocyclina
from ~865 feet to ~868.5 feet;
Gypsum nodules present from ~870.5 feet
to ~872 feet;
Thinly layered from ~873.5 feet to ~875.5
feet with Discocyclina and rare to frequent
Operculinoides and Heterostegina;
Massive and structureless from ~875.5 feet
to roughly 881 feet with common
Lepidocyclina at ~876.5 feet and what
appears to be a chert nodule at ~879 feet;
Consistently thin layering below roughly
~881 feet to total depth of the core with
scattered occurrences of nodular gypsum;
Large Lepidocyclina noted at ~882 feet;
Rare to frequent Discocyclina present from
~886 feet to ~890 feet with a few
Heterostegina, poorly fossiliferous;
Overlies core gap:
CORE GAP 6.5 901.5
Bottom of the core at 908 feet.
___________________________ TOTAL DEPTH – 908 FEET