Information Circular 107


southern Escambia County, Alabama (Hughes
Eastern, Alabama permit 4299). Portions of the
shale sequence most likely occur in parts of
Florida as well. However, due to the limited
scope of this project, a thorough study of the
shale lithofacies was not undertaken.
 The most complete section of Norphlet
examined for this study is found in the core from
the Mesa Petroleum well (Florida permit 551)
where 73 feet of continuous Norphlet strata were
examined. The core contains the entire Denkman
Member and a portion of the underlying red bed
sequence. With the exception of a slight
increase in volcanic rock fragments with depth,
the core does not show much vertical variation in
composition. The core consists of interbedded
fine- to medium-grained sandstones in which the
bedding dips range from horizontal to 5, with 10
to 40 dips common.
 At the top of the Mesa core (-16806.5 feet
 below kelly bushing (ft blkb)) is an interval of 7.8
 feet of light-gray, massively bedded, and well-
 cemented sandstone (upper Denkman). Below
 the upper Denkman, the unit changes to a light-
 brown sandstone (lower Denkman) with widely
 spaced, wavy to slightly inclined (10 to 50)
 laminae. At approximately -16837 ft bikb, the
 Denkman grades into red beds.
 An isopach map across panhandle Florida
 shows the variable thicknesses of the formation
 (Figure 4). The average thickness of the unit in
 panhandle Florida is 122.9 feet. However, this
 figure may be misleading since most completely
 penetrated Norphlet sections are believed to lie
 on structural highs (J. Files, Inexco Oil Company,
 1986, personal communication). The Champlin
 Petroleum well (Florida permit 518) exhibits a
 thick section of Norphlet of 410 feet, as
 determined by geophysical log data, whereas the
 Getty Petroleum Company well (Florida permit
 1097) exhibits an abnormally thin section of only
 14.6 feet.

 Denkman Member

 In all cores examined, the Smackover-Norphlet
 contact is relatively sharp, with dense dolomite


overlying quartzose sandstone of the upper
Denkman member. The upper and lower
Denkman cannot be distinguished from one
another by geophysical log characteristics, due
to gross lithologic and sedimentary similarities
(Wilkerson, 1981). However, the two units can
readily be distinguished in hand specimens
where color and sedimentary characteristics
differ. Generally, the Denkman Member is light-
to medium-gray in color at the top and becomes
brown at depth.
 Overall, the upper Denkman is slightly coarser-
grained than the lower Denkman. However, the
average grain size (0.21 mm) of the Denkman
Member is finer than the red bed lithofacies.
Framework packing densities average 79.0
percent. This value indicates a relatively high
framework packing density for panhandle Florida.
Honda (1981) reported an average packing
density of 81.3 percent from the Hatters Pond
Area, Alabama, an abnormally high value.
Extensive pressure solution and grain
rearrangement characterize this high packing
density in Alabama (Honda, 1981), but are not
found extensively in Florida sediments.
 The Denkman Member of panhandle Florida is
 a lithic arkose (Folk, 1980). The average
 composition of framework grains is 61.5 percent
 quartz, 26.3 percent feldspar, and 12.2 percent
 rock fragments. This average composition differs
 slightly from that cited in other studies of the
 region, presumably because all samples used in
 this study are closer to their source areas and
 thus richer in feldspars and lithic grains.


 FRAMEWORK GRAINS

 Quartz is the most abundant detrital mineral in
 the Denkman Member. Quartz content
 throughout the Denkman Member ranges from
 50.5 percent to 75.2 percent, averaging 61.7
 percent of framework grains. The most common
 quartz type present, making up 47.5 percent of
 the total quartz population, is monocrystalline
 quartz with little to no undulatory extinction
 (Figure 5). Some of these grains have mineral