Information Circular 107


Wiggins Arch probably did not contribute
significantly to deposits in Florida, primarily due
to the downdip location of the arch.
 Neathery and Thomas (1975; Figure 1)
suggested that basement rocks of panhandle
Florida probably are southern extensions of the
Southern Appalachian Piedmont Belt. Dominant
rock types of the Piedmont are mica schist,
granite gneiss, and granite. Evidence for a
Pensacola Arch (Piedmont Belt) source for
Norphlet sediments in panhandle Florida is
provided by the presence of conglomeratic and
red bed lithofacies. Pebble- to cobble-size,
matrix-supported conglomerates are similar to
updip Norphlet conglomerates observed in
southern Alabama wells (Wilkerson, 1981;
Pepper, 1982; Walls, 1985). The restricted updip
distribution of these conglomerates apparently
reflects proximity to, as well as the composition
of, the Pensacola Arch. These conglomerates
are composed dominantly of plutonic and
metamorphic rock fragments.
 Southwestern Alabama red bed lithofacies
 probably represent distal portions of
 conglomeratic sequences (Mancini et al, 1984).
 The locations of Florida red beds, which all lie
 further out into the basin than the conglomerates,
 suggest a Pensacola Arch source for Norphlet
 sediments of panhandle Florida. Supporting
 evidence for this claim is a pronounced fining of
 grain sizes within the quartzose and red bed
 lithofacies toward the center of the Conecuh
 Embayment.
 Evidence for a Conecuh Ridge (Talledega
 Slate Belt) source is less dramatic (Neathery and
 Thomas, 1975; Figure 1). However, higher
 feldspar and sedimentary rock fragment
 concentrations in samples from wells located in
 northern Santa Rosa County may indicate that
 the Conecuh Ridge was a supplier of sediments
 to panhandle Florida.
 Sediments that originated from the Eagle Mills,
 Werner, and Louann Formations also are
 indicated by stratigraphic location and
 composition (Figures 16 and 17). Scott et al,
 (1961) believed the Eagle Mills was initially


deposited in deep, relatively narrow troughs,
bounded by steep faults and cut by volcanic
intrusives. The Conecuh Embayment apparently
lies within one of these troughs (Woods and
Addington, 1973; Figure 3).
 After initial deposition of continental-derived
Eagle Mills sediments within the trough, the
formation was subjected to an extended period of
subaerial weathering (Anderson, 1979).
Following this weathering and subsequent
erosion of some of the Eagle Mills, deposition of
Werner Formation sediments began with these
beds eventually onlapping the paleo-Gulf Coast
(Imlay, 1980). The Werner Formation covered all
of the embayment and apparently much of the
southern end of the Pensacola Arch. The author
believes that the Getty Oil Company well (Florida
permit 1097) lies near the crest of the arch.
Whether the Conecuh Ridge was completely
buried or not by the Werner Formation is unclear.
However, during Werner deposition, updip Eagle
Mills sediments were probably still being shed
and deposited from surrounding highlands. This
can be interpreted from the cross-sections which
shows Eagle Mills sediments capped by lower
Haynesville sediments, indicating exposure of
the Eagle Mills during much of the Jurassic.
Consequently, Eagle Mills sediments were
probably incorporated into lower Werner
sediments (Figures 16 and 17).
 Following Werner Formation deposition,
 deposition of the Louann Formation began within
 the Conecuh Embayment. The Louann
 Formation does not now lie as far inland as the
 Werner Formation, apparently due to post-
 depositional dissolution and erosion of the salt
 during Norphlet deposition. Perhaps the Louann
 originally did overlap the Werner, but it has since
 been eroded back to a more basinward position
 (Anderson, 1979).
 Following the retreat of the Louann Sea from
 the Conecuh Embayment, stream gradients were
 again increased to the point where continental
 erosion could take place (Pepper, 1982). It was
 during this time that Norphlet deposition began.
 Norphlet sediments thus began burying Louann


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