Information Circular 107


the best development of the Brown Dolomite
onshore is in Charlotte and surrounding counties
in the northern part of the South Florida Basin at
a depth of about 12,000 feet. Here, the Brown
Dolomite Zone attains a maximum thickness of
100 feet, of Which about one-half is porous and
capable of high volume fluid production.
Offshore, the maximum thickness occurs near
the Marquesas Keys, where about 400 feet of
mostly porous dolostone has been found. Very
little oil staining has been found in the Charlotte
County area, but staining has been observed in
the Marquesas area, as discussed above.
 Applegate (1987) concluded that the best
possibility for finding oil in the Brown Dolomite
Zone appears to be in the offshore portion of the
South Florida Basin. Brown Dolomite is present
in at least three wells on the Sarasota Arch
(Figure 8) and probably continues around the rim
of the basin southeast to the Marquesas, where
thick porous dolostone is present. Applegate
(1987) believed that stratigraphic and structural
traps associated with this dolostone, which is
capped by dense limestone and anhydrite, may
have led to the formation of giant oil fields.
 In addition to this South Florida Basin
 potential, there has been interest in extending
 Jurassic production in the Florida panhandle
 area. Jurassic production occurs onshore in the
 Jay trend area (Figure 3) from the Smackover
 Formation and Norphlet Sandstone (Figure 4).
 There is also Jurassic production twenty miles to
 the west of the Florida Alabama boundary
 where several natural gas fields produce from
 the Norphlet Sandstone in Alabama state waters
 in Mobile Bay. The Mary Ann gas field was the
 first of these to be discovered in 1979. An
 additional six natural gas fields have been
 established in Alabama state waters since then
 (Masingill, 1989). Recoverable reserves have
 been estimated at 4.93 to 8.12 trillion cubic feet
 of natural gas (Mink, et al., 1987).
 A Jurassic test, the Getty Oil-Florida State
 Lease 2338, Well No. 1 (permit 1097), was
 drilled in 1983 to a total depth of 18,011 feet
 (-17,981 feet MSL) in East Bay, Santa Rosa


County, Florida (Appendix 6, Figure 7). Two
tests in the Smackover Formation produced only
saltwater. The Norphlet Sandstone and
underlying Louann Salt, which together are
responsible for production in the Mobile Bay
fields, were very thin in this well (Applegate and
Lloyd, 1985).
 The three wells drilled off Levy, Citrus, and
Pinellas Counties do not fall within the obvious
target areas discussed above. None of these
wells had significant oil shows or porous zones.
Two of the three penetrated Paleozoic rocks; the
third bottomed in the Lower Cretaceous
(Appendix 6). These may have been drilled with
interest in both the Lower Cretaceous and the
Paleozoic potential. Amoco drilled five Paleozoic
wildcat wells to the north of this area (Taylor,
Madison, Lafayette, and Dixie Counties) in the
early 1980's (Applegate and Lloyd, 1985). All
were dry holes and none had any shows of oil.
Paleozoics in Florida range from Devonian to
Ordovician or Cambrian in age, and are faunally
related to African rocks (Cramer, 1971, 1973).
Production from the West African rocks spurred
interest in Florida; however, the Florida
Paleozoic sandstones are extremely indurated
and have very little porosity or permeability
(Applegate and Lloyd, 1985).


1988 and 1989 Exploratory Drilling in Federal
 Waters, Offshore Florida

 The first federal oil and gas lease sale off
 Florida was conducted in May, 1959 off the
 Florida Keys in what is now the Straits of Florida
 Planning Area. Ten additional OCS lease sales
 have occurred since then; seven in the Eastern
 Gulf of Mexico Planning Area and three in the
 South Atlantic Planning Area. There have been
 no sales in the Straits of Florida Planning Area
 off Florida since the 1959 sale. The last lease
 sale in the South Atlantic Planning Area off
 Florida was Sale 78 in July, 1983.
 The two most recent lease sales off Florida
 were in the Eastern Planning Area. They were