Part 4 - Berg - Hughes Center

only those wells favorably located with respect to present structure, as well as to structure
during deposition and diagenesis, are productive.
According to Moore and Druckman (1981), the upper Smackover is a blanket ooid
grainstone 300 to 400 ft thick and covering approximately 4,000 sq mi in east Texas,
southern Arkansas and northern Louisiana. Their work in burial diagenesis of the
Smackover indicates that porosity is affected to a greater degree by burial diagenetic
processes than by depositional environment processes. They indicate zones with porosity
values ranging from 11 to 22%, and permeabilities of 1 to 100 millidarcys at the site of
some of the larger upper Smackover discoveries of the 1960s, such as Walker Creek
field, that eventually led to new exploration across the entire Smackover fairway.
Zimmerman’s (1992) study of the sparsely drilled area in the northeast corner of
Louisiana indicates that the extensively fractured intervals observed in Smackover
conventional cores in the area can be attributed to wrench and normal faulting. Although
located on the border of the North Louisiana Salt Basin, this area is an example of
tectonic fracturing that may have future exploration and production potential in the
Smackover interval.
In summary and regarding reservoir conditions of the Smackover in north Louisiana,
depth to pay ranges from 8,600 to 11,600 ft with net pay of producing intervals ranging
from 20 to 120 ft. The oolitic and pisolitic limestones tend to be tight with porosities of
11 to 22% and permeability less than 1 to 100 md. The hydrocarbons produced are
generally 42º to 53º API gravity crudes and condensates.
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