Part 4 - Berg - Hughes Center

1987; Claypool and Mancini, 1989; Mancini et al., 2003, 2005, 2008). Present-day
Smackover microbial and amorphous lime mudstone beds average less than 1% total
organic carbon (Table 1). To adjust for the loss of organic carbon caused by the thermal
maturation process, Li (2006) used the conversion of Daly and Edman (1987). The use of
this conversion indicates that the original total organic carbon in the Smackover was
reduced by 1.5 to 1.8 times during the thermal maturation process. Reservoir rocks
include Upper Jurassic, Cretaceous, and Tertiary continental, coastal, nearshore, marine
shelf, and deep-marine siliciclastics and nearshore marine, shelf, ramp, and reef
carbonates (Mancini et al., 2003, 2008) (Fig. 328 and Table 3). Petroleum seal rocks
consist of Upper Jurassic and Lower Cretaceous anhydrite and shale, Upper Cretaceous
chalk and shale, and lower Tertiary shale (Mancini et al., 2003, 2008) (Fig. 328).
Petroleum traps include structural, stratigraphic, and combination structural-stratigraphic.
Salt related structures are common and consist of pillows and diapers (Hughes, 1968;
Lobao and Pilger, 1985) (Figs. 329-332).
Bossier Petroleum System
Upper Jurassic (Tithonian) to Lower Cretaceous (Berriasian) Bossier shale beds
have been described as source rocks in the East Texas Salt Basin by Ridgley et al. (2006),
and Hermann et al. (1993) reported that gas in the Ruston Field of north Louisiana was
sourced by Cotton Valley shale beds. A preliminary evaluation of the Bossier in the
North Louisiana Salt Basin indicated that these shale beds were possible source rocks in
this basin given the proper organic facies and sufficient total organic carbon contents for
they have experienced the required thermal conditions for thermogenic hydrocarbon
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