Page 290 - Geology of Carbonate Reservoirs

INDEX 271

Cow Creek Formation (Lower Cretaceous) fresh water, 116
Texas, 111 inversion, mineralogical, 159. See also
Crossplots Neomorphism
density–neutron, 202 marine phreatic, 116
porosity–permeability, 194 mechanisms of, 146
Schlumberger M–N, 202 mixing-zone, 116
Cross-cutting relationships neomorphism, 148, 159, 165
in rock properties, 2, 156 recrystallization, 146, 158–159, 170
in thin sections, 156 replacement, 146, 170
Cross sections, structural and stratigraphic, 87 stabilization, neomorphic, 150, 159
Crystal boundaries, compromise, 151 vadose, 116
Crystal forms Diagenetic environments, 9, 224–225
aragonite cements, 148, 167 classification, basis for, 3, 154

calcite cements, 147–148, 167 fresh-water (meteoric) phreatic, 153, 156
dolomite, saddle, 148 marine phreatic, 153
Mg-calcite, 167 mixing zone, 153
Crystal systems of common carbonates, 3 subsurface (burial), 153, 167
Currents vadose, 153, 156, 167
contour, 98, 127 Diagenetic facies, mapping of, 155

density, 98, 122, 127, 130 Dickinson field (Mississippian) North Dakota,
geostrophic, 122, 127, 130 244–249. See also Williston Basin
longshore, 111 Lodgepole Formation (Carboniferous) in,
rip, 111 244
thermohaline (density), 128 Lodgepole mounds in, 245
turbidity, 98, 122, 127 Discoasters, 131. See also Chalk
Cycle skipping, acoustic log, 161, 244 Disconformities, stratigraphic, 101
Cycles, stratigraphic Diversity, taxonomic, 98, 115
“greenhouse and icehouse climates”, infl uence Dolomite, “hydrothermal”, 148
on, 101 Dolomicrites, 26
Milankovich, 101 Dolomitization
origins of, 101 and reservoir porosity, 151–153
order of,101 “excess”, porosity reduction by, 152
shallowing-upward, 28, 102 Drill cuttings, microscopic examination of, 9
Drilling breaks, 161, 193. See also Fractures,

Darcy (laminar) flow, 44, 187 presence in borehole, indirect evidence of
Density, bulk, 31 Dukhan fi eld, Qatar, 191
Depth shifting, core-to-log, 208 Dunes, coastal, 109
Depositional Dysoxia, 98
bodies, typical shapes of, 88
dip, 88 El Abra Formation (Mexico), 46
strike, 88 Enterolithic structures, see Environments, tidal

successions, ideal (standard), 92–93, 96–98, flat and lagoon
106, 203. See also Ideal depositional Environments. See also Ideal depositional
successions and environments successions and environments
Detached abyssal, 98
beach–dune succession, 96, 111 “always wet”, 112
shoreline (barrier island), 82, 111 aphotic, 98
Diachroneity, 80 basinal, 129–133
Diagenesis, 9 bathyal, 98
bioerosion, 146 beach–dune–barrier island, 110–117
cementation, 146, 164, 170 diagenetic, see Diagenetic environments
compaction, mechanical, 146, 164, 170–171 shallow subtidal (neritic), 121–124
deep burial, 146 slope and slope-toe, 126–129
defi nition of, 145 slope-break, 124–126
dissolution, 146, 150 temperate, 81, 112–113, 115
and cave formation, 225 tidal flat and lagoon, 117–121

mesogenetic, 157, 160 tropical, 113