Page 29 - Practical Petroleum Geology, 2nd Edition

stratigraphic, 102–107 sea, 40
structural, 98–102 sediment transport and, 44–46
Petroleum Extension-The University of Texas at Austin
timing and preservation of, 111–112 water drive reservoir, 200, 202, 220
trenches, deep-sea, 21 water front, 202
Triassic period, 23f water saturation, 136, 219
trilobites, 77, 77f water vapor, 17
tubing, 192, 193f, 194, 194f, 195f water-wet reservoirs, 97
turbidite, 59, 59f waves, sediments and, 54–55
turbidity current, 59 weathering
turbulent flow, 44 chemical, 38
two-dimensional seismic data, 116, 120–121, 144 physical, 36–38
sedimentary rock and, 32
wedge-shaped formation, hydrodynamic trapping in,
ultraviolet lights, used to observe cuttings, 174 109f
unconformities, 75–76, 75f, 82, 107, 107f Wegener, Alfred, 19
uniformitarianism, 5–10, 28. See also geologic processes weight-on-bit, 185
United States Geological Survey (USGS), 114 welded tuff, 38, 39f
unitizing drilling units, 155, 155f wells
unproven areas, 149 describing, 205–217
unsaturated hydrocarbons, 84 plugging and abandoning, 150, 204
upfront fees, 152 recovery efficiency, 202–203, 203f
uranium-235, 11, 12f selecting sites, 199–202
uranium-238, 186 well completion
uranyl ion, 186 conventional, 191–195, 193f
U.S. Department of Energy, 158 variations of, 196
U.S. Internal Revenue Code, 159 well inclination, 184
USGS. See United States Geological Survey (USGS) well log data, 113, 129, 129f
well monitoring. See also logging
completing the discovery, 191–197
velocity, measuring, 188 evaluation of production possibilities, 191
vertical cross sections, 142, 142f formation testing, 189–190
vertical migration, 94 geologist’s duties in, 170–173
vertical-cable survey, 126 overview of, 169–170
predicting production, 190
vibrations, protection from, 185 successful wells and, 197–198
Vibroseis, 125, 125f well sites, selecting, 199–202
volcanic arc, 28 well spacing, 155, 158, 200
volcanic ash, 38 wellhead, 147, 150, 159, 194
volcanic rock, 31 wildcat wells, 149
volcanoes during Earth’s formation, 18 wind transport of sediments, 46, 46f. See also aeolian
volumetric calculation, 218–221 deposits
vugs, 106 wireline, 130, 181
wireline formation test, 189
wireline log, 130, 131f, 178, 178f, 179f
water. See also hydrodynamic traps; streams
during Earth’s formation, 18 working interest, 152
flow of, 91–92, 92f World War I, seismographs in, 123–124
petroleum accumulation and, 111
physical weathering and, 37
role in trapping petroleum, 94, 95f, 96, 96f xylene, 85f

284