A. Vertical Resolution, Vertical Resolution

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Integrated Reservoir Analysis can be divided into roughly 4 categories: Assembling existing data, Acquiring additional data, Analyzing data, and Integrating data.

2. Geologic data comes from well logs, rock samples, outcrops, maps, cross sections, stratigraphic studies, structural studies, geochemical studies, and petrophysical studies. 3. Geophysical information may include gravity data, magnetic data, and seismic data, as well as 2-D, 3-D, or 4-D surveys, plus vertical seismic profile (VSP) studies, cross-well information, and seismic attribute analysis. 4. Engineering data includes petrophysical, well test, production/injection, pressure, and fluid analysis information, as well as any relevant stress field and fracture data. 5. Logs and cores can offer high ________________ in the reservoir but they are limited by discontinuous sampling. On the other hand, 3-D seismic surveys provide continuous data, but are limited by their lower ___________. a. vertical resolution, vertical resolution b. horizontal resolution, vertical resolution c. vertical resolution, horizontal resolution d. horizontal resolution, horizontal resolution 6. The most essential sources of information for any integrated reservoir characterization project are: a. Logs b. seismic lines c. cores d. produced fluids 7. Reservoir geometry, lithology, structure, and diagenetic history are described by a. geological data b. geophysical data c. engineering data

d. geological and geophysical data e. engineering and geophysical data 8. When used as an engineering tool, production geophysics can help reduce the uncertainty of interwell predictions of reservoir properties by: a. using seismic attributes to predict reservoir properties b. correlating seismic attributes to core data c. correlating seismic attributes to log data d. all of the above 9. The fundamental role for engineers is to characterize and predict fluid flow within the reservoir. To carry out this job, the engineer may use a. 4D seismic data to track fluid flow over time b. petrophysical data to characterize fluid contacts and pathways c. geological maps and facies analysis to find flow barriers d. all of the above 10.

All three disciplines, Geology, Geophysics, and Engineering share

equally in producing the final earth model of the reservoir, but data from each domain brings limitations which introduce a level of uncertainty into the final model. 11. First Drilling in America by using cable tool of 70’ in 1859 at Pennsylvania. 12. Kerosene is first Product used for lamps (Gasoline an unwanted byproduct) 13. Industrial Revolution of Internal Combustion Engine started in 1885. 14. Anticlinal theory (where to drill) was started in 1883. 15. Seismograph invented (remote sensing) in 1914. 16. Establishment of rotary drilling (well control, environment) was in 1920 17. First electrical well logging (formation evaluation) was in 1924 18. Establishment of Offshore drilling (access to prospective areas) was in 1930 19. Establishment of Digital computers (data manipulation) were in 1960s 20. Directional drilling method was developed in 1970. 21. 3D seismic (enhanced imaging) was developed in 1980. 22. Chevron with Gulf Oil established in 1985 (Now Chevron) 23. BP with Amoco established in 1998 (Now BP) 24. Exxon with Mobil established in 1999

25. 26. 27. 28. 29. 30. 31. 32. 33. 34. 35. 36. 37. 38.

Chevron with Texaco established in 2001 (Now Chevron) Conoco with Phillips established in 2002 Conoco with Phillips Merged with Petrofina (Belgium) in 1999 Conoco with Phillips Merged with Elf Aquitaine (France) in 2000 Saudi Aramco petroleum reserves were located in Saudi Arabia. Gazprom petroleum reserves were located in Russia. CNPC petroleum reserves were located in (China) NIOC petroleum reserves were located in (Iran) PDVSA petroleum reserves were located in (Venezuela) Petrobras petroleum reserves were located in (Brazil) Petronas petroleum reserves were located in (Malaysia) Pemex petroleum reserves were located in (Mexico) First off-shore wells were established in 1896 ‘Mudding’ was developed in 1900


First off-shore well built ‘out of sight’ of coast in 1947

40. 41. 42. 43. 44.

API stands for American Petroleum Institute. Light oils are described as being > 40_API heavy oils are < 10_API Mostly oil is > 10_API All carbon are bonded by single bonds with hydrogen so that they

are called as saturated hydrocarbons. 45. Alkanes with < 5 carbons are gas. 46. Alkanes with 5 to 15 carbon atoms are liquids. 47. Alkanes with > 15 carbon atoms are viscous liquids and solids. 48. Composition is based on the benzene ring- Six carbon ring with general formula C6H6. They have a sweet smell- thus named aromatics. 49. Distillation of kerosene from oil was first developed by Canadian geologist Dr. Abraham Gesner. 50. The first refinery was built by the Assam Railway and Trading Company in 1883 at Margherita. 51. The Burniah Shell Company which was formed in January 1928 and the Standard Vacuum Oil (Company (SVOC) which commenced its operations in 13th September 1933 built extensive networks of distribution facilities throughout lndia. 52. Oil and Natural Gas Division was created as a part of the Ministry of Natural Resources & Scientific Research in 1955. 53. A porous and permeable subsurface rock that contains petroleum is called as a Reservoir rock.


A sedimentary rock in which petroleum forms (Generates) is called a

Source rock. 55. Rock Composed of clay and silt-sized particles and fissile is Shale. 56. Carbonates such as coquina are nearly 100% fossil fragments. 57. The rock which can be both as source rock and a cap rock is (Shale) 58. The engineering discipline concerned with the activities related to the production of hydrocarbons, which can be either crude oil or natural gas is (Petroleum Engineering) 59.

The sector of the oil and gas industry, which includes the activities of

finding and producing oil and gas, is called as upstream. 60.

Drilling engineers manage the technical aspects of drilling

exploratory, production and injection wells. It also include mud engineer who manage the quality of drilling fluid. 61.

Reservoir engineers work to optimize production of oil and gas via

proper well placement, production levels, and enhanced oil recovery techniques. 62.

The oil we find underground is called crude oil.


Most commonly, petroleum source rocks containing a minimum of

0.3% to 0.5% by weight of organic matter. 64.

Anaerobic bacteria convert lipids (fat, oil and waxes) into a waxy

substance called kerogen. 65.

Fractional distillation splits the crude oil into simpler mixtures called

fractions. 66.

The barge is a shallow draft, flat-bottom vessel equipped as an

offshore drilling unit, used primarily in swampy areas. 67.

Jack-Up mobile drilling rig is designed to operate in shallow water,

generally less than 500 ft deep. 68.

Piled Steel Platforms are conventional drilling and production

platforms, and hundreds of them are installed offshore in many parts of the world.


Semi-Submersible rigs are floating drilling rigs consisting of hulls or

caissons which carry a number of vertical stabilizing columns and support a deck fitted with a derrick and associated drilling equipment. 70.

The rotary tool that is hung from the hook of the traveling block to

suspend the drillstring and permit it to rotate freely. Swivel 71.

Well log is a continuous record of measurement made in bore hole

respond to variation in some physical properties of rocks through which the bore hole is drilled. 72.

The spontaneous potential (SP) curve records the naturally

occurring electrical potential (voltage) produced by the interaction of formation connate water, conductive drilling fluid, and shale. 73.

The formation density log is a porosity log that measures electron

density of a formation 74.

Resistivity logs measure the ability of rocks to conduct electrical

current. 75.

SPE stands for (Society of Petroleum Engineers)


WPC stands for (World petroleum Congress)


AAPG stands for (American Association of Petroleum Geologists)


Diagenesis is the process by which biopolymer is converted into

geopolymer. 79.

Catagenesis is the process by which geopolymers (Kerogens) are

converted into petroleum. 80.

Oil and gas are found in natural traps within the earth.


The first horizontal wells recorded were drilled in Texon, Texas, in

1929, and Venango County, Pennsylvania, in 1944, 82. A Golden Decade of upstream industry is 1930. 83. The oceanic plates slip under the continental plates, in a process called subduction. 84. Continental plates, forced by convection currents within the Earth, continue today to move away from and back against one another in a process called Divergence.


Where there is an absence of sediments (a break in the continuous

layering) at a particular geographic spot, there is a skip, known as an unconformity, in the sedimentary sequence. 86. Igneous rocks are formed from the bubbling up of the molten material (magma) 87. The most familiar igneous rocks are granite and basalt. 88. Mud is a term that embraces combinations of silt and clay. 89. Typical oil and gas fields are contained in sedimentary rock formations that have porosities ranging from 5% to 30%. 90. A map made at right angles to the surface map is called a cross section or x-section. 91. The geothermal gradient (the rate at which the temperature increases with depth), averages about 15°F per 1,000 feet of depth below the surface. 92. Earth's surface, the ground is relatively dry. It becomes increasingly moist until at some point, called the water table (it becomes 100% water saturated). 93. Normal seawater contains 25,000-35,000 parts per million (ppm) of sodium chloride. 94. Condensate is a very light crude oil-type hydrocarbon that comes from a well producing predominantly natnral gas (a gas well). 95. Heavy crude has little or no natnral gas liquids and a high percentage of the heavy hydrocarbons. 96. °API =(141.5 -;- specificgravity) -131.5 97. Depending on the country, environmental regulations require almost all the sulfur be removed from refined products before they can be sold. 98. A derrick (or mast) that provides a frame from which to raise and lower whatever needs to go in the hole, such as the drill string, casing, or wireline tools. 99. The mud is piped back toward the circulating tanks, but first across a series of vibrating screens called shale shakers 100. Viscosity measures the fluid's resistance to flow 101. Viscosity is measured in centipoises (cp) 102. Pour point measures the lowest temperature at which a crude oil will flow, just before it starts to turn into a solid. 103. The higher the paraffin content of a crude is, the higher will be the pour point.

104. Hydrogen sulfide a lethal gas in very small concentrations, but burning it creates a pollutant. 105. Metals, such as vanadium, nickel, and copper, can damage the catalysts used to process a crude oil in refineries. 106. Two contemporary theories deal with the origin of hydrocarbons, biogenic and abiogenic. 107. The conversion to hydrocarbon began when the temperature rose to about 180°F. 108. The conditions were ideal for oil formation at 7,000-15,000 feet. 109. The conditions were ideal for gas formation at 15,000-25,000 feet. 110. In one version (abiogenic), they allege that hydrocarbon formation took place in the Earth's mantle, 60-180 miles below the surface. 111. Well logging means continuous recording of a physical parameter of the formation with depth. 112. wire line logging are used for the identification of reservoir. 113. Wire line logging is used for the estimation of hydrocarbon in place. 114. Wire

line logging

is used for the estimation of


hydrocarbon. 115. Well logs are results of several geophysical measurements recorded in a well bore. 116. Well logging services are broadly classified into open hole logging, cased hole logging, production logging. 117. Type of Logging operations to be carried out at various rigs is decided based on the requirement of the well. 118. The logging jobs are carried out by truck mounted logging units these units are placed in front of catwalk of the rig. 119. The logging tools are lowered in to the well with the help of logging cable.

120. For lowering the tools with logging cable two sheaves are used. 121. The bottom sheave is tied with derrick floor and placed near the well mouth and the top sheave is hung to the traveling block so that the tools are lowered into the well. 122. The tool is lowered to the desired depth and data is acquired while the tool is pulled up. After completing the survey the Tool is pulled out and rig down process is initiated. 123. Parking of logging unit will be done in front of cat walk. 124. It is also called as the electronic eye of a well. 125. The resistivity of a substance is its ability to impede the flow of electric current through the substance. 126. Formation resistivity is usually fall in the range from 0.2 to 1000 ohm meter. 127. Resistivities higher than 1000 ohm-m are uncommon in permeable formations. 128. There are two types of resistivity Logs. They are Latero logs and Induction logs. 129. In a formation containing oil or gas, both of which are electrical insulators resistivity is a function of formation factor, brine resistivity and water saturation which in term depends on true resistivity. 130. Of the formation parameters resistivity is of particular importance because it is essential for saturation determination mainly of the hydrocarbon. 131. The dual lateral log has been one of primary resistivity measurement device.

132. DLL is designed to minimize influence from borehole fluids and adjacent formations 133. The DLL consists of an electronics section and a mandrel section. 134. The




which are

connected to


electronic circutory. 135. The two measurements by DLL have differing depth of investigation are called deep resistivity (Rd) and shallow resistivity (Rs). 136. DLL consist of a current emitting centre electrode positioned between guard electrodes. 137. Saturation = volume of the porosity occupied by some fluid. 138. SW = water saturation in percent 139. 1 - SW is hydrocarbon saturation in percent. 140. The most frequently used logs are open hole logs. 141. The two primary parameters determined from well log measurements are Porosity, fluid composition and relative saturation. 142. Log interpretations are determined by one of three general types of logs: a. Electrical b. Nuclear c. Acoustic or sonic logs 143. The formations encountered in the bore hole during drilling are invaded to some extent by drilling fluids ("mud") 144. Mud is used to lubricate the bit,

145. Mud is used to circulate the broken rock fragments produced during drilling 146. Mud is used most significantly to maintain pressure in the hole to prevent blow out. 147. The mud invades the formation to at least some degree in order to make useful physical measurements of the insitu rock properties. 148. Steel pipe called "casing" is set in bore holes to prevent damage and caving 149. Only certain down hole tools can make useful measurements through pipe, ie. gamma ray and neutron porosity 150. Decay of radioactive elements produces high energy gamma ray emissions 151. Radioactive elements (K, U, Th) are normally concentrated in shaley rocks while most sandstones are very weakly radioactive. 152. Because radioactive material is concentrated in shale, shale has high gamma ray log readings. 153. Clay-free sandstone and carbonate rocks have low gamma ray log readings 154. Neutron logs (NL or GRN) measure the hydrogen ion concentration in a formation. 155. In



where porosity




water or

hydrocarbons the neutron log measures liquid filled pores (the only significant occurrence of hydrogen). 156. The neutron log measures energy loss when neutrons emitted from the tool collide with other particles in the formation.

157. The maximum energy loss during a neutron collision occurs when a neutron collides with a particle of equal of mass i.e., is a hydrogen atom. 158. A lower neutron log reading (fewer energetic back scattered neutrons) indicates abundant formation hydrogen. 159. Clay rich formations contain hydrogen in the crystal structure of the clay minerals and give anomalous values for liquid filled pore volume. 160. Neutron log excursions (decreasing in value from right to left) indicate higher proportions of hydrogen in the Formation. 161. Neutron log excursions increasing from left to right indicate less porosity and/or less shale 162. Newer “radiation” logs called CNL (for compensated neutron logs) are calibrated so that the scale is in porosity units, or neutron porosity units 163. The CNL sometimes called the NPHI, for Neutron porosity {φ} 164. The formation density log and these logs, in combination, can be used to infer lithology 165. Formation density (compensated; FDC) logs measure the density (grams/cm3) of the formation based on the density of electrons in the formation 166. Electron density is a function of the absolute amount of matter comprising the formation 167. Electron density is measured by the back scatter of gamma rays emitted from a gamma ray source in the logging tool

168. The absolute amount of matter in the formation is inversely proportional to the degree of gamma ray penetration into the formation without back scatter to the detector 169. Bulk density is read on a log increasing from left to right. 170. An industry standard "quick-look" overlay methodology can be used with CNL-FDC wire-line logs 171. When Neutron porosity (CNL dashed curve) and Bulk Density (FDC, solid curve) logs are overlain on a common, limestone equivalent porosity scale changes in lithology can be inferred with depth 172. The logged value is a direct function of the aggregate atomic number (Z) of the elements in the formation, and so is a sensitive indicator of mineralogy. 173. Electric logs, resistivity and spontaneous potential, were the first wireline logging tools. 174. Electrical current generated across the boundary between inter bedded shale and sandstone. 175. The spontaneous potential associated with shale and sandstones is the result









permeability in shale. 176. For oil, total oil in place (in barrels) N= (1- Sw) x porosity x A x h x Bo x 7,758 177. for gas, the total gas in place (in cubic feet) G = (1- Sw) x porosity x A x h x (11Bg) x 43,560 178. Water saturation, SW> is 15% determined by examination of the resistivity from induction logs.

179. Porosity is about 25% (0.25) determined by examination of cores and/or a combination of density, neutron, or sonic logs. 180. The drainage area (the productive area), obtained from the geologist's maps, equals to about 250 acres. 181. The net pay thickness found from the gamma ray or SP logs. 182. The oil shrinkage factor is assumed, on the basis of experience and laboratory work with oils common to the area, to be 0.6. 183. The DST assembly consists of a valve, a packer, and a pressure recorder, with a section of perforated pipe at the bottom, through which formation fluids can flow. 184. The driller runs the drill string to the bottom of the hole with the valve closed. 185. The pressure recorder, located below the closed valve. 186. The pressure recorder, records the increasing weight of the column of mud above it (the hydrostatic pressure), on the outside of the drill string, as it goes down the hole. 187. When the DST assembly reaches total depth (TD), the driller lets a small amount of weight rest on the tool. 188. If the permeability is high, the formation pressure is reached very quickly; 189. If the permeability is low, a true reading of the formation pressure may not be obtained. 190. The recorded pressure at pressure recorder is called the initial shutin pressure. 191. Drillers become nervous whenever pipe is in the hole, not moving-and especially when there is no circulating mud flow. 192. At an onshore operation, oil is directed to a storage pit specially dug for the purpose. 193. Gas is sent down a pipe, away from the rig, and ignited, an operation called flaring. 194. Some hydrocarbons could even invade and pollute aquifers at higher levels. 195. Production casing is run and cemerited inside whatever strings of casing were used to drill to TD.

196. After the production casing (the last casing string) has been cemented, a wellhead is installed. 197. The production tubing is run through the wellhead and secured by a tubing hanger. 198. The surface controlling valves are bolted to the top of the wellhead. 199. If the combination of surface controls is more elaborate, the assembly is often called a Christmas tree. 200. Wells drilled offshore can be connected to either of two types of trees: dry trees & wet trees. 201. A portable derrick that can be raised as unit. 202.

For transporting by land, the mast can be divided into two or more

sections. 203. A large load bearing structure, usually of bolted construction. 204. The standard derrick has four legs standing at the corners of the substructure. 205. Internal combustion engine or a turbine that is the source of power for driving equipment on the Rig. 206. Drawworks is essentially a winch that spools off or takes in the drilling line and thus raises or lowers the drillstring. 207. Crown Block is an assembly of sheaves mounted on beams at the top of the derrick/mast and over which the drilling line is reeved. 208. An assembly of sheaves or pulleys through which the drilling line is reeved and which moves up and down in the Derrick or Mast.( Traveling Block) 209. An equipment that holds down the deadline part of the wire rope (Deadline Anchor) 210. The rotary tool that is hung from the hook of the traveling block to suspend the drillstring and permit it to rotate freely. Swivel

211. Kelly has a bored passageway that permits fluid to be circulated into the drill stem and up the annulus or vice versa. 212. A hydraulically powered device located below the Swivel that when actuated allows the Drillstem to spin and proceed in drilling.(Top Drive) 213. Equipment used to turn the drill stem and support the drilling assembly.( Rotary Table) 214. The Rig Equipment responsible the movement of drilling fluid within the well as well as solids removal incurred by the drilling fluid. (Circulating Component) 215. A typical mud pump is a two cylinder, double acting or a three-cylinder, single acting piston pump whose pistons travel in replaceable liners and are driven by a crankshaft actuated by an engine or motor. 216. An equipment the uses a vibrating screen to remove cuttings from the circulating fluid in rotary drilling operations.(Shale Shaker) 217. A centrifugal device for removing sand from the drilling fluid to prevent abrasion of the pumps.(Desander) 218. A centrifugal device for removing free particles of silt from the drilling fluid to keep the amount of solids in the fluid at the lowest possible point. ( Desilter ) 219. The Rig Equipment responsible for preventing the buildup of unwanted formation fluids that lead to Blowout.( Blowout Preventer) 220. A well no longer in use; a dry hole that, in most jurisdictions, must be properly plugged is called (ABANDONED WELL). 221. A magnetic survey, made from an aircraft is called AEROMAGNETIC SURVEY.

222. A seismic signal source which utilizes compressed air to create a sonic wave is AIR GUN. 223. The annular space between the drill pipe and the well bore. ANNULUS 224. A subsurface geological structure in the form of a gentle arch or an elongated dome is ANTICLINE. 225. Wells drilled in the vicinity of a discovery or wildcat well in order to evaluate the extent and the importance of the find is APPRAISAL OR DELINEATION DRILL. 226. Crude of high asphaltic content when subjected to distillation to remove the lighter fractions such as naphtha and kerosene leave asphalt as a residue. 227. Asphalt is dark brown or black in colour and at normal temperatures is a solid. 228. A unit of measure for crude oil and oil products equal to 42 U.S. gallons (159 litres) or BARREL. 229. Igneous or metamorphic rock lying below the sedimentary formations in the earth's crust is called as BASEMENT ROCK. 230. Out of control gas and/or oil pressure erupting from a well being drilled called as Blowout. 231. An assembly of heavy-duty valves attached to the top of the casing to control well pressure called as BOP. 232. A heavy, residual fuel oil used in ships' boilers and large heating and generating plants. BUNKER "C" FUEL OIL 233. Steel pipe used in oil wells to seal off fluids from the borehole and to prevent the walls of the hole from sloughing off or caving is called as Casing. 234. A reinforcing collar of steel screwed onto the bottom joint of casing to prevent abrasion or distortion of the casing as it forces its way past obstructions on the wall of the borehole. Casing shoes 235. Casing shoes are about 3 cm thick and 25 to 40 cm long and are about 3 cm larger in diameter in order to clear a path for the casing.

236. The three classes of clastic sedimentary rocks are sandstone, conglomerate and shale. 237. A well of sufficient production that it could be expected to pay for itself in a reasonable time and yield a profit for the operator. commercial well 238. Well completions vary according to the kind of well, depth and the formation from which it is to produce. 239. A well's surface pipe used to seal off near-surface water, prevent the caving or sloughing off the walls of the hole, and as a conductor of the drilling mud through loose, unconsolidated shallow layers of sand, clays, and shales. Conductor pipe 240. A line (as on a map) connecting points that have the same elevation above or below sea level is called as Contour line. 241. A map showing elevations by the use of contour lines.( contour map and Topographic map)

242. Lands for which petroleum or mineral rights belong to the government (CROWN LANDS)

243. Oil as it comes from the well; unrefined petroleum. (CRUDE OIL)

244. A wooden or steel structure built over a well site to provide support for drilling equipment. (DERRICK) 245. A four-stroke cycle internal combustion engine that operates by igniting a mixture of fuel and air by the heat of compression, and without the use of spark plugs. (DIESEL ENGINE) 246. An exploratory well that encounters a new and previously untapped petroleum deposit; a successful wildcat well. (DISCOVERY WELL) 247. Gas contained in solution with the crude oil in the reservoir. (DISSOLVED GAS)

248. A method of obtaining a sample of fluid from a formation using a "formation-tester tool" attached to the drillstem. (DST) 249. A volatile flammable liquid hydrocarbon mixture used as a fuel for internal combustion engines. (Gasoline) 250. The flexible, steel-reinforced, rubber hose connecting the mud pump with the swivel and kelly joint on a drilling rig. (MUD HOUSE) 251. Jack-Up mobile drilling rig is designed to operate in shallow water, generally less than 500 ft deep. 252. Piled Steel Platforms are conventional drilling and production platforms, and hundreds of them are installed offshore in many parts of the world. 253. Semi-Submersible rigs are floating drilling rigs consisting of hulls or caissons which carry a number of vertical stabilizing columns and support a deck fitted with a derrick and associated drilling equipment. 254. The rotary tool that is hung from the hook of the traveling block to suspend the drillstring and permit it to rotate freely. Swivel 255. Well log is a continuous record of measurement made in bore hole respond to variation in some physical properties of rocks through which the bore hole is drilled. 256. The spontaneous potential (SP) curve records the naturally occurring electrical potential (voltage) produced by the interaction of formation connate water, conductive drilling fluid, and shale. 257. The formation density log is a porosity log that measures electron density of a formation 258. Resistivity logs measure the ability of rocks to conduct electrical current. 259. SPE stands for (Society of Petroleum Engineers) 260. WPC stands for (World petroleum Congress) 261. AAPG stands for (American Association of Petroleum Geologists) 262. wire line logging are used for the identification of reservoir.

263. Wire line logging is used for the estimation of hydrocarbon in place. 264. Wire

line logging

is used for the estimation of


hydrocarbon. 265. Well logs are results of several geophysical measurements recorded in a well bore. 266. Well logging services are broadly classified into open hole logging, cased hole logging, production logging. 267. Type of Logging operations to be carried out at various rigs is decided based on the requirement of the well. 268. Porosity is about 25% (0.25) determined by examination of cores and/or a combination of density, neutron, or sonic logs. 269. The drainage area (the productive area), obtained from the geologist's maps, equals to about 250 acres. 270. The net pay thickness found from the gamma ray or SP logs. 271. The oil shrinkage factor is assumed, on the basis of experience and laboratory work with oils common to the area, to be 0.6. 272. The DST assembly consists of a valve, a packer, and a pressure recorder, with a section of perforated pipe at the bottom, through which formation fluids can flow. 273. The driller runs the drill string to the bottom of the hole with the valve closed. 274. The pressure recorder, located below the closed valve. 275. The pressure recorder, records the increasing weight of the column of mud above it (the hydrostatic pressure), on the outside of the drill string, as it goes down the hole. 276. Money payable to the lessor by the lessee for the privilege of deferring drilling operations or the commencement of production. DELAY RENTAL

277. The platform (usually 3 metres or more above the ground) of a derrick on which drilling operations are carried out; rig floor. DERRICK FLOOR 278. A member of the drilling crew who works up in the derrick racking tubing or drillpipe as it is pulled from the well and unscrewed by other crew members on the derrick floor. DERRICK MAN 279. The drilling and bringing into production of wells in addition to the discovery well on a lease. The drilling of development wells may be required by the express or implied covenants of a lease. DEVELOPMENT 280. Wells drilled for the purpose of producing petroleum from a proven field. Development wells are strategically located to get maximum production from the field. DEVELOPMENT WELLS

281. A fuel made of the light gas-oil range of refinery products. Diesel fuel and furnace oil are virtually the same product. Self- ignition is an important property of diesel fuel, as the diesel engine has no spark plugs; the fuel is ignited by the heat of compression within the engine's cylinders. DIESEL FUEL 282. The German engineer who invented the internal combustion diesel engine that bears his name. DIESEL, RUDOLPH 283. The technique of drilling at an angle from the vertical by deflecting the drill bit. Directional wells DIRECTIONAL DRILLING 284. Wells are drilled for a number of reasons: to develop an offshore lease from one drilling platform; to reach a pay zone beneath land where drilling

cannot be done; eg., beneath a railroad, cemetery, a lake; and to reach the production zone of a burning well to flood the formation. 285. A discovery well may also open a new producing formation in an established field. 286. The movement of oil and gas toward the well bore of a producing well. DRAINAGE 287. The maximum area in an oil pool or field that may be drained efficiently by one well so as to produce the maximum amount of recoverable oil or gas in such an area. A reservoir with good permeability will have a larger drainage area than one with less permeability. DRAINAGE AREA 288. The tool attached to the lower end of the drillpipe; a heavy steel "head" equipped with various types of cutting or grinding teeth, some are fixed, some turn on bearings. A hole in the bottom of the drill permits the flow of drilling mud being pumped down through the drillpipe to wash the cuttings to the surface and also cool and lubricate the bit. DRILL BIT 289. One who operates a drilling rig; the person in charge of drilling operations and who supervises the drilling crew. DRILLER 290. A person or company whose business is drilling wells. Some wells are drilled on a per foot basis; others are contracted on a day rate. DRILLING CONTRACTOR 291. A special mixture of clay, water and chemical additives pumped downhole through the drillpipe and drill bit. The mud cools the rapidly rotating bit; lubricates the drillpipe as it runs in the wellbore; carries rock cuttings to the surface; and serves as a plaster to prevent the wall of the borehole from crumbling or collapsing. Drilling mud also provides the

weight or hydrostatic head to prevent reservoir fluids (oil, gas or water) from entering the well bore and to counter the downhole pressures that can lead to a blowout. DRILLING MUD (MUD) 292. An offshore structure with legs anchored to the sea bottom. The platform, built on a large-diameter pipe frame, supports the drilling of a number of wells from the location. As many as 60 wells have been drilled from one large offshore platform. DRILLING PLATFORM (STEEL) 293. The most common type of drilling rig is the mechanical compound rig. Mechanical rigs use diesel engines coupled directly to the equipment or through compound shafts to drive the rotary, draw works, and mud pumps. Separate engine-AC generator sets provide lighting and power for auxiliary functions. DRILLING RIG (MECHANICAL) 294. Heavy, thick-walled steel pipe used in rotary drilling to turn the drill bit and to provide a conduit for the drilling mud. Joints of drill pipe are about 10 metres long are screwed together to form the drillstem. DRILLPIPE 295. A self-propelled vessel; a ship equipped with a derrick amid ships for drilling wells in deep water. DRILLSHIP 296. A drillship is self-contained, carrying all of the supplies and equipment needed to drill and complete a well. 297. The drillpipe. In rotary drilling, the bit is attached to the drillstem or drill column which rotates to "dig" the hole. DRILLSTEM (OR DRILLSTRING) 298. The tool consists of a packer to isolate the section to be tested and a chamber to collect a sample of fluid. If the formation pressure is sufficient, fluid flows into the tester and up the drillpipe to the surface. DRILLSTEM TEST (DST)

299. The DST is used to determine if any oil or gas is present, the reservoir pressure and the possible flow rate of the well. This information is critical in determining if the well will be a commercial discovery or a dry hole. 300. An unsuccessful well; a well drilled to a certain depth without finding petroleum in commercial quantities; a "duster". DRY HOLE 301. A method of keeping a drillship or semisubmersible drilling platform on target, over the hole during drilling operations where the water is too deep for the use of anchors. This is accomplished by the use of thrusters activated by underwater sensing devices that signal when the vessel has moved slightly off its drilling station. DYNAMIC POSITIONING 302. The search for oil and gas. Exploration activities include aerial surveying, geological studies, geophysical surveying, coring, and the drilling of wildcat wells. EXPLORATION ACTIVITIES 303. A seagoing, sophisticated research ship equipped with seismic, gravity, and magnetic systems for gathering data on undersea geologic structures. On the more advanced vessels of this type there are onboard processing and interpretation capabilities for the information gathered as the vessel cruises the oceans of the world. EXPLORATION VESSEL (SEISMIC VESSEL) 304. A fracture in the earth's crust accompanied by a shifting of one side of the fracture with respect to the other side. FAULT 305. The area encompassing a group of producing oil and gas wells; a petroleum pool. An oil field may include one or more petroleum pools, and have wells producing from several different formations at different depths. A roughly contiguous grouping of wells in an identified area. FIELD

306. Includes oil, natural gas and coal. Fossil fuels are formed in sedimentary beds from the remains of plants and animals that lived millions of years ago. FOSSIL FUEL 307. Land for which the petroleum or mineral rights are owned by a person rather than the government. FREEHOLD LAND 308. The owner of the land then has the right to lease such petroleum or mineral rights to a company who may wish to explore for petroleum or minerals. 309. A system of pipelines within an oilfield that collects oil from the different wells and brings it to a central location where it can be treated to remove impurities. GATHERING SYSTEM 310. Layers of sedimentary rocks which have been displaced from their normal horizontal position by the forces of nature. Folding, fracturing, and faulting are geological processes that often form structural traps that are logical places to look for accumulations of oil and gas. GEOLOGICAL STRUCTURE 311. A person trained in the study of the earth's crust. A petroleum geologist, in contrast to a hard-rock or mining geologist, is primarily concerned with sedimentary rocks where most of the world's oil has been found. In general, the work of a petroleum geologist consists of searching for structural traps favourable to the accumulation of oil and gas. In addition to deciding on locations to drill, he or she may supervise the drilling, particularly with regard to coring, logging, and running tests. GEOLOGIST 312. The science that deals with the history of the earth by studying the evidence preserved in rocks. GEOLOGY

313. Sensitive sound-detecting instruments used in conducting seismic surveys. A series of geophones are placed along the ground to detect and transmit, to an amplifier-recording system, the reflected sound waves created by explosions set off in the course of seismic exploration work. 314. A person who applies geophysical methods to the study of the earth. A specialist in geophysics. GEOPHYSICIST

315. The application of certain familiar physical principles - magnetic attraction, gravitational pull, speed of sound waves, the behaviour of electric currents - to the science of geology. GEOPHYSICS 316. A geophysical instrument used to measure the minute variations in the earth's gravitational pull at different locations. To the geophysicist, these variations indicate certain facts about subsurface formations. GRAVIMETER (GRAVITY METER)

317. An offshore drilling and production platform made of concrete and of such tremendous weight that it is held securely on the ocean bottom without the need for piling or anchors. GRAVITY BASE STRUCTURE 318. The results of a gravity survey contoured and displayed on a map. GRAVITY MAP 319. Organic chemical compounds of hydrogen and carbon atoms. There are a vast number of these compounds and they form the basis of all petroleum products. They may exist as gases, liquids, or solids. An example of each is methane, hexane, and asphalt. HYDROCARBONS

320. Sound-detecting instruments used in underwater seismic exploration activities. Hydrophones are attached to a cable towed by the seismic vessel. Sound waves generated by blasts from an airgun reflect from formations below the sea bottom and are picked up by the hydrophones and transmitted to the mother ship. HYDROPHONES A heat engine in which the combustion which generates the heat takes place inside the engine itself instead of in a furnace. Examples are the gasoline or diesel-powered engines used in automobiles. INTERNALCOMBUSTION ENGINE 321. A barge- like, floating platform with legs at each corner that can be lowered to the sea bottom to raise or "jack up" the platform above the water. Towed to a location offshore, the legs of the jackup rig are in a raised position, sticking up high above the platform. When on location, the legs are run down hydraulically or by individual electric motors. JACKUP RIG 322. A specially refined grade of kerosene used in jet propulsion engines. JET FUEL 323. A person whose primary duties are managing an oil company's relations with its landowners. Such duties include securing of oil and gas leases, lease amendments, and other agreements. LANDMAN 324. The legal instrument by which a leasehold is created. A contract that, for a stipulated sum, conveys to an operator the right to drill for oil or gas. The petroleum lease is not be confused with the usual lease of land or a building. The interests created by a petroleum lease are quite different from a realty lease. LEASE

325. A string of specially designed steel pipes that extends down from a drillship or floating platform to the subsea wellhead. Marine risers are used to provide a return fluid-flow conductor between the well bore and the drill vessel and to guide the drillstring to the wellhead on the ocean floor. MARINE RISER SYSTEM 326. Rocks formed by the metamorphosis of other rocks. When either igneous or sedimentary rocks are subjected to enough heat, pressure, and chemical action, their character and appearance are changed. METAMORPHIC ROCK 327. Mud is pumped through the mud hose to the swivel and down through the Kelly joint and drillpipe to the bottom of the well. MUD HOSE 328. Excavations near the rig into which drilling mud is circulated. Mud pumps withdraw the mud from one end of a pit as the circulated mud, bearing rock chips from the borehole, flows in at the other end. As the mud moves to the suction line, the cuttings drop out leaving the mud "clean" and ready for another trip to the bottom of the borehole. MUD PITS 329. A large, reciprocating pump that circulates drilling mud in rotary drilling. The duplex (twocylinder) or triplex (three-cylinder) pump draws mud from the suction mud pit and pumps the slurry downhole through the drillpipe and bit and back up the borehole to the mud settling pits. After the rock cuttings drop out in the settling pit, the clean mud gravitates into the suc tion pit where it is picked up by the pump's suction line. In rotary drilling there are at least two mud pumps, sometimes more. In case of a breakdown or other necessary stoppages, another pump can be immediately put on line. MUD PUMP 330. Portable metal tanks to hold drilling mud. Mud tanks are used where it is impractical to dig mud pits at the well site (as in the case of offshore drilling). MUD TANKS

331. Gaseous forms of petroleum consisting of mixtures of hydrocarbon gases and vapours, the more important of which are methane, ethane, propane and butane; gas produced from a gas well. NATURAL GAS 332. Crude petroleum and other hydrocarbons produced at the wellhead in liquid form. OIL 333. A mishap that permits oil to escape from a tank, an offshore well, an oil tanker, or a pipeline. Oil spill has come to mean oil on a body of water where even small amounts of oil spread and become highly visible. OIL SPILL 334. Any of various devices or contraptions to contain and prevent the further spread of oil spilled on water until it can be picked up. A curtainlike device deployed around or across the path of a drifting oil spill. The curtain is weighted on the bottom edge to hold it a foot to two below the surface and has floats on the upper edge to hold the curtain a foot or more above the surface. Once surrounded, the oil is sucked up by a vacuum cleaner-like suction pump. OIL-SPILL BOOM 335. An uncased well bore; the section of the well bore below the casing; a well in which there is no protective string of pipe. OPEN HOLE 336. Oil producing and exporting countries in the Middle East, Africa, and South America that have organized for the purpose of negotiating with oil companies on matters of oil production, prices and future concession rights. ORGANIZATION OF PETROLEUM EXPORTING COUNTRIES (OPEC) 337. A subsurface rock layer or formation that, owing to geological conditions, appears on the surface in certain locations. That part of a strata of rock that comes to the surface. OUTCROP 338. A measure of the resistance offered by rock to the movement of fluids through it. Permeability is one of the important properties of sedimentary rock containing petroleum deposits. The oil contained in the pores of the rock cannot flow into the well bore if the rock in the formation lacks sufficient permeability. PERMEABILITY

339. In its broadest sense, the term embraces the whole spectrum of hydrocarbons - gaseous, liquid, and solid. In the popular sense, petroleum means crude oil. PETROLEUM 340. The state or quality of being porous; the volume of the pore space expressed as a percent of the total volume of the rock mass; an important property of oil-bearing formations. Good porosity indicates an ability to hold large amounts of oil in the rock. And with good permeability, the quality of a rock that allows liquids to flow through it readily, a well penetrating the formation should be a good producer. POROSITY 341. A substance separated from a solution by chemical or physical change such as a change in temperature or salinity. Examples of precipitate rocks are salt, limestone and gypsum. PRECIPITATE 342. A program whereby fluids or gases are injected into a reservoir to maintain the pressure required to keep the petroleum flowing to the surface. PRESSURE MAINTENANCE PROGRAM 343. An offshore structure built for the purpose of providing a central receiving point for oil produced in an area of the offshore. The production platform supports receiving tanks, treaters, separators, and pumping units for moving the oil to shore through a submarine pipeline or by shuttle tanker. PRODUCTION PLATFORM 344. A general survey of an area to ascertain its main features, usually preliminary to a more detailed survey. RECONNAISSANCE SURVEY 345. A porous, permeable sedimentary rock formation containing quantities of oil and/or natural gas overlain by a layer of less permeable or impervious rock. RESERVOIR 346.

Sandstone, limestone, and other porous, permeable rock formations in which petroleum has accumulated. RESERVOIR ROCKS 347. Members of the drilling crew; the driller's assistants who work on the derrick floor, up in the derrick racking pipe, tend the drilling engines and mud pumps, and operate the pipe tongs when unscrewing the sections of drillpipe. ROUGHNECKS 348. An oil rig worker who works on a lease or around the drilling rig doing manual labour. ROUSTABOUT 349. A share of the minerals (oil and gas) produced from a property belonging to the owner of the property. Originally, the "royalty" was the percentage of the gold or silver taken from the realm that belonged to the king or queen. Today, the "sovereign" is the landowner who traditionally receives 12.5 percent or one-eighth of the oil and gas produced from his or her land. Although 12.5 percent has been the traditional royalty on oil and gas lease, this varies widely today. In very profitable areas, the royalty may be much higher. In marginally profitable areas, it may be much lower and in some cases there may be zero royalty. ROYALTY 350. Cuttings of a rock formation broken up by the drill bit and brought to the surface by the drilling mud. Rock samples are collected from the shale shaker and examined by the geologist to identify the formation and the type of rock being drilled. SAMPLE 351. A person hired by a company to seek out information about the exploration activities of other companies, including the location of geophysical surveys and the results of wells being drilled. SCOUT 352.

An extensive area (often covering thousands of square kilometres) where substantial amounts of sedimentary rocks are present. Most sedimentary basins are geologically depressed areas (shaped like a basin). The sediment is thickest in the middle and tends to thin out at the edges. SEDIMENTARY BASIN 353. Rock formed by the laying down of sediment by seas, streams, or lakes; sediment (mineral fragments, animal matter) deposited in bodies of water through geologic ages. Limestone, sandstone, shale and salt are examples of sedimentary rock. SEDIMENTARY ROCK 354. A plot or display of data acquired during a seismic survey with surface locations plotted ho rizontally and reflections from subsurface layers displayed vertically. SEISMIC SECTION 355. The investigation of underground rock layers by analyzing shock waves artificially produced at the surface and reflected from the subsurface layers of rock. SEISMIC SURVEY 356. A large floating drilling platform with a buoyant substructure; part of which is beneath the surface of the water. Semi-submersibles are virtually self-contained, carrying on their main and lower decks all supplies and personne l for drilling and completing wells in hundreds of metres of water at great distances from shore. Some of these huge platforms are selfpropelled and are capable of moving at 6 to 8 knots. As they often drill in waters too deep for conventional chain and cable anchors, they sometimes maintain their position over the borehole by the use of propellers or thrusters, controlled by onboard computers. SEMISUBMERSIBLE 357.

A pressure vessel (either horizontal or vertical) used for the purpose of separating well fluids into gaseous and liquid components. Separators segregate oil, gas, and water with the aid, at times, of chemical treatment and the application of heat. SEPARATOR 358. To cement casing in the hole. The cement is pumped downhole to the bottom of the well and forced up a certain distance into the annular space between casing and rock wall of the drillhole. It is then allowed to harden, thus sealing off upper formations that may contain water. The decision to set production casing is an indication that the operator believes the well is a commercial discovery. SET CASING 359. A small-diameter hole typically of 10 to 30 metres depth, usually drilled with a portable, truckmounted drill, for "planting" explosive charges in seismic operations. SHOT HOLE 360. Those sedimentary layers that contain the organic material that has been transformed into hydrocarbons by heat, pressure, and time. SOURCE ROCKS 361. A well drilled adjacent to a proven well but located in an unproven area; a well located a "step out" from proven territory in an effort to determine the boundaries of a producing formation. STEP-OUT WELL 362. A type of reservoir capable of holding oil or gas, formed by a change in the characteristics of the formation - loss of porosity and permeability, or a break in its continuity - which forms the trap or reservoir. STRATIGRAPHIC TRAP 363. A type of reservoir containing oil and/or gas formed by movements of the earth's crust which seal off the oil and gas accumulation in the reservoir

forming a trap. Anticlines, salt domes, and faulting of different kinds form structural traps. STRUCTURAL TRAP 364. The process whereby the earth's crust buckles downward under the weight of sedimentary layers being deposited in the area. SUBSIDENCE 365. A location where petroleum is seeping out of rocks at the surface. SURFACE SEEP 366. An area where a significant amount of petroleum has seeped out of the surface rocks and collected in a depression or pit. The lighter, more liquid fractions would have evaporated leaving a heavy tarry deposit. TAR PIT 367. A propeller used in manoeuvring a ship. THRUSTER 368. A supervisor of drilling operations in the field. A tool pusher may have one drilling well or several under his or her direct supervision. Drillers are directed in their work by the tool pusher. TOOL PUSHER 369. A map which shows in detail the physical features of an area of land, including rivers, lakes, streams, roads, and the elevation of those features. TOPOGRAPHIC MAP 370. A type of geological structure that retards the free migration of petroleum and concentrates the petroleum in a limited space. A mass of porous, permeable rock which is sealed on top and down both flanks by nonporous, impermeable rock thus forming a trap. TRAP 371. A hole drilled or bored into the earth, usually cased with metal pipe, for the purpose of discovering or producing gas or oil. Also, a hole for the

injection under pressure of water or gas into a subsurface rock formation for the purpose of maintaining the necessary reservoir pressure to keep the petroleum flowing to the surface. WELL 372. The work of preparing a newly drilled well for production. This is a costly procedure and includes setting and cementing the casing, perforating the casing, running production tubing, hanging the control valves, connecting the flow lines, and erecting storage tanks. WELL COMPLETION 373. A plan showing the best locations for the drilling of wells into a field with regard to getting maximum production for minimum cost. WELL SPACING GRID 374. A well drilled in an unproved area, far from a producing well; an exploratory well in the truest sense of the word; a well drilled out "where the wildcats prowl and the hoot owls mate with the chickens". WILDCAT WELL

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