Petroleum Engineering Flashcards (Gas Liquification - Seismic)
Graben
a block of the formation that has slid downward between two faults.
Gneiss
a coarse, metamorphic rock with some parallel alignment of granular minerals and alternate bands of flaky or elongate minerals.
Grand Slam
a combination of logs or a computational procedure for calculating the depth of invasion and the resistivity of both invaded and uncontaminated zones, based on a dual-induction-laterolog and a proximity log or microlaterolog.
Gradiometer (seismic)
a device that measures an electric field at multiple points at the same time. The gradient is the difference in measured values per unit of distance between the measuring points.
Gradiomanometer (well logging)
a device that measures the density of fluids along a fluid column.
Gravimeter
a device that measures the local gravitational pull. Gravimeters are useful for determining small changes in the gravity. Very useful for detecting salt domes.
Gather (seismic)
a display of the input data in a stacking process designed to show all the seismic traces corresponding to the same depth.
Gauge Carrier
a downhole tool that houses gauges.
Gauge Hole
a drilled hole with no washouts; the same diameter as the bit.
Gel
a fluid with a higher than normal viscosity created by a gallant material such as polymer.
Gas Lock (facilities)
a gas retention device that permits gauging the tank without loosing gas to the atmosphere.
Glycol
a hydrate inhibitor or freeze-up preventer.
Gravel Pack Log
a neutron-type device that evaluates the packing completeness or condition of the gravel pack. The log is useful for estimating voids in the pack.
Gas Lock (pump)
a pump filled with gas that it cannot expel and where no further fluid will enter the pump. Common in beam lift pumps that pump off or are used in high GOR wells.
Gear Reducer
a pump or motor speed reducer.
Gauge (screens)
a rating where each gauge point equals 0.001§. A 12 gauge screen has 0.012§ openings (about 300 microns).
Geronimo Line (rig)
a safety slide or a line from the derrickman＊s platform to the ground, used in an emergency.
Gravel Pack
a sand control completion that uses a larger gravel to stop the formation sand and a screen to stop the gravel.
Granite wash
a sandstone with a large percent of weathered granite grains.
Gland
a seal around a moving rod.
Gauge Ring
a short, wireline-run tool that checks the id of a well bore.
Grain (formation)
a small piece of the formation composed of a single piece of sand.
Grapple
a spring like device, resembling a interlocking finger puzzle that allows a round work piece to slide through the ID when in compression, but grips the work piece (or fish) when a tension load is applied. Common in overshot fishing devices.
Graded Production Acreage (GPA)
a term that expresses the producability of a part of the reservoir for purposes of comparing one producing area to another.
Gate Valve
a valve with a sliding bar 每 common in the oilfield as tree valves.
Gravel
large, well sorted and consistently sized sand used to hold back a soft formation.
Grain (fluid loss additive)
literally grain or animal feed that is circulated with mud to act as a identifiable marker.
Gasoline
normally C7-C10 fuel, with a flash point of -40.
Glass Disk
often a rupture disk to allow a well to flow after it is broken by a dropped bar.
Geopressured
overpresured zone.
Gauge Pressure
pressure read by a gauge that is set to zero at atmospheric pressure.
Geiger-Mueller Counter
radioactive measuring device.
GLADTM
software package, gas lift assisted design.
Gauge (drilling)
the diameter of the bit of the hole drilled by the bit when there are no washouts.
Gathering Line
the flow line from the well to the separator or tank battery.
Gas Saturation
the fraction of the porosity in a zone that is occupied by free gas.
Geothermal Gradient
the gradient reflecting the amount of temperature rise as the well depth increases. Normally about 1.1 to 1.8o F per 100 ft of true vertical depth increase.
Geothermal energy
the heat of the earth, usually from produced natural steam, heat recovered from circulated water or direct heat-to-energy conversion (on-going research).
Gravity Drainage
the movements in a reservoir driven by gravity.
Gas-Oil Ratio
the number of standard cubic feet of gas contained in a barrel of oil.
Gas Liquification
the process of cooling gas to -162oC, reducing its volume by 600 fold over the gas volume at standard conditions.
Gasification
the production of gas from liquid or solid fuels.
Geophysics
the science of the physical properties of the earth.
Geology
the science that deals with the study of the planet earth.
Gel Strength (drilling)
the shear stress measured at low shear rate after the mud has set for a period of time.
Gravity (API)
the specific gravity of a fluid in API units, where fresh water is 10. Lighter gravity crude has higher API numbers.
Geothermal Wells
the wells that produce geothermal energy (heat).
Gravel Pack Evaluation Tool
uses porosity, density and/or tracer tools to determine presence of gravel and placement of gravel type between the screen and the hole or casing.
Geo-steering
using the formation data generated by a measurement while drilling system to assist in drilling a wellbore to a specific target in the formation.
Geophysicist
usually a professional involved with application of physics to geology, e.g., seismic interpreter.
Go Devil
various. A wireline cutter. A cleanout pig. A sleeve, etc.
Geologic Cross Section
vertical cross section (vertical is depth and horizontal is lateral distance) between two points through a rock section.
Gas Spiking
Adding gas to an injected fluid or treatment to reduce the injected water volume and provide energy for flowing the well back after the treatment.
GOS
gulf of Suez.
Gathering Agreement (contract)
an agreement detailing the conditions for entry of the producer's gas into the gathering system.
Gilsonite
an asphaltic drilling fluid loss additive.
Geophone
an instrument that detects vibrations passing through the earth＊s crust.
Gravimeter
an instrument that measures differences in the gravitational attraction. Particularly useful in finding salt domes.
Grainstone
an often high permeability limestone where large grains are in contact. Only high perm if fines are absent.
Gas Show
any indication of gas in the drilling fluid or cuttings that indicates gas production from a reservoir that has been drilled.
Gasket
any of several replaceable seals in equipment or tools.
Gas Permeation
invasion of gas into a solid, usually an elastomer, but sometimes referring to a metal.
Gradient
change in pressure or temperature per unit depth.
Granite
common igneous rock. No effective permeability.
Graviometer
device that records the specific gravity of a fluid.
Gravity Anomaly
difference between theoretical calculated and observed terrestrial gravity; excess gravity us positive and deficiency is negative.
Glycol Dehydrators
equipment for removal of water from natural gas.
GPM
gallons per minute.
GR
gamma ray log.
GLR
gas / liquid ratio.
GOC
gas / oil contact
GOR
gas / oil ratio. May refer to a solution GOR or total GOR.
GCI
gas cap injection.
GCV
gas control valve.
GIIP
gas initially in place.
GIV
gas injection valve.
GLM
gas lift mandrel.
GLV
gas lift valve.
GL (lift)
gas lift.
GNFT
gas no-flow test.
GPF
gas production facility.
GC
gathering center.
Glacial Drift
general term for debris and stones transported by glaciers.
GJ
gigajoule; 1,000,000,000 joules.
GIS
global information system.
GPS
global positioning system.
GPG
grains per gallon.
GPR
gravel pack replacement
GD
gravity drainage.
GHG
green house gasses.
GL (datum)
ground level.
GP/GL (subsea)
guide post guide line.
GLL (subsea)
guidelineless.
Gooseneck (coiled tubing)
the CT guide arch over the injection head.
Gauge Diameter
the OD of a bit or tool used downhole.
Gel Strength
the ability of a fluid to suspend solids.
Gravel Reserve
the amount of gravel above the top perf, after the job, in a well with deviation less than about 50o.
Geochemistry
the branch of chemistry dealing with the specialized reactions of downhole fluids and formations.
Gas-Oil Contact
the changing contact of the gas cap and the oil below in the rock.
Grain Density
the density of the rock components, without the effect of porosity.