Chenier - An elongated, ridge-like, geologic formation, usually consisting of 

 sand and silt with minor amounts of shell material, located in 

 coastal areas. Cheniers exhibit a relief of about 1.5 m (5 ft), 

 similar to beach ridges, but differ in that they form a radiating, 

 chevron-like areal pattern. 



Christmas tree - The assembly of valves, pipes, and fittings, usually high 



pressure, used to control flow of oil and gas from the casing head. 



Circulating pit - A narrow channel dug into the earth or formed of steel that 

 allows drilling mud to flow from the shaker table to the mud pumps 

 where it is pumped down the drill tube to the drill bit. 



Climax community - The set of plants and animals associated with the climax 



stage of succession in ecosystem. The organisms of the climax stage 

 are a stable group that do not significantly change through time. 

 The community is characterized by a wide diversity of species, 

 complex food chains, and stable populations. 



Corrosion - The complex chemical or electrochemical process by which metal is 

 destroyed through reaction with its environment. 



Crude - Unrefined petroleum. 



Culm - The hollow stem of a grass; sometimes applied to sedges also. 



Cuspate - A type of delta formation in which a single dominant mouth builds 

 the delta forward into deeper water while wave action sweeps the 

 sediment away from the mouth to form two curving beaches, concave 

 toward the sea (tooth-shaped). 



Cuttings - Fragments of rock dislodged by the bit and brought to the surface 

 in the drilling mud. 



Dehydrator - A low-temperature separating apparatus used for removing water 

 vapor from a gas stream. 



Dendritic - A drainage pattern developed after the manner of a branched tree 

 or shrub; results from the absence of any systematic orientation of 

 controlling structures within the substrate. 



Detritus - Particles of plant matter in varying stages of decomposition. 



Development drilling - The drilling of wells in an oil/gas field with proven 

 development potential as opposed to exploration or "wildcat" drill- 

 ing. Wells are placed and production undertaken to maximize yield 

 for the field. 



Diatom - Any of a class of minute planktonic unicellular or colonial algae 



with silicified skeletons that form diatomite, which is particularly 

 useful as a light, friable filtering material. 



Disci imax community - a relatively stable ecological community often including 

 kinds of organisms foreign to the area and displacing the climax 

 because of disturbances, especially by man. 



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