Humification - Formation of, or conversion into, humus. 



Hydric forest - A forest type characterized by an abundance of moisture, such 

 as a bottomland hardwood forest. 



Hydrologic gradient - The difference in level of the water table between two 

 points causing water to flow very slowly toward the lowest point 

 within the groundwater body. 



Hydroperiod - That time duration that water is present in the upper soil 

 layers. 



Injector well - A well used for the disposal of brine or produced water to 



subsurface formations. Water injection also increases oil recovery 

 by forcing residual oil out of producing formations. 



Isolation - The rate of delivery of direct solar energy per unit of horizontal 

 surface. 



Jetting barge - A barge having hydraulic pumps that can excavate a pipeline 

 trench in bottom sediments by use of a high-pressure water jet. 



Kelly - The heavy square. or hexagonal steel member which is suspended from a 

 swivel through the rotary table and connected to the drill pipe to 

 turn the drill string. The kelly transmits torque from the rotary 

 to the drill string, yet it allows limited vertical movement as the 

 bit deepens the hole. 



Keyway - A specially constructed slot at one end of a drilling barge through 

 which the drilling takes place. This arrangement permits the 

 drilling rig to be entirely contained on the barge. 



Launcher - An entry port to a pipeline through which large balls, pigs, or 



scrapers can be put into the pipeline bore to separate liquids or to 

 clean the inside of the pipe. 



Lay barge - A special assembly barge used in the flotation method of pipeline 

 installation to assemble, process, and install gas and oil pipe in 

 aquatic areas. 



Log - A systematic recording of data, as in driller's log, electrical log, 

 radioactivity log. 



Magnetometer survey - A survey (often by airplane) to detect differences in 

 magnetic fields, which can indicate the presence of geologic forma- 

 tions characteristically associated with gas and oil deposits. 



Mastic - Pipeline coating materials composed usually of coal tar or asphalt 

 base materials. The primary purpose of this coating is to prevent 

 water from coming into contact with the steel of the pipe and causing 

 corrosion. 



Meiofauna - A practical term relating to small benthic organisms. This group 

 includes such things as nematodes, ostracods, small polychaetes and 

 oligochaetes, amphipods, and harpacticoid copepods, but does not 

 normally include the protozoa. 



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