#oil_well__oilwell  a well that yields or has yielded oil
  supertype:  well  a deep hole or shaft dug or drilled to obtain water or oil or gas or brine
  subtype:  gusher  an oil well with a strong natural flow so that pumping is not necessary
  subtype:  spouter.oil_well  an oil well that is spouting
  subtype:  wildcat_well__wildcatwell__wildcat  an exploratory oil well drilled in land not known to be an oil field

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