reservoir thicknessreservoir valuationreservoir voidagereservoir volume factorresidual oilresidual oil and brine saturationresidual water saturationresistance logresistance loggingresistance to flowresistivimeterresistivity gradientresistivity indexresistivity methodrestrictor valveretuberetubingreversal of dipreverse circulationreverse circulation bitreverse circulation subreverse combustionreversed spreversing valverich gasrig helperrig shiftrig superintedentrig v downrigging timerigging up timeright hand drill piperight hand stringrigid loading armring groovering joint flangeriserriser angle indicatorriser buoyancyriser clampriser connectorriser mainriser stubriser tensionerriser tie inriveted casingriveted piperock bitrock boardrock destruction