Injection fluids formed of reverse emulsions and related methods of forming and using reverse emulsions for cavity control in solution mining. The reverse emulsion can reduce the volume of oil required to create an oil pad at the roof of a solution mining cavern in order to prevent vertical leaching and cavern collapse. The reverse emulsion can be formed from an emulsifier, a brine solution and oil. The emulsifier concentration can range from about 1% to about 5% by weight of the reverse emulsion. The emulsifier and the oil can be combined to form an oil/emulsifier mixture, wherein the oil/emulsifier mixture is combined with the brine solution to form the reverse emulsion. The oil/emulsifier mixture can be from about 1% to about 5% by weight of the reverse emulsion.

A method of drilling a subterranean geological formation is described. The method includes driving a drill bit to form a wellbore into the subterranean geological formation thereby producing a formation fluid including hydrogen sulfide (H.sub.2S). The method includes injecting a drilling fluid into the subterranean geological formation through the wellbore. The drilling fluid composition includes 0.25 to 2 wt. % of a primary H.sub.2S scavenger, which is potassium permanganate, and an invert emulsion, which includes a continuous phase including a vegetable oil which is at least one selected from the group consisting of corn oil, soybean oil, rapeseed oil, canola oil, sunflower oil, safflower oil, peanut oil, and cottonseed oil and a dispersive phase including water. The potassium permanganate present in the drilling fluid composition reacts with the H.sub.2S present in the formation fluid to produce a dispersion of manganese-containing particles which are at least one selected from the group consisting of manganese sulfide and manganese sulfate.

A method of drilling a subterranean geological formation is described. The method includes driving a drill bit to form a wellbore into the subterranean geological formation thereby producing a formation fluid including hydrogen sulfide (H.sub.2S). The method includes injecting a drilling fluid into the subterranean geological formation through the wellbore. The drilling fluid composition includes 0.25 to 2 wt. % of a primary H.sub.2S scavenger, which is potassium permanganate, and an invert emulsion, which includes a continuous phase including a vegetable oil which is at least one selected from the group consisting of corn oil, soybean oil, rapeseed oil, canola oil, sunflower oil, safflower oil, peanut oil, and cottonseed oil and a dispersive phase including water. The potassium permanganate present in the drilling fluid composition reacts with the H.sub.2S present in the formation fluid to produce a dispersion of manganese-containing particles which are at least one selected from the group consisting of manganese sulfide and manganese sulfate.

A method of drilling a subterranean geological formation is described. The method includes driving a drill bit to form a wellbore into the subterranean geological formation thereby producing a formation fluid including hydrogen sulfide (H.sub.2S). The method includes injecting a drilling fluid into the subterranean geological formation through the wellbore. The drilling fluid composition includes 0.25 to 2 wt.% of a primary H.sub.2S scavenger which is potassium permanganate. The drilling fluid composition includes an invert emulsion includes a continuous phase including palm oil and a dispersive phase including water. The potassium permanganate present in the drilling fluid composition reacts with the H.sub.2S present in the formation fluid to produce a dispersion of manganese-containing particles which are at least one selected from the group consisting of manganese sulfide and manganese sulfate.

A method of drilling a subterranean geological formation is described. The method includes driving a drill bit to form a wellbore in the subterranean geological formation thereby producing a formation fluid. The method includes injecting a drilling fluid into the subterranean geological formation through the wellbore. The drilling fluid includes 0.05 to 1 wt. % of a rhamnolipid surfactant based on a total weight of the drilling fluid. The drilling fluid includes an invert emulsion including a continuous phase and a dispersive phase including water.

A method of drilling a subterranean geological formation is described. The method includes driving a drill bit to form a wellbore in the subterranean geological formation thereby producing a formation fluid. The method includes injecting a drilling fluid into the subterranean geological formation through the wellbore. The drilling fluid includes 0.05 to 1 wt. % of a rhamnolipid surfactant based on a total weight of the drilling fluid. The drilling fluid includes an invert emulsion including a continuous phase and a dispersive phase including water.

A method of drilling a subterranean geological formation is described. The method includes driving a drill bit to form a wellbore into the subterranean geological formation thereby producing a formation fluid including hydrogen sulfide (H.sub.2S). The method includes injecting a drilling fluid into the subterranean geological formation through the wellbore. The drilling fluid composition includes 0.25 to 2 wt. % of a primary H.sub.2S scavenger which is potassium permanganate. The drilling fluid composition includes an invert emulsion which includes a continuous phase including mineral oil and a dispersive phase including water. The potassium permanganate present in the drilling fluid composition reacts with the H.sub.2S present in the formation fluid to produce a dispersion of manganese-containing particles which are at least one selected from the group consisting of manganese sulfide and manganese sulfate.

A method of drilling a subterranean geological formation is described. The method includes driving a drill bit to form a wellbore in the subterranean geological formation thereby producing a formation fluid. The method includes injecting a drilling fluid into the subterranean geological formation through the wellbore. The drilling fluid includes 1 to 3 wt. % of a weighting agent which includes hydrophobic metallic zinc nanoparticles including a metallic core and organic ligands present on a surface of the metallic core, based on a total weight of the drilling fluid. The drilling fluid includes an invert emulsion including a continuous phase and a dispersive phase including water.

A method of drilling a subterranean geological formation is described. The method includes driving a drill bit to form a wellbore in the subterranean geological formation thereby producing a formation fluid. The method includes injecting a drilling fluid into the subterranean geological formation through the wellbore. The drilling fluid includes 1 to 3 wt. % of a weighting agent which includes hydrophobic metallic zinc nanoparticles including a metallic core and organic ligands present on a surface of the metallic core, based on a total weight of the drilling fluid. The drilling fluid includes an invert emulsion including a continuous phase and a dispersive phase including water.

A method of assessing the effect of a production chemical on the stability of a water and oil emulsion, the emulsion comprising the production chemical, is provided. The method comprises: applying a potential difference across the emulsion at a detection site; measuring a current flowing through the emulsion due to the applied potential difference; and using this measured current to assess the effect of the production chemical. The step of using the measured current to assess the effect of the production chemical may comprise determining, based on the measured current, whether a critical potential of the emulsion has been reached or exceeded. The emulsion may be a crude oil emulsion. It may be a water-in-oil emulsion. The production chemical may be an emulsion breaker. Also provided is an apparatus for assessing the effect of a production chemical on a water and oil emulsion.