Extremely high bottom hole temperatures can occur in deep wellbores or in areas of abnormally high [[geothermal gradient]]. These excessively high bottom hole temperatures (greater than [[temperature::250°C]]) can cause drilling problems because of the accelerated thickening of [[Drilling_fluid#Water-based_muds|water-based drilling fluids]]. The increase in viscosity and density of the drilling can may result in the following:
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Extremely high bottom hole temperatures can occur in deep wellbores or in areas of abnormally high [[geothermal gradient]]. These excessively high bottom hole temperatures (greater than [[temperature::250°C]]) can cause drilling problems because of the accelerated thickening of [[Drilling_fluid#Water-based_muds|water-based drilling fluids]]. The increase in [[viscosity]] and density of the drilling can may result in the following: