Abstract: A method for drilling a geothermal well in a subterranean zone includes drilling, with a drill string, a wellbore of the geothermal well in the subterranean zone. An inherent temperature of the rock adjacent a rock face at a downhole end of the wellbore is at least 250° C. While drilling, a drilling fluid is flowed at a temperature at the rock face such that a difference between the inherent temperature of the rock adjacent the rock face and the temperature of the drilling fluid at the rock face is at least 100° C.

Abstract: A system comprising an assembly of sensing elements that could be attached to, mounted upon, or installed into pipes for on-line, in-line or off-line characterization of fluid flows. The system may be hand-held by a human operator or implemented in benchtop instrumentation. The sensing elements comprise one or more sensors and one or more light-emitting diodes (LEDs) or lasers that can be configured in a variety of different orientations to investigate the fluorescence of the subject material by illuminating or exciting the subject material with the LEDs or lasers and collecting the electromagnetic signal returned from the subject material with the sensors. The architecture of the system is applicable to characterize both static and dynamic samples. Samples of the subject material include single-component solid, liquid, or gaseous materials or may also include single-phase, two-phase or multi-phase mixtures of solids, liquids and gases.

Abstract: Wellbore synthesis techniques are disclosed suitable for use in geothermal applications. Embodiments are provided where open hole drilled wellbores are sealed while drilling in sequenced operations with utilization of phase change materials to form an impervious layer at the wellbore/formation interface in high temperature applications. The techniques may be chemical, thermal, mechanical, biological and are fully intended to irreversibly damage the formation in terms of the permeability thereof. With the permeability negated, the wellbore may be used to create a closed loop surface to surface geothermal well operable in the absence of well casing for heat transfer surfaces for maximizing thermal transfer to a circulating working fluid. Formulations for the working and drilling fluids are disclosed.