What is geothermal drilling: A process that cuts or enlarges holes of circular cross section for hard materials is known as drilling. The process of creating holes in the earth to extract the earth's heat is known as Geothermal Drilling. Generally a drill bit is used in drilling as a rotary cutting tool. At hundreds to thousands of revolutions per minute the drill bit is rotated and pressed against the workpiece. This allows the cutting edge to remove chips from the hole. In drilling the resource is stored in the form of volcanic or hard sedimentary rocks. We may often come up with the names Drill Bit and Drilling Rig. Let's have a brief discussion about it. Drill Bit: These are used as cutting tools that create circular holes. These come in many sizes and include many uses. These are fixed in a tool called a drill which rotates them and provides the force to create holes. There are some drill bits available that are used for non-cylindrical shaped holes. The important part of the tip is the shank. It is present at the other end of the drill bit. There are many types and types of drill bits. Each tip has its own specifications. Drilling Rig: A massive structure or machine that creates holes and is also used to drill water wells, oil wells, or natural gas extraction wells. These pits can also be small and can be moved manually by one person. Rig Selection: Rig selection will be based on well parameters such as diameter, depth and casing design. With the parameter criteria we will determine what type of rig should be used. Factors that determine hole diameter: • Recording tools: Recording tools will accommodate virtually any reasonable hole size, but if more complex tools, particularly imaging tools such as a training micro-scanner, define the size minimum of the hole.• ...... half of the paper ...... in the difficulty of landing the casings Enlargement of the hole: Here the size of the hole is very large than expected and necessary and the problems related to these are Erosion hydraulic Mechanical abrasion caused by drill string Shale intrinsically breaking off Fracture Occurs when the pressure of the well drilling fluid crosses the formation-fracture pressure. Associated problems are loss of circulation and the occurrence of kicks. Collapse Well collapse occurs when the drilling fluid pressure is much lower to maintain the structural integrity of the hole. Associated problems are clogging of pipes. Ref: http://petrowiki.spe.org/Borehole_instability#Types_and_associated_problemsLost Circluation: is the partial or total loss of drilling fluid. When the hydrostatic pressure is greater than the breaking strength, cracks are created and the fluid leaks and flows.