Abstract: The present invention provides methods for forming multiple wellbores from a single location. A relatively large diameter main wellbore is drilled to a known depth. A plurality of spaced apart wellbores are formed from the bottom of the main wellbore, wherein at least one such wellbore is a production wellbore for producing hydrocarbons from subsurface formations. Wellhead equipment for each production wellbore is installed at main wellbore bottom. Additional devices or equipment are also placed in the main wellbore, preferably near the bottom.

Abstract: The present invention provides a system for drilling boreholes having a downhole subassembly which contains an acoustic measurement-while-drilling system. The acoustic system contains an acoustic transmitter and receiver for determining the acoustic velocity through the formations surrounding the borehole ad an acoustic transmitter and a set of receivers for determining the bed boundaries surrounding the borehole formation utilizing the acoustic velocities measured by the system. The downhole subassembly also contains a computing system which performs computations downhole and transmits certain answers uphole during the drilling operations. The bed boundary information is utilized to drill the wellbore along a desired wellbore path. The downhole computing system correlates the acoustic sensor measurements with other measurement-while-drilling measurements and transmits selected correlated information uphole.

Abstract: A device for measuring the cross section of the stator of a downhole motor having a carrier shaped to travel through the helicoidal interior of the stator and a sensor including first and second bending beam-strain gage structures for generating electrical signals indicative of the cross section of the stator.

Abstract: Real time responsive devices are mounted at the inlet to an in-hole motor to measure the interval of time during which drilling fluid circulates through the motor.