In-tubing wellbore sidetracking operations

Abstract

Methods for wellbore operations in an earth wellbore with tubing within casing in an earth wellbore, the wellbore extending down into earth from an earth surface, the tubing including a tubing string with a lower end and extending down within the casing with the lower end at a point above a lower end of the casing, a tubing-casing annulus between the tubing and the casing sealed by a first sealing apparatus, the method including sealing the lower end of the tubing string with a sealing device to prevent fluid flow therethrough, and sealing the tubing casing annulus with a second sealing apparatus above and spaced apart from the first sealing apparatus. In certain aspects the sealing apparatuses provide upper and lower spaced-apart primary barriers. The methods in additional aspects include making an exit opening through the tubing and an exit opening through the casing, each exit opening located between the first sealing apparatus and the second sealing apparatus. In other aspects the methods include drilling a lateral wellbore from the exit opening through the casing. Apparatus is disclosed that is useful in such methods.