Patent ID: 6991048

Claim:
A method for drilling wellbores, comprising: drilling a main wellbore; disposing a casing string having a deflecting member at a lower end thereof in the main wellbore; disposing a drill string having a drill bit at a lower end thereof in the casing string; drilling, with the drill bit, a first lateral wellbore at a first depth in the main wellbore; transferring the casing string to a second depth in the main wellbore that is less than the first depth; disposing a first temporary plug in the main wellbore at the second depth to prevent gas from flowing up the main wellbore past the second depth without removing the casing string from the main well bore; transferring the casing string to a third depth in the main wellbore that is less than the second depth; drilling, with the drill bit, a second lateral wellbore at the third depth; and removing the first temporary plug, wherein removing the first temporary plug comprises either drilling through the first temporary plug or dissolving the first temporary plug.