Adjustable coring assembly and method of using same

A coring assembly for obtaining a core sample of a subterranean formation, the coring assembly deployable into a wellbore penetrating the subterranean formation, the coring assembly comprising:

• a coring tool carried by a downhole tool and having a coring cavity to receive the to the core sample;
• a coring extender carried by the downhole tool, comprising:
• a housing operatively connectable to the downhole tool, the housing having a plurality of fluid chambers therein;
• a mandrel positionable in the housing, the mandrel comprising a locking tube operatively connectable to the housing and a coupling tube operatively connectable to the coring tool, the locking tube operatively connectable to the coupling tube and adjustably positionable relative thereto such that a length of the mandrel is adjustably defined therebetween, the coupling tube having an outer surface slidably positionable along an inner surface of the housing;
• and
• seals positionable between the mandrel and the housing to define a fluid pocket to isolate the fluid therebetween as the coupling tube moves along the housing whereby the fluid permitted to flow about the fluid pocket to balance between the fluid chambers.

A method of obtaining a core sample of a subterranean formation, the method comprising:

• deploying a coring assembly into the wellbore via a downhole tool, the coring assembly comprising a coring tool having a coring cavity to receive the core sample and a coring extender operatively connectable to the coring tool, the coring extender comprising a housing and a mandrel, the mandrel comprising a locking tube and a coupling tube, the housing having a plurality of fluid chambers therein;
• adjusting a length of the mandrel in the housing by slidably positioning the coupling tube along the locking tube;
• sealing a fluid in a pocket between the coupling tube and the housing;
• permitting the fluid to flow in the pocket and to balance between the plurality of fluid chambers as the coupling tube moves along the housing;
• and
• receiving a coring sample into the core cavity.