A system for transferring at least one subterranean core sample under pressure can include a retrieval vessel that collects and houses the at least one subterranean core sample at a sampling pressure at which the at least one subterranean core is collected. The system can also include a linear actuator that couples to the retrieval vessel through a valve in the open position at a first time, where the linear actuator facilitates removal of at least one pressure barrier from the retrieval vessel through the valve at the first time while maintaining the sampling pressure of the at least one subterranean sample. The system can further include a testing vessel that couples to the linear actuator through the valve in the open position at a second time, and a hydraulic device that facilitates pressurizing the testing vessel to the sampling pressure at the second time.

A method of transferring at least one subterranean core sample from a retrieval vessel to a testing vessel can include removing at least one pressure barrier on the retrieval vessel using a linear actuator while maintaining a sampling pressure on the at least one subterranean core sample at which the at least one subterranean core sample is taken from a subterranean formation. The method can also include pressurizing the testing vessel to the sampling pressure using the linear actuator, and transferring the at least one subterranean core sample from the retrieval vessel to the testing vessel. The method can further include sealing the testing vessel with the at least one subterranean core sample at the sampling pressure, where the testing vessel allows the at least one subterranean core sample to be tested while the at least one subterranean core sample is maintained at the sampling pressure.

A method of transferring at least one subterranean core sample from a retrieval vessel to a testing vessel can include removing at least one pressure barrier on the retrieval vessel using a linear actuator while maintaining a sampling pressure on the at least one subterranean core sample at which the at least one subterranean core sample is taken from a subterranean formation. The method can also include pressurizing the testing vessel to the sampling pressure using the linear actuator, and transferring the at least one subterranean core sample from the retrieval vessel to the testing vessel. The method can further include sealing the testing vessel with the at least one subterranean core sample at the sampling pressure, where the testing vessel allows the at least one subterranean core sample to be tested while the at least one subterranean core sample is maintained at the sampling pressure.

A method of coring to preserve subterranean soluble salt cements gives careful consideration to the selection and use of drilling fluids, specific logging of the zone of interest, displacing the near wellbore with an agent that when cured has either bound all subterranean water or cemented up all the available pore space, coring of the target formation zone containing the cured agent and retrieval of pressurized core material that allows CT scanning.

A method of coring to preserve subterranean soluble salt cements gives careful consideration to the selection and use of drilling fluids, specific logging of the zone of interest, displacing the near wellbore with an agent that when cured has either bound all subterranean water or cemented up all the available pore space, coring of the target formation zone containing the cured agent and retrieval of pressurized core material that allows CT scanning.

A method includes pumping an agent in a well across a target formation zone with rocks containing soluble salt cement. The agent is injected into pore space within the target formation zone extending a radial distance from the well using pressure, and the agent is allowed to cure in the pore space. The method further includes taking a core of the target formation zone containing the cured agent.

A method includes pumping an agent in a well across a target formation zone with rocks containing soluble salt cement. The agent is injected into pore space within the target formation zone extending a radial distance from the well using pressure, and the agent is allowed to cure in the pore space. The method further includes taking a core of the target formation zone containing the cured agent.

A core barrel sealing structure includes a core barrel, a drilling machine outer barrel, a chain mail-type flap valve and a trigger mechanism. The flap valve includes a valve seat and a chain mail-type valve flap. The trigger mechanism includes a trigger inner barrel and a trigger block. The trigger block is arranged in a through hole in a sidewall of the trigger inner barrel, and an inner wall of the drilling machine outer barrel is provided with a recessed opening adapted to the trigger block. When the core barrel is located in the valve seat, the valve flap is opened by 90° and is located between the trigger inner barrel and the drilling machine outer barrel. When the core barrel is lifted upwards, the valve flap returns to a top face of the valve seat to make sealing contact with a sealing face of a valve opening.

A core barrel sealing structure includes a core barrel, a drilling machine outer barrel, a chain mail-type flap valve and a trigger mechanism. The flap valve includes a valve seat and a chain mail-type valve flap. The trigger mechanism includes a trigger inner barrel and a trigger block. The trigger block is arranged in a through hole in a sidewall of the trigger inner barrel, and an inner wall of the drilling machine outer barrel is provided with a recessed opening adapted to the trigger block. When the core barrel is located in the valve seat, the valve flap is opened by 90° and is located between the trigger inner barrel and the drilling machine outer barrel. When the core barrel is lifted upwards, the valve flap returns to a top face of the valve seat to make sealing contact with a sealing face of a valve opening.

A drilling fluid channel structure of a core drilling rig includes a fluid channel activation module, a pressure relief module, a flow diverging and blocking module, a driving fluid channel and a cooling fluid channel. The fluid channel activation module, the pressure relief module and the flow diverging and blocking module are connected sequentially from the rear to the front. The driving fluid channel and the cooling fluid channel are connected at the rear side thereof to the flow diverging and blocking module. The driving fluid channel includes a driving section located between a stator and a rotor of a driving motor. The driving fluid channel is provided with a driving fluid outlet at the front side of the driving section. The cooling fluid channel passes through a layer disposed between an integrity-preserving compartment and an outer barrel.