Abstract: A method of completing a subsea borehole including connecting a first vessel to a subsea wellhead assembly via a riser. A borehole is drilled with a drill string communicated to the subsea wellhead assembly through the riser. A lower completion assembly is run on a service string into the borehole through the riser. At least two barrier valves of the lower completion assembly are set with the service string in order to form a mechanical barrier to fluid flow with each of the at least two barrier valves. The riser is disconnected from the subsea wellhead assembly. An upper completion string is run through open water to the borehole and connected to the lower completion assembly. An lower completion assembly for a subsea borehole is also included.

Abstract: A method of completing a subsea borehole including connecting a first vessel to a subsea wellhead assembly via a riser. A borehole is drilled with a drill string communicated to the subsea wellhead assembly through the riser. A lower completion assembly is run on a service string into the borehole through the riser. At least two barrier valves of the lower completion assembly are set with the service string in order to form a mechanical barrier to fluid flow with each of the at least two barrier valves. The riser is disconnected from the subsea wellhead assembly. An upper completion string is run through open water to the borehole and connected to the lower completion assembly. An lower completion assembly for a subsea borehole is also included.

Abstract: A gravel packing system includes at least two packers with at least one of the two packers being sealable to an open hole, a barrier sealably engaged with the at least two packers defining an annular space between the open hole and the barrier, a cross-over tool operably connectable to at least one of the at least two packers and the barrier, and at least one regulator in operable communication with the barrier configured to maintain a substantially constant pressure in the annular space while gravel is packed at a location downstream of at least one of the at least two packers, downstream being defined by a direction of travel of gravel being packed.