A method transports and installs a heavy subsea structure such as a subsea processing center for produced crude oil or natural gas. The method includes controlledly flooding at least one ballast tank attached to or incorporated into the structure to the extent that the structure becomes negatively buoyant at a pre-determined towing depth. The method also includes towing the negatively-buoyant structure at the towing depth by the Controlled Depth Towing Method (CDTM). After towing to the installation location, the method includes further flooding the ballast tank to lower the structure onto the seabed. At the seabed, a fluid transportation pipe of a subsea production installation may be coupled to pipework of the structure.

A method includes mounting a lower platform block (300) to a plurality of piles (215) positioned on a surface. The lower platform block includes a first frame (315), a plurality of docking assemblies (305) connected to the first frame and engaging the piles, and a plurality of conductor tubes (310) connected to the first frame to a plurality of piles. The docking assemblies are released from the piles to separate the lower platform block from the piles.

A method includes mounting a lower platform block (300) to a plurality of piles (215) positioned on a surface. The lower platform block includes a first frame (315), a plurality of docking assemblies (305) connected to the first frame and engaging the piles, and a plurality of conductor tubes (310) connected to the first frame to a plurality of piles. The docking assemblies are released from the piles to separate the lower platform block from the piles.

Extender jumper systems and methods including an extender jumper system having an extender jumper assembly with a flowline and first and second connectors positioned at first and second ends of the flowline, and a support assembly configured to couple the extender jumper assembly to a support structure within a subsea field and to support the second connector to facilitate attachment between the second connector and a corresponding connector of another extender jumper or a jumper.

Extender jumper systems and methods including an extender jumper system having an extender jumper assembly with a flowline and first and second connectors positioned at first and second ends of the flowline, and a support assembly configured to couple the extender jumper assembly to a support structure within a subsea field and to support the second connector to facilitate attachment between the second connector and a corresponding connector of another extender jumper or a jumper.

A system is provided to perform various wellbore operations, including retrieval and replacement of solid internal tree caps, for example. The system may include an open water lubricator having a piston assembly disposed therein. The system may also include a well control package connected to a distal end of the open water lubricator. The piston assembly is configured to extend through the well control package. Method using systems disclosed herein may be performed while maintaining at least two testable pressure barriers during each of the retrieving and replacement steps.

In one illustrative embodiment, the manifold comprises a block with at least one drilled header hole formed within the block, a plurality of drilled flow inlet holes formed within the block, wherein the number of drilled flow inlet holes corresponds to the number of the plurality of external flow lines that supply fluid (e.g., oil/gas) to the manifold and a plurality of isolation valves coupled to the block wherein the valve element for each of the isolation valves is positioned within the block.

Computing systems, computer-readable media, and methods for seismic processing. The method includes receiving seismic data including acquired seismic waveforms that were acquired from a seismic receiver and represent a subterranean area, generating synthetic waveforms based on an initial model of the subterranean area, determining a model error by minimizing a local travel time shift error between one or more of the acquired seismic waveforms and one or more of the synthetic waveforms, and adjusting the initial model based on the model error to generate an adjusted model.

A modular subsea fluid storage unit comprises a variable-volume inner tank having a rigid top panel and a peripheral wall that is flexible by virtue of concertina formations. The peripheral wall is extensible and retractable vertically while the horizontal width of the tank remains substantially unchanged. A side wall of a lower housing part surrounds and is spaced horizontally from the peripheral wall of the inner tank to define a floodable gap between the peripheral wall and the side wall that surrounds the tank. An upper housing part extends over and is vertically spaced from the top panel of the inner tank and overlaps the side wall to enclose the inner tank. The floodable gap and the upper housing part enhance thermal insulation and trap any fluids that may leak from the inner tank.

The present invention relates to a hydrocarbon production inline manifold system. The inline manifold system includes a carrier pipe with a longitudinal carrier pipe axis. The carrier pipe is provided with a plurality of hubs each with a jumper port. A hub longitudinal axis is arranged perpendicular to the carrier pipe axis. The hub longitudinal axes of the plurality of hubs are in a common plane with the carrier pipe axis. A flow line is located inside the carrier pipe. At least one valve is located in a flowpath between each of the plurality of hubs and the flow line.