A special class of saltwater muds in which sea water is used as the fluid phase.

Any of various materials, such as mica flakes or walnut hulls, that cure lost circulation.

See lost circulation, lost circulation material.

Usually a single well drilled offshore by a mobile offshore drilling unit to produce hydrocarbons from the outer fringes of a reservoir that cannot be produced by primary development wells drilled from a permanent drilling structure (as a platform rig).

Sometimes, several satellite wells will be drilled to exploit marginal reservoirs and avoid the enormous expense of erecting a platform.

A screen joint placed opposite perforations in sand control

A wireline used on drilling rigs and well servicing rigs to operate a swab or bailer, to retrieve cores or to run logging devices.

It is usually 9/16 of an inch (15 millimeters) in diameter and several thousand feet or meters long

Abbreviation: surface-controlled subsurface safety valve.

Any cementing operation after the primary cementing operation.

Secondary cementing includes a plug-back job, in which a plug of cement is positioned at a specific point in the well and allowed to set.

Wells are plugged to shut off bottom water or to reduce the depth of the well for other reasons.

A unit of viscosity as measured with a marsh funnel according to api procedure.

See api rp 13b, marsh funnel viscosity.

Any method by which large amounts of sand in a sandy formation are prevented from entering the wellbore.

Sand in the wellbore can cause plugging and premature wear of well equipment.

See gravel pack, sand consolidation, screen liner.

Determination of the relative percentages of substances, e.g., the suspended solids in a drilling fluid that pass through or are retained on a sequence of screens of decreasing mesh size.

Also called sieve analysis.

One of the pioneer companies in electric well logging, named for the french scientist who first developed the method.

Today, many companies provide logging services of all kinds.

An accessory to a fishing tool, placed above it.

If the tool cannot be disengaged from the fish, the safety joint permits easy disengagement of the string of pipe above the safety joint.

Thus, part of the safety joint and the tool attached to the fish remain in the hole and become part of the fish.

A compound that is formed (along with water) by the reaction of an add with a base.

A common salt (table salt) is sodium chloride derived by combining hydrochloric add with sodium hydroxide.

The result is sodium chloride and water.

Another salt is calcium sulfate, obtained when sulfuric acid is combined with calcium hydroxide.

A dome that is caused by an intrusion of rock salt into overlying sediments.

A piercement salt dome is one that has been pushed up so that it penetrates the overlying sediments, leaving them truncated.

The formations above the salt plug are usually arched so that they dip in all directions away from the center of the dome, thus frequently forming traps for petroleum accumulations.

See salt mud.