Lost circulation material

Drilling Fluids & Logging

Lost Circulation Material (LCM) refers to substances added to drilling fluid to seal fractures or cavernous formations and prevent the loss of whole mud into the formation. Loss of circulation is a major drilling hazard that can lead to a drop in hydrostatic head and a subsequent kick.

LCM comes in various forms: fibrous (cedar bark, mineral fiber), flaky (mica, cellophane), and granular (calcium carbonate, walnut shells). 'Pills' of high-concentration LCM are spotted across the loss zone to bridge the fractures and regain circulation.