Changes

* Cavernous and open fissured

* Cavernous and open fissured

* Very coarse, permeable, and shallow, such as loose gravel

* Very coarse, permeable, and shallow, such as loose gravel

* Naturally or intrinsically fractured

* Naturally or intrinsically [[fracture]]d

* Easily fractured

* Easily fractured

* Underpressured or depleted

* [[Underpressure causes|Underpressured]] or depleted

Lost circulation results in increased mud expense and may cause subsurface blowouts. The proper drilling fluids and use of lost circulation material will minimize lost circulation.

Lost circulation results in increased mud expense and may cause subsurface [[Wikipedia:Blowout (well drilling)|blowouts]]. The proper drilling fluids and use of lost circulation material will minimize lost circulation.

==Bottom hole temperatures==

==Bottom hole temperatures==