Process and apparatus for completing a well in an unconsolidated formation

A process for installing a slotted liner and gravel pack within an unconsolidated hydrocarbonaceous fluid-bearing formation in a single trip into the formation, the formation having at least one hydrocarbonaceous fluid producing zone, the formation further having a bore hole drilled to a first pre-determined depth above the hydrocarbonaceous fluid producing zone and a well casing installed in the bore hole to about the first pre-determined depth, the well casing having an internal diameter, comprising the steps of:

• (a) lowering on a pipe string through the bore hole an apparatus for drilling and installing a gravel-packed liner, the apparatus including a drill bit for drilling a pilot hole, means for enlarging the pilot hole to a diameter larger than the pilot hole and sufficient for gravel packing, the pilot hole enlarging means being initially retracted and located above the pilot hole drill bit, a slotted liner having a first end and a second end, the first end joined to the apparatus above the pilot hole enlarging means and a drive assembly;
• (b) rotating the apparatus to drill a pilot hole through the hydrocarbonaceous fluid producing zone;
• (c) expanding the initially retracted pilot hole enlarging means upon exceeding the first pre-determined depth;
• (d) enlarging the pilot hole to a diameter larger than the pilot hole and sufficient for gravel packing;
• (e) continuing steps (b)-(d) until the first end of the slotted liner reaches a second pre-determined depth, the second pre-determined depth sufficient to place the slotted liner within the hydrocarbonaceous fluid producing zone;
• and
• (f) injecting a gravel slurry into an annulus defined by the enlarged hole and slotted liner to gravel pack the annulus.