Apparatus and method for formation evaluation

A probe assembly for employment by a downhole tool disposed in a wellbore surrounded by a layer of contaminated fluid, the wellbore penetrating a subsurface formation having a virgin fluid therein beyond the layer of contaminated fluid, the probe assembly comprising:

• a probe body extendable from the downhole tool;
• an outer packer carried by the probe body for sealingly engaging a first annular portion of the wellbore, the outer packer having a bore there through;
• a sampling tube disposed in the bore of the outer packer and forming an annulus there between, the sampling tube being extendable from the probe body under hydraulic pressure delivered from the downhole tool and carrying an inner packer on a distal end thereof for sealingly engaging a second annular portion of the wellbore within the first annular portion;
• a first inlet in the probe body fluidly communicating with the annulus for admitting one of virgin fluid, contaminated fluid and combinations thereof into the downhole tool;
• a second inlet in the probe body fluidly communicating with the sampling tube for admitting virgin fluid into the downhole tool;
• and
• a tubular brace disposed in the annulus for supporting the outer packer.

A packer for employment by a probe assembly carried on downhole tool conveyed in a wellbore penetrating a subsurface formation surrounded by a layer of contaminated fluid, the subsurface formation having a virgin fluid therein beyond the layer of contaminated fluid, the packer comprising:

• an elastomeric packer body having a distal surface adapted for sealingly engaging a portion of the wellbore, the packer body having an outer diameter and an inner diameter, the inner diameter being defined by a bore through the packer body, the packer body being further equipped with one or more channels formed in the distal surface and arranged in an annular cleanup intake intermediate the inner and outer diameters;
• a plurality of braces disposed in the one or more channels of the packer body and operatively connected to define a flexible bracing ring;
• and
• at least one passageway extending through the packer body for conducting one of virgin fluid, contaminated fluid and combinations thereof through the packer body.