Fracturing different levels within a completion interval of a well

A method for fracturing different levels of a completion interval of a subterranean formation which is traversed by a wellbore, said method comprising:

• positioning a workstring in said wellbore, said workstring including a cross-over and fracturing string;
• said fracturing string extending substantially through said completion interval and forming a completion interval annulus with said wellbore when said workstring is in an operable position within said wellbore;
• said fracturing string comprising:
• a string of blank, base pipe having a plurality of perforated sections spaced along its length;
• and
• at least one alternate flow path extending along said base pipe;
• forming blockage within said completion interval annulus at said perforated sections by flowing a fracturing slurry, comprised of a fracturing liquid and proppants, into said completion interval annulus whereupon some of said liquid from said fracturing slurry is lost into said completion interval and into said base pipe through said perforated sections, thereby effectively isolating those levels of said completion annulus which lie between respective adjacent, perforated sections;
• and
• fracturing at least some of said isolated levels of said completion interval by continuing to flow said fracturing slurry into said at least some isolated levels by delivering said fracturing fluid slurry said at least one alternate flow path to thereby fracture said different levels of said completion interval which lie adjacent said at lease some isolated levels of said completion interval annulus.