Abstract: A method of packing a well, particularly an oil, gas or water well comprises injecting a particle/liquid slurry into a wellbore wherein the particles comprise particles of at least two different densities independently selected from the density range of about 0.1 to about 4.0. The at least two different density particles may be injected as blend of different density particles or in a sequential series of slugs, each slug having a single density particle suspended therein. This technique gives substantially equivalent packing efficiency throughout the annulus, perforations and perforation chambers when compared with gravel packing using specialized low to medium density materials.

Abstract: A pyrolytic carbon coated particle for use in well fracturing and sand control applications comprising: a thermally stable substantially spherical substrate particle (e.g., ceramic composite bead or the like) and a substantially uniform layer of pyrolytically deposited carbon encapsulating said thermally stable substantially spherical substrate particle. Such carbon coated particles exhibit physical properties superior to materials commonly used in gravel pack and well fracturing operations as well as improved chemical resistance to acids, organics and steam.