Patent ID: 6443227
Filing Date: 2002-09-03
Classification: C09K,E21B

Abstract:
A method for constructing subsurface structures oriented at a predetermined azimuth in a formation of unconsolidated and weakly cemented soil and sediments, comprising:drilling a bore hole with an axis in the formation of unconsolidated and weakly cemented soil and sediments to a predetermined depth; installing an injection casing with an outer surface in the bore hole at the predetermined depth, wherein an annular space exists between the outer surface of the casing and the bore hole; filling the annular space with a grout that bonds to the outer surface of the casing; weakening the injection casing along a vertical weakening line lying within a fracture plane, which fracture plane extends from the axis of the bore hole radially along the predetermined azimuth; injecting a fracture fluid into the injection casing with a sufficient fracturing pressure to dilate the injection casing, the grout, and the formation and thereby initiate a vertical fracture in the formation at the weakening line; controlling the fracture fluid based on a sequential incremental solution to determine incremental fracture geometry changes as the fracture is propagating; and forming a wall-like subsurface barrier layer with the propagating fracture fluid, wherein such barrier layer remains in place for the ongoing treatment or containment of a predetermined material permeating to the barrier layer through the formation of unconsolidated and weakly cemented soil and sediments.