The Oak Canyon Fire southeast of Dufur is now 90 percent contained.  It has burned 930 acres since it ignited Friday evening, and is burning in light grasses, brush and some juniper on private lands.   Fire line has nearly been completed around the fire area and crews will continue to work into the evening and tomorrow securing those lines.  Two 20-person crews are working the fire in addition to five rappellers, six engines, four helicopters and two Single Engine Air Tankers.  Aerial resources supported the crews on the ground in addition to helping to keep the fire out of the Deschutes River basin.   The fire is human caused, but an exact cause has not yet been released.