Exxon Production Research Company

Walter J Lamb

Manuel Eduardo Gonzalez

Dale E Nierode

James R Bailey

Kenneth R Kunze

Richard M McKinley

A method for stimulating production from wells drilled into natural gas reservoirs characterized by lenticular deposits. The reservoir thickness through which the wells are drilled is divided into multi-stage zones that are further divided into single-stage zones. Each single-stage zone is perforated and then fractured. The fracturing is conducted in multiple stages to sequentially fracture each of the single-stage zones within a multi-stage zone; the fracturing stages being separated by ball sealers. Well spacing may also be controlled to match fracture drainage and size of the lenticular deposits.

Method for stimulation of lenticular natural gas formations

A neutron logging tool is used to obtain information about fluids within a wellbore. The well is shut in and a neutron log count rate (M.sub.gas) is obtained in a portion of the wellbore containing primarily gaseous fluid and a neutron log count rate (M.sub.liquid) is obtained in a portion of the wellbore containing primarily liquid fluid. Then fluid flow is reestablished in the well and a neutron log count rate (M.sub.mix) is obtained over a logging interval of interest. Previously obtained calibration data relates (M.sub.gas), (M.sub.liquid), and (M.sub.mix) to relative quantities of gaseous fluid and liquid fluid within the wellbore.

Neutron logging method for quantitative wellbore fluid analysis

Ball sealers comprising a polyetheretherketone are introduced into a well to seal well perforations and divert fluid therein. In the preferred embodiment the ball sealers have a density less than the treating fluid.

Well treatment using ball sealers

A method for improving the permeability in a subterranean formation by acid treatment is disclosed. In this method, an aqueous acidizing solution containing hydrofluoric acid and excess fluoride is injected into the formation. The acidizing solution dissolves siliceous materials and reduces precipitation of dissolved species from the spent acidizing solution. Further, the acidizing solution has lower acidity than presently employed acidizing solutions and thus a reduced tendency to corrode wellbore tubing and equipment.

Growing community of inventors

Houston, TX, United States of America

Walter J Lamb