Synthetic Sweet Spots in Tight Formations by Injection of Nano Encapsulated Reactants

Abstract

Provided is a method and composition for the in-situ generation of synthetic sweet spots in tight-gas formations. The composition can include gas generating compounds, which upon activation, exothermically react to generate heat and gas. The method of using the composition includes injecting the composition into a tight-gas formation such that upon activation, the heat and gas are generated, resulting in the formation of fractures and microfractures within the formation.

Description

RELATED APPLICATIONS[0001]This application claims priority to U.S. provisional patent application Ser. No. 61 / 563,323, filed Nov. 23, 2011, the disclosure of which is incorporated herein by reference in its entirety.FIELD OF THE INVENTION[0002]This invention relates to methods for preparing synthetic sweet spots in tight hydrocarbon containing formations.BACKGROUND OF THE INVENTION[0003]The search for and recovery of oil is becoming increasingly difficult as world-wide petroleum reserves decline. In many instances, reserves trapped within certain low permeability formations, such as certain sand, carbonate, and / or shale formations, exhibit little or no production, and are thus economically undesirable to develop at current oil and gas prices. In certain unconventional formations, such as low permeability formations, the most important element that determines whether developing reservoir will be economically viable is finding sweet spots in the reservoir. It is well established that ...

AI Technical Summary

Benefits of technology

The patent describes a method for improving the production of gas from tight-gas formations. The method involves injecting an aqueous solution containing an encapsulated reactant that can produce gas when it reacts exothermically. The reactant is coated to allow for delayed erosion, which creates fractures and microfractures within the formation, resulting in better gas production.

Problems solved by technology

The search for and recovery of oil is becoming increasingly difficult as world-wide petroleum reserves decline.

In many instances, reserves trapped within certain low permeability formations, such as certain sand, carbonate, and / or shale formations, exhibit little or no production, and are thus economically undesirable to develop at current oil and gas prices.

Unfortunately, current technologies are unable to locate or predict when and where sweet spots exist within a given formation.

Tight sands and shale are gas bearing but very low permeability formations, and thus present difficulties in recovering hydrocarbons therein.

The fracturing treatment is often logistically very challenging and therefore can be commercially very cumbersome.

The chances of encountering the sweet spot, however, are low.

The current exploration technologies are, to a certain extent, helpless in detecting them.

In tight reservoirs, due to low permeability of the formation, well productivity is typically low, thus making the well non-economical from a standpoint of development.

These methods, however, have limited uses.

Multistage fracturing has raised many concerns due both to the high cost and because of the very large amounts of water that are required.

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