System and methods for treating subsurface formations containing fractures

Abstract

Methods of treating hydrocarbon containing formations are described herein. A method for treating a mudstone formation includes providing a substantially horizontal or inclined wellbore to mudstone formation; providing acid to the portion of mudstone formation such that a size of the fractures is increased; and allowing hydrocarbons to flow through the fractures.

Description

BACKGROUND[0001]1. Field of the Invention[0002]The present invention relates generally to methods and systems for production of hydrocarbons and / or other products from various subsurface formations such as hydrocarbon containing formations containing fractures.[0003]2. Description of Related Art[0004]Hydrocarbons obtained from subterranean formations are often used as energy resources, as feedstocks, and as consumer products. Concerns over depletion of available hydrocarbon resources and concerns over declining overall quality of produced hydrocarbons have led to development of processes for recovery that is more efficient, processing and / or use of available hydrocarbon resources. In situ processes may be used to remove hydrocarbon materials from subterranean formations that were previously inaccessible and / or too expensive to extract using available methods.[0005]Substantial reserves of hydrocarbons are known to exist in formations that have relatively low permeability. Examples of...

AI Technical Summary

Benefits of technology

The patent text describes methods for treating subsurface hydrocarbon formations containing fractures, such as mudstone and shale formations. The methods involve using acid to increase the width of microfractures in the formations and allow hydrocarbons to flow through them. The treatment can involve forming fractures by using acid or other fluids, and then adding proppant to improve the flow of oil and gas. The technical effects of the methods include increasing the size of microfractures and enhancing the flow of oil and gas from the formation.

Problems solved by technology

Recovery of hydrocarbons from low permeability subterranean formations is difficult because of the low mobility of fluids in the pore space in the subterranean formation (ultra-low permeability rocks).

This makes the production and injection of fluids from such reservoirs very difficult.

Similar problems are encountered in heavy oil reservoirs (reservoirs containing crude oil with a viscosity larger than about 100 centipoise).

Here too, the mobility of the fluids is small and it is difficult to inject and produce from the hydrocarbon bearing rock.

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