Proppants are used to keep hydraulic fractures open,allowing for reservoir fluids to flow back after external pressure is withdrawn.Proppants are carried by the hydraulic fracturing fluid containing multiple components such as polymers,breakers,or friction reducing agent.These proppant systems have certain disadvantages such as formation and fracture permeability damage due to the viscous gel residue,risk of early screen-out and reduced effective propped area due to proppant excessive leakoff or settling,and abrasion to the pumping equipment and tubular. Acid fracturing is another fracturing technique.It is used in carbonate reservoirs,in which the acid etches the fracture faces to create conductive path.The drawbacks of acid fracturing include short acid etch length due to rapid acid-carbonate rock reaction rate and corrosion to the tubular. The oil and gas industry has been relying on these hydraulic fracturing techniques to proliferate production from low permeability reservoirs,and has made significantly advancement in tools and chemicals used in the fracturing processes.However,the maximized production and recovery is still unattainable due to the reasons mentioned above.This paper discusses a novel chemical compositions and process to overcome the challenges encountered by the current fracturing techniques.The goal is to convert injected fracturing fluid into a highly permeable proppant pack in-situ.Since the fracturing fluid itself forms the proppant,it can penetrate the entire fracture length,height,and complex network, maximizing the effective fracture area and stimulated reservoir volume.The rendered particle size can be significantly larger than conventional proppants without the concern of screen-out.The in-situ formed proppants have strength sufficient to resist fracture closure stress.In addition,no polymer is required to suspend the proppant;therefore no gel residue will be left to damage fracture conductivity. Though it is in its preliminary development stage,interesting and encouraging test results have been obtained.Formulations,photos,and mechanical properties of in-situ generated proppants will be pre- sented in this paper.
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