The Dendritic Well: A Simple Process Creates an Ideal Reservoir Drainage System

Abstract Oil and gas wells are constructed with the intention of accessing and recovering hydrocarbons from permeable rock formations. Ideally, we would like to do that as quickly and as efficiently as possible. Unfortunately, we generally try to accomplish this goal by drilling only a few wells and depending on the native rock permeability, or the presence of natural fractures, to convey hydrocarbons to these few wells. This process is inefficient and, ultimately, leaves significant reserves unrecovered. Natural processes often offer valuable insight into the most effective ways to exploit, or distribute, resources. If reservoir engineers could drill wells, they would surely not drill a single, small diameter hole, with the walls of that hole damaged to the point they are initially impermeable. They would more likely construct a network of branches, mimicking the root structure of plants, evolved to efficiently drain nutrients from a soil reservoir. This type of network, for the collection or distribution of materials, is a frequently repeated feature in natural systems and clearly represents a highly efficient method to access resources, of one kind or another. Such a network could maximise the contact between reservoir and wellbore and distribute inflow across an enormous surface area. This is the "Dendritic Well" – until now, an impractical concept but one that may have some future with further refinement of the technique reported here. This paper describes several wells where multiple, relatively short-length laterals were constructed by pumping hydrochloric acid though a specially designed jetting assembly, attached to the bottom of a 1/" coiled tubing unit. This revolutionary method creates a "reservoir engineer's" hole, using simple equipment at low-cost. A highly stimulated lateral tunnel, branching from the original well with a fractal of smaller branches (wormholes) born out of the lateral hole, mimicking a plant root, is the end product.