Controlled Horizontal Drilling

Abstract

Abstract Very recently a conventional drilling assembly, directional Measurement While used to drill (MWD) and steerable system were used to drill in the first successful horizontal well in Michigan's shallow Antrim gas zone. This essay is an analysis and evaluation of the technology applied and the procedure used to achieve a successful horizontal status. An explanation of the controlled drilling methods used to maintain a lateral status in the "Hot Zone" (anticipated high gas producing zone) is provided as well as case producing zone) is provided as well as case history information from the actual field operations. An analysis of the economics of such a project is examined, along with a project is examined, along with a comparison of this well design versus straight hole drilling. The key issue in this project is the evaluation of the gas production, which is the prime economic production, which is the prime economic factor that will determine the future of similar projects. The hypotheses offered by various operators were researched, and comparisons made to proven theories provide actual case history data for future lateral wells. As more well information becomes available from current projects, it is anticipated that operators will plan new projects to maximize their production using projects to maximize their production using their research and case history data to minimize their expenses. The results of this lateral project are objectively presented so that specific conclusions may be drawn. Similar projects are highlighted to ensure that a fair and accurate evaluation can be derived from this project. Introduction Controlled Horizontal Drilling was successfully accomplished with the use of a conventional drilling assembly (see Fig. 1) in Michigan's Antrim Shale. This well is located in Section 20 of Bagley Township. Otsego Co., Michigan (see Figs. 2–3). The Antrim formation is a black shale of the late Devonian Age and overlies the Traverse formation (see Fig. 4). this hydrocarbon zone was expected to be topped at a true vertical depth (TVD) of 1450 ft (442 m) + 10 ft (3 m) with the best production theorized to be drawn from the "Hot Zone" of the bottom 20 ft (6 m) of the shale (see Fig. 5). Current Antrim gas projects are geologically based on structural relief fractures, vertical in nature, that are conducive to providing gas flow channels (see Fig. 6). Case history wells have proven that utilizing a nitrogen foam fracture treatment carrying a sand propellant has enhanced the gas production. A typical Antril well has an production. A typical Antril well has an average daily production of 70–80 MCF of dry gas with 40–80 barrels of salt water. The general theory that more production was applied to this project, along with the belief that drilling horizontally through the vertical fractures would also add to increased gas production. Previous attempts to drill medium or long radius horizontal wells had failed; therefore this well was designed to utilize the maximum available well bore, with the least amount of anticipated build rate/100 ft (30 m). All depths reported, unless otherwise specified, will be in measured depth (MD) with corresponding true vertical depths recorded in Table 1. P. 749