Horizontal Open Hole, Dual-Lateral Stimulation, Using a Multilateral Entry with High Jetting Tool

Abstract

The number of multilateral gas producers drilled in the Ghawar field has significantly increased over the past few years as part of the reservoir development strategy to maximize well productivity through maximum reservoir contact. Although these wells are expected to require little rigless intervention to conduct surveillance or productivity enhancement work, the effective options available to selectively access each of the laterals are limited. Thus specialized tools and techniques are required but the complex nature of these deep wells, combined with the high pressure and temperature characteristics of the reservoir, makes their application difficult and the outcome of the well intervention procedures uncertain. One of the techniques that has proven successful in different fields around the world, is the use of a lateral accessing tool to selectively access the desired lateral to then perform a stimulation treatment, run a production log, or any other operation. Combining lateral accessing and high-pressure jetting tools to access and stimulate two under-performing laterals a world first, was done in Well A, a producer drilled in a carbonate reservoir in Saudi Arabia's Ghawar field. The stimulation treatment was successful and the well achieved a two-fold rate increase. This paper provides details about the pre-job research and testing conducted, the methodology, equipment and procedure successfully applied in dual-lateral Well A, and lessons learned throughout the operation. The post-treatment performance of the well was better than anticipated, which encouraged Saudi Aramco to further utilize the technique for different applications. Introduction Although lateral accessing tools have been successfully used in wells around the world over the past few years, the gas producer selected for the first trial of this technique posed considerable challenges because of its casing size and the long length and heavy weight of the bottom-hole assembly, comprising the accessing and high jetting tools, that was run on coiled to access the lateral sections. Multilateral candidates provide options to increase the productivity of gas fields during their productive lives, using an effective stimulation treatment. This was the first successful attempt to access each lateral in a multilateral well. Previous unsuccessful attempts resulted in having to bullhead stimulation treatments in wells with a similar configuration, with relatively poor results.

Successful Implementation of Abrasive Perforation in Highly Deviated HP/HT Gas Well

“…A 2 1/8 inch FOBHA including CCL, BHP, and BHT tools was used with a high pressure jetting tool (3) . The execution sequence of this run was as follow:…”

“… Fiber optic enabled coiled tubing FOECT (3) allowing real-time casing collar locator (CCL) and gamma ray (GR) measurement was used to perform real-time depth correlation for the first time in Saudi Arabia. Using the FOECT results in accurate placement of the slots in the best quality rock.…”

Development and Field Trial of the Well-Lateral-Intervention Tool

“…Lateral accessibility is an important aspect of these concepts of advanced completions. Several meth-ods and tools have been developed to facilitate lateral accessibility from both completion type and tool (Hovda et al 1996;Antczak et al 1997;Rivenbark et al 2000;Dahroug et al 2003;Amorocho et al 2009). However, active sensing and accurate mapping of the lateral window required further improvement through new intervention tools.…”