Executive Summary

Dean Wehunt, Chevron Business Development

I’m looking forward to serving as the new Executive Editor for this journal. Because this is a technical journal and you paid money, let’s get right to the heart of the matter.

This edition of SPEPO contains 10 peer-approved technology papers for your review. In homage to the great film Casablanca, we first "round up the usual suspects" with three papers on hydraulic fracturing, specifically about measuring or predicting fracture growth. Hydraulic Fracture-Height Growth: Real Data should become a standard reference for all parties seeking to understand how hydraulic fracturing may impact groundwater resources. This paper provides an extensive review of fracture-height-measurement data in multiple North American basins using microseismic or microdeformation-monitoring techniques, and also includes an enlightening discussion of numerous fracture-growth-limiting mechanisms. The next paper, Hydraulic Fracture Crossing Natural Fracture at Nonorthogonal Angles: A Criterion and Its Validation, is an important advance in forecasting the degree of fracture complexity that will result from treating naturally fractured formations. Using Real-Time Downhole Microseismic To Evaluate Fracture Geometry for Horizontal Packer-Sleeve Completions in the Bakken Formation, Elm Coulee Field, Montana is a case study illustrating how fracture-geometry measurements have improved hydraulic fracturing and completion practices and also production results in the Elm Coulee field.

Next, we have a paper about conformance optimization using inflow-control devices. Inflow-Control-Device Design: Revisiting Objectives and Techniques discusses an ICD design method based on permeability and wellbore friction and shows an example of how production can be suboptimized in most wells if the goal is to achieve a uniform flux profile.

We have three interesting papers about coiled-tubing applications. From Operations to Desktop Analysis to Field Implementation: Well and ESP Optimization for Production Enhancement in the Cliff Head Field has something for everyone. This interesting paper discusses integrated production modeling, surveillance, and optimization for a field with coiled-tubing-deployed electric submersible pumps. A case study about a challenging application is presented in Pushing the Boundaries of Concentric-Coiled-Tubing Technology To Resurrect Subhydrostatic Gas Wells on an Unmanned Offshore Installation. This offshore field had horizontal wells with proppant accumulations in large-diameter tailpipes that were preventing the wells from flowing. They were able to clean out the wells and hang velocity strings across the tailpipe sections without using a conventional rig. Inversion of Distributed-Temperature-Sensing Logs To Measure Zonal Coverage During and After Wellbore Treatments With Coiled Tubing shows a procedure to develop quantitative fluid-injection profiles by using distributed temperature sensing deployed in coiled tubing, with the goal of rapid evaluation and changing the diversion profile for the remaining stages.

Finally, we have three heavy-oil papers. Critical Oil Rate and Well Productivity in Cold Production From Heavy-Oil Reservoirs provides methods to determine the critical minimum flow rate necessary for continuous removal of sand from a horizontal heavy-oil well, well productivity as a function of cumulative sand production, and tubing friction caused by four-phase flow (oil, water, gas, and sand).These calculations are needed to predict performance of different well designs and make critical decisions such as horizontal well length and designing artificial-lift systems. This edition contains a second paper regarding performance of heavy-oil wells considering the effect of entrained gas. Well-Performance Relationships in Heavy-Foamy-Oil Reservoirs shows how to account for entrained gas and also demonstrates that performance models neglecting this effect for foamy oils will under-predict well performance. Application of the Bergman-Sutton Method for Determining Blend Viscosity provides a method to estimate the viscosity of hydrocarbon blends without first measuring the viscosities of the blend components. All that is required is component specific gravity, Watson characterization factor (Watson "K" factor), and temperature. The paper also defines new mixing rules that should be used with this correlation. Although this paper is not merely applicable to heavy oil, it will be particularly valuable during assessment and design of projects requiring blending to transport heavy crudes.

I hope you will find these latest SPE Production & Operations journal papers both interesting and valuable to your business activities, meeting your demand for high-quality papers that document the best and brightest new production and operations technologies within our industry from around the world.

Last month, outgoing Executive Editor Jennifer Miskimins did a great job of thanking the SPE publications staff, the small army of industry volunteers that make up the technical editing staff, and the SPEPO readers. I add my own thanks to Jennifer and the SPE publications staff for helping me during my transition into this EE role. I am humbled and I feel grateful for the opportunity to serve SPEPO readers and our society in this way.