Both conventional and non-conventional well testing and sampling operations require some form of design a priori. Due to the uncertainties in input parameters during the test design stage, test sequence and duration are mostly adhered to especially when memory gauges are being used. These uncertainties are more pronounced during exploratory or appraisal testing; hence, being able to make adjustments throughout the testing operation can result in significant value creation, particularly when operating in a high cost deep water environment. This paper describes how real time pressure transient analysis (RT-PTA) may be used to optimize test sequence and duration in exploratory well testing and sampling. Two case histories are presented that show the impact and value added by combining real time data acquisition, analysis and decision making in the test procedure. Value is achieved by making informed decisions to redesign the test sequence to better meet test objectives, improved stakeholder communication concerning the reasons for these changes and improvements in contingency planning. It is the authors' hope that these examples will be useful to our peers when engaging in Value of Information (VOI) discussions. Several modes of deployment currently exist for downhole data acquisition and transmission to the surface in real time. Case histories showing results from the application of two of these deployment techniques are presented. While no effort has been made to demonstrate the superiority of one method over another, emphasis has been placed on the impact of enabling real time monitoring and analysis of data acquired during well testing operations. The two methods presented, tubing encapsulated cable (TEC) and an acoustic telemetry system (ATS), were deemed most appropriate for each specific application. The suitability of this approach for conventional and non-conventional well testing and sampling, the ability to adapt this technique to different types of tests and of being able to revise test sequence in real time to more efficiently accomplish a given set of goals makes real-time pressure transient analysis (RT-PTA) very attractive.

Artificial lift systems have encountered traditional challenges in the production of high viscosity oil-well fluids such as heavy and extra heavy crudes. These challenges included problems with sand abrasion, formation of emulsions (fluid shearing), high wellbore deviation (horizontal wells), scale deposition, and temperature and fluid rate limitations. The development of ESPCP technology meant the synergy of PCP and ESP into a hybrid that takes advantage of the best qualities from both worlds. On one end, ESPCPs offer greater resistance to solids abrasion (solids production), high viscosity liquid production capability (positive displacement pump) and the low fluid shear characteristics of PCPs. On the other end, ESPCP systems may be deployed in high deviation wellbores, while still able to provide the substantial liquid rates and torque derived from ESP down-hole motors. The exploitation of unconventional resources, such as heavy oil thermal projects, has triggered the development and improvement of ESPCP technology for high temperature applications. In particular, the use of ESPCPs in heavy oil steam flood reservoirs with cyclic steam stimulation, such as in the well known Kern River field, poses a significant challenge to this artificial lift system. This paper describes the experience and results of the first ESPCP pilot project known to the authors, where all parts of the subject unit are exposed to short, but direct cycle steam stimulation treatments.

TX 75083-3836 U.S.A., fax 01-972-952-9435. AbstractThis work presents the well-test management design and interpretation methods that have been implemented to evaluate the exploratory wells of the Plataforma Deltana Project, in the Eastern Venezuela basin. The proposed methodology has been applied to an exploratory well drilled in this project, it is an offshore gas-condensate well located near the border of Venezuela and Trinidad & Tobago. One important aspect that is emphasized in this work is the need to test exploratory offshore wells to obtain the basic reservoir and well productivity parameters, and to provide an estimate of the recoverable reserves associated to the well drainage area. The methodology is based on the integration of seismic, geology and petrophysical information, to optimize the design and time of the tests. In order to elaborate the particular well testing program in the best economical way, time is a critical factor in any offshore well, in addition to get focused on layer evaluation and determining producing fluids properties. In this work the evaluation results obtained from the implementation of this methodology in two sands is presented.

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