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Continuous development and rapid deployment of new thermal technologies are critically important in the quest to make heavy oil projects cost competitive. Worldwide heavy oil deposits are abundant, but conventional development schemes may not be financially competitive. Currently, oil companies have a multitude of new investment opportunities, which further stresses required funds available for the continued development of new and existing heavy oil assets. How can heavy oil assets compete financially? New, cost effective technologies must be developed and deployed to improve the margins of heavy oil assets. An effective partnership must be maintained between the technology developers and the technology users to ensure a smooth transition from concept to field test to commercial application. The alignment of technology development to the real business needs is essential. This paper reviews a portfolio of new heavy oil technologies that Texaco is pursuing alone and in partnership with other companies. The processes used to assure business alignment, technology transfer, and deployment are also discussed. The heavy oil and thermal technology development portfolio includes novel steam generation, improved steam delivery (measurement and distribution), and aggressive heat management projects. These new surface and sub-surface heavy oil technologies will be discussed relative to the potential impact that they could have on several existing and new heavy oil fields. Heavy Oil Resources Heavy oil resources are abundant. In fact, heavy and extra heavy oil resources are estimated to be more than 2.5 trillion BO. The vast resources of the Orinoco and Canada extra heavy oil or bitumen regions are well documented1,2, and offer large targets for in-situ and surface development techniques. Potential recoverable heavy and extra-heavy is projected to be 856 MMBO with current technology.3 There is no shortage of heavy and extra heavy oil in the world today. The challenge is how to produce this resource profitably. An energy resource that will play a large role in our future. Thermal Recovery, The Current State-of-the-Art Thermal recovery continues to be an attractive means of maximizing the value and reserves from heavy oil assets. The successful application of thermal recovery techniques has maintained worldwide thermal production rates at 1.3 MMBOPD4–5, and Texaco's thermal operations represent a significant portion of the worldwide total. Texaco's vast steamflood operations centered in California and those of its affiliate PT Caltex Pacific Indonesia together produce approximately 450 MBOPD as shown in Fig. 1. Heavy oil assets, such as the Kern River field, demonstrate how important steamflood technology is to heavy oil recovery. Prior to the implementation of thermal operations, the Kern River field was producing approximately 10MBOPD. Following the fieldwide implementation of steamflooding, the Kern River field has produced in excess of 120MBOPD for the last two decades (Fig. 2). This is one of the true success stories for thermal recovery.

The Kern River Field is a large, shallow, heavy oil reservoir located five miles northeast of Bakersfield, California. Both reservoir and fluid characteristics are very favorable for thermal recovery methods. The unconsolidated oil sands exhibit high permeabilities of 1–5 darcies (1–5 μm2) and porosities of 28–33%. Reservoir pressure is low, averaging 100 psig (690 kPa). Oil viscosities average 4000 cp (4 Pa ·s) at reservoir temperature and drastically reduce at elevated temperatures. Previous articles1,2,3,4 have been published concerning steamflood pilot design and behavior in the Kern River Field. This paper updates previous articles with a review of 263 steamflood patterns started in 1970 and 1971. The effects of sand thickness, completion interval and heat injection rates on steamflood recovery will be analyzed. Effective project evaluation through the use of temperature observation wells, coring, casingblow measurement and production from wells completed solely in the steamflood interval is emphasized. Problems of evaluating steamflood performance in amulti-zone reservoir are discussed and two field tests for improvement of steamflood sweep efficiency are also presented. Introduction Getty Oil Company attempted the first steamflood pilot in the Kern River Field in 1964 with four inverted 5-spot patterns on the Kern property in the center of the field, as shown in Figure 1. The design and results of this pilot proved successful as reported by Bursell.2,3 In 1968 and 1969, eight additional steamflood pilots were installed in the Kern River Field to evaluate the steamflood response of other oil sands in different locations within the field. The successful response of these nine to twelve pattern pilots led to the first major expansions in 1970 (189 patterns) and 1971 (325 patterns). The initial steamflood is now complete or is approaching completion in these early expansions, and results of these projects will be analyzed within this paper. Through the use of coring, temperature observation wells, production from wells completed solely in the steamflood interval, and casing blow measurement anaccurate evaluation of actual steamflood performance is attempted. Post displacement coring in the pilot steamflood projects revealed poor vertical sweep efficiency which led to two different field tests to improve sweep efficiency within the 1971 expansion projects. A review of the two field tests is presented. Field Description1 The Kern River Field reservoir is comprised of the Kern River Series sands. The Kern River Series consists of an alternating sequence of unconsolidated sands with considerable interbedded silts and clays. A typical cross-section of the various sands is shown in Figure 2. The four main oil sand intervals are defined (C, G, K and R) and can be correlated across the entire field. The sub-divisions of the main intervals comprise the steam displaceable zones which range in thickness from 25 to 125 feet (7.6 to 38.1 m). These sands characteristically exhibit 30% porosity and 1–5 darcies (1–5 μm2)permeability. Structure of the Kern River Field is a simple homocline dipping at 3–6 ° to the southwest. The updip oil sands pinch out and the productive downdip area isbound by an oil-water contact. Oil sands are present at depths of 400–1,400 feet (122–427 m). Produced oil gravity varies across the field from 9 ° to 16 ° API. Corresponding viscosities also vary greatly from 10,000 to 600 cp (10.0 to 0.6Pa ·s) at 100 °F (38 °C). Heat very effectively reduces the viscosity of the Kern River crudes. Typically there is a 100 to 500 fold decrease in viscosity at 250 °F (121 °C) which is the reason of the success of thermal operations in heavy oil. Field Description1 The Kern River Field reservoir is comprised of the Kern River Series sands. The Kern River Series consists of an alternating sequence of unconsolidated sands with considerable interbedded silts and clays. A typical cross-section of the various sands is shown in Figure 2. The four main oil sand intervals are defined (C, G, K and R) and can be correlated across the entire field. The sub-divisions of the main intervals comprise the steam displaceable zones which range in thickness from 25 to 125 feet (7.6 to 38.1 m). These sands characteristically exhibit 30% porosity and 1–5 darcies (1–5 μm2)permeability. Structure of the Kern River Field is a simple homocline dipping at 3–6 ° to the southwest. The updip oil sands pinch out and the productive downdip area isbound by an oil-water contact. Oil sands are present at depths of 400–1,400feet (122–427 m). Produced oil gravity varies across the field from 9 ° to 16 ° API. Corresponding viscosities also vary greatly from 10,000 to 600 cp (10.0 to 0.6Pa ·s) at 100 °F (38 °C). Heat very effectively reduces the viscosity of the Kern River crudes. Typically there is a 100 to 500 fold decrease in viscosity at 250 °F (121 °C) which is the reason of the success of thermal operations in heavy oil.

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