In the northern part of Erzhong District in Karamay conglomerate oilfield, Xinjiang, China, ASP pilot tests have been conducted in 13 wells in a pilot area of 0.031 square kilometers since September 1994. The pilot area was developed through combining laboratory results in recent years with specific conditions in the field. This test is aimed to verify oil displacement efficiency of ASP and related reservoir behaviors, to improve production techniques necessary to obtain remaining oil from conglomerate reservoirs, and to provide data for economic feasibility evaluation. P. 385

It is estimated that the ultimate oil recovery by waterflooding is not more than 25% in conglomerate III reservoir in Karamay oilfield due to high crude oil viscosity and poor development effect. Therefore, it is found that the development effect and oil recovery can be significantly improved by steam injection because this kind of conglomerate reservoir is characterized by shallow burial, relatively concentrated oil layers and good connectivity. Based on the thermal drive experiments in laboratory and numerical simulation, about 24% and 20% incremental oil recovery can be achieved by conversion into steamflood respectively. Excellent development effect has been gained with an average production of 951 tiwell within a stimulation cycle, daily production of 4.2t/d per well, cumulative OSR of 0.355, production rate of 3.5%, all of which have reached the designed indexes. It is proved that, for conglomerate reservoirs like type 111 in Karamay oilfield, conversion into steam stimulation at the late waterflooding stage is an effective way to improve its development effect. P. 179

Electronic reproduction, distribution, or storage of any part of this papr for commercial purposes without the written consent of the Society of petroleum Engineers is pmti~ted. permission lo. reproduce in print is restrided to an abstract of not more than 300 wordq illustrations may not be copied. The abstract must contain conspicuous acknowledgment of wtire and by whom the paper was presented. Write Librarian, SPE, P.O Box 833836, Rchardson, TX 75083-3836, U. S. A., fax 01-972-952-9435. AbstractBased on the study of remaining oil distribution and detailed reservoir description, the design optimization and field test of sidetracking horizontal drilling (SHD) in Xinjiang conglomerate reservoirs has been done. Single well production rate of two SHD wells is 2-3 times that of the average rate in the test area.That shows the technique can improve development effect of the conglomerate reservoir at mid-high water cut stage. Accurate geological description and reservoir engineering study are the key factors to the success of SHD, and to select a proper completion method is also important for the development of old field with complicated multi-bed sets. The application of SHD is limited in small ranges with small formation penetrating thickness. Therefore, we present a modified concept for the development of the aging field, SHD takes the leading role while conventional horizontal drilling and vertical drilling are the supplements.