Xinjiang Petroleum Geology ›› 2020, Vol. 41 ›› Issue (6): 704-708.doi: 10.7657/XJPG20200610

• RESERVOIR ENGINEERING • Previous Articles     Next Articles

Theoretical Perfection and Application of Tong’s Curve Chart

CUI Yinghuai1(), HUI Huijuan1, SHENG Han2, GAO Wenjun1   

  1. 1. Research Institute of Exploration and Development, Tuha Oilfield Company, PetroChina, Hami, Xinjiang 839009, China
    2. EnerTech-Drilling & Production Co., CNOOC Energy Technology & Services Limited, Tianjin 300452, China
  • Received:2020-04-09 Revised:2020-08-06 Online:2020-12-01 Published:2020-12-02

Abstract:

Tong’s curve chart is the primary method for calibrating recoverable reserves in water-flooded oilfields. As water-flooded reservoirs in China produce more and more water one after another, the relationship between recovery percent and water cut in many reservoirs is becoming inconsistent with Tong’s curve. In this paper, on the basis of new seepage characteristic equation, we derive the general formula of Tong’s curve by using Welge equation, and improves the theoretical basis of Tong’s curve. Under certain conditions, the general formula of Tong’s curve can be converted into the typical Tong’s curve and its improved formula, and its corresponding water drive characteristic curve can be converted into Maksimov water drive characteristic curve. Since it can correct Maksimov water drive characteristic curve and Shadrov water drive characteristic curve, the general formula of Tong’s curve is more adaptable under certain conditions. Taking the reservoir of the Sanjianfang formation in Qiuling oilfield as a case, the methods for building actual Tong’s curve and determining reservoir characteristic parameters are proposed.

Key words: Tong’s curve chart, water-flooded reservoir, seepage characteristic, water drive characteristic curve, derivation, application

CLC Number: