Re-calculation On The Reserves Of Dalaoyefu Oil And Gas Fields

With the deepening of exploration and development, the phenomenon of mismatch between geological reserves and development index in some parts of oil field is increasingly prominent. Statistical on geological reserves re-calculation(volume method) of 56 oil fields and 94 fault blocks declared after 1984 show that geological reserves differs very large before and after re-calculation, errors distribution of different fields are mainly concentrated in between 6% ~ 72%. The causes of errors including:(1) Incomplete and inaccurate of basic information;(2) insufficient of research;(3) unreasonable of parameter method determining. How to improve the calculation accuracy of geological reserves is a serious issue to oilfield development workers.The development of Dalaoyefu oil and gas field began in 1996, now it has entered late development stage. In this paper, geological characteristics, sedimentary, reservoir characteristics, distribution and types of reservoir in Daloyefu oil and gas field were further researched. And reservoir geological understanding of Daloyefu oil and gas fields are completed. On this basis of the understanding integrated interpretation of the logging data, the average porosity and oil saturation are determined. Meticulous division of the cells in the researching layer. On the basis of comprehensive research on reservoir and combines with the test results confirmed the oil-bearing area. In the basis of core, logging, wall coring data, created relationship using testing data and logging data, divided effective thickness for single well according to the standard, and on the basis of the predecessors’ research results and the experimental method to determine the density of crude oil, crude oil volume factor, formation temperature, initial pressure and the gas cap gas deviation factor parameters, re-calculate reserves of Dalaoyefu oil and gas fields using volume method. Reserves re-calculation results are as follows:The formation superimposed petroliferous area of K1qn1 and K1q4 of Dalaoyefu oil and gas field is 39.47 km2, and geological reserves of oil is 2599.61×104 t(2984.43×104 m3), technical recoverable reserves of oil is 319.75 ×104 t(367.07×104 m3). Geological reserves of dissolved gas is 14.18×108 m3, echnical recoverable reserves of dissolved gas is 5.66×108 m3. Bearing area of composite gas is 13.10 km2, geological reserves of gas-cap gas is 4.61×108m3, technical recoverable reserves is 3.47×108 m3.