Research On Distribution Of Gas-Water In The Daniudi Gasfield

Daniudi gas field shan 1 gas reservoir is a lithologic gas reservoir in the low amplitude structure. Its reservoir with the characteristic of complicated reservoir spreading, it also has a feature of poor reservoir physical property which represents in low porosity and permeability, high water cut and strong heterogeneity in both vertical and horizontal. All these result in low productions, producing water and the hard hydrops. Based on the predecessors'research of Daniudi gas field shan 1 gas reservoir, regional geological characteristics, water analysis, logging interpretation and test data, this article researches the producing water pattern, gas-water distribution laws, the geological factors of controlling gas-water distribution. Basing on the geological and exploitation data available, analyzing water chemical materials and dynamic analysis were combined in this study, which led the following results:(1) Researching on Daniudi gas field shan 1 gas reservoir's sand bodies, intercalated bed, and physical properties of reservoirs distribution, we have acknowledged shan 1-2 single layer's sand bodies thick and steady development, and better than shan 1-3 and shan 1-1, along the river sand body has a good connectivity, sand body distribution is controlled by sedimentary microfacies; intercalated bed is thin and widespread; low porosity and permeability, most of it were controlled by poor physical properties of reservoirs; the place with thick sand bodies and Intercalated bed has low gas saturation and high water saturation.(2) Analyzing systematieally logging features of reservoir in the studied area, identifying the reservoir fluid through Logging cross-plot, making sure the water distribution. By studing the chemistry laws of water, we know the type of water of Daniudi gas field shan 1 gas reservoir is CaCl₂ and original remain water, combining water and dynamic analysis, we think the poor migrated energy of gas maded the high water saturation in the reservoir, result in the well produce more or less water.(3) Classifying the gas well by the number and the tendency of producing water, and calculating the condensate water through the Mcketta-Wehe calculating chart, we know 1 ten thousand square gas produce 0.06-0.08 square condensate water, in the study area the water yield of single-well is greater than the number of condensate water, the water of gas well is the formation water, so we think the formation water of gas well is made of condensate water, freedom water and bound water.(4) Combined the test results of logs interpretation, test and production data and ground water test and analysis data, with the thickness chart of sandstone bodies and distribution chart of porosity and permeability and three profile picture of gas-water distribution, research on the ground water distribution laws, so we know the ground water of shan 1 reservoir have the feature of discontinuous and scattered distribution, it is different the distribution laws of gas reservoirs with edge water and bottom water. Gas-water distribution is controlled by sand body, intercalated bed and reservoir physical propert, the place which has thick sand bodies, has a good reservoir physical propert, a high gas saturation and a low water saturation, high producing gas and low producing water.