Microfacies Individual Sandstone Body Internal Architecture And Remaining Oil Analysis Of East 14th Block

With the constant deepening of field development, looking for remaining oil with scientific and reasonable methods is becoming the theme of the development of oil fields. A solid geological foundation can be made by carrying out researches of detailed oilfield geology, reservoir flow units, and internal architecture of individual sandstone body, thus can provide a basis for looking for the remaining oil.Theories of high-resolution sequence stratigraphy and detailed sedimentology are used in this thesis, to do researches of high-resolution sequence stratigraphy, depositional system ~ sedimentary microfacies of large area infilled well pattern, and reservoir distribution, as well as establishing relevant geological knowledge base. In view of that two-dimensional and intrastratal(rhythmicity of sublayers) heterogeneity of individual sandstone body cannot meet the demands during the period of high water cut stage and tertiary phase, because it not only cannot reveal the spatial variation and distribution of a single sand body's internal physical properties, but also neglected the affections on reservoir heterogeneity of impervious thin-interbeds (most of which are less than 30cm)in an individual sand body; The idea that three-dimensional heterogeneity within a single sand body should be studied according to the reservoir architecture which reflects its origin, forming process and internal structure is proposed. Combining depositional model of single lateral accretion body of meandering stream point bar and its lateral stacking model,"architecture controlled three-dimensional heterogeneous model"of the meandering stream channel sand body in which"crescent wedge-shaped lateral accretion bodies, in which permeability decreases upward and to the convex shore, are diagonal and lateral stacked one by one, and are isolated by impervious lateral accreting thin-interbeds". Impermeable thin-interbeds and their shelter-barrier frame which was neglected before but is utmost important to internal three-dimensional heterogeneity of single sand body is revealed. And thus the basic unit of internal physical properties of a single sand body(lateral accretion sand body) and its three-dimensional distribution law are revealed objectively. So the essence of internal three-dimensional heterogeneity of a single sandbody is reflected, and great impact can be produced to internal seepage field of a single sand body, formation and distribution of injectant displacing oil and remaining oil. There will be great significance to study and prediction of remaining oil during high water cut stage, tertiary oil recovery phases and posterior period.