Study On Integrated And Optimum Forecasting Model Of Tertiary Reservoir In Jiyan Depression

Jiyang depression is located in Bohaiwan basin, where hydrocarbon-bearing tertiary sequences is widely distributed and has multiple types of reservoirs. After more than40years’exploration, Jiyang depression is coming into mid-later stage of exploration, at present,80%of the reservoirs added each year are from stratigraphic, lithologic and complex buried-hill traps. So the exploration depends greatly on the techniques of seimic-based delicate forecasting, description and evaluation on resevoirs. However, nowadays seismic reservoir forecasting is usually done for a definit object, the general and systemic methods of seismic reservoir forecasting is rarely reported. With the increasing of exploration extent, the exploration object is more and more complicated and hiding, the current techniques of reservoir forecasting is not enough for the practice need, deepening study on reservoir forecasting is badly needed. This paper focuses on the optimal and integral method of reservoir forecasting in order to decrease the uncertainty of reservoir seismic forecasting and increase the probability of success for drilling.The major results of this paper are as follows:1. Systematic summary of the sedimentary characteristics and reservoir distribution of the tertiary reservoir in Jiyang depression, building a basic relationship between the sedimentary facies and lithologic, physical nature.2. According to the study on reservoir condition and feasibily of forecasting techniques, this paper set up the optimal combination of different forecasting technologies to meet the requirement for the forecasting of rock facies, lithology, physical nature and formation liquid.3. Concerning the validity of reservoir forecasting, this paper studed on the feasibility of reservoir forecasting and evaluation techniques, point out that the reservoir forecasting dependes on the size, rock physical parameters, and quality of seismic data of the reservoir, built the system for reservoir forecasting and evaluation. Originally developed a method for the validation evaluation of reservoir forecasting techniques based on risk probability, artificial neutral net and specialists system. This method makes it possible for quantitative evaluation of validity of reservoir forecasting by size, rock physical characters, lithological combination and seismic data quality.4. Concerning the model and integration for seismic reservoir forecasting, this paper developed an integral forecasting technology for typical reservoir types such as fluvial sandstone, turbulent sandstone, shoal and bar sandstone and fan gravel stone.8models are built for reservoir forecasting:low-sand/mud-ration for fluvial sandstone; high-sand/mud-ration for fluvial reservoir; sub water fan; basin bottom fan; collapsed turbulence sandstone; multiple-material-sources turbulence sandstone, and thin interbeds sandstone.