Glutenite Reservoir Prediction Research In Yan22 Block Of Dongying Depression

Glutenite bodies occured along the edge of steep slope belt of continental basins, which were special sedimentary bodies with rapid accumulation,retrograding product. It is widely distributed in continental basins, which superimposed in vertical, and the lithology changes quickly in horizontal. In recent years, along with the improvment of exploration technologies, the hydrocarbon reserve of glutenite bodies increased every year, and it is paied more attention to this kind of reservoirs. The reservoirs of Deep glutenite bodies in ShengLi oilfield mainly distribute in"two steep belts", which are called CheZhen north part and DongYing north part. Since the Tenth Five-Year, the proportion of its reserve in annually increased reserve increased more and more. The glutenite bodies were superimposed by many period of debris rocks, which changed quickly in horizontal, buried deeper in vertical (usually more than 3000m) and complicated inside. And its reservoir space display rules are unclear. The factors mentioned above hampered the development of this kind of reservoir.Due to the seismic wave propagated far and energy attenuated in the course of propagation with high frequency absorption and the complicated wave, the seismic data in deep depth has a low resolution and low signal-to-noise ratio, which restricted the precision of reservoir prediction. This paper treated glutenite bodies'reservoir in Yan22 block as the research object. Before the prediction, it is based on the well-constraint processing method to enhance seismic frequency and broaden frequency band of seismic data. Using stochastic optimization seismic inversion to predict various periods of glutenite bodies distribution, according to stochastic optimization seismic inversion using probability density function as a constraint, the calculation is easy and very stable no matter the block of more wells or less wells. In addition, based on moving the seismic window,it is to calculate the variance of subsection which is the distribution of wave impedance. Having 7 vertical wells in yan22 block and directly using the statistical extremum as space constraint, random algorithm is applied to calculate impedance sequence considering both stochastic characteristics and seismic response. Through this inversion method, it is obtained of the three-dimension impedance data in yan22 block , which is a ground to determine each glutenite body speed ,petrophysical parameter and impedance parameter to establish forward model. Under the guid of the basic geological rule, at the same time to consider the data (such as drilling, coring and sedimentary structure etc), it is to conduct interactive inversion and partly modify forward model. After that the forward model is used as constraint conditions to iterative inversion, finally it will get more accord with geological rule. The inversion method applied in yan22 block has received good effect, the inversion result is more reasonable. By using this method to predict reservoir in yan22 block,glutenite bodies is divided to nine times and each glutenite body have the thickness from 40 to 80 meters.