Study Of The Slope Fan Within The Delta Front Using Sedimentary Simulation Experiment

As a new stratigraphic reservoir,slope fan contains rich oil and gas resource and holds large exploratory potential.Since year 2009,Shengli Oil Field has arranged several wells aimed in slope fans,and almost 80 percent of which were succeed in finding oil and gas and displayed good petroleum condition during the subsequent develop process.However,to present the study of slope fan is still in the initial stage and there has been very few researchers studying such project.Due to the good exploratory potential,the necessity of being researched should be noticed.Through this thesis,previous researches were concluded,further research was made.The differences has been pointed out between the slope fan and the slip turbidite fan.Besides,based on the research about the forming environment of the Dongying Delta,parameters which can reflect the original condition of Dongying Delta were designed.Using such physical sedimentary simulation experiments,the formation process as well as the main factors which affect the slope fan were reconstructed.All these researches will contribute to a deep insight into the slope fan in order to provide a useful theory to the exploration and development of such oil and gas reservoirs.Slope fan is a type of sudden deposits which is triggered by the influences such as earthquake and wave etc.,such condition breaks the stability of the sand bodies of the delta and fan delta,the sand bodies separate away by the way of slide,slump or debris flow,and finally deposit again along the ramp.Slope fan has great difference from the slip turbidite fan in terms of the lithology,grain size,sedimentary texture,longitudinal sequence(cyclicity),seismic reflection as well as the well-logging response.Deep understanding of these differences is very helpful for distinguishing these two geologic subjects.According to the similarity principle,physical sedimentary simulation experiments are conducted using the variate controlling method.As a result,three types of formation process of the slope fan are concluded including the lateral expanded slope fan along the fan-fringe,longitudinal expanded slope fan from lake to land and the random expanded slope fan which has no patterns.Seven types of slope fan exist according to the transport mechanism including the slid slope fan,slump slide fan,debris flow slope fan and their combinations(slid-slumpdebris flow,slid-slump,slump-debris flow and slid-debris flow).The factors which affect the slope fan can be summarized in the degree of consolidation,trigger mechanism(earthquake,wave and the water level falling),ramp gradient,the uneven degree of the ramp,as well as the scale of the delta(which may affected by the water flow and water depth).