Study On The Method Of Longitudinal Seismic Data Processing Erdos Basin

The area of Ordos Basin has about25104km2which acrosses the four provinces, Shaanxi,Gansu, Ningxia and Inner Mongolia. It is the second largest oil and gas sedimentary basin ofChina. At present, the total amount of oi in Edorse Basin is more than10billion tons, so ithas become the new successor base of the large-scale integrated energy in China.Nowadays the oil exploration emphasis of Mesozoic in Ordos Basin has turned to theLoess Plateau region in the southern of basin. The seismic and geologic conditions in this areaare very complicated. The surface is coverd by thick loess layer where the thickest loess is upto300m.The deep ravines can be found everywhere that the largest elevation difference is upto600m. The interference waves such as ground wave and refraction wave occured a lot inseismic recordings. The complicated condition of surface causes the severe decline of highfrequency and absorbing of seismic energe. The low ratio of signal to noise and resolution ofseismic data restrict the seismic exploration to take a role in field of the Mesozoic oilexploration. The object layer is the thin reservoir—Mesozoic layer， which has thecharacteristic of low porosity and low permeability，to hard to identify and predict correctly.In order to obtain a high ratio of signal to noise and high resolution of seismic data inrecent years, a set of non-vertical seismic exploration technique aimed at Loess Plateau regionhas been developed gradually after a theoretical argument and a production test started fromfield acquisition.The gather of non-vertical acquistion has wider azimuth and avoid from the near-offsetinterference and the secondary interference of loess that effectively to pressurethe noise toimprove the accuracy of exploration. The technique provides the better seismic data for theLoess Plateau seismic exploration.The non-vertical data processing methods have been varied with the progressing of thetechnique of field acquisition. The technique of non-vertical acquisition have been changed alot. Since2005, some non-vertical acquisition test carried out on few seismic line. In2007, theacquisition of one-source and four-receiver line have carried out for hundreds kilometers. In2008the acquisition of two-source and six-receiver line has produce on the large scale. Maling scrolling non-vertical acquisition in2010and in2011Jiyuan scrolling non-vertical acquisitionin2011were similar with the3D data acquisition. The related processing methods aimed tothe characteristics of non-vertical data have been progressed. On the same investment, theexploration area of application of non-vertical technique is more than triple areas ofconventional2D exploration methods. At the same time, a pseudo3D data can be obtainedby using the certain processing methods. It is means very important for oilfield developmentand seismic data processing.