| Most of the gas-oil bearing basins in the western parts are areas of sophisticated surface and underground structure conditions, whose landforms are mainly desert ^ Gobi and hill land. With the seismic exploration shifting to these fields with poor shooting c onditions, s hooting h as b ecome o ne i mportant factor i nfluencing se ismic acquisition data, while the old shooting methods seem unable. With the development of seismic exploration, the emphasis is transferring to the unobvious and deep layers, so advanced and intensive research of the shooting methods must be made.Shooting and receiving are the two principal factors infiuncing field acquisition quality. As shooting is concerned, the normal shooting methods on plain are paid more attention, while the methods -. mechanism and related technical research which are suitable for the western conditions are little and not systematic or scientific, and they are the obstacles of improving the signal/noise ratio and resolution. The shooting parameters determine the success of the whole project, so it's necessary to develop the western seismic exploration shooting technologies. The following are some principal technical measures:1.All landforms are divided into well shooting and vibroseis shooting. Through the western operating experience digesting the old data and analyzing of different shooting methods on various surface conditions, the primitive understanding of the shooting methods are gained.2.To study of the new techniques and make research of new vibroseis to improve the down-transmitting energy and resolution.Based on the characteristics in the western shooting methods, the following contents are mainly researched:1.To study the past shooting methods and analyze and the situation suitable in this field;2.To research the selective methods based on the western sophisticated surface and underground geological properties, and make use of deduction to analyze the shooting methods;3.With the combination of indoors design and field experiment, to select the shooting source granite characteristics density dynamite type and charge size.4.With the combination of the successful eastern experience and western situations, to study new vibroseis and apply it to practice.Clear wave minim noise disturbance and high s/n ratio are expected, with this prerequisite the wider the valid frequency band, the better it is to make clear the underground geological structure.With analysis of the western surface and underground conditions, a series of experiment and research will be executed and further summarized, to find a series of systematic and valid shooting methods, improve the s/n ratio and resolution and promote the quality of the field acquisition data. |
