SU958999A1

SU958999A1 - Seismic wave excitation method

Info

Publication number: SU958999A1
Application number: SU782523985A
Authority: SU
Inventors: Валерий Вильгельмович Циммерман
Original assignee: Специальное Конструкторское Бюро Сейсмической Техники
Priority date: 1978-09-14
Filing date: 1978-09-14
Publication date: 1982-09-15

Description

Изобретение относитс к способам возбуждени сейсмических волн в сейсморазведке, а именно к способам возбуждени , основанным на использовании энергии падакнцего груза .The invention relates to methods for exciting seismic waves in seismic exploration, and in particular to methods of excitation based on the use of the energy of the padacan cargo.

Известен способ возбуждени сейсмических волн с использованием энергии падающего груза, по которому грузмассЬй в несколько тонн поднимаетс на определенную высоту над поверхностью Земли и фиксируетс В момент прихода с блока управлени запуркающей команды груз освобождаетс , падает и, удар сь о грунт, возбуждает в нем сейсмические волны 1. ..A known method of exciting seismic waves using the energy of a falling load, according to which a weight of several tons rises to a certain height above the Earth's surface and is fixed. At the time of arrival from the control unit of the storing command, the load is released, falls and, striking the ground, excites seismic waves in it one. ..

Недостаток этого способа .заключаетс в том, что.непосто нство времени падени груза от одного воздействи к другому, возникающее в результате неточности высоты подъема . груза, неровностей грунта и др./ це позаол ют синхронизировать момент начала силового воздействи источника с запускающей командой, и,следовательно , не позвол ют использовать эти источники при методах сейсморазведки , основанных на суммировании отражений волн, возбужденных несколь-.The disadvantage of this method lies in the fact that the instability of the time of the fall of the load from one impact to another, resulting from the inaccuracy of the lifting height. The load, uneven ground and others. The center will synchronize the moment of the beginning of the force action of the source with the launch team, and, therefore, do not allow using these sources for seismic surveying methods based on the summation of reflections of waves excited by several.

кими сейсмическими источниками одновременно или последовательно. Из-за нестабильности времени падени временной интервал между запускающей командой и моментом начала силового воздействи непосто нен, в результате чего отраженные волны поступают в суммирующее устройство с раз чными сдвигами фаз ,что приводит к искажению-. seismic sources simultaneously or sequentially. Due to the instability of the fall time, the time interval between the triggering command and the moment of the beginning of the force action is not constant, with the result that the reflected waves enter the summing device with distinct phase shifts, which leads to distortion.

10 принимаемой информации.10 received information.

Наиболее близким к предлагаемому по технической сущности и достигаемому эффекту вл етс способ возбужде 5 ни сейсмических волн посредством силового воздействи падающего груза на грунт, включающий установку опорного устройства, подъем груза и сброс его в момент подачи команды запускаThe closest to the proposed technical essence and the achieved effect is the method of initiating 5 seismic waves through the force effect of a falling load on the ground, including the installation of a support device, lifting the load and dumping it at the moment of launch command

20,на опорное устройство.20, on the supporting device.

Массивный ivy3 поднимаетс с помощью электромагнитов. Высота подъема груза регулируетс , что позвол ет скорректировать врем падени груза The massive ivy3 rises with the help of electromagnets. The height of the load is adjustable, which allows you to adjust the time of the load falling.

25 дл обеспечени совместной работы нескольких установок 2.25 to ensure the joint operation of several installations 2.

Claims

The disadvantages of the method are that the load falling time is still unstable and depends on external conditions. In addition, this method does not allow to adjust the temporal and power characteristics of the effect. The aim of the invention is to increase the seismic efficiency of the method by increasing the accuracy from 1 time to the beginning of the power action with the start command. . This goal is achieved by the fact that in the method of exciting seismic waves by means of a force effect of a falling load on a load, including the installation of a support device, the load is lifted and dumped at the time of launch command, after a given time command, the start command is given to brake. the falling load relative to the supporting device and the force effect of the load on the ground is carried out through the supporting device. During braking, the support device through the llit contacting with the ground exerts a force action on the ground and excites this cosmic wave in it. Since the processes of braking the incident load and the force effect of the supporting device on the ground are interrelated, it is possible with the help of the brake device to control the moment of the beginning of the force / action. If the braking torque is associated with the command of the control unit, then neither the difference in lift height, nor the instability of the time of the fall of the load, nor other external factors. conditions will not affect the timing of the source. Moreover, by changing the characteristics of the braking device, it is possible to control the duration and form of the force effect. The proposed method can be implemented, for example, with a working-seismic source, in which a massive load-drummer, made of a soft material magnet and able to slide along guides inside a pipe, is placed inside a pipe installed on the ground. A series of coils of electromagnets is placed along the pipe from the outside of the tube to which an electric current is supplied through a special device. With the help of electromagnets, the fall of the load is accelerated and it is lifted to its original state. DP work on the proposed method is necessary to carry out the following sequence of operations. The drummer rises to its original position and is fixed. Upon command from the control unit, the striker is released, falls and is additionally accelerated by electromagnets. After a certain period of time (before the striker reaches the ground), the electrodes are sharply braked by means of electromagnets. As a result of braking the pipe with electromagnets attached to it, a force is applied to the ground and a seismic wave is excited in it. The inconstancy of the fall time of the load, which could have arisen as a result of variations in the magnitude of the acceleration force, friction forces, and other reasons, is completely excluded when using the proposed method. The application of the proposed method allows, when conducting seismic exploration by the method of summing reflections of a series of seismic waves excited by one or a group of seismic sources, to use devices for exciting seismic signals based on the use of the kinetic energy of a freely incident and additionally accelerated impact body, different simplicity and high efficiency. Claims The method of exciting seismic waves by the force of a falling load on the ground, including installing a support device, lifting the load and dumping it at the time point of the launch command, characterized in that, in order to increase the seismic efficiency of the method by increasing the accuracy of the synchronization of the beginning. a force action with the start command, after a specified period of time after the start command, a command is issued for braking the incident load relative to the supporting device and the force action e is performed on through, the support apparatus. Sources of information taken into account in the examination 1. US patent 2851.R21, class. 01 V 1/14, published. 195.8.

2. US patent 3.393763, cl. C 01 V 1/04, published. 1968 (prototype).