SU534720A1

SU534720A1 - Source of seismic signals for water areas

Info

Publication number: SU534720A1
Application number: SU2070251A
Authority: SU
Inventors: Владимир Александрович Ежов; Владимир Данилович Москвичев; Владимир Карпович Мейстер; Владимир Герасимович Широкий; Даниил Федорович Линчевский
Original assignee: Южное Морское Научно-Производственное Геолого-Геофизическое Объединение "Южморгео"
Priority date: 1974-10-29
Filing date: 1974-10-29
Publication date: 1976-11-05

Description

ИСТОЧНИК СЕЙСМИЧЕСКИХ СИГНАЛОВ SOURCE OF SEISMIC SIGNALS

(54) ДЛЯ АКВАТОРИЙ(54) FOR AQUATORIES

Изобретение относитс к морской сейсморазведке , в частности к устройствам, создающим акустические сигналы в воде за счет детонации водородно-кислородной газовой смеси.The invention relates to marine seismic exploration, in particular, to devices that generate acoustic signals in water due to the detonation of a hydrogen-oxygen gas mixture.

Известны источники волн на акватори х, в которых используетс детонаци водород- но-кис лор одной смеси 111.There are known sources of waves in water areas that use the detonation of hydrogen – acid mixture of one mixture 111.

При подводном взрыве газовой смеси возникают две основные волны давлени : перва волна - от расшир ющихс продуктов взрыва, втора - от схлопывани продуктов взрыва, причем втора волна несет более полезную сейсмическую энергию. Однако при использовании взрывчатых газовых смесей заглушить первую волну давлени и использовать только вторую практически невозможно , а использование первой и второй волн вместе затрудн ет интерпретацию сейсмограмм .During an underwater explosion of a gas mixture, two main pressure waves arise: the first wave, from the expanding products of the explosion, and the second, from the collapse of the products of the explosion, with the second wave carrying more useful seismic energy. However, when using explosive gas mixtures, it is almost impossible to silence the first pressure wave and only use the second one, and using the first and second waves together makes it difficult to interpret seismograms.

Известны источники сейсмических сигналов дл акваторий, позвол ющие выделить первую волну давлени и ослабить вторую l , или использовать только вторую волну давлени 2 ,Sources of seismic signals for water areas are known, which allow to isolate the first pressure wave and weaken the second l, or use only the second pressure wave 2,

Известен источник сейсмических сигналов , содержащий корпус, выполненный из двух герметично соединенных пластин и упоров и средства создани разр жени в корнпусе . Устройство позвол ет получать одиночный сигнал. Основной его недостаток сложна конструкци .A source of seismic signals is known, comprising a housing made of two hermetically connected plates and stops, and means for creating a discharge in the core. The device can receive a single signal. Its main drawback is complex construction.

В качестве прототипа прин т источник сейсмических сигналов дл акваторий, содержащий корпус, вьгаолненный из двух пластин, герметично соединенных гибким элементом, и устройство, обеспечивающее перюмешение пластин tSJ . Этот источник сейсмосигналов также имеет сложную конструкцию - гидра&лический двигатель дл перемещени пластин , и кроме того, не позвол ет возбуждать одиночный сигналAs a prototype, a source of seismic signals for water areas is received, comprising a housing that is filled with two plates hermetically connected by a flexible element, and a device that permesh plates tSJ. This source of seismic signals also has a complex structure - a hydra & lytic engine for moving the plates, and in addition, it does not allow a single signal to be excited.

Целью изобретени вл етс выделение одиночной волны давлени . Поставленна цель достигаетс за счет того, что пластины снабжены ограничител ми расхождени , например тросами.The aim of the invention is to isolate a single pressure wave. This goal is achieved due to the fact that the plates are provided with divergence limiters, for example cables.

Claims

The drawing schematically shows the proposed source of seismic signals in the initial state. The source of seismic signals contains plates 1 and 2, fastened around the perimeter of the flexible element 3 by means of bolts 4, to which a shock absorber 5 is attached. The plates are also connected by a discrepancy limiter of plates 6, for example, a cable. The cavity enclosed between the plates and the flexible element 3 (the explosion chamber), through the controlled valve 7 and the pipeline 8, is connected to a source of a gas mixture (not shown). On plate 1, an electrical source for mixing mixture 9 is strengthened. A check valve choke 11 is connected to plate 2 through an outlet fitting 10. The source of seismic waves works as follows. The explosive gas mixture of hydrogen and oxygen enters through conduit 8 and the open controlled valve 7 into the explosion chamber. Under the pressure of the gas, plates 1 and 2 are diverted to the side for the distance limited by element 6. After this, the check valve-choke 11 closes and the internal cavity of the source from a certain amount of air located there is flushed with an explosive gas. At the beginning of the source operation, a purge is needed to maintain the stoichiometric C rate of gas. Subsequently, when, after a certain number of explosions, moisture (reaction product) accumulates in the cavity, which affects the identity of the seismic signal, purging the cavity with dry gas will dry the cavity. After purging the source is ready for operation. When an initiating impulse is ignited to a candle, an electric spark inside the cavity bounded by plates 1 and 2 causes the conversion of detonating gas into water vapor with a sharp formation of vacuum. Plates 1 and 2 under the action of evacuation and hydrostatic pressure of the environment converge, entraining the surrounding masses of water (at this moment the control valve 7 is closed). The speed of the plates is smoothly damped by shock absorbers 5. During a spontaneous pressure buildup inside the chamber, the throttle valve 11 does not have time to open due to the small cross section of the throttle bore. Due to the fact that plates 1 and 2 are held by divergence limiters 6 during a gas explosion (pressure 40-60 atm), the first pressure wave does not go through a seismic signal, and the second pressure wave (collapse of a vacuum chamber) produces a seismic signal . Limiters 6 make it possible to isolate a single pressure wave, which meets the pressing requirements of marine seismic surveys. The invention The source of seismic signals for water areas, comprising a housing made of two plates hermetically connected by a flexible element, and a device that provides movement of the plates, which is also due to the fact that, with the selection of a single pressure wave, equipped with restraints, such as cables. Sources of information taken into account in the examination: 1.Certificate of certificate № 224100, cl. Q 01 V, publ. 07.07.64

2. The patent of France No. 1583737, cl. G 01 V, issued 27.10.69.

3. US patent number 3482646, 181-5, issued 12/09/1969 (prototype).