摘要:
Devices for sensing gradients are constructed from material whose properties change in response to gradients. One embodiment of the device is a transducer (200) for sensing gradients that includes the material (210) and two or more electrodes (240, 270) coupled to the material. In one embodiment, gradients in a surrounding medium (110) modify the energy gap of the material in the transducer (130) producing a diffusion current density (150). The material is configured to connect to a current or voltage measurement device (520, 530, 540) where a measurement is used to determine the gradient in the medium (160). The devices can be used to measure pressure, temperature, and/or other properties. The transducer can be built on the same substrate as complementary circuitry. A transducer made of Indium. Antimonide is used in marine seismology to measure pressure gradients.
摘要:
The invention concerns a method to acquire seismic waves by means of a streamer towed by a vessel and comprising a plurality of seismic receivers. The streamer comprises a head portion that is slanted relative to the water surface and a tail portion having at least one section with a different slant.
摘要:
A measured pressure field, a measured vertical velocity field, and two measured orthogonal horizontal velocity fields are obtained. A programmable computer is used to perform the following. A scaling factor is determined from water acoustic impedance, the measured pressure field, and the horizontal velocity fields. One of the measured pressure field and measured vertical velocity field is combined with one of the measured vertical velocity field scaled by the scaling factor and the measured pressure field scaled by the scaling factor, generating one of up-going and down-going pressure and velocity wavefields.
摘要:
A vibration sensing device, package and system and a method of manufacturing a vibration sensing device are disclosed. The vibration sensing device comprises a body whose geometry is such that it exhibits flextensional properties.
摘要:
In one embodiment the invention comprises a particle velocity sensor that includes a housing with a geophone mounted in the housing. A fluid that substantially surrounds the geophone is included within the housing. The particle velocity sensor has an acoustic impedance within the range of about 750,000 Newton seconds per cubic meter (Ns/m3) to about 3,000,000 Newton seconds per cubic meter (Ns/m3). In another embodiment the invention comprises method of geophysical exploration in which a seismic signal is generated in a body of water and detected with a plurality of co-located particle velocity sensors and pressure gradient sensors positioned within a seismic cable. The output signal of either or both of the particle velocity sensors or the pressure gradient sensors is modified to substantially equalize the output signals from the particle velocity sensors and the pressure gradient sensors. The output signals from particle velocity sensors and pressure gradient sensors are then combined.
摘要翻译:在一个实施例中,本发明包括粒子速度传感器,其包括具有安装在壳体中的地震检波器的壳体。 基本上围绕地震检波器的流体包括在壳体内。 粒子速度传感器的声阻抗在每立方米约750,000牛顿秒(Ns / m 3)至约3,000,000牛顿秒/立方米(Ns / m 3)之间。 在另一个实施例中,本发明包括地球物理勘探方法,其中在水体中产生地震信号并且利用位于地震缆索内的多个共同定位的粒子速度传感器和压力梯度传感器进行检测。 粒子速度传感器或压力梯度传感器中的任一个或两者的输出信号被修改为基本上均衡来自粒子速度传感器和压力梯度传感器的输出信号。 然后组合来自粒子速度传感器和压力梯度传感器的输出信号。
摘要:
A self-orienting seismic detector for detecting vertical acceleration regardless of the device's horizontal orientation. The detector comprises a housing fitted with diaphragms capable of generating signals. A mass is internally suspended within the housing between the diaphragms by means of a filament which is connected at each of its ends to one of the diaphragms. Vertical motion of the detector causes internal displacement of the mass within the housing. Motion by the mass within the cylinder is translated by the filament to the diaphragms which generate signals which may then be recorded. The detector may be incorporated within or attached to an undersea cable to form a seismic detection system primarily suitable for placement on an ocean bottom, but which may be employed in a towed array. In a primary embodiment, the detector is sealed from external pressure changes such that the stresses placed upon the detector's diaphragms will be governed by particle acceleration changes rather than pressure changes. In an alternative embodiment, the detector is exposed to external pressure. In this embodiment, the detector acts as a dual sensor-type system, incorporating the data gathering features of both a geophone and a hydrophone.
摘要:
A method and apparatus for measuring and identifying up- and down-traveling waves wherein both a velocity-sensitive and pressure-sensitive transducer are disposed at a point below the earth's surface, as for example in a borehole that is refilled. The pressure transducer is designed to provide intimate contact with the formation surrounding the borehole, and in addition, is the electrical equivalent of the velocity transducer.
摘要:
A method of manufacturing a streamer section. The method includes coupling together a plurality of prefabricated harness modules. A harness module includes a plurality of geophysical sensors disposed along a length of the harness module and a sensor node communicatively coupled to the plurality of sensors. A first connector is disposed at a first end of the harness module and a second connector disposed at a second end of the harness module. The first connector is coupled to the sensor node and is configured to couple to a second harness module and receive data from a sensor node in the second harness module. The second connector is coupled to the sensor node and is configured to couple to a third harness module and forward data to a sensor node in the third harness module.
摘要:
A sensor system for use in a wellbore is provided that can include a piezoelectric transducer for transmitting an acoustic wave into a fluid medium positioned in the wellbore by repeatedly bending between two positions in response to an actuation signal. The piezoelectric transducer can include at least four piezoelectric layers stacked on top of one another. Each of the four piezoelectric layers can be coupled to an adjacent layer via a bonding material. Each of the four piezoelectric layers can include a piezoelectric material, a top electrode coupled to a top surface of the piezoelectric material, and a bottom electrode coupled to a bottom surface of the piezoelectric material. The sensor system can also include a hydrophone for detecting a reflection or a refraction of the acoustic wave off an object in the wellbore and transmitting an associated signal to a processing device.
摘要:
A system and method for acquiring seismic streamer data is provided. Embodiments may include performing a marine seismic survey using an unmanned marine vessel having a power source configured to drive and provide propulsion to the unmanned marine vessel. Embodiments may further include acquiring one or more of long and ultra-long seismic survey data using a multi-dimensional seismic sensor array coupled with the unmanned marine vessel and providing the seismic survey data as a reduced data set that includes long and ultra long offsets.