According to at least one aspect, a river velocity estimation system is provided. The river velocity estimation system includes one or more components executable by at least one processor that are configured to receive terrain information and at least one image including a river, identify an area of interest in the at least one image that includes the river, identify a course of the river and a boundary of the river based on the area of interest in the at least one image, estimate a slope of the river based on the terrain information, determine a hydraulic radius of the river based on the boundary of the river and the course of the river, and estimate a flow rate of water in the river based on at least the slope of the river and the hydraulic radius of the river.

The present invention discloses a new submerged buoy data acquisition system, including a battery compartment, a main control processor, a GPS receiver, a gigabit Ethernet interface module, and a plurality of data acquisition boards, where the GPS receiver is connected to the main control processor, and the main control processor is connected to a host computer by using the gigabit Ethernet interface module; the data acquisition board includes a hydrophone sensor, a front-end drive circuit, an AD conversion circuit, a clock module, a DA conversion circuit, an FPGA, an ARM processor, and a storage module; the hydrophone sensor is connected to the AD conversion circuit by using the front-end drive circuit, the AD conversion circuit is connected to the FPGA, the FPGA is connected to the ARM processor, the storage module is connected to the ARM processor, the DA conversion circuit is connected to the FPGA and the clock module, the clock module is connected to the FPGA, and the ARM processor is connected to the main control processor. The present invention improves acquisition performance of the submerged buoy data acquisition system, and implements synchronous acquisition and control of the entire system.

This disclosure describes systems and methods to predict viscosity of heavy oil in a geological formation, even when the geological formation also contains water such as clay-bound water, using a downhole nuclear magnetic resonance (NMR) tool. The downhole NMR tools may obtain responses include distributions of a first relaxation time T1, a second relaxation time T2, or diffusion, or a combination of these. The responses of the NMR measurements that are due to water are separated from the responses of the NMR measurements that are due to heavy oil. The responses of the NMR measurements due to heavy oil are then related to likely values of viscosity of the heavy oil based on empirical or simulated measurements.

The present disclosure provides a cuboid magnetometer with high fluorescence collection efficiency, used for cardiac magnetic field measurement, and based on nitrogen-vacancy (NV) centers in diamond, and a cardiac magnetic field measurement system. The cardiac magnetic field measurement system includes a magnetic shielding chamber, a non-magnetic bed, an array probe for cardiac magnetic field measurement, a three-axis displacement platform, a high-speed data collection card, a fiber laser source, a microwave source, and a computer. The array probe for cardiac magnetic field measurement includes a non-magnetic shell, a stepping motor, a porous rotary fiber coupling apparatus, a fiber bundle set, a special photodetector (PD) set, a filter set, a ring-shaped antenna, and special diamond.

The present disclosure relates to a method for advancedly detecting a water-bearing hazard body in real-time based on vector resistivities. The method includes: acquiring potential differences of receiving dipoles on a shield machine in real-time based on a pre-constructed detection environment, wherein the receiving dipoles include first receiving dipoles and a second receiving dipole; converting to resistivities by using a formula for calculating resistivities in a steady current field according to relative positional relationships between the receiving dipoles and power supply dipoles and the potential differences of the receiving dipoles to obtain the apparent resistivities of the receiving dipoles; drawing curves of the apparent resistivities of the receiving dipoles by taking positions of the power supply dipoles as an abscissa axis and the apparent resistivities as an ordinate axis; analyzing the changing curves of the apparent resistivities and determining a detection result of an abnormal body. According to this method, in the process of a continuous underground tunneling of the shield machine, the conditions of the water-bearing hazard body in front of the tunneling is detected in real-time by means of continuously receiving electric signals by the receiving dipoles and drawing the curves of the apparent resistivities of the receiving dipoles, thereby improving the real-time performance of the advanced prediction results.

A method and source element for generating seismic waves in water. The source element includes a housing having an opening; an acoustic piston closing the opening; an actuating mechanism located inside the housing and configured to actuate the acoustic piston; and a decoupling mechanism interposed between the acoustic piston and the actuating mechanism. The decoupling mechanism allows the acoustic piston to move substantially independent of the actuating mechanism for a first frequency range.

Downhole fluid volumes of a geological formation may be estimated using nuclear magnetic resonance (NMR) measurements, even in organic shale reservoirs. Multi-dimensional NMR measurements, such as two-dimensional NMR measurements and/or, in some cases, one or more well-logging measurements relating to total organic carbon may be used to estimate downhole fluid volumes of hydrocarbons such as bitumen, light hydrocarbon, kerogen, and/or water. Having identified the fluid volumes in this manner or any other suitable manner from the NMR measurements, a reservoir producibility index (RPI) may be generated. The downhole fluid volumes and/or the RPI may be output on a well log to enable an operator to make operational and strategic decisions for well production.

An anti-saturation device for a ground magnetic resonance signal amplifying circuit has a receiving coil connected with a band-pass filter circuit through a pre-amplifying circuit and a programmable amplifying circuit. The programmable amplifying circuit is connected with an AD acquisition card through the band-pass filter circuit. The band-pass filtering circuit is connected with a computer through the AD acquisition card, and the AD acquisition card is connected with an emitting system through the computer. An automatic amplification factor adjusting module is embedded into a nuclear magnetic resonance detector, and can also directly replace a receiving amplification circuit of the nuclear magnetic resonance detector to work independently.

Provided in some embodiments are systems and methods for determining characteristics of a hydrocarbon reservoir. Embodiments include conducting a nuclear magnetic resonance (NMR) logging operation of a targeted reservoir section of a wellbore extending into a hydrocarbon reservoir to generate a NMR log of the targeted reservoir section, conducting a resistivity logging of the targeted reservoir section to generate an uninvaded water saturation (S.sub.w) log of the targeted reservoir section, determining for each of a plurality of depths in the section, a T.sub.2 cutoff point based on values of the NMR and S.sub.w logs, identifying a subset of the T.sub.2 cutoff points that exhibit a hyperbolic trend, determining a theoretical cutoff curve corresponding to the subset of the T.sub.2 cutoff points, determining a free water level (FWL) of the reservoir based on the theoretical cutoff curve, and determining a rock type of the reservoir based on the theoretical cutoff curve.

A method for measuring oil-water distribution using DNP-MRI, comprising adding a free radical for DNP enhanced NMR signal of a water phase or an oil phase in a sample containing oil and water; performing an MRI experiment on the sample, and collecting an MRI image of the sample without DNP enhancement; applying microwave excitation for DNP-MRI experiment under the same MRI experiment condition as step 2, and collecting an MRI image of the sample after DNP enhancement; and comparing the MRI image after DNP enhancement with the MRI image without DNP enhancement. In the MRI image with DNP enhancement, an area with enhanced MRI signal intensity is a selectively enhanced fluid phase distribution area, and an area without obviously changed MRI signal intensity is a non-selectively enhanced fluid phase distribution area. The method is simple, convenient to operate, short in measurement time, and high in measurement efficiency.