With the advancement of deep Earth exploration and urban underground space detection, addressing the challenges posed by environmental complexity and increasing data acquisition accuracy are increasingly critical. Conventional geophysical exploration techniques and their associated networking approaches cannot fulfill contemporary exploration requirements. Herein, the fundamental principles and inherent connections between seismic exploration and electromagnetic exploration are analyzed by comparing the circuit design for seismic and electromagnetic data-acquisition systems. Consequently, a technical solution for a seismo-electromagnetic joint acquisition system with high accuracies in both seismic and electromagnetic explorations is developed. A real-time host monitoring system is developed for both personal computers and mobile terminals. Moreover, a distributed hybrid networking scheme for this distributed seismo-electromagnetic high-accuracy acquisition system that incorporates wired, wireless, and self-storage intelligent arbitrary clipping is innovatively implemented, achieving a synchronization accuracy of <100 ns among various acquisition systems. The developed system is used for networking deployment in Zhangjiakou (Hebei, China), verification of key indicators in a coal mine with a depth of 848 m in Huainan (Anhui, China), and practical onsite explorations in Changzhi (Shanxi, China). The experimental and application results verify the reliability, stability, and practicality of the system. The proposed joint exploration technique fully leverages the advantages of distributed data-acquisition systems and can potentially shed light on the development of other joint research methodologies. The findings can increase the efficiency and accuracy of joint geophysical explorations, providing a solid foundation with regard to both machinery and technical aspects.

The high-precision magnetic survey system is crucial for ocean exploration. However, most existing systems face challenges such as high noise levels, low sensitivity, and inadequate magnetic compensation effects. To address these issues, we developed a high-precision magnetic survey system based on the manned submersible “Deep Sea Warrior” for deep-ocean magnetic exploration. This system incorporates a compact optically pumped cesium (Cs) magnetometer sensor to measure the total strength of the external magnetic field. Additionally, a magnetic compensation sensor is included at the front end to measure real-time attitude changes of the platform. The measured data are then transmitted to a magnetic signal processor, where an algorithm compensates for the platform’s magnetic interference. We also designed a deep pressure chamber to allow for a maximum working depth of 4500 m. Experiments conducted in both indoor and field environments verified the performance of the proposed magnetic survey system. The results showed that the system’s sensitivity is ≤0.5 nT, the noise level of the magnetometer sensor is ≤1 pT/√Hz at 1 Hz, and the sampling rate is 10 Hz. The proposed system has potential applications in ocean and geophysical exploration.

High-precision magnetometers play a crucial role in ocean exploration, geophysical prospecting, and military and security applications. Installing them on human-occupied vehicle (HOV) platforms can greatly enhance ocean exploration capabilities and efficiency. However, most existing magnetometers suffer from low sensitivity and excessively large size. This study presents a high-sensitivity, miniaturized magnetometer based on cesium optically pumped probes. The designed magnetometer utilizes a three-probe design to eliminate the detection dead zone of the cesium optically pumped probe and enable three-dimensional magnetic detection. The proposed magnetometer uses a flux gate probe to detect the three-axis magnetic field and ensure that the probe does not enter the dead zone. The three probes can automatically switch by measuring the geomagnetic elements and real-time attitude of the HOV platform. This article primarily introduces the cesium three-probe optically pump, flux gate sensor, and automatic switching scheme design of the above-mentioned magnetometer. Moreover, it is proven through testing that the core indicators, such as the accuracy and sensitivity of the cesium three-probe optically pumped and flux gate sensor, reach international standards. Finally, the effectiveness of the automatic switching scheme proposed in this study is demonstrated through drone-mounted experiments.

Human-Occupied Vehicles (HOVs) provide an ideal platform for high-resolution near-bottom magnetic anomaly detection. Nevertheless, complex self-generated magnetic interference from the vehicle platform severely limits the extraction accuracy of weak magnetic signals. While the classic Tolles–Lawson (T–L) model relies upon large-amplitude attitude maneuvers to calculate interference coefficients, such specific actions are unfeasible for HOVs due to their large inertia, hydrodynamic coupling, and deep-sea safety constraints. To address this, we propose a ”kinematic-excitation magnetic compensation” method leveraging the platform's inherent dynamic characteristics. By commanding the HOV to perform speed acceleration–deceleration cycles and horizontal S-shaped turns, the method indirectly excites pitch and roll attitude variations through fluid–structure coupling, effectively constructing the complete feature space required for the T–L model. Field results using the 'Deep-Sea Warrior' HOV demonstrate that this method reduces the noise standard deviation from 0.8870 nT to 0.4157 nT, achieving an improvement ratio of 2.13. This work verifies the method’s robustness under constrained-maneuver conditions and provides a practical engineering solution for achieving reliable sub-nanotesla high-precision deep-sea magnetic surveying on manned submersible platforms.