Chuandong Jiang

Jilin University | JUT · College of Instrumentation Science and Electrical Engineering

Surface nuclear magnetic resonance (surface-NMR) is a promising technique for exploring shallow subsurface aquifer structures. Surface-NMR can be applied in environments that are characterized as a 1-D layered Earth. The technique utilizes a single loop and is referred to as magnetic resonance sounding. The technique referred to as magnetic resonan...

Surface nuclear magnetic resonance is a valuable technique that provides insight into the distribution of water content and relaxation time, thus revealing hydraulic properties in the subsurface. Recent research has introduced a new measurement layout that allows for time-efficient imaging of the 2D parameter distribution. Furthermore, for 1D inves...

Geophysical methods can characterize aquifer systems non-invasively and are particularly helpful to image the complex depositional structure of the subsurface.Among these, ground-penetrating radar (GPR) is an effective tool for detailed investigations of shallow subsurface geometry, but provides only limited information on hydraulic properties.Magn...

Surface nuclear magnetic resonance (sNMR) can directly and quantitatively detect groundwater, but its application in urban environments faces problems, such as low signal-to-noise ratios (SNRs) and difficulties in laying the coils. This study presents a rotational sNMR measurement scheme to accurately image a frozen urban lake. Through synthetic da...

Magnetic resonance tomography (MRT) has the advantages of direct, quantitative and unique interpretation in the field of groundwater detection. Currently, the inversion of MRT data primarily uses the QT (Q-time) inversion method based on Tikhonov regularization. However, when the heterogeneity of an aquifer is high, and the water content distributi...

The Cedaya-S340 Holgutu Highway Construction Project is located in the Mongolian Autonomous Prefecture of Bayingolin in the Xinjiang Uygur Autonomous Region. It is an important traffic channel that connects Luntai County and Hejing County at the southern foot of Tianshan Mountains. As the major component of the highway project, the Huola Mountain T...

Magnetic resonance sounding (MRS) is one of the technical applications of nuclear magnetic resonance (NMR) used to directly detect and quantify groundwater content. MRS suffers from a low signal-to-noise ratio (SNR) due to the low amplitude of free induction decay (FID) signals and an inability to shield environmental noise. In this paper, a time-f...

When using magnetic resonance tomography (MRT) for imaging two- or three-dimensional (2D or 3D) water-bearing structures in a subsurface, the transmitting frequency must be the same as the Larmor frequency. Due to the inhomogeneity and noise interference in a geomagnetic field, it is difficult to determine the precise Larmor frequency using a magne...

Magnetic-resonance sounding (MRS) is a direct, quantitative, accurate and efficient technology that has been applied in the fields of groundwater detection, regional water-resource investigation and geological-disaster-risk early warning. However, owing to strong environmental noise, the signal-to-noise ratio (SNR) of data collected by MRS instrume...

The Hunshandake Sandy Land (HSL) is a well-known water-rich sandy region in China that is home to many lakes. Most of these lakes are sustained by groundwater inflow. However, due to the limited hydrogeological survey data, the mechanism by which the lakes interact with groundwater is not well understood. Magnetic resonance sounding (MRS) is a geop...

In tunnel construction, to prevent the occurrence of water inrush, the geological conditions of faults and underground rivers must be determined in advance. As a direct detection method of groundwater, magnetic resonance sounding (MRS) has been applied for the advanced detection of water-related hazards in tunnels and mines recently. However, the r...

Magnetic resonance sounding (MRS) has been applied to underground constructions, such as tunnels and mines, to detect and forewarn groundwater sources hidden in front of the mine face, also named disaster water sources. Disaster water sources are mostly found in 2-D or 3-D structures; as such, their spatial distribution characteristics are difficul...

Based on surface magnetic resonance sounding (MRS), a relationship is proposed to express the MRS response signal with a vertical coil for the MRS method for a whole underground space model. Firstly, the declination and inclination characteristics of the Earth's magnetic field and the coil normal angle are studied by deriving the angle rotation mat...

In surface nuclear magnetic resonance, we use the geomagnetic field as the background field and excite hydrogen protons in groundwater by emitting an alternating current with a frequency equal to the Larmor frequency. However, in practical, inhomogeneous geomagnetic field (IGF) or magnetic anomaly caused by ferromagnetic materials will make the non...

Surface and underground nuclear magnetic resonance (UNMR) method has the advantage of direct and quantitative detection of groundwater and has been widely used in water resource survey and advance detection of water sources causing disaster in underground space. However, the UNMR signal is extremely weak in tunnels or mines. The signal-to-noise rat...

Magnetic resonance sounding (MRS) is a geophysical method that directly detects, evaluates, and monitors groundwater resource. The amplitude of the MRS signal detected by the instrument is on the order of nanovolts, resulting in very sensitive to environmental noise and power line harmonics. The singular value decomposition (SVD) method separates t...

Surface nuclear magnetic resonance (surface NMR) is a geophysical technique for direct and quantitative detection of underground water sources. In recent years, with the application of lightweight instruments in tunnels and mines, coils with small dimensions and multi-turn have been used for surface NMR. Increasing the coil turns increases the indu...

Field data of MRS collected by JLMRS-Array instrument in Taipingchi Reservoir, Changchun City of China.

Field data after DSVD process

The Ground-source Airborne Time-domain Electromagnetic (GATEM) method is an efficient electromagnetic prospecting technique for engineering, geological surveying and mineral exploration. The electromagnetic response and inversion are obtained via the electrical conductivity of the geological medium, which is conventionally characterized by a homoge...

The magnetic resonance sounding (MRS) method can noninvasively, directly, and quantitatively detect groundwater and forecast the potential for a water-induced disaster during tunnel construction. However, due to the spatial limitations of underground engineering, the signal-to-noise ratio (SNR) of the receiving signal is low (<1), which severely li...

Magnetic resonance tomography (MRT) is a technique that is used in the 2-D or 3-D detection and imaging of subsurface water-bearing structures based on the principle of surface nuclear magnetic resonance. Currently, the research and application of 3-D MRT is still limited by low measurement efficiency and image resolution. In this paper, a new loop...

The Dadushan Tunnel, which is located in the southwestern karst region of China in Guizhou Province, is one of the key elements of the Hukun High-Speed Railway. Cavities occur unpredictably in the tunnel, and well-developed karst conduits are frequently encountered. These features result in safety problems, such as water gushing and rapid flooding....

Surface nuclear magnetic resonance (SNMR) data typically suffer from very low signal-tonoise ratio. Two of the main sources of noise that generate low signal-to-noise ratios are powerlines and railways that create harmonic noise. Some noise cancellation strategies for mitigating this harmonic noise have been presented. However, when the frequency o...

Underground construction projects such as tunnel construction are at high risk of water-induced disasters. Because this type of disaster poses a serious threat to worker safety and productivity, instruments and methods that can accurately detect the water source are critical. In this study, a water detection instrument that combines Magnetic Resona...

As the surface nuclear magnetic resonance signal (SNMR) is a multi-exponential decay wave in multi-porous aquifer, there are serious problems of signal distortion and information loss by conventional blind source signal extraction and mono-exponential fitting method. In this paper, we propose a method to extract multi-exponential SNMR signals from...

Advanced detection of underground hazardous water in mines or tunnels is a new application field of the magnetic resonance sounding (MRS) method, as well as a new challenge in geophysics. In this paper, on the theoretical basis of the surface MRS method, a model of underground MRS of whole space is constructed, and the expression of MRS signal with...

A new method for detecting risk of tunnel water-induced disasters using magnetic resonance sounding (MRS) is proposed in this letter. The method utilizes magnetic resonance signals that are generated directly from hydrogen protons to achieve the purpose of detecting risk of tunnel water-induced disasters directly and quantitatively. This letter eva...

Magnetic resonance sounding (MRS) is a novel geophysical method to detect groundwater directly. By applying this method to underground projects in mines and tunnels, warning information can be provided on water bodies that are hidden in front prior to excavation and thus reduce the risk of casualties and accidents. However, unlike its application t...

During the excavation of underground tunnels and ore mining, accidents related to sudden water inflows often occur. As the only technique used for the direct detection of groundwater, nuclear magnetic resonance (NMR) has advantages for the detection of disaster-inducing water flows. However, NMR has commonly been applied only at the ground surface...

Magnetic Resonance Sounding (MRS) is a non-invasive geophysical technique providing the ability to quantitatively and directly detect the aquifer properties, which is commonly used in groundwater survey, hydrological assessment and advanced detection of a water source that may cause disastrous accident in the underground engineering. In field appli...

As a new groundwater exploration method, noninvasive surface nuclear magnetic resonance (SNMR) has the benefits of direct, quantitative and uniqueness estimation of water content and relaxation time (T2*) in the near surface groundwater exploration. In practice, the earth magnetic field is difficult to be determined accurately, due to its inhomogen...

Due to its unique sensitivity to hydrogen protons, magnetic resonance sounding (MRS) is the only geophysical method that directly detects water and can provide nondestructive information on subsurface aquifer properties. The relationship between the surface MRS signal and the location and characteristics of aquifers using large-coil (typically 50–1...

Magnetic resonance tomography using elongated transmitter and in-loop receiver arrays (MRTetra) is designed to efficiently image the groundwater in two-dimensional. However, due to resolution limitations and the volume effect, the structure and boundary features of the aquifer are ambiguous. We make use of the GPR reflection data to generate struct...

Magnetic resonance sounding (MRS) using the Earth’s magnetic field is a noninvasive and on-site geophysical technique providing quantitative characteristics of aquifers in the subsurface. When the MRS technology is applied in a mine or tunnel for advance detecting the source of water that may cause disastrous accident, spatial constraints limit the...

Nano-volt magnetic resonance sounding (MRS) signals are sufficiently weak so that during the actual measurement, they are affected by environmental electromagnetic noise, leading to inaccuracy of the extracted characteristic parameters and hindering effective inverse interpretation. Considering the complexity and non-homogeneous spatial distributio...

The water content of underground structures can be imaged using surface nuclear magnetic resonance (NMR) in one dimension, two dimensions, or recently, three dimensions. The maximum efficiency can be obtained with a coincident loop configuration in a large-scale area, although the resolution is limited. We have developed a quasi-2D block inversion...

The technology of low-field nuclear magnetic resonance (LF-NMR) is commonly used in food, agriculture, energy and chemical sectors due to its non-destructive, non-invasive, in situ, green and other advantages. Recently, this technology played an increasingly large role in the field of food-safety supervision especially. In oil product quality testi...

An optimized Block inversion method is proposed in order to satisfy the high accuracy requirement of the aquifer boundary with Magnetic Resonance Sounding (MRS). The priori information is established from the derivative result of the Smooth inversion, which provides the smooth distribution of the water content. Based on the Tikhonov regularized inv...

Surface nuclear magnetic resonance (surface NMR) has up to now rarely been applied to 3D subsurface modeling. Inversion approaches currently in use are smooth inversion techniques that are not useful for identifying sharp geologic boundaries. Although they are already computationally expensive, the resulting models are restricted to imaging the sub...

Magnetic Resonance Sounding (MRS) signal is extremely easy corrupted by the noise, especially by the harmonic noise and spike noise. Harmonic noise cancellation is often based on remote references and the adaptive noise cancellation(ANC)algorithm to increase the signal-to-noise ratio (SNR). However, ANC algorithm cannot play an effective role when...

Least Square Weighted Smoothing Filter (LSW-SF) method is used to filter Magnetic Resonance Sound (MRS) signals, which is compared with the moving average filter method. Results of a large number of simulation experiments show the following characteristics. First, the more accurate characteristic parameters of MRS can be obtained using the LSW-SF m...

To meet the accuracy requirement of surface three-dimensional (3D) Magnetic Resonance Spectroscopy (MRS) forward modeling. Hammer integration algorithm was proposed based on unstructured non-uniform tetrahedral mesh. First, finite element method was used to calculate the 3D magnetic field in the subsurface, and the sensitivity kernel expression was...

The technique of surface NMR has been applied to image 1D, 2D and recently 3D subsurface structures. Although limited resolution is reported for imaging deep 3D structures using a coincident loop configuration, high resolution is obtained for shallow 2D structures by including separated loop configurations. We adapt the concept of separated transmi...

Surface nuclear magnetic resonance is a geophysical method designed for direct groundwater exploration, but its applications for conducting research on contamination analysis in the vadose zone are limited due to instrumental dead time. To address this challenge, we have modeled and simulated the phenomenon and impact of the transmitter loop discha...

Magnetic Resonance Sounding (MRS) has received much attention of geophysicists due to its qualitative and quantitative features in detection of groundwater. In traditional studies, people are limited to one-dimensional of instruments and interpretation methods based on layering aquifer models, which makes well location difficult in complex geologic...

Surface Magnetic Resonance Sounding (SMRS) has emerged as a new geophysical technique which allows detecting the abundant degree of hydrogen nucleus in the subsurface directly on the surface. It has been widely used, not only in groundwater exploration and evaluation, but also in water-induced disasters (disasters caused by groundwater, such as dam...

The method of Magnetic Resonance Sounding (MRS) provides a new technology to determine subsurface water qualitatively and quantitatively, which has received much concern of geophysicists. The traditional inversion of MRS uses homogeneous half-space models and ignores effects of resistivity distribution on inversion results. Based on the MRS theory...

The amplitude and relaxation time T2 of magnetic resonance sounding (MRS) signal are directly related with water content and pore size of aquifers. Average T2, denoted by T2*, is often used to describe the decay characteristic of MRS signal. However, in the case of porous media rock, pore size should be described by T2 spectrum of MRS signal. To ob...

Smooth inversion and block inversion are two main methods for surface magnetic resonance sounding (MRS) at present, which can construct water content and average effective pore size of aquifer through initial amplitudes and mean relaxation times, respectively. However, these inversion methods are limited in porous geological environment and in some...

The traditional interpretation scheme of Magnetic Resonance Sounding (MRS) used to limit to the homogeneous half-space and regardless of the resistivity in the inversion, in turn resulting in the ambiguous aquifer boundaries. Based on the MRS theory in the multi-layer earth model, we developed a new scheme for joint inversion of MRS data and Transi...

The receiving signal of Magnetic Resonance Sounding (MRS) is mainly influenced by the transfer characteristic of detection coil, which can be significantly affected as the transfer characteristic plays an important role. After review of the recent studies around the world, the assessment method of transfer characteristic for receiver coil is propos...

We present a new loop configuration provides high subsurface resolution for Magnetic Resonance Tomography (MRT) by only one measurement. Model resolution matrix and radius are analyzed based on singular value de composition (SVD) of the MRT kernels including regularization. We take two shapes of the transmitter loop, square and rectangle, and two c...

Nuclear magnetic resonance (NMR) has emerged as a new geophysical technique allowing direct, noninvasive groundwater investigations from the surface.. Comparing to the traditional geophysical methods, the current state-of-the-art NMR method is higher resolution, more efficiency, more information and unique interpretation for hydrogeological investi...

To detect the hidden leakage problem of a dam body accurately, a new geophysical method, magnetic resonance sounding (MRS), is introduced, which can directly detect water molecules and quantitatively measure them. The basic principle and inversion method of MRS is research to determine the coil type and measurement mode for dam leakage problem. Fie...

Magnetic Resonance Sounding (MRS) is a geophysical method designed for direct groundwater exploration. Initially, MRS was developed for characterizing horizontally stratified aquifers. However, for the 2D/3D target whose size may be much smaller than the loop, the accuracy and the lateral resolution may not be sufficient. In this paper, possibility...

Traditionally, one of the major limitations for magnetic resonance sounding (MRS) measurement is that the weak signal generated by subsurface water molecules is prone to be disturbed by highlevel electromagnetic noise. In China, the power grid coverage is 94.6% and spiky noise and power-line harmonic noise are always present when utilizing MRS meas...

Magnetic Resonance Sounding (MRS) equipment for groundwater exploration has high receiving sensitivity, and it is vulnerably affected by high-level power-line harmonic when worked near the city and village. In order to effectively extract the weak signal, variable step-size LMS algorithm in frequency domain is studied to eliminate noise based on th...

The existing Magnetic Resonance Sounding (MRS) system for groundwater exploration can detect the deep groundwater, transmit a high power, and hold a large size and weight. Due to the conditions of transportation and instrument preparation time, the work efficiency of the existing system has not obvious advantage to detect the widespread shallow gro...

The magnetic resonance sounding(MRS) method is a non-invasive and most direct geophysical method for the groundwater. The envelop free induction decay(FID) signal of MRS includes the key parameters for detecting underground water. Based on the switch orthogonal vector lock-in amplifier principle and the trigonometric function specificity, the FID s...

A new method for 2D groundwater tomography using Magnetic Resonance Sounding (MRS) with distributed array loops is described and the exciting field of the surface transmitter and the response from the spin magnetic field to the receivers are numerical calculated. To assess the effective effort in subsurface structure resolution by the use of 2D MRS...

MRS (magnetic resonance sounding)) method is a direct method for underground water detecting which is easily disturbed by interferences according to its weak signal (nV). Time domain quantization methods require a good suppression of interferences for more accurate MRS signal parameter estimation. Of all interferences, power line harmonic interfere...