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Natural gas hydrate (GH) is a significant potential energy source. However, the gas production rate of past GH production tests is much lower than the requirement of commercial gas production. Reservoir stimulation technologies like hydraulic fracture provide one potential approach to enhance gas production from GH. This paper presents an experimental facility that was developed to analyze the hydraulic fracture mechanism in a synthesized hydrate-bearing sediments.

We have developed a novel flexible measurement array for deep landslide displacement and measurement processes, which enables higher accuracy in full-hole multidimensional deformation measurement. It provides a more comprehensive monitoring tool for disaster prevention and reduction.

Geomagnetic observatories are dedicated to the long-term monitoring of the Earth's magnetic field. Their time series contain information mainly about the Earth's core and the near-Earth space environment. MOSFiT accesses a global database with the most recent observatory data and allows us to separate the information about the Earth's core. At the same time, it allows for an efficient check of the data quality. We present the code, validate it and explain its usage.

Much of the world relies on groundwater as a water resource, yet it is hard to know when and where rainfall replenishes our groundwater aquifers. Caves, mines, and tunnels that are situated above the groundwater table are unique observatories of water transiting from the land surface to the aquifer. This paper will show how networks of loggers deployed in these underground spaces across Australia have helped understand when, where, and how much rainfall is needed to replenish the groundwater.

Soil moisture monitoring is important for many applications, from improving weather prediction to supporting agriculture practices. Our capability to measure this variable is still, however, limited. In this study, we show the tests conducted on a new soil moisture sensor at several locations. The results show that the new sensor is a valid and compact alternative to more conventional, non-invasive soil moisture sensors that can pave the way for a wide range of applications.

We present the implementation of a VLF/LF network to search for earthquake electromagnetic precursors. The proposed system will deliver a steady stream of real-time amplitude and phase measurements as well as a daily recording VLF/LF data set. The first implementation of the system was done in Graz, Austria. The second one will be in Guyancourt (France), with a third one in Réunion (France) and a fourth one in Moratuwa (Sri Lanka).

AERO and VISTA spacecraft will use commercial magnetometers to measure space weather events near Earth’s aurora. The small size of AERO and VISTA necessitate the use of magnetometers with small size, weight, and power. The magnetometers selected exhibit good precision, but additional calibration is needed to achieve good accuracy. This work evaluates a method for calibration by regression which has reduced the magnetic observed error by a factor of ca. 50, meeting mission requirements.

Spaceflight magnetic-field measurements are often contaminated by interference from the host spacecraft. We present a new dataset to enable the development and testing of interference mitigation schemes for spaceflight magnetic-field data. Over 100 h of data, including laboratory-generated proxies for magnetic interference and geophysical signals, have been produced. A ground truth for the underlying interference is also provided, enabling the rigorous quantification of data-cleaning techniques.

Demonstrating the space flight capability of the next generation of precise, reliable magnetic field instruments is important for enabling future space science missions that will further our understanding of the connection between Earth's magnetic field and the Sun. Here, we present a new magnetic field instrument design called Tesseract, the results from its successful first space flight demonstration aboard a rocket, and its measurements of magnetic fields associated with the aurora.

The remote-sensing InSAR technique is vital for monitoring slope instabilities but requires understanding. This paper delves into differences between satellite and GB-InSAR. It offers a tool to determine the optimal GB-InSAR installation site, considering various technical, meteorological, and topographical factors. By generating detailed maps and simulating radar image characteristics, the tool eases the setup of monitoring campaigns for effective and accurate ground movement tracking.

We compared wind measurements using different lidar setups at various heights. The triple Doppler lidar, sonic anemometer, and two single Doppler lidars were tested. Overall, the lidar methods showed good agreement with the sonic anemometer. The triple Doppler lidar performed better than single Doppler lidars, especially at higher altitudes. We also developed a new filtering approach for virtual tower scanning strategies. Single Doppler lidars provide reliable wind data over flat terrain.

Low-cost sensors could fill gaps in existing observation networks. To ensure data quality, the quality of the factory calibration of a given sensor has to be evaluated if the sensor is used out of the box. Here, the factory calibration of a widely used low-cost rain gauge type has been tested both in the lab (66) and in the field (20). The results of the study suggest that the calibration of this particular type should at least be checked for every sensor before being used.

We present the experimental results of a new copper-based alloy suitable for use in high-precision magnetic sensing. It outperforms by providing lower magnetic noise and superior power consumption. Prototype sensors constructed from this material can meet an exacting standard, the 2012 1 s INTERMAGNET standard, for magnetic observatories.

We developed a serialized small-diameter hydraulic fracturing in situ stress measurement system, which enables series measurement of small-sized boreholes for in situ stress and has the advantage of a simple and lightweight structure, short testing time, high success rate, and low requirements for rock integrity and pressurization equipment. This system has important practical value and economic significance for accurately determining the in situ stress state of deep development areas.

Heat storage in the soil is difficult to measure due to vertical heterogeneity. To improve measurements, we designed a 3D-printed probe that uses fiber-optic distributed temperature sensing to measure a vertical profile of soil temperature. We validated the temperature measurements against standard instrumentation. With the high-resolution data we were able to determine the thermal diffusivity of the soil at a resolution of 2.5 cm, which is much higher compared to traditional methods.

Magnetic field measurements in space can be contaminated by stray magnetic fields from their host satellite. We present an automated tool for measuring the magnetic field generated by potential satellite and instrument components to identify those that may degrade the measurements taken on orbit. This tool is designed for use by the Tandem Reconnection and Cusp Electrodynamics Reconnaissance Satellites (TRACERS) Small Explorers mission and is currently being used for mission design activities.

Data recorded with transient electromagnetics are typically gated to improve the signal-to-noise ratio. Gating corresponds to low-pass filtering of data with the shape of the gate giving the frequency response. We show that standard gate shapes can lead to significant correlation between gates caused by distortion from VLF radios. A multi-objective cost function is used to select optimum gate shapes with less influence from radio noise. Performance is demonstrated using synthetic and field data.

This paper presents a design for a 3D-printed rechargeable electrode that measures self-potential (SP) in different types of laboratory experiments. It is small, cheap, robust, and stable, and it offers the same performance as custom-machined laboratory standards. The use of 3D printing technology makes the electrode more versatile and cost-effective than traditional laboratory standards. Examples of its use under both low and high pressure have been included, as have 3D-printable designs.

Motivated by recent community interest in a satellite mission to the atmospheric lower thermosphere and ionosphere (LTI) region (100–200 km altitude), the DIPCont project is concerned with the reconstruction quality of vertical profiles of key LTI variables using dual- and single-spacecraft observations. The report introduces the probabilistic DIPCont modeling framework, demonstrates its usage by means of a set of self-consistent parametric non-isothermal models, and discusses first results.