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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 describe a new drill for glaciers and ice sheets. Instead of drilling down into the ice, via mechanical action, our drill melts into the ice. Our goal is simply to pull a cable of temperature sensors on a one-way trip down to the ice–bed interface. Here, we describe the design and testing of our drill. Under laboratory conditions, our melt-tip drill has an efficiency of ∼ 35 % with a theoretical maximum penetration rate of ∼ 12 m h⁻¹. Under field conditions, our efficiency is just ∼ 15 %.

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.

This paper proposes a new online data transmission technology for marine controlled-source electromagnetic (MCSEM) transmitters. The technology enables high-precision data acquisition, storage, and ethernet file transmission and offers significant convenience. This technology has the potential to revolutionize the application of MCSEM transmitters in marine explorations and to offer significant convenience.

The study investigates how low-cost technology can be applied in data-scarce catchments to improve water resource management. More specifically, we investigate how drone technology can be combined with low-cost real-time kinematic positioning (RTK) global navigation satellite system (GNSS) equipment and subsequently applied to a 3D hydraulic model so as to generate more physically based rating curves.

We propose a new type of power station unit with wireless data transmission capability, which was not supported by same type of instrument as on the market. Based on this, a novel distributed geophysical data acquisition architecture is also proposed. The proposed instrument loads more stations than the industry-leading LAUL-428 while providing additional wireless data transmission and narrowband Internet of Things remote control.

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.

Multiple geologic hazards, such as landslides and earthquakes, arise when solids and fluids coexist and deform together. We designed an experimental apparatus that allows us to observe such deformation in 3D. The first results show how fluids and solids deform and break at the same time, allowing us to study the impact of both materials on deformation distribution and speed. Making these processes visible has the potential to improve risk assessments associated with geological hazards.

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.