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Correctly determining the orbit of Earth-orbiting satellites requires to account multiple background effects which appear in the system Earth. Usually, these effects are introduced by various complex force models, which are not always easy to handle. We publish and validate a data set of commonly used models to make it easier to track down potential issues when applying such background forces in orbit and gravity field determination.

Fracture networks are often self-similar and are defined by a fractal dimension. However, two such networks with the same fractal dimension may have subtle differences in their clustering attributes that lead to distinct connectivity and flow behavior. This research shows that rather than the fractal dimension, lacunarity, a parameter quantifying scale-dependent clustering, is a better proxy for fracture connectivity as well as flow responses and, is relatively easy to compute than connectivity.

Fumarolic fields with near-surface temperature <100°C are very common features of volcanoes. Their space/time variability is controlled by hydro-meteorological conditions, vapor flow and permeability, reflecting changes of volcanic activity. Since the thermal monitoring of these fumaroles is a low cost, up-to-date technique, it has been successfully applied in volcanic surveillance programs of Italian active volcanoes, giving useful insights on the evolution of their activity state.

In this paper the main results of the regional program Rad Campania for the monitoring and the assessment of the radon risk are analyzed. An analysis of all data collected is presented in order to improve the radon reserach field and enrich the scientific literature of important results and new methodologies to be applied and extended in other similar cases.

We studied the subsoil structure of the Campi Flegrei area using both spectral ratios and array techniques (f-k and MSPAC) applied to seismic noise recorded by three different array. By means of joint inversion of dispersion curve and spectral ratio we obtained a Vs model, that is in a good agreement with the stratigraphic information available in the area. In areas such as Campi Flegrei the definition of the velocity model is a crucial issue to characterize the physical parameters of the medium

Energy supply in Germany is subject to a profound change. The present paper addresses the German potential of storing excess energy from renewable power sources in the geological subsurface. Wind and solar electricity can be transformed into hydrogen, and with carbon dioxide subsequently into methane. The current potential for combined subsurface storage of methane and carbon dioxide allows to store far more than required to date and is estimated to provide the entire coverage in 2050.

This study presents a framework for regional smart energy planning for the optimal location and sizing of small hybrid systems. By using an optimization model – in combination with weather data – various local energy systems are simulated using the Calliope and PyPSA energy system simulation tools. The optimization and simulation models are fed with GIS data from different volunteered geographic information projects, including OpenStreetMap.

Storm Xaver in December 2013 had a high gust field that caused transportation and energy infrastructure impacts in northern Europe. There was a strong storm surge across the North Sea basin that was higher than the 1 Feb 1953 surge in certain places. For some stations in the UK and Denmark, water levels exceeded the 1000 year return period level. Similar to previous winter storms, there is an indication of large waves in coastal areas with potential impacts on offshore energy infrastructure.

Utilization of geothermal reservoirs as alternative energy source is becoming increasingly important worldwide. Here, we studied the surface expression of a warm water reservoir in Waiwera, New Zealand, that has been known for many centuries but remained little explored. Using thermal infrared cameras we were able to show renewed activity of the hot springs on the beachfront and identified faults and fractures as important fluid pathways, as well as individual fluid conducting lithologies.

As national regulator within the German siting process, the Federal Office for the Safety of Nuclear Waste Management (BASE) performs own research on, e.g., geo-scientific questions, methodological aspects of the implementation of the site selection process, and public participation aspects. The results support BASE to fulfil its task according to state-of-the-art science and technology, ensure highest safety-level and are also relevant to other stakeholders of the siting process.

The wettability of reservoir rock is one of the most critical factors affecting the residual saturation and transport properties. In this work, we investigated the wettability of target rock samples using a nuclear magnetic resonance, vapor adsorption, and wetting contact angle technique. Results provided an initial assessment of rock surface wettability and showed correlations between wettability index, rock lithology, and organic matter morphology for target shale formation.

The UNEXUP project aims to improve, test, and commercialize the robotic technology developed within the UNEXMIN project, which is already equipped with enough navigation and geoscientific instrumentation to perform exploration missions in flooded mines. The UNEXUP robot-based service intends to address the needs and requirements from mining companies, geological surveys and other sectors that can benefit this technology.

The ROBOMINERS project develops an innovative technology for the future exploitation of small and difficult to access mineral deposits. A bioinspired robotic miner prototype, able to navigate, explore and mine under several work conditions, makes the exploration of many mineral deposits economically feasible, while reducing social and environmental impacts associated with conventional mining methods. A new mining system tailored to this new technology line is also under development.

We investigate the oscillations of relative sea level through the analysis of tide gauge records collected in the Gulfs of Pozzuoli and Napoli (Southern Italy). The main goal is to provide a suitable resolution model of the sea tides including seiches, tidal bands and non-linear tides. We also target a non-conventional purpose of the tidal analysis, namely extracting from the tide gauge records the volcano-tectonic signal, the vertical ground displacement in the resurgent Campi Flegrei caldera.

For the documentation of time and space variations of water vapor in atmosphere during the Nawdex campaign (fall 2016), a ground network of more than 1200 continuously operation reference GNSS stations has been analyzed. This network spreads from Caribbeans to Morocco through Greenland. This study presents the retrieval of Integrated Water Vapor content from GNSS measurements and their use in the evaluation of the European Centre for Medium-Range Weather Forecasts reanalyses ERAI and ERA5.

We interviewed 12 female students to examine their experiences in geosciences at the male-dominated Universidad de Chile. The experience moved from negative to positive in the transition from the early years of college, during which they experienced gender-based discrimination, to the geoscience major within which the presence of more women improved the environment. We discuss some strategies to increase the satisfaction of female students in science, technology, engineering, and math (STEM).

We investigate the microseismicity occurred at Hengill area, a complex tectonic and geothermal site, where the origin of earthquakes may be either natural or anthropogenic. We use a very dense broadband seismic monitoring network and apply full-waveform based method for location. Our results and first characterization identified different types of microseismic clusters, which might be associated to either production/injection or the tectonic activity of the geothermal area.

Changes to a volcanic edifice and its surroundings can be caused by movements of underground magma, gas or other fluids (typically water). These deformations are usually very small in magnitude, so very sensitive instruments are the only capable of detecting them. A discrimination between deformations caused by volcanic processes in regards to those caused by external sources could help in understanding the volcano dynamics and give scientists a way to forecast volcanic eruptions.

The coordinates of radio telescopes, which are part of the emerging VLBI Global Observing System, were estimated in a least squares unconstrained adjustment. The higher number of observations per time with better sky coverage, which these telescopes can produce, was optimally utilized by testing different intervals for the tropospheric delay estimation. We found that a short estimation interval of 15 min for the tropospheric gradients with a 45 min interval for the zenith wet delay perform best.

A circular city is built upon the principles of circular economy, which key concepts are reduce, reuse, recycle, and recover. However, the sources, types and available quantities of insufficiently used resources in cities are currently not well documented. A site resource inventory of infrastructural and building-specific parameters has the potential to enhance the circular city’s information flow and thus support both companies in their site decisions and municipalities in the planning process.

In our study, we investigate the variability of potential offshore wind power over Europe on time scales of more than 10 years. Detailed spectral analysis of potential offshore wind power capacities over the last century indicates a strong coupling to large climate patterns such as the NAO. Furthermore, combining the wind power potential at the German North Sea and the Portuguese Atlantic coast shows that the variability can be mitigated.

We simulate the deformation of Somma-Vesuvius volcano due to some overpressure sources by means of a finite element 3D code. The goal of these simulations is to investigate the influence of topography and structural heterogeneity on ground deformation. The results suggest that they are key factors governing the ground deformation. Our study clearly demonstrate that a better knowledge of deformation patterns can significantly help in the design of an efficient geodetic network.

Mineral precipitation in filters and heat exchangers can impede geothermal plant operation and cause expensive losses of efficiency. To prevent scaling a biodegradable inhibitor has been applied in a geothermal plant. Water monitoring revealed no significant chemical changes, but an adaption of the microbial community as well as a higher abundance of Bacteria after heat extraction. Laboratory experiments under anaerobic conditions showed that the inhibitor can be almost completely metabolized.

In this work we describe the integrated application of 3D diagnostic methods, i.e. Terrestrial Laser Scanner (TLS), close range photogrammetry (CRP) and ultrasonic tomography supported by petrographic investigations. They were used to implement the diagnostic process of the conservation state of a column of a colonnade in the ancient church of Saints Lorenzo and Pancratio, dating to about the second half of the thirteenth century and located in the old town of Cagliari (Italy).

This study endeavours to improve marine spatial planning abilities and the productivity of potential offshore renewable energy developments by creating a unique geological dataset that can be incorporated into common GIS assessments. To accomplish this, a dataset of 1,858 new and existing points is compiled and used to build a series of gridded outputs. The final model reveals areas of probable seabed stability that could provide useful information to future planning activities.

This study focuses on the comparison of different solar radiation pressure (SRP) strategies combined with a-priori information and empirical SRP parameterization. Analysis of precise orbits as well as estimated empirical SRP parameters based on various SRP strategies shows visible differences and indicates the deficiencies of a-priori model or empirical parameterization. The orbit difference patterns presented in this study may give the view on how to improve the current SRP models.

In this study, a coupled thermo-hydro-mechanical (THM) model is implemented to simulate the processes of heat extraction, reservoir deformation, and groundwater flow in the fractured rock reservoir. The results show that the growth of the number and spacing of fracture zones can effectively decrease the pore pressure difference between injection and abstraction wells; it also increases the production temperature at the abstraction, the service life-spans, and total heat production rate.

In this study, we apply the Genetic Algorithm technique that mimics the natural selection process observed in nature to design optimal layouts for massive wind farms off the southeastern coast of India using real wind data. Our results show that layout optimization leads to large improvements in power generation (up to 28 %), efficiency (up to 34 %), and cost (up to 25 %) due to the reduction in wake losses.

The TRANsport Simulation Environment (TRANSE) has been developed to improve the flexibility for coupling chemical libraries with fluid flow and the transport of heat and chemical species. The Python-based implementation of TRANSE enables users not experienced in low-level programming languages (e.g., C, C++ or FORTRAN) to undertake required code modifications and integrate chemical modules as required. TRANSE has been successfully verified against benchmarks on density-driven fluid flow.

Spectral analysis has been applied to seismic events recorded at Vesuvius volcano to test a new tool for a fast event classification. We computed two spectral parameters, central frequency and shape factor from the spectral moments. The results show that volcano-tectonic earthquakes and low frequency events are distinguishable though the spectral moments. Since the computation of spectral parameters is easy and fast, it may become an effective tool for classification in observatory practice.

Understanding and predicting of subsurface geophysical and geotechnical processes, such as hydrothermal flows and oil and gas production, is limited by the fact that such processes cannot be directly observed. Limited monitoring can often be done only through surface observations including gravimetry and ground uplift or subsidence. The article describes the software that allows to constrain subsurface parameters by the observations at surface.

We compute gravity field solutions from kinematic orbit positions of GRACE. These positions are derived from GPS based observations, and hence, they are contaminated by measurement noise. We present three methods of dealing with the noise in the data to obtain not only high-quality gravity field solutions but also an accurate quality information of the gravity fields.

In order to better understand both the fixation and migration of gases in evaporites, investigations were performed in five horizontal boreholes drilled in an underground potash seam. According to the He-isotopes, a small contribution of mantle gas can be found in the geogenic salt gas. We assume that CO₂ and CH₄ are related to volcanic activity, where they isotopically equilibrated at temperatures of 513 °C to 519 °C about 15 to 16 Ma ago.

Selecting suitable configurations is a key step for Electrical Resistivity Tomography (ERT) surveys. The paper proposes two selection criteria which have been tested on numerical resistivity models, developed for a CO₂ injection experiment at the Svelvik CO₂ field lab in Norway. After the CO₂ injection took place schedule performance is revalued using revised reservoir models. The study shows opportunities and challenges associated with small scale CO₂ injection monitoring using ERT.

We model two kinds of demand for public charging infrastructure: As compensation for the lack of home charging points, and based on points of interest. We combine those two demands with the available parking spaces and generate distributions for possible future charging points. We use a raster-based approach on a municipality’s full grid. The model is compared with three other models in a correlation comparison in order to determine the influence of certain model assumptions and input data.

Depletion of conventional hydrocarbon deposits requires implementation of the enhanced oil recovery methods, particularly based on carbon dioxide injection. The article aims at an accelerated optimisation of such methods performance by means of numerical modelling. We propose an optimisation algorithm based on the construction of a hierarchy of compositional reservoir models. We give examples of the algorithm application and discuss its performance.