Geothermal potential and genetic mechanisms of the geothermal system in the mountainous area on the northern margin of north china

Geothermal resources as clean and renewable energy can be utilized for agriculture, tourism, and industry. The assessment of geothermal potential and the study of genetic mechanism of the geothermal system is an essential part of geothermal resource development. In this study, 16 steady-state temperature logs are obtained in the mountainous area on the northern margin of North China. Thermal conductivity and heat production rates are tested or collected from more than 200 rock samples of these wells and outcrops around the study area. Based on these data, for the first time, the detailed delineations of temperature distributions, genetic mechanisms of geothermal systems, and resource potential of Hot Dry Rock in the study area are achieved. The heat flow map indicates a low heat flow state with an average value of 53.1 mW/m2 in the study area, which is lower than the average value of 62.5 mW/m2 in mainland China. The distribution of hot springs in the area is mainly controlled by fault systems. Heat flow only exhibits a minor effect on the temperature of hot springs and geothermal wells. On this basis, the deep temperature distribution within 3–10 km depths of the study area is calculated using the one-dimensional steady-state heat conduction equation. With it, the reservoir depths of hot springs are estimated to be 3–5 km with temperatures ranging from 70°C to 110°C. Furthermore, a conceptual model for the geothermal system in the study area is derived. According to the results, Northeastern Chengde and northern Beijing exhibit the highest temperatures at all depths. Similar patterns are observed in the temperature distribution maps and the heat flow map, which suggest that the deep temperature distribution is mainly controlled by regional heat flow. With the depth increases, the temperature shows larger variation at each depth level, which is possibly caused by the heterogeneity of crustal composition. According to our resource assessment by volumetric method, the exploitable potential of Hot Dry Rock within the depth of 7–10 km of the study area is equivalent to about 3.1 × 1011 tons of standard coal, but the barrier is still existing for development under the current technical and economic conditions.

Combining Argo and Satellite Data Using Model-Derived Covariances: Blue Maps

Blue Maps aims to exploit the versatility of an ensemble data assimilation system to deliver gridded estimates of ocean temperature, salinity, and sea-level with the accuracy of an observation-based product. Weekly maps of ocean properties are produced on a 1/10°, near-global grid by combining Argo profiles and satellite observations using ensemble optimal interpolation (EnOI). EnOI is traditionally applied to ocean models for ocean forecasting or reanalysis, and usually uses an ensemble comprised of anomalies for only one spatiotemporal scale (e.g., mesoscale). Here, we implement EnOI using an ensemble that includes anomalies for multiple space- and time-scales: mesoscale, intraseasonal, seasonal, and interannual. The system produces high-quality analyses that produce mis-fits to observations that compare well to other observation-based products and ocean reanalyses. The accuracy of Blue Maps analyses is assessed by comparing background fields and analyses to observations, before and after each analysis is calculated. Blue Maps produces analyses of sea-level with accuracy of about 4 cm; and analyses of upper-ocean (deep) temperature and salinity with accuracy of about 0.45 (0.15) degrees and 0.1 (0.015) practical salinity units, respectively. We show that the system benefits from a diversity of ensemble members with multiple scales, with different types of ensemble members weighted accordingly in different dynamical regions.

Challenges of Measuring Abyssal Temperature and Salinity at the Kuroshio Extension Observatory

The deep ocean is severely undersampled. Whereas shipboard measurements provide irregular spatial and temporal records, moored records establish deep ocean high-resolution time series, but only at limited locations. Here, highlights and challenges of measuring abyssal temperature and salinity on the Kuroshio Extension Observatory (KEO) mooring (32.3°N, 144.6°E) from 2013 to 2019 are described. Using alternating SeaBird 37-SMP instruments on annual deployments, an apparent fresh drift of 0.03–0.06 psu was observed, with each newly deployed sensor returning to historical norms near 34.685 psu. Recurrent salinity discontinuities were pronounced between the termination of each deployment and the initiation of the next, yet consistent pre- and postdeployment calibrations suggested the freshening was “real.” Because abyssal salinities do not vary by 0.03–0.06 psu between deployment locations, the contradictory salinities during mooring overlap pointed toward a sensor issue that self-corrects prior to postcalibration. A persistent nepheloid layer, unique to KEO and characterized by murky, sediment-filled water, is likely responsible for sediment accretion in the conductivity cell. As sediment (or biofouling) increasingly clogs the instrument, salinity drifts toward a fresh bias. During ascent, the cell is flushed, clearing the clogged instrument. In contrast to salinity, deep ocean temperatures appear to increase from 2013 to 2017 by 0.0059°C, whereas a comparison with historical deep temperature measurements does not support a secular temperature increase in the region. It is suggested that decadal or interannual variability associated with the Kuroshio Extension may have an imprint on deep temperatures. Recommendations are discussed for future abyssal temperature and salinity measurements.

The map of permanent natural electric field of Russia

The article describes a direct connection between the natural electric potential and the dynamics of the temperature of volcanoes using the examples of observation of the natural electric potential on the surfaces of volcanoes. If the upper part of the volcano is hotter, positive potential anomalies are recorded, and conversely, if the lower part of the volcanoes is hotter, negative anomalies of the same potential are recorded. At the same time, the temperature processes occurring at great depths, as a rule, are closely related to long-lived deep faults. Therefore, observations of the natural potential over these faults will allow controlling the dynamics of deep temperature processes. Given this new direction of the natural potential method and its effective application in the search for non-ferrous metal ores, there is a need to create the map of the natural electrical potential of Russia. As a result, small-scale map would allow us more precise limitation of ore fields and purposefully search for previously undiscovered deposits of metal ores. In addition, a small-scale map would make it possible to most accurately track the development of deep tectonic fault zones and to study them in relation to volcanic activity and seismic events. In this regard, the method of natural electric potential hodograph is considered as one of the possible ways to predict seismic events.

Capacitive resistive electric transfer modifies gait pattern in horses exercised on a treadmill

Background Capacitive resistive electric transfer (CRET), a radiofrequency at 448 kHz, resulted in increased superficial and deep temperature and hemoglobin saturation, faster elimination of metabolic and inflammatory products and enhanced sport performance in humans. This research aims to investigate whether the application of CRET affects the locomotor pattern in horses and to assess whether an accumulative effect appears when two CRET sessions are applied two consecutive days. Methods Nine horses were subjected to two CRET sessions applied in both right and left sides of neck, shoulder, back and croup. The horses were exercised on a treadmill, at walk and at trot, before CRET application and at 2, 6 and 12 h after. A second CRET session was applied next day, and the animals were evaluated again at the same times (i.e. at 26, 30 and 36 h after the first session). Between 5 and 7 days later, the same horses were subjected to a sham procedure and they were evaluated in the same times as in the CRET experiment. During treadmill exercise, locomotor parameters were measured with a triaxial accelerometer fixed in the pectoral region and in the sacrum midline. Results The sham procedure did not affect any of the accelerometric variables studied. CRET applications resulted in greater total powers, which resulted in absolute increased dorsoventral, mediolateral and longitudinal powers. However, a reduction in dorsoventral power expressed as a percentage of total power was found. Stride regularity increased. The greater total power resulted in longer stride length and because the velocity was kept fixed on the treadmill, stride frequency decreased. An accumulative effect of CRET application was only found in stride length and frequency. Conclusions It appears that CRET is a useful technique to enhance power and to elongate the stride at defined walk and trot velocities. The effect of these changes on performance should be studied for horses competing in different sport disciplines.