The present project aims at the processing and interpretation of magnetic data along the basement adjacent to the Sergipe-Alagoas Sedimentary, Southern Borborema Province, and northeast Brazil. The magnetic and geological studies were developed simultaneously to make a magnetic modeling of the crustal domains and their tectonic relationships to construct a model of the geothermal structure of the crust for the region. The first part of the study consisted in to delineate contacts and border of the geologic formation. These magnetic sources have signals with various amplitudes that originate from different geometric sources, situated at different depths and with different magnetic properties. The second part consisted in to estimate of the depth of the main domains and Curie point in the study region and the knowledge of the Curie depth allows the subsequent estimation of the geothermal gradient and thermal flow in the region. The results obtained from the analysis of the magnetic anomalies shows the Curie point depth of from the 13 up to 33 km. The Curie point depth indicates the bottom depth of magnetic sources and reflects the thermal gradient and the observed heat flow data. The thermal gradient varies from the 15°C/km up to 35°C/k and the heat flow varies from the 38 mW/m² up to 90 mW/m² heat flow. We compared results to the available the layers carry a magnetic signature and plunge at a significant angle, a detailed magnetic investigation was used to map the very precise surface geology. The present result was compared with the tectonic and heat flow data.
Our aim is to develop a computational model of the corrosion forms known as scallops and flutes, common in karst environment.
This model is designed to take in account dynamical interactions between successive forms, which has previously never be done, and to be as simple as possible.
We present preliminary results corresponding to numerical simulations that have been run during February 2018.
The evolution of scallops and flutes is summarized in some simple equations that model how the length of a form evolves, how too large forms split into smaller forms and how too small forms are erased by larger ones. These equations are used in programs written in C language. They enable to investigate how a system of numerous scallops or flutes evolves and to investigate the corresponding statistical distribution.
The preliminary results we present are very encouraging because of their good quantitative agreement with the well-known Curl relationship in the case of steady flows. When the velocity of the water (or air) responsible for the formation of scallops or flutes change, the model predicts that the average size of the forms changes too. However, in such a situation, the Curl relationship is not always accurately verified.
This progressive model depends upon few parameters and does not require huge computing power. Further comparisons with field data may render it even more realistic, particularly regarding the statistical distributions it generates.
Aims: The dangerous portion of ultraviolet radiation is widely believed to be completely absorbed by the atmosphere before reaching Earth’s surface. Our objective is to make multiple measurements at Earth’s surface of the solar irradiance spectrum in the range 200-400 nm.
Methods: We made numerous measurements of the solar irradiance spectrum in the range 200-400 nm at an elevation of 56 m with International Light Technologies ILT950UV Spectral Radiometer mounted on a Meade LXD55 auto guider telescope tripod and mount assembly.
Results: Our multifold measurements of solar irradiance spectra demonstrate conclusively that all wavelengths in the spectral range 200-400 nm reach Earth’s surface, contrary to the widespread perception that all UV-C and the majority of UV-B never reach the surface. We confirm the surface UV-C measurements of D’Antoni et al. (2007) that were disputed, based on faulty computer model calculations of atmospheric ozone, and thereafter ignored by the geoscience community.
Conclusions: The veracity of our data and D’Antoni et al. (2007)’s data call into question the validity of atmospheric ozone models. Further, we call into question the simplistic supposition of the Montreal Protocol that chloro-fluoro-hydrocarbons are the primary cause of ozone depletion, and point to the very heavy burden of halogens introduced into the atmosphere by ongoing jet-sprayed coal-fly-ash geoengineering. We demonstrate that satellite-based LISIRD solar spectra irradiance at the top of the atmosphere is badly flawed with some regions of the spectrum being less intense than measured at Earth’s surface. That calls into question any calculations made utilizing LISIRD data. We provide introductory information on the devastating effects of UV-B and UV-C on humans, phytoplankton, coral, insects and plants. These will be discussed in greater detail in subsequent articles.
It is important to combine different methods to quantify the soil loss in a mountainous sub-watershed. Geographic Information System (GIS), Remote Sensing and Revised Universal Soil Loss Equation (RUSLE) were adopted to estimate the annual soil loss in the highest watershed in Morocco. The High valley of Tifnoute is a part of a national park of Toubkal and constitutes a best choice for such application. The availability of some ecological resources (Lake ifni) and the population that suffers from yearly loss of their agricultural areas constitute a primary need for erosion mapping, which make it’s the first one in the study area. The deterioration of ecological heritage and agricultural fields by sediment filling are the major problems in the study area.
The RUSLE factors (R, K, LS, C and P) were computed using Tropical Rainfall Measuring Mission (TRMM), soil analysis, topographic map, remote sensing and digital elevation model (DEM). The resultant map of annual soil erosion with RUSLE method show a real problem of soil loss in the study area, and high soil erosion zones are located in the middle and in upstream of the watershed. The sediments transported constitues a big problem for Ifni lake located in downstream of the sub-watershed. The article highlights the application of RUSLE, GIS and RS methods in the mapping of annual soil loss estimation in mountainous area. The results constitue an essential database to offer a planning of conservation practices to control soil erosion.
This study evaluated the groundwater quality in Umuebulu IV, Oyigbo, using water quality index (WQI) with a view to ascertain its suitability for domestic and drinking water purposes. Groundwater samples were collected from ten (10) functional boreholes in the study area. These water samples were subjected to a comprehensive physicochemical analysis using standard method. The water quality index of the area was calculated using weighted arithmetic mean. Fifteen (15) parameters were analyzed but only nine (9): pH, Electrical conductivity, Total Dissolved Solids, Chloride, Nitrate, Sulphate, Phosphate, Total Hardness and Sodium which were detected during the analysis was used for the WQI calculation. The WQI values of 18.69, 13.86, 17.67, 16.01, 16.99, 14.69, 12.94, 16.50, 13.09 and 11.78 were recorded from BH1 to BH10 respectively which shows that that all the water samples were in the excellent category. The pH values ranging from 5.47 - 5.82 shows slight acidity and as such would require treatment to bring it to an acceptable limit. However, the low values of the WQI have been found to be mainly due to the low values of the chemical parameters analyzed suggesting that the groundwater is suitable for domestic and drinking purpose.