Wyniki wyszukiwania - BazTech

1

Recognition of mine water-inrush sources using artificial neural network

Qinglong Zhou, Herrera Juan, Hidalgo Arturo

Mining Science

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2023

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Vol. 30

147--156

EN

In the process of excavating and mining, water-inrush episodes induced by a number of geological or human factors is a complex geological hazard and often lead to disastrous consequences, making an accurate prediction before an inrush accident is difficult because there are so many factors and interactions between factors are related in such hazard, No matter how accurate a risk assessment approach is, it can not 100% guarantee that every water inrush accident can be accurately predicted. Until so far, inrush accidents are still occurring every year all over the world, especially in developing countries. For inrush accidents in underground mining, the first and also the critical step of controlling the accident is to find out the related inrush sources, accurately identifying which aquifer or which water body is directly related to the inrush accident is the critical step of controlling water volume and reducing casualties and economic losses. In this study, method of using artificial neural network (ANN) to identify the water-inrush sources is proposed, by establishing a back propagation neural network (BPNN) to train, test and predict the sample data selected from Jiaozuo mine area, results show that ANN is an effective approach to identify water sources.

2

Evaluation of shallow groundwater quality under impact zones of livestock and poultry farms using self-organizing maps

Chen Jiayu, Gui Herong

Acta Geophysica

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2023

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Vol. 71, no. 5

2465--2479

EN

The shifting of livestock and poultry production systems from traditional small householder farms to semi-intensive and intensive farms has led to a gradual deterioration in the quality of shallow groundwater, which has attracted considerable attention from researchers. In this study, a combination of self-organizing map technology was used to identify the effects of livestock and poultry farms on shallow groundwater hydrochemistry. NO3–N content in the livestock and poultry farm water samples in summer and winter, as well as the NH4–N and NO2–N content in the water samples of livestock and poultry farm, respectively, in winter, were more vulnerable to external influences. Agricultural and industrial activities were important sources of Cl- and SO42- leaching in shallow groundwater in the study area. Silicate weathering is an important source of conventional ions in the shallow groundwater at these two sites. The water quality at livestock farms was mainly affected by farm activities and agricultural pollution in summer and winter, whereas that at poultry farms was mainly affected by industrial sources and natural sources.

3

Hydrochemical characteristics and water quality assessment of Lake Dayet Erroumi – Khemisset, Morocco

El Qryefy Mohamed, Ouardi Jamila, Najy Mohamed, Belghyti Driss, El Kharrim Khadija

Journal of Water and Land Development

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2021

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no. 49

179--187

EN

The objective of this paper is to study the hydrochemical characteristics of Lake Dayet Erroumi (Khemisset, Morocco). Three sampling campaigns were carried out in April, July and November 2019. The temperature, pH and electrical conductivity were measured in situ using Hanna Instruments HI 98280. Concentrations of calcium, magnesium, carbonate, bicarbonate and chloride were analysed by the volumetric method. The atomic absorption technique was used to determine sodium, potassium, nitrate and sulphate. The physico-chemical analysis of the water indicates that the pH is basic. The nitrate and sulphate concentrations show that the water is of good quality according to Moroccan surface water guidelines. Furthermore, the hydrochemical facies of water is of the sodium-chloride type according to the Piper diagram. The value of the electrical conductivity indicates that the lake water has high salinity. The high mineralization of water is explained by the leaching from evaporitic rocks in the region. The principal component analysis shows that the spatial and temporal variation in salinity constitutes the major phenomenon of the hydrochemical characteristics of this lake. Salinity varies inversely with the pH value. The salinity of the water is controlled by abiotic factors (rain and evaporation). However, other parameters (pH, nitrate, carbonate and bicarbonate) depend on biotic factors. Evaporation plays a crucial role in the seasonal variation of the water chemical composition. During wet seasons, the mineralization of water decreases due to dilution by rainwater and the water level of the lake rises (high water period). During dry seasons, lake water evaporates and consequently the mineralization of the water increases, which explains the increase in salinity during the low water period.

4

Hydrochemical characteristics and water quality assessment of groundwater in the Yishu River basin

Liu Jiutan, Wang Min, Gao Zongjun, Chen Qiao, Wu Guangwei, Li Fuquan

Acta Geophysica

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2020

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Vol. 68, no. 3

877--889

EN

Groundwater is the primary source of water for human development in the Yishu River basin, and therefore characterizing groundwater quality is essential for sustainable development of groundwater resources in the region. This study aimed to determine the hydrochemical characteristics and water quality of groundwater in the Yishu River basin by sampling 45 wells in October 2016 and May 2017. Hydrochemical characteristics of groundwater were determined using integrated hydrochemical analysis and the groundwater quality was evaluated based on the water quality index (WQI). Groundwater of the Yishu River basin was characterized as weak alkaline hard water with mean concentrations of total hardness and total dissolved solids of less than 500 mg L−1 and 1000 mg L−1, respectively, and the principal chemical components of groundwater were higher in 2016 than in 2017. A Piper diagram showed that 64.4% of the water samples contained Ca–HCO3 type water and 27% contained mixed water (27%). The dominant processes driving the chemical composition of groundwater were found to be dissolution of silicate and carbonate minerals and cation exchange. The saturation index indicated that carbonate minerals were supersaturated, whereas gypsum, fuorite, and halite were unsaturated. The WQI indicated good groundwater quality in the Yishu River basin, with only one water sample classifed as having "poor" water quality in 2016 and 2017, respectively. However, these samples contained high nitrate concentrations (>200 mg L−1), which may be the result of domestic sewage discharge and/or the use of agricultural fertilizers.

5

Statistical and hydrogeochemical characteristics of the M’Daourouch-Drea Plain’s groundwater, North-East of Algeria

Brahmia A., Brinis A., Nouar T.

Journal of Water and Land Development

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2018

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no. 38

19--26

EN

This work was conducted on 23 samples distributed between springs, wells and boreholes tapping the shallow and deep aquifer in the M'Daourouch-Drea area located in extreme northeast of Algeria. Ca2+, Mg2+, Na+, K+, Cl–, SO4 2–, HCO3 – and NO3 – were analysed. The interpretation of the geological-geophysical data allowed us to highlight two aquifers. The first consists of conglomerates, sandstones, gravels, sands, marls, limestones, lacustrine and alluvial deposits varying in thickness from a few tens to a few hundred meters, representing Neogene- Quaternary filling of the studied basin. The second is more important localized in the cracked and karstified limestones of upper Cretaceous age; these limestones are outcropped on the flanks of the syncline and the borders of the basin. The first aquifer sometimes rests directly on the second which allows hydraulic communication between them. The hydogeochemical and statistical study, with the combination of numerous tools, indicates that the chemistry of groundwater in the M'Daourouch-Drea Plain is controlled both by the dissolution of the minerals of the evaporite formations and those of the carbonate formations.

PL

W pracy przedstawiono wyniki badań, których podstawą były 23 próbki wód podziemnych pochodzących ze źródeł, studni kopanych i wierconych służących czerpaniu wody z płytkiego i głębokiego poziomu wodonośnego na obszarze M'Daourouch-Dréa w północnowschodniej Algierii. W próbkach analizowano stężenie Ca2+, Mg2+, Na+, K+, Cl–, SO4 2–, HCO3 – i NO3 –. Interpretacja danych geologiczno-geofizycznych ujawniła istnienie dwóch poziomów wodonośnych. Pierwszy zbudowany jest z konglomeratów, piaskowców, żwirów, piasków, margli, wapieni i osadów aluwialnych o miąższości od kilkudziesięciu do kilkuset metrów, które reprezentują czwartorzędowe wypełnienie basenu. Drugi, ważniejszy, zlokalizowany jest w spękanych krasowych wapieniach górnej kredy. Wapienie te mają miejscami wychodnie na obrzeżach synkliny i przy granicach basenu. Pierwszy poziom wodonośny zalega w niektórych miejscach nad drugim, co umożliwia łączność hydrauliczną między obydwoma poziomami. Badania hydrogeochemiczne i statystyczne w połączeniu z rozmaitymi narzędziami wskazują, że skład chemiczny wód gruntowych na terenie równiny M'Daourouch-Dréa zależy od rozpuszczania minerałów z formacji ewaporatowych oraz z utworów węglanowych.