The Manglaralto aquifer is located at the north of the province of Santa Elena, Ecuador, its importance is based on the source of supply for the sector. The objective of this work is to characterize the waters of this hydrogeological system by means of hydrochemical techniques (Piper and Stiff diagrams) and their correlation with the geology of the area, as well as the determination of marine intrusion. The methodology used is based on the concentrations of the major ions, which have been obtained by the water-rock interaction, where the geological analysis helps to understand the conceptual hydrogeological model. The obtained results indicate that there are two groups of waters: in the part closest to the interior of the basin with facies mainly bicarbonate and calcium-sodium, while nearest the sea shows markedly calcified calcium facies, and the existence of marine intrusion in the well closest to the coastline.
Coastal aquifers are strategic and fundamental in the development of touristic areas. The coastal aquifer within the Manglaralto River Basin in Ecuador is essential, as it is the only source of water supply for a large part of the northern part of the Santa Elena province. It is a semi-arid region where high volumes of water are pumped from the aquifer, causing a significant drawdown of groundwater levels, thus affecting the water quality. This work aims to characterize the characteristics of groundwater in the coastal aquifer using hydrochemistry and stable isotopes to propose a hydrogeological conceptual model. The methodology for determining the chemical and isotopic characteristics of groundwater follows the following scheme: (i) studies of ionic concentrations using the Piper diagram, (ii) assessment of the origin of salinity through the Cl/Br ratio, the presence of seawater intrusion through the Hydrochemical Facies Evolution Diagram HFE-D, (iii) characterization of precipitation events using stable isotopes (18O and 2H), and, (iv) development of a hydrogeological conceptual model of the study area. The results indicate that in the basin there are mixing processes of the existing water in the aquifer with recharge water, direct cation exchange processes in the freshening process during recharge, and evaporation in the unsaturated zone. A conceptual model of the flow system in the basin is built, based on the mentioned processes. The main conclusions are: seawater intrusion is present in the areas of the wells located closest to the coast, urban activity through septic tanks is affecting the quality of the aquifer, and rainfall is highly relevant in the different hydrochemical and isotopic processes that operate in the basin.
Landslides, earthquakes, and other natural events can change the landscape and generate human and economic losses, affecting transportation and public service infrastructure. In every geotechnical project, the investigation phase plays a fundamental role in reducing the risk of occurrence and mitigating catastrophes. As a result, governments have created entities to study disasters and identify triggering factors that generate huge losses worldwide. This research aims to conduct a systematic review of the relationship between geotechnics and disasters through bibliometric techniques, scientific production evaluation, and case studies analysis to recognize key topics, methods, and thematic development of the research worldwide. The research methodology consisted of three steps: (1) Database analysis, selection, and combination, (2) bibliometric analysis, and (3) systematic review using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) method. The systematic review with bibliometric analysis collected data from 1973 to 2021, with 1299 academic publications indexed in the Scopus and WoS database. These results indicated a growing trend of annual publications on disasters and their relationship with geotechnical studies, highlighting current issues and technological innovation. The main research trends in disaster risk assessment were topics mainly linked to landslides, earthquakes, liquefaction, and inappropriate analysis models with applications of geophysical methods, laboratory tests, remote sensing, and numerical models.
Zaruma is a city with a mining tradition, located at 1,200 m above sea level, with natural conditions of high slopes. The existence of galleries under the city centre, originated by old and illegal mining works, has created conditions that impact the mining-society relationship of a technical-social nature, with concern about subsidence city's urban area. The areas of the Humberto Molina Hospital and its surroundings, such as the SJ Bosco School, have been affected by different geodynamic events, which has damaged infrastructure. The aim of this research is to assess the study area through geotechnical surveying, processing laboratory information, and direct field observation, using the approach of pre-design proposals containing technical solutions to ensure the safety of buildings. The methodology used consists of: (i) information processing and field surveys; (ii) drilling and pits work for sampling and determination of in-situ properties and laboratory work; (iii) interpretation of the results obtained, assessment of stability conditions through Spencer's method and consideration of the influence of underground work; (iv) analysis of susceptibility to slippage using the methodology of various authors; and (v) proposal of the pre-design of the technical security solutions. The study verified that the stability of the works are influenced, both by the physiographic factors and the incidence of nearby illegal underground work. Slope stability can be aggravated in extreme situations by seismic action, heavy rainfall, and migration of underground voids in the direction of the works. Susceptibility analysis determined that the terrain is in a stable condition, as the soil studied was categorized as medium to very good quality. Among the recommendations for the remediation of the Humberto Molina Hospital, it is suggested control of the drainage of rainwater and wastewater, use of vegetation, change of current fill, strengthening with concrete, and other basic considerations regarding building structures should be undertaken, associated with direct observation and geotechnical studies.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.