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(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Evaluating karst geotechnical risk in the urbanized area of Sete Lagoas, Minas Gerais, Brazil

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Author(s):
Galvao, Paulo [1] ; Halihan, Todd [2] ; Hirata, Ricardo [1]
Total Authors: 3
Affiliation:
[1] Univ Sao Paulo, Inst Geosci, BR-05508080 Sao Paulo, SP - Brazil
[2] Oklahoma State Univ, Sch Geol, Noble Res Ctr 105, Stillwater, OK 74078 - USA
Total Affiliations: 2
Document type: Journal article
Source: HYDROGEOLOGY JOURNAL; v. 23, n. 7, p. 1499-1513, NOV 2015.
Web of Science Citations: 10
Abstract

An increase in groundwater consumption in the municipality of Sete Lagoas (Minas Gerais, Brazil) has induced subsidence and collapse in the last three decades. The area is associated with natural karst conditions. The primary objective of this research was to evaluate and identify the potential subsidence or collapse risk zones. Aerial photographs, lithologic well profiles, optical well logs, and geologic mapping were utilized to categorize risk factors influencing karst subsidence and collapse, which were then applied to an index system. The study showed that the majority of the urbanized area overlies mantled limestone from the Sete Lagoas Formation covered with unconsolidated sediments, contained within a graben, resulting in barrier boundaries for groundwater flow. This structure, together with natural karst processes, explains the location of solutionally enlarged bedding-plane conduits and high hydraulic conductivity in the limestone. Five risks zones in the municipality were identified (negligible, low, moderate, considerable, and high risks) related to geologic and hydrologic risk factors. The urbanized area is located largely in the high risk zone where the majority of the collapse features are located. Additional intensive groundwater extraction in that area will likely generate additional events. (AU)

FAPESP's process: 12/12846-9 - HYDROGEOLOGICAL CHARACTERIZATION AND AN IMPLEMENTATION OF A MANAGEMENT MODEL FOR UNDERGROUND WATER RESOURCES IN AQUIFERS KARST, SETE LAGOAS CITY (MG)
Grantee:Paulo Henrique Ferreira Galvão
Support type: Scholarships in Brazil - Doctorate