Constraining complex aquifer geometry with geophysics (2-D ERT and MRS measurements) for stochastic modelling of groundwater flow

Stochastic modelling is a useful way of simulating complex hard-rock aquifers as hydrological properties (permeability, porosity etc.) can be described using random variables with known statistics. However, very few studies have assessed the influence of topological uncertainty (i.e. the variability of thickness of conductive zones in the aquifer), probably because it is not easy to retrieve accurate statistics of the aquifer geometry, especially in hard rock context. In this paper, we assessed the potential of using geophysical surveys to describe the geometry of a hard rock-aquifer in a stochastic modelling framework. The study site was a small experimental watershed in South India, where the aquifer consisted of a clayey to loamy-sandy zone (regolith) underlain by a conductive fissured rock layer (protolith) and the unweathered gneiss (bedrock) at the bottom. The spatial variability of the thickness of the regolith and fissured layers was estimated by electrical resistivity tomography (ERT) profiles, which were performed along a few cross sections in the watershed. For stochastic analysis using Monte Carlo simulation, the generated random layer thickness was made conditional to the available data from the geophysics. In order to simulate steady state flow in the irregular domain with variable geometry, we used an isoparametric finite element method to discretize the flow equation over an unstructured grid with irregular hexahedral elements. The results indicated that the spatial variability of the layer thickness had a significant effect on reducing the simulated effective steady seepage flux and that using the conditional simulations reduced the uncertainty of the simulated seepage flux. As a conclusion, combining information on the aquifer geometry obtained from geophysical surveys with stochastic modelling is a promising methodology to improve the simulation of groundwater flow in complex hard-rock aquifers. (C) 2013 Elsevier B.V. All rights reserved.

Alvará, porque Vossa Alteza Real he servido revogar toda a prohibição, que havia, de fabricas, e manufacturas no Estado do Brazil, e dominios ultramarinos, na forma acima exposta : para Vossa Alteza Real João Alvares de Miranda Varejão o fez

Apresenta o alvará de 12 de abril de 1808, do Príncipe Regente D. João, que revoga o Alvará de 5 de janeiro de 1785, de Maria I, que extinguia a manufatura de tecidos no Brasil.

Voyage dans les provinces de Saint-Paul et de Sainte-Catherine

As Voyages... são estudos completos, abrangendo todos os aspectos das regiões percorridas; servem de subsídio ao estudo das condições de vida no Brasil no século passado. "Fonte primordial de informações sobre os prédios coloniais do Rio de Janeiro, Minas Gerais, São Paulo, Santa Catarina e Goiás. Poucas obras no gênero atingem o valor de Saint-Hilarire. São clássicas e indispensáveis para o estudo do sul do Brasil, antes da Independência" segundo Borba de Moraes

A Sermon occasioned by the death of Mrs. Sarah R. Baker

Funeral sermon

A Sermon on the occasion of the death of Mrs. Mary Chapman Halsey

Memorial Sermon

In southern India : a visit to some of the chief mission stations in the Madras presidency / by Mrs. Murray Mitchell.

http://www.archive.org/details/insouthernindivi00mitcuoft

The martyrs of Golbanti : or missionary heroism illustrated in the lives of Rev. John and Mrs. Houghton, of East Africa / by Robert Brewin.

http://www.archive.org/details/martyrsofgolbant00brewiala

Mission tales in the days of the dons, by Mrs. A.S.C. Forbes ... with nine full page illustrations and decorative drawings, by Langdon Smith.

http://www.archive.org/details/missiontalesday00forbrich

Memoir of Mrs. Sarah L. Huntington Smith, late of the American mission in Syria / by Edward W. Hooker.

http://www.archive.org/details/memoirofhuntingt00hookuoft

Memoir of Mrs. Ann H. Judson, wife of the Rev. Adoniraum Judson, missionary to Burmah, including a history of the American Baptist Mission in the Burman Empire.

http://www.archive.org/details/memoirofmrsannhj00judsuoft