RN State Research Articles

ASPECTOS HIDROGEOQUÍMICOS E CLASSES DE ÁGUA DO AQUÍFERO CÁRSTICO JANDAÍRA PARA IRRIGAÇÃO, BARAÚNA, RN

The Barauna region is situated on the West part of the Potiguar Basin, in the semi-arid domain of the RN State. Its geology comprehends mainly carbonate rocks (calcareous and dolomites) of the Jandaira Formation whose age is attributed to the Superior Cretaceous. This geological unit constitutes the karst Jandaira Aquifer, which is the main water supply source to human use and irrigation. The Jandaira Aquifer develops different levels of karst in the different sectors of the area, affecting the groundwater potentialities and its quality. In this article aspects in relation to the groundwater use and salinization are presented, highlighting the groundwater use to irrigation. It was developed using data obtained from geophysical studies, wells cadastre, topographic studies and the interpretation of the hydrochemistry data. In the Northern and Western sectors of Barauna the karsts are more expressive. In this case the water is Ca-HCO3 type water, with low salinity and in most of the cases it is good to human use and irrigation (classes C2S1T1 e C2S1T2 to irrigation); To the Southern part of Barauna, where the karsts are less expressive, the groundwater salinity is high, Ca-Mg-Cl type water and the quality suffers a certain restriction to human use and irrigation (Class C3S1T3).

Coeficientes de vacinação anti-aftosa na ULSAV de Parnamirim, RN, no período de 2001 a 2004

The structure of Animal Health Defense unit from Rio Grande do Norte state (RN), northeastern Brazil, consists of six Local Units for Animal and Vegetal Health (ULSAV). Due to the importance of foot and mouth disease for cattle exploration, this aim to make a survey of the indexes of vaccination in the campaigns against foot and mouth disease at region attended by ULSAV-Parnamirim city, RN. The study was done from September to December of 2004. Data were obtained from archives of the State Secretary of Agriculture, Livestock Production and Fishing from RN, concerning the indexes of vaccination of the campaigns of 2001, 2002, 2003 (1st and 2nd stages) and 2004 (1st stage) of the cities of ULSAV-Parnamirim city. In accordance with the data, it can be affirmed that all indexes of vaccination at second stages of the campaigns were lower than those from the first stage. Among non vaccinated animals, the majority was of upper than 4 months of age, which can reach indexes of almost 30%, mainly in the second stages of the campaign. This makes the epidemiological situation of RN state delicate in front of the international agencies for animal health and control and eradication of foot and mouth disease. Keywords: Foot and mouth disease, vaccination, control

Silica enrichment, graphic granite and aquamarine growth: a new exploration guide

Granitic pegmatites are traditionally known to contain graphic, perthitic and myrmekitic intergrowths related to quartz and K- and Na- feldspars. They are further considered to characterise the pegmatite types distinguishing them from the granites and other related plutonic rock types. Graphic granite is accepted also as a synonym to granitic pegmatite. Systematic studies, by the author and colleagues, on the granitic pegmatite gem deposits have permitted the definition of two aquamarine gem provinces in ENE Brazil, one in the NeoProterozoic and the other in the Archaean sequences. Potash feldspars in the pegmatites in the former show perthitic intergrowths, whereas in the latter graphic intergrowth dominates with anomalously coarse centimetric quartz along the cleavages of K-feldspar. Several granitic pegmatites hosted in Archaean complex, in Lages Pintadas Aquamarine Province, Santa Cruz, RN State, present this texture-structure. Graphic intergrowth is attributed to the eutectic crystallization, succeeded by hydrothermal fluids with silica enrichment permitting the growth through diffusion and nucleation of quartz and along cleavages of potash feldspar. In the Archaean terrain, the abundance of recycled chert forming metapsammitic migmatites traversed by numerous quartz veins and coarse graphic granites, has contributed to the growth of beryl and also the aquamarines.

Considerações sobre as influências de uma tectônica cenozóica na pesquisa e prospecção de recursos hídricos - o exemplo do litoral sul de Natal-RN, Brasil

<p>Pesquisas no âmbito da neotectônica no litoral leste do Estado do Rio Grande do Norte caracterizaram , com base em dados geológicos, geofísicos e geomorfológicos , uma estruturação afetando o Grupo Barreiras (de idade Cenozóica) . No presente trabalho procurou-se abordar as influências dessa estruturação na Hidrologia , particularmente na pesquisa e prospecção de águas subterrâneas. Investigações hidrogeológicas realizadas na área de abrangência do Aquifero Sistema Dunas-Barreiras (que abastece Natal e várias outras cidades do litoral leste do Estado) delimitaram algumas zonas de alta transmissividade associando os aspectos "litologia", "hidrodinâmica " e, principalmente , "espessura do aquífero". Este último é aqui mostrado como resultante do condicionamento estrutural do Sistema Dunas-Barreiras , o que parece ser a causa de elevadas produtividades nas captações da CAERN "Granja Recreio" e "Pamarnirim", por exemplo, sob influência do <em>Graben </em>Papary.</p>