Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-07-25T19:35:26Z No. of bitstreams: 1 SilviaAmorimTerra_DISSERT.pdf: 8312476 bytes, checksum: 1f02e20db0fedd2c8dc5413db2f0b262 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-08-01T20:19:56Z (GMT) No. of bitstreams: 1 SilviaAmorimTerra_DISSERT.pdf: 8312476 bytes, checksum: 1f02e20db0fedd2c8dc5413db2f0b262 (MD5) / Made available in DSpace on 2016-08-01T20:19:56Z (GMT). No. of bitstreams: 1 SilviaAmorimTerra_DISSERT.pdf: 8312476 bytes, checksum: 1f02e20db0fedd2c8dc5413db2f0b262 (MD5) Previous issue date: 2015-03-27 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPq / O presente trabalho objetiva a caracteriza??o de rochas carbon?ticas da Forma??o Janda?ra, termalmente afetadas no contato com intrus?es b?sicas do Pale?geno e Ne?geno, na regi?o dos munic?pios de Pedro Avelino e Janda?ra (RN), nordeste do Brasil. Para o estudo em tela, foram utilizados dados de campo, microsc?picos, difra??o de raios-X, microssonda eletr?nica e litogeoqu?mica de rocha total. Os calc?rios n?o afetados termalmente s?o wackstones, grainstones e packstones. Podem constituir fragmentos de foramin?fero bent?nico, espinhos de equinoderma, ostracode, algas, bivalve, gastr?pode, pel?ides e intraclastos. A porosidade encontrada se enquadra nos tipos vugular, intrapart?cula, interpart?cula, intercristalina e m?ldica. Como minerais essenciais, tem-se calcita, anquerita e dolomita; como fases detr?ticas, citam-se montmorilonita, pirita, limonita, quartzo e microclina. Os calc?rios termalmente afetados apresentam granula??o muito grossa a muito fina e colora??o cinza clara a escura. Os componentes fossil?feros desaparecem totalmente, e a porosidade tende a desaparecer. Com os dados obtidos, infere-se que os prot?litos carbon?ticos seriam calc?rios calc?feros a dolom?ticos, ambos com pequena quantidade de minerais do grupo das argilas. Os calc?rios cristalinos de prot?lito dolom?tico cont?m calcita rombo?drica e bastante sulfeto e ?xido / hidr?xido de ferro, tornando as rochas bem mais escuras. Os carbonatos de prot?lito calc?tico mostram grande varia??o de granula??o em fun??o do grau de recristaliza??o, que aumenta na dire??o do contato com os corpos b?sicos. Neste grupo, foram identificados os minerais pirometam?rficos lizardita e espin?lio nas amostras pouco e moderadamente afetadas, e espin?lio e espurrita nas fortemente afetadas, al?m da calcita que ocorre em todos os casos. O contexto geol?gico (intrus?es rasas de diab?sios), a presen?a dos minerais pirometam?rficos espurrita e olivina (pseudomorfisada para lizardita, serpentina, brucita), e compara??o com diagramas da literatura permitem estimar temperaturas e press?es em torno de 1050-1200?C e 0,5-1,0 kbar, respectivamente, para PTOTAL=PCO2. O resfriamento p?s-intrus?o teria propiciado a remobiliza??o de por??es de mat?ria org?nica do sedimento original e libera??o de fluidos metassom?ticos / hidrotermais, ensejando a abertura do sistema metam?rfico, com eventual contribui??o de elementos qu?micos das unidades hospedeiras (arenitos, folhelhos) e das pr?prias intrus?es b?sicas. Isto favoreceria a hidrata??o de fases pr?vias, resultando em forma??o de serpentina, clorita e brucita. Os resultados mostram a forte influ?ncia do calor aportado por intrus?es b?sicas no pacote sedimentar. Considerando que na por??o offshore da bacia ocorrem soleiras com espessura de at? 1000 m, o entendimento do pirometamorfismo poder? ser de grande utilidade na compreens?o e dimensionamento desses dep?sitos. / The present study aims the characterization of thermally affected carbonate rocks from Janda?ra Formation in contact with Paleogene and Neogene basic intrusions in the region of the Pedro Avelino and Janda?ra municipalities (RN), northeastern Brazil. For this study, field, petrographic, x-ray diffraction, electron microprobe, and whole rock litogeochemistry data of carbonates were undertaken. The thermally unaffected limestones are classified like wackstones, grainstones and packstones. They may constitute carbonates grains of benthic foraminifera, echinoderm spines, ostracods, algae, corals, bivalves, gastropods, peloids and intraclasts. The porosities are classified like vug, intraparticle, interparticle, intercrystal and moldic types. The major minerals are calcite, ankerite and dolomite; the detrital are montmorillonite, pyrite, limonite, quartz and microcline. The thermally affected limestones are very coarse to very fine-grained and light to dark gray color. The fossiliferous components totally disappear, and the porosity tends to disappear. With the data obtained, it can be inferred that the carbonate protoliths would be calciferous to dolomitic limestones, both with small amount of clay minerals. Crystalline carbonates from dolomitic protolith have rhombohedral calcite and iron oxides / hydroxides, making the rocks much darker. The carbonates from calciferous protolith have a wide variation of grain size according to the recrystallization degree, increasing toward contact with the basic bodies. In this group, it was identified the minerals lizardite and spinel in weakly to moderately affected samples, and spinel and spurrite in strongly affected rocks, as well as calcite, that occur everywhere. The geological context (shallow level diabase intrusions), the crystallization of the pyrometamorphic minerals spurrite and olivine, and comparison with diagrams from the literature allow estimating temperatures and pressures around 1050-1200 ?C and 0.5-1.0 kbar, respectively, for PTOTAL=PCO2. The post-intrusion cooling would have afforded the releasing of metasomatic / hydrothermal fluids, allowing the opening of the metamorphic system, with possible contribution of chemical elements from host units (sandstones, shales) and from basic intrusions. This would induce hydration of previous phases, allowing the formation of serpentine, chlorite and brucite. The results discussed here reveal the strong influence of the heat from basic intrusions within the sedimentary pile. Whereas in the offshore portion of the basin occur sills with up to 1000 m thickness, the understanding of pyrometamorphism might be useful for understanding and measuring the thermally affected rocks.

Made available in DSpace on 2014-12-17T14:57:52Z (GMT). No. of bitstreams: 1 JeanCSA.pdf: 2642121 bytes, checksum: ee65334424753f93878bcb16392de432 (MD5) Previous issue date: 2009-03-24 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / The types of products manufactured calcium silicate blocks are very diversified in its characteristics. They include accessory bricks, blocks, products in dense material, with or without reinforcements of hardware, great units in cellular material, and thermal insulating products. The elements calcium silicate are of great use in the prefabricated construction, being formed for dense masses and hardened by autoclaving. This work has for objective develop formulations that make possible the obtaining of calcium silicate blocks with characteristics that correspond the specifications technical, in the State of the Rio Grande of the North, in finality of obtaining technical viability for use in the civil construction. The work studied the availability raw materials from convenient for the production of calcium silicate blocks, and the effect of variations of the productive process on the developed products. The studied raw materials were: the quartz sand from the city of S?o Gon?alo do Amarante/RN, and two lime, a hydrated lime and a pure lime from the city of Governador Dix-Sept Rosado/RN. The raw materials collected were submitted a testes to particle size distribution, fluorescence of X rays, diffraction of X rays. Then were produced 8 formulations and made body-of-test by uniaxial pressing at 36 MPa, and cured for 7 hours at about 18 kgf/cm2 pressing and temperature of approximately 180 ?C. The cure technological properties evaluated were: lineal shrinkage, apparent density, apparent porosity, water absorption, modulus of rupture flexural (3 points), resistance compression, phase analysis (XRD) and micromorphological analysis (SEM). From the results presented the technological properties, was possible say that utilization of hydrated lime becomes more viable its utilization in mass limestone silica, for manufacture of calcium silicate blocks / Os tipos de produtos s?lico-calc?rios fabricados s?o muito diversificados em suas caracter?sticas. Eles incluem tijolos, blocos, produtos acess?rios em material denso, com ou sem refor?os de ferragem, grandes unidades em material celular, e produtos isolantes t?rmicos. Os elementos s?lico-calc?rios s?o de grande utiliza??o na constru??o pr?-fabricada, sendo formados por massas densas e endurecidos em autoclave. Este trabalho teve como objetivo desenvolver formula??es que possibilitem a obten??o de blocos s?lico-calc?rios com caracter?sticas que correspondem ?s especifica??es t?cnicas, no Estado do Rio Grande do Norte, na finalidade de obter viabilidade t?cnica para uso na constru??o civil. O trabalho estudou a disponibilidade de mat?rias-primas convenientes para a produ??o de blocos s?lico-calc?rios, e o efeito das varia??es do processo produtivo sobre os produtos desenvolvidos. As mat?rias-primas estudadas foram: uma areia quartzosa oriunda do munic?pio de S?o Gon?alo do Amarante/RN, e duas cal, uma cal hidratada e uma cal virgem oriundas do munic?pio de Governador Dix-Sept Rosado/RN. As mat?rias-primas coletadas foram submetidas a ensaios de distribui??o de tamanho de part?cula, fluoresc?ncia de raios X, difra??o de raios X. Em seguida foram produzidas 8 formula??es e confeccionados corpos-de-prova por prensagem uniaxial a 36 MPa, e curados durante 7 horas em press?o de aproximadamente 18 kgf/cm2, e temperatura de aproximadamente 180?C. As propriedades tecnol?gicas de cura avaliadas foram: retra??o linear, massa espec?fica aparente, porosidade aparente, absor??o de ?gua, m?dulo de ruptura ? flex?o em 3 pontos, resist?ncia a compress?o, an?lise fases (DRX) e an?lise micromorfol?gica (MEV). A partir dos resultados apresentados das propriedades tecnol?gicas, foi poss?vel afirmar que a utiliza??o da cal hidratada torna-se mais vi?vel sua utiliza??o em massas s?lico-calc?rias, para fabrica??o de blocos s?lico-calc?rios