Geochemistry of Hawaiian volcanics

The "Ko'olau" component of the Hawaiian mantle plume represents an extreme (EM1-type) end member of Hawaiian shield lavas in radiogenic isotope space, and was defined on the basis of the composition of subaerial lavas exposed in the Makapu'u section of Ko'olau Volcano. The 679 m-deep Ko'olau Scientific Drilling Project (KSDP) allows the long-term evolution of Ko'olau Volcano to be reconstructed and the longevity of the "Ko'olau" component in the Hawaiian plume to be tested. Here, we report triple spike Pb isotope and Sr and Nd isotope data on KSDP core samples, and rejuvenation stage Honolulu Volcanics (HV) (together spanning ~2.8 m.y.), and from ~110 Ma basalts from ODP Site 843, thought to be representative of the Pacific lithosphere under Hawai'i. Despite overlapping ranges in Pb isotope ratios, KSDP and HV lavas form two distinct linear arrays in 208Pb/204Pb-206Pb/204Pb isotope space. These arrays intersect at the radiogenic end indicating they share a common component. This "Kalihi" component has more radiogenic Pb, Nd, Hf, but less radiogenic Sr isotope ratios than the "Makapu'u" component. The mixing proportions of these two components in the lavas oscillated through time with a net increase in the "Makapu'u" component upsection. Thus, the "Makapu'u" enriched component is a long-lived feature of the Hawaiian plume, since it is present in the main shield-building stage KSDP lavas. We interpret the changes in mixing proportions of the Makapu'u and Kalihi components as related to changes in both the extent of melting as well as the lithology (eclogite vs. peridotite) of the material melting as the volcano moves away from the plume center. The long-term Nd isotope trend and short-term Pb isotope fluctuations seen in the KSDP record cannot be ascribed to a radial zonation of the Hawaiian plume: rather, they reflect the short length-scale heterogeneities in the Hawaiian mantle plume. Linear Pb isotope regressions through the HV, recent East Pacific Rise MORB and ODP Site 843 datasets are clearly distinct, implying that no simple genetic relationship exists between the HV and the Pacific lithosphere. This observation provides strong evidence against generation of HV as melts derived from the Pacific lithosphere, whether this be recent or old (100 Ma). The depleted component present in the HV is unlike any MORB-type mantle and most likely represents material thermally entrained by the upwelling Hawaiian plume and sampled only during the rejuvenated stage. The "Kalihi" component is predominant in the main shield building stage lavas but is also present in the rejuvenated HV. Thus this material is sampled throughout the evolution of the volcano as it moves from the center (main shield-building stage) to the periphery (rejuvenated stage) of the plume. The presence of a plume-derived material in the rejuvenated stage has significant implications for Hawaiian mantle plume melting models.

Geochemistry and petrology of ODP Site 136-843 basalts

About 13 m of Cretaceous, tholeiitic basalt, ranging from normal (N-MORB) to transitional (T-MORB) mid-ocean-ridge basalts, was recovered at Ocean Drilling Program Site 843 west of the island of Hawaii. These moderately fractionated, aphyric lavas are probably representative of the oceanic basement on which the Hawaiian Islands were built. Whole-rock samples from parts of the cores exhibiting only slight, low-temperature, seawater alteration were analyzed for major element, trace element, and isotopic composition. The basalts are characterized by enrichment in the high field strength elements relative to N-MORB, by a distinct positive Eu anomaly, and by Ba/Nb and La/Nb ratios that are much lower than those of other crustal or mantle-derived rocks, but their isotope ratios are similar to those of present-day N-MORB from the East Pacific Rise. Hole 843A lavas are isotopically indistinguishable from Hole 843B lavas and are probably derived from the same source at a lower degree of partial melting, as indicated by lower Y/Nb and Zr/Nb ratios and by higher concentrations of light and middle rare earth elements and other incompatible elements relative to Hole 843B lavas. Petrographic and trace-element evidence indicates that the Eu anomaly was the result of neither plagioclase assimilation nor seawater alteration. The Eu anomaly and the enrichments in Ta, Nb, and possibly U and K relative to N-MORB apparently are characteristic of the mantle source. Age-corrected Nd and Sr isotopic ratios indicate that the source for the lavas recovered at ODP Site 843 was similar to the source for Southeast Pacific MORB. An enriched component within the Cretaceous mantle source of these basalts is suggested by their initial 208Pb/204Pb-206Pb/204Pb and epsilon-Nd-206Pb/204Pb ratios. The Sr-Pb isotopic trend of Hawaiian post-shield and post-erosional lavas cannot be explained by assimilation of oceanic crust with the isotopic composition of the Site 843 basalts.

Comentario a la sentencia de la Rota Romana del 27/10/2006, Coram R. P. D. Mauricio Monier, ponente prot. N. 17.557 – sent. 136/06

Introducción: La presente Sentencia contempla la nulidad de un matrimonio en que las partes tuvieron un noviazgo de más de cuatro años y una convivencia matrimonial de dos años y medio, en la que no hubo hijos. La separación de las partes definitiva tuvo lugar porque el convenido era incapaz de instalar una vida verdaderamente conyugal. Se me solicita un comentario a esta Sentencia, publicada en su texto original latino y en su traducción castellana, cuando ya existe un breve, pero medular y excelente comentario del Revdo. Mons. Dr. Alejandro W. Bunge, Juez de la Rota, publicado en el libro “Pius et Prudens”, con el título de “Una Sentencia integradora”1. Además, el indicado comentario, se encuentra en el contexto de un generoso elogio a la persona de quien suscribe por la preocupación acerca de la indebida omnipresencia de las causas psíquicas de nulidad matrimonial en los Tribunales eclesiásticos, cuando muchas veces es más ajustada a la verdad y se deberían tener en cuenta, las causas éticas, concretamente las exclusiones de algunos de los fines o de las propiedades esenciales del matrimonio que tiene lugar por parte de los cónyuges...

Diário da Constituinte [gravação de vídeo] : [programa n. 136 A]

Descrição do Projeto Nhundiaquara, uma experiência de reforma agrária no município de Morretes, no litoral do Paraná, baseada na distribuição de terras de uma antiga usina de açúcar. Assentados falam das suas terras e do trabalho. A assistência aos assentados é feita pela ACARPA (Associação de Crédito e Assistência Rural do Paraná), cujos técnicos fornecem sementes, ensinam técnicas de cultivo e dão apoio financeiro. Apresentação de dados sobre projetos de assentamentos criados pelo INCRA no Brasil. Assentados acreditam na reforma agrária e pedem aos deputados e senadores da Assembleia Nacional Constituinte (ANC) melhores condições de trabalho aos colonos.

Diário da Constituinte [gravação de vídeo] : [programa n. 136]

Proibir a fabricação de armas nucleares no Brasil e preservar as terras indígenas são as principais reivindicações dos cientistas à Assembleia Nacional Constituinte (ANC). Reunidos na 39ª Reunião Anual da Sociedade Brasileira para o Progresso da Ciência (SBPC), os pesquisadores querem debater suas propostas com os constituintes. Carolina Bori, Presidente da SBPC quer apresentar as propostas da SBPC, que não interessam só aos cientistas, mas à sociedade brasileira. A SBPC vai enviar duas proposta de emendas populares. O Reitor da USP José Goldemberg é contra a fabricação de armas nucleares no país. Os cientistas querem também a manutenção da proposta que dá poderes somente ao Congresso Nacional para autorizar a mineração nos territórios indígenas. Manuela C. da Cunha, Presidente da Associação Brasileira de Antropologia, defende que somente a União tenha o privilégio da pesquisa e lavra em áreas indígenas. Wanderlino T. da Carvalho, Presidente da Coordenação Nacional de Geólogos, propõe que as terras indígenas se tornem reservas nacionais de minérios, cuja exploração não é urgente para as necessidades do país no momento. Aílton Krenak, representante da União das Nações Indígenas, afirma que as comunidades indígenas querem ter o direito de esboçar um projeto próprio de futuro e que deverão ter assegurado o direito à terra e aos recursos naturais nela existentes . A Comissão de Sistematização discute o pedido de anulação da aprovação do projeto que proíbe a conversão da dívida externa em investimento de capital estrangeiro no país. O Líder do Governo Carlos Sant'Anna (PFL-BA) diz que a matéria é assunto do Congresso e não da Constituinte. Paulo Ramos (PMDB-RJ), autor do projeto, discorda.

On the feeding of freshwater ostracods. [Translation of: Zoologicheskij zhurnal, 27(2), 1948, 125-136]

The present work appertains to a series of investigations in the field of trophodynamics of water bodies conducted by the department of hydrobiology ”Mosrybvtuza” under the leadership of Prof. Director N.S. Gaevska. Usually with quantitative collections of benthos ostracoda are hardly taken account of. But with the employment of special methods it is possible to be convinced that they are encountered in massive numbers. The role of ostracods in the nutrition of fish is recognised as important by many authors. On the question of the feeding of ostracods, in the literature there are only the fragmentary indications about the occurrence in the gut of ostracods of algae (diatoms, desmids) and detritus. The study of the feeding of ostracods was conducted both by the method of dissecting the guts of ostracods taken from natural waters, and by the method of feeding ostracods under laboratory conditions with a variety of food objects. Moreover, with a view to revision of obtained quantitative data, for determination of food requirements of ostracods the respiration method was applied.

Experiments on the production of a highly dispersible calcium carbonate. ('Experimental section' only) [Translation from: Szklo i Ceramiki 30, 133-136, 1979]

This short translation summarises experiments on the production of a highly dispersible precipitate of calcium carbonate. The translation covers the 'Experimental section' (of the original larger paper) only.