Lower Cretaceous nannofossils of ODP Holes 113-682B and 113-693A

Organic-rich, moderately to sparsely nannofossiliferous Lower Cretaceous claystones ("black shales") were cored at two Ocean Drilling Program Leg 113 sites on the continental slope of East Antarctica off Dronning Maud Land. A 39 m section at Site 692 yielded a Neocomian assemblage of limited diversity with rare Cyclagelosphaera deflandrei, Diadorhombus rectus, and Cruciellipsis cuvillieri, and is probably Valanginian in age. A 70-m section at Site 693 is assigned to the Rhagodiscus angustus Zone (late Aptian-early Albian in age). The latter zone is represented at DSDP sites on the Falkland Plateau, but equivalents to the Neocomian section are absent there, probably due to a disconformity. Watznaueria barnesae is the dominant species at both ODP sites, but it shares dominance with Repagulum parvidentatum at Site 693, where they total 70%-90% of the assemblage; their dominance is attributed to a paleogeographic setting within a restricted basin rather than to postdepositional dissolution of other species. The evolutionary development of this restricted basin and its eventual ventilation in early Albian times is discussed in terms of the regional stratigraphy and the breakup and dispersal of southwestern Gondwanaland. One new species, Corollithion covingtonii, is described.

Middle Eocene to Pleistocene calcareous nannofossils of ODP Leg 113 holes

Long sequences of Upper Cretaceous through Quaternary sediments rich in calcareous and siliceous microfossils were recovered at Ocean Drilling Program Sites 689 and 690 on Maud Rise off East Antarctica. These sites have become the southernmost anchor in the Atlantic Basin for bio-, magneto-, chemostratigraphic, and paleobiogeographic studies. ODP Sites 692 and 693 on the Weddell Sea margin of East Antarctica and Site 696 on the South Orkney microcontinent of West Antarctica yielded calcareous nannofossils within some stratigraphic intervals. Sites 691, 692, 694, 695, and 697 did not recover Cenozoic calcareous nannofossils. Calcareous nannofossil biostratigraphy suggests a major hiatus across the Paleogene/Neogene boundary at Sites 689 and 690, and two additional hiatuses in the middle Eocene-lower Oligocene section at Site 690. Correlation with magnetostratigraphy reveals: the last occurrence (LO) of Reticulofenestra umbilica at Maud Rise is over 1 m.y. younger than that at the middle-latitude sites; the LO of Isthmolithus recurvus is synchronous in the middle-latitude and high-latitude areas (about 34.8 Ma); Reticulofenestra oamaruensis ranges from 38.0 to 36.0 Ma at Maud Rise; Reticulofenestra reticulata has a shorter range at Maud Rise (42.1 to 38.9 Ma) than at the middle-latitude DSDP Site 516; the range of Chiasmolithus oamaruensis is diachronous over different latitudes; and the LO of Chiasmolithus solitus is a good datum at 41.3 Ma from 30°S to 65°S in the South Atlantic Ocean. Comparison of calcareous nannofossil abundances in a latitudinal transect shows: Reticulofenestra bisecta is a temperate-water species and its LO, which crosses below that of Chiasmolithus altus at Maud Rise, is not applicable for the Paleogene/Neogene boundary in high southern latitude areas; Clausicoccus fenestratus is rare or absent at Maud Rise and can not be used as a marker; Coccolithus formosus is a warm-water species which disappeared earlier toward higher latitudes. Calcareous nannofossil assemblages indicate that by at least the middle Eocene, surface water temperatures became considerably lower in the high southern latitudes than in the middle-latitude areas and that there have been more extreme cold events in the high latitudes during the Neogene. Bicolumnus ovatus n. gen., n. sp. is proposed in this paper.

Early Cretaceous palynomorphes from ODP Hole 113-692B

Detailed descriptions of in situ ?Valanginian to Albian Antarctic palynofloras are presented from Weddell Sea claystones with high percentages of organic matter ("black shales") and intercalated volcanic ash layers. The claystones were recovered from two sites (ODP Leg 113, Sites 692 and 693) on the continental margin of Dronning Maud Land. Palynological investigations of these Cretaceous sediments revealed a ?Valanginian-Hauterivian age for the Site 692 sediments and an Aptian-Albian age for Site 693. This paper is focused on the palynomorphs of Site 692. Miospores, dinoflagellate cysts, and acritarchs are listed and compared with early Cretaceous microfloras from the Antarctic Peninsula, Australia, and South America. The dinocyst assemblage of Site 692 seems to be very similar in composition to an assemblage from the South Shetlands (?Valanginian-Hauterivian-Barremian). It also agrees well with associations described from early Early Cretaceous sequences from the Perth Basin, southwestern Australia. According to the Australian miospore zonation schemes, the sporomorph flora from Site 692 belongs to the South Australian Foraminisporis wonthaggiensis Zone (early Valanginian to Hauterivian) or the lower part of the dinocyst Muderongia Superzone (Valanginian to Hauterivian).

Sapientia, 1974, Vol. XXIX, nº 113 (número completo)

Contenido: El Esse y el Intelligere divino, fundamento universal e inmediato de todo ser y de toda verdad y entender participados en Santo Tomás / Octavio N. Derisi – Saint Thomas contre l’agnosticisme / F. Van Steenberghen – Trascendentalidad de la belleza en el pensamiento de Santo Tomás / José R. Sanabria -- ¿Navaja de Ockham o navaja de Santo Tomás? / J. E. Bolzán – Notas y comentarios -- Bibliografía

Diário da Constituinte [gravação de vídeo] : [programa n. 113]

O esboço da nova Constituição está pronto. Bernardo Cabral (PMDB-AM) relata que o esboço reflete exatamente o que foi decidido nas comissões temáticas. Sobre a reforma agrária, Fernando Henrique Cardoso (PMDB-SP) relata que o texto permite emendas que propiciem a manutenção da produção e o acesso à terra. Os direitos individuais também sofreram modificações e Nelson Jobim (PMDB-RS) relata que os conceitos foram bem sistematizados e fundamentados. O esboço da Constituição foi entregue ao presidente da Assembleia Nacional Constituinte (ANC), Ulysses Guimarães (PMDB-SP) e será reexaminado por todos os membros da Comissão de Sistematização da ANC. Na sessão O Povo Pergunta, cidadão quer saber como fica a questão do emprego. Domingos Leonelli (PMDB-BA) responde que houve um avanço considerável com a redução da jornada de trabalho para 40 horas semanais. José Walter Filho, coordenador do Sine-DF, diz que a questão do desemprego é estrutural e o próprio sistema estatal de emprego não chega a atender 2% do desemprego a nível nacional. Aloísio Vasconcelos (PMDB-MG) acredita que o desemprego está associado a políticas nacionais e que uma política de emprego se faz necessária, ao invés de políticas econômicas que geram emprego ou desemprego, dependendo da ocasião . Virgílio Galassi (PDS-MG) entende que o desemprego depende também do empregador. Celso Dourado (PMDB-BA) relata que deve-se evitar a política monetarista que valoriza o capital, não o trabalho. Olívio Dutra (PT-RS) afirma que dentro do capitalismo brasileiro há formas de minimizar o desemprego.

Diário da Constituinte [gravação de vídeo] : [programa n. 692]

Fundo da Assembleia Nacional Constituinte 1987/88 - Câmara dos Deputados, Centro de Documentação e Informação, Coordenação de Arquivo.