Consulta: subjectFacets:"Late Aptian"
Registros recuperados: 3
Data/hora: 09/06/2024 13:38:19

A new angiosperm leaf morphotype from the Early Cretaceous (Late Aptian) of San Luis Basin, Argentina
Provedor de dados: 41
Autores: Puebla,Gabriela G.
A new fossil angiosperm leaf morphotype, "LC-Microphyll trifoliate", from the Late Aptian La Cantera Formation, central western Argentina, is described. The leaf remains occurred at the type section of the formation within a low diversity macrofloral association. Fossils are found mainly as isolated small size leaflets (0.3-1.5 cm long). The leaves are pinnately compound (imparipinnate, trifoliate), the leaflets have pinnately lobed margin, first vein category pinnate, secondary veins craspedodromous opposite to subopposite ending at the apex of lobes and an intramarginal vein. "LC-Microphyll trifoliate" is among the earliest record of leaf remains possibly allied to the eudicots and one of the first evidence of angiosperm with compound leaves.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Angiosperm; Eudicots; Late Aptian; La Cantera Formation; Argentina.
Ano: 2009
URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S0002-70142009000300009

Petrography of gypsum-bearing facies of the Codó Formation (Late Aptian), Northern Brazil
Provedor de dados: 42
Autores: Paz,Jackson D.S.; Rossetti,Dilce F.
An original and detailed study focusing the petrography of evaporites from the Late Aptian deposits exposed in the eastern and southern São Luís-Grajaú Basin is presented herein, with the attempt of distinguishing between primary and secondary evaporites, and reconstructing their post-depositional evolution. Seven evaporites phases were recognized: 1. chevron gypsum; 2. nodular to lensoidal gypsum or anhydrite; 3. fibrous to acicular gypsum; 4. mosaic gypsum; 5. brecciated gypsum or gypsarenite; 6. pseudo-nodular anhydrite or gypsum; and 7. rosettes of gypsum. The three first phases of gypsum display petrographic characteristics that conform to a primary nature. The fibrous to acicular and mosaic gypsum were formed by replacement of primary gypsum, but...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Evaporite; Petrography; Paleolake; Sabkha; Late Aptian; São Luís-Grajaú Basin.
Ano: 2006
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652006000300014

Facies analysis of the Codó Formation (Late Aptian) in the Grajaú Area, Southern São Luís-Grajaú Basin
Provedor de dados: 42
Autores: Rossetti,Dilce F.; Paz,Jackson D.S.; Góes,Ana M.
Facies descriptions of the Codó Formation in the Grajaú area are provided for the first time, and its sedimentary characteristics compared to those from the Codó area to allow paleoenvironmental reconstructions. Deposits in the Grajaú area include evaporites, limestones and argillites bearing features indicative of a shallow, low energy, subaqueous, saline environment exposed to meteoric and/or capillary conditions. Flooding-evaporative concentration-desiccation cycles suggest a saline pan complex surrounded by extensive evaporitic mudflats. The location of the system, whether coastal or inland, is a matter open for debate. However, the later hypothesis is favored considering: 1. Sr isotopic data, with values higher than those expected for Late Aptian...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Evaporite; Paleoenvironment reconstruction; Lacustrine; Late Aptian; Facies analysis; São Luís-Grajaú Basin.
Ano: 2004
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652004000400012