Papers by Diego Kietzmann
The outcrops of La Manga Formation located close to Bardas Blancas area in the south of Mendoza P... more The outcrops of La Manga Formation located close to Bardas Blancas area in the south of Mendoza Province allow a reconstruction of the shallow sedimentary environment of an Oxfordian carbonate ramp, developed in the Neuquén basin in west-central of Argentina. La Manga Formation is composed of greyish wackestone/packstone (outer ramp), greyish grainstone/packstone (middle ramp), light grey grainstone and subordinate packstones (shoal), grey and white coralline limestones (inner ramp margin), bioclastic, and peloidal wackestones-packstones from inner ramp. The sedimentary record shows a hierarchical sequence stratigraphic organization, which implies sea-level changes of different frequencies (see Palma et al., this symposium). Several aspects of diagenesis were investigated including micritization, cement types, cathodoluminescence and stable isotopes. The earliest diagenetic process is represented by micritized peripheral areas of bioclasts and an early isopachous to bladed calcite. This cement where found lines skeletal and non skeletal particles. Their fibrous habit and non-luminescent features are interpreted to be of early phreatic marine origin suggesting oxidizing conditions. Other varieties of cements are granular calcite and syntaxial cement. The granular calcite cement that either completely fills the dissolved aragonitic shells of molluscs and interparticles pores suggesting a freshwater phreatic origin... This cement display an early non-zoned dull luminescence, followed by zoned, bright luminescence and late dull luminescence of the cavities fillings. Each zone represents the precipitation of calcite from pore waters with different chemical compositions, from reducing to slightly reducing, and reducing conditions during a shallow burial meteroric-phreatic diagenetic environment. The transition to the shallowburial diagenetic realm is indicated by a typical non-bright-dull cathodoluminescence sequence. Syntaxial calcite cement on echinoid fragments shows a similar luminescence patterns. Granular calcite cement has a δ18 O value that ranges between -2.6 %0 to -6.8 %0 PDB and δ 13 C values from -2.50%0 to -4.12%0 PDB. These values are consistent with meteoric phreatic diagenesis. Physical compaction processes include deformation and breakage of particles, while chemical compaction includes both pression-solution and microstylolites development. Results strongly indicate that the diagenetic environment changed from marine phreatic through meteoric-phreatic, interrupted by a period of emergence.
Revista De La Asociacion Geologica Argentina, Jun 1, 2007
La Formación Chachao (Valanginiano), presente en el área del anticlinal Malargüe, está compuesta ... more La Formación Chachao (Valanginiano), presente en el área del anticlinal Malargüe, está compuesta por wackestones, packstones, y escasos grainstones y mudstones ricos en fauna bentónica de bivalvos (Eryphila sp., Ptychomia sp., Pecten sp., Pinna sp., Trigonia sp., Cuccullaea sp.), ocasionales amonites (Olcosthepanus sp.) y serpulidos (Sarcinella sp., Parsimonia sp.), y que fueron depositados en una rampa carbonática (Palma y Lanés, 2001). Los fenómenos diagenéticos estudiados incluyen micritización, disolución y estabilización mineralógica de los componentes, y fases tempranas de cementación representadas por cemento micrítico e isopáquico. Los fenómenos diagenéticos tardíos incluyen calcita granular y cemento sintaxial. Las características petrográficas y geoquímicas sugieren que la precipitación de estos tipos de cementos han sido producidas en un ambiente freáticometeórico.
Proceedings of the 3rd Unconventional Resources Technology Conference, 2015
Se analizan los depósitos de la Formación Vaca Muerta en la sección del arroyo Loncoche, ubicada ... more Se analizan los depósitos de la Formación Vaca Muerta en la sección del arroyo Loncoche, ubicada 20 km al sur de la ciudad de Malargüe (35º36`S; 69º37`W), donde la unidad constituye un sistema de rampa homoclinal de bajo gradiente topográfico dominada por facies de cuenca y rampa externa. Se caracteriza por la alternancia rítmica de margas y lutitas con mudstones, wackestones, packstones y floatstones bioclásticos y su extensión temporal ha sido determinada entre el Tithoniano temprano y el Berriasiano tardío por la presencia de las zonas de asociación de amonites de Virgatosphinctes mendozanus en la base y Spiticeras damesi en el techo (Kietzmann, 2007).
Los depósitos carbonaticos peritidales de la Formación La Manga (Oxfordiano) en el área del río S... more Los depósitos carbonaticos peritidales de la Formación La Manga (Oxfordiano) en el área del río Salado (Mendoza) están caracterizados por presentar una ciclicidad a escala centimétrica, donde se advierte una notable somerización (upward shallowing cycles). Estos ciclos son comunes en diferentes sectores de la cuenca y se reconocen dos tipos: (1) ciclos subtidales someros con evidencias de emersión y (2) ciclos peritidales con exposición subaérea marcada.
The orogenic front at 37ºS has been mainly formed through at least two contraccional stages, as i... more The orogenic front at 37ºS has been mainly formed through at least two contraccional stages, as inferred from the exhumed major angular unconformities at the Late Eocene and the Late Miocene times respectively. A Late Cretaceous event is restricted to the hinterland zones in the Main Cordillera. A series of syntectonic sedimentary packages, that thin to the east is identified through a detailed description of the cannibalized westernmost Neogene foreland basin associated with the Sierra de Reyes. Their detrital microscopic and macroscopic descriptions reveal that the Neogene basin was fed from the west and particularly from the eastern Sierra de Reyes slope at the time of mountain incision. Detrital composition of the upper section reveals that a metamorphic component is present, implying that a domain further east has been exhumed, and therefore that the westernmost foreland basin has been cannibalized. This also implies that exhumation previous to Miocene times should have been minimum in the area, since the Neogene succession represents a complete unroofing. The structural cross sections show Neogene shortening of about 20%, leaving in comparison Eocene contraction as negligible.
Sedimentologic and sequence stratigraphic analysis of the Vaca Muerta and Quintuco Formations in ... more Sedimentologic and sequence stratigraphic analysis of the Vaca Muerta and Quintuco Formations in Chos Malal area, Neuquén Basin. The Vaca Muerta-Quintuco system (early Tithonian – early Valanginian) is a broad shallowingupward sedimentary cycle consisting of dark bituminous shales, marls, limestones, and sandstones, cropping out in the Neuquén Basin, west-central Argentina. This paper analyzes three sections in Chos Malal area, northern Neuquén province. Detailed facies analysis allows to differentiate six facies associations, representing basinal to middle ramp facies of a homoclinal carbonate ramp system (Vaca Muerta Formation), and basinal to shoreface facies of a mixed carbonate/siliciclastic shelf system (Quintuco Formation), prograding westward from the eastern margin of the basin. Two sequence hierarchies are recognized, including five composite depositional sequences and thirteen high-frequency sequences. These results are useful as analogs in nearby areas, since the shelf b...
Resumen: Se analizan los depósitos de tormenta de dos secciones estratigráficas de la Formación V... more Resumen: Se analizan los depósitos de tormenta de dos secciones estratigráficas de la Formación Vaca Muerta (Tithoniano-Valanginiano) en el área de Bardas Blancas, sur de la provincia de Mendoza. Estos depósitos incluyen: a) depósitos con estratificación entrecruzada de bajo ángulo; b) depósitos con estratificación entrecruzada hummocky de pequeña y gran escala; y c) depósitos laminados con gradación normal intralámina. Las secuencias completas con HCS están compuestas por tres unidades (Sa, Sb y Sc) asociadas al evento de tormenta y una unidad que incluye depósitos de post-tormenta y de buen tiempo (Sd). La comparación con ejemplos actuales y ejemplos del registro, permite estimar un rango batimétrico de 25 a 50 m para los depósitos con estratificación entrecruzada hummocky. Asimismo se discuten posibles orígenes alternativos relacionados con inestabilidades en la interfase de la picnoclina y los efectos de la compactación sobre la preservación de las texturas y estructuras primarias de los depósitos de la Formación Vaca Muerta.
The Neuquén Basin was a Mesozoic back-arc basin located on the western margin of Gondwana. During... more The Neuquén Basin was a Mesozoic back-arc basin located on the western margin of Gondwana. During Late Jurassic and Early Cretaceous a series of marine sequences were developed throughout the basin, in response to rapid ingression from Pacific Ocean, and are grouped under the Mendoza Mesosequence. Basin to mid-ramp cyclic facies of the Early Tithonian -Early Valanginian Vaca Muerta Formation are exposed in the southern Mendoza area of the Neuquén Basin, Argentina. In this study we analyze five sections of this unit, from north to south: La Manga Creek (173 m, partially), Loncoche Creek (316 m), Cuesta del Chihuido (185 m), La Mula Creek (176 m) and Cara Cura Creek (320 m).
Se presentan los resultados del análisis estratigráfico, sedimentológico, secuencial y bioestrati... more Se presentan los resultados del análisis estratigráfico, sedimentológico, secuencial y bioestratigráfico realizados en los depósitos jurásicos de la Formación La Manga , aflorantes en el arroyo de La Manga, depocentro Atuel .
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Papers by Diego Kietzmann