Paleoenvironment and age of Los Monos Formation (Devonian), Tarija Basin, Argentina and Bolivia

The objective of this work is to discuss the paleoenvironment and age of the Los Monos Formation, in outcrop and subsurface, along a regional transect (west-east) in the southern sector of the Tarija basin. The lithofacies and ichnofacies of the Alarache, Angosto del Pescado and Balapuca outcrops and core-intervals of the Aguas Blancas xp-13, Ramos x-12, Tartagal x-1 and Tonono x-1 boreholes were analyzed. The definition of lithofacies and ichnofacies allowed us to interpret a shallow to deep marine paleoenvironment (from the offshore-transition, offshore and shelf). Towards the top of the Tonono Formation, the equivalent of the Los Monos Formation in the Chaco-Salteño was defined as a brackish-waters marginal-marine paleoenvironment. The mineralogy of the mentioned sections plus the Vespucio x-1 borehole was analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM), thus the majority elements in clay minerals were also determined from EDAX. Authigenic and detrital clays from SEM-EDAX were recognized. Four clay mineral assemblages were defined (I+Ch; Ch+I; I+K; K+I), where I+K and K+I assemblages characterize the transgressive events within the basin. The palynofacies of the Balapuca, Alarache and Angosto del Pescado outcrops and samples from the Ramos xp-1002, Ramos xp-1011 and Ramos xp-1012 boreholes were defined, the dominance of terrestrial palynomorphs was recognized with variable participation of marine palynomorphs, according to a shallow marine paleoenvironment with shoreline shifts. Two transgressive events were identified during the late Eifelian-early Givetian and the late Givetian-early Frasnian, which are characterized by an increase in marine components and clay assemblages of I+K and K+I. The palynological associations pont to a late Eifelian-early to middle Givetian age for the Los Monos Formation in the study area. The analysis of illite crystallinity and expansive layers in the mixed-layer IS determined advanced diagenesis for the unit, from late mesodiagenesis (Tonono x-1 and Vespucio x-1) to telodiagenesis (Balapuca and Ramos), according to the final stage of oil generation window to gas generation window, respectively. Finally, based on the mineral composition with a predominance of quartz (>70% in average) and low content of clays (100 km2), the unit has some of the attributes to be considered as a shale-type unconventional reservoir.Fil: Veizaga Saavedra, Juan Gonzalo. Universidad Nacional de Salta. Facultad de Ciencias Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Poiré, Daniel G.. Comision de Investigaciones Cientificas de la Provincia de Buenos Aires. Centro de Geologia Aplicada, Agua y Medio Ambiente.; ArgentinaFil: Vergani, Gustavo Dardo. No especifíca;Fil: Salfity, Jose Antonio. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Instituto del Cenozoico; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Rubinstein, Claudia Viviana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; ArgentinaFil: Pérez Leytón, Miguel A.. No especifíca

Vocalizaciones asociadas al comportamiento colonial de Cacicus chrysonotus leucoramphus (Icteridae) en Colombia

In order to assess the association between the vocalizations and the displayed behaviors of the Golden-shouldered Mountain Cacique (Cacicus chrysonotus leucoramphus), we sampled both acoustic and behavioral features at three sites in the Andes of Nariño, southern Colombia. We obtained seven vocalization types, six of them associated with at least one of the three identified behavioral categories (vigilance, alertness, and territorial defense), and one linked with a courtship exhibition. Vocalizations with higher values of bandwidth and frequency modulations were associated with territorial behavior, whereas those with lower values of bandwidth and few frequency modulations were associated with vigilance and alert. Results showed similarities in the acoustic structure of vocalizations and the related social context with other species as the C. cela and C. haemorrhous. C. c. leucoramphus uses specific types of vocalizations in a particular social context, with some vocalizations used in different behaviors. This study describes for the first time the social context in which vocalizations are associated with their behaviors.Con el objetivo de evaluar la asociación entre las vocalizaciones y los comportamientos del cacique montano norteño (Cacicus chrysonotus leucoramphus), se tomaron registros acústicos y conductuales de la especie en cuatro localidades de los Andes de Nariño, en el sur de Colombia. Se registraron seis tipos de vocalizaciones asociadas a por lo menos una de las tres categorías conductuales identificadas (vigilancia, alerta y defensa territorial), y una vocalización registrada en un único evento de cortejo. Vocalizaciones con valores más altos de ancho de banda y modulación de frecuencia resultaron asociadas a defensa territorial, mientras que vocalizaciones con valores bajos de ancho de banda y poca modulación cumplieron funciones de vigilancia y alerta. Los resultados indican similitudes en el comportamiento vocal y social con respecto a estudios en otras especies como Cacicus cela y Cacicus haemorrhous. C. c. leucoramphus utiliza vocalizaciones específicas en un determinado contexto conductual, pudiendo algunas de ellas ser reutilizadas en varios comportamientos. Este estudio describe por primera vez el contexto social en el que se asocian las vocalizaciones y conductas en esta especie