181 research outputs found
DESCRIPCIÓN DE UNA NUEVA UNIDAD DE LAVAS DENOMINADA ANDESITAS BASÁLTICAS DE EL MORITO - CORRELACIÓN REGIONAL CON EVENTOS MAGMÁTICOS DE ARCO
No full textLa unidad Andesitas basálticas de El Morito aflora en la zona de convergencia del basamento oceánico de la Cordillera Occidental y el basamento continental de la Cordillera Central, junto a la Formación Combia; está constituida por basaltos y andesitas basálticas con textura porfirítica, tiene fenocristales de plagioclasa y clinopiroxeno principalmente y ocasionalmente olivino y ortopiroxeno que flotan en una matriz microcristalina con textura fluidal a pilotaxítica; corresponden a lavas de series shoshoníticas con valores más altos en K2O, Na2O, P2O5 y valores mayores en los elementos de tierras raras livianas Rb, Ba, Th, U, K, La, Ce, Pr, Sr, P, Nd, Zr, Sm y Eu y menores en Ti, Y, Yb y Dy, que las lavas calcoalcalinas de la Formación Combia. La edad de las unidades del Arco de El Botón de afinidad shoshonítica corresponden al rango entre 9 y 12,5 Ma incluyendo las Andesitas basálticas de El Morito, mientras las edades de unidades que hacen parte de la Formación Combia están en el rango de 6 a 8,5 Ma.El Morito basaltic Andesite unit outcrops in the converging zone of the oceanic basement of the western cordillera and the continental basement of the central mountain range, beside the Combia Formation. It is formed by basalt and basaltic andesite with porphyritic texture, it has phenocrysts of plagioclase and clinopyroxene mainly, and occasionally olivine and orthopyroxene that float on a microcrystalline matrix with a fluidal texture to phyllotaxis; they correspond to shoshonitic magma series with highest values in K2O, Na2O, P2O5 and major values in the elements Rb, Ba, Th, U, K, La, Ce, Pr, Sr, P, Nd, Zr, Sm and Eu and minor values in Ti, Y, Yb y Dy, than the calc-alkaline magmas of the Combia Formation. The age of the units of the Arco de El Botón which has shoshonitic affinity, corresponds to a range between 9 and 12.5 Ma, including the basaltic andesite of El Morito, while the ages of the units belonging to the Combia Formation are located in the range from 6 to 8.5 Ma
DESCRIPTION OF A NEW LAVA UNIT NAMED EL MORITO BASALTIC ANDESITE - REGIONAL CORRELATION WITH ARCH MAGMATIC EVENTS.
No full textEl Morito basaltic Andesite unit outcrops in the converging zone of the oceanic basement of the western cordillera and the continental basement of the central mountain range, beside the Combia Formation. It is formed by basalt and basaltic andesite with porphyritic texture, it has phenocrysts of plagioclase and clinopyroxene mainly, and occasionally olivine and orthopyroxene that float on a microcrystalline matrix with a fluidal texture to phyllotaxis; they correspond to shoshonitic magma series with highest values in K2O, Na2O, P2O5 and major values in the elements Rb, Ba, Th, U, K, La, Ce, Pr, Sr, P, Nd, Zr, Sm and Eu and minor values in Ti, Y, Yb y Dy, than the calc-alkaline magmas of the Combia Formation. The age of the units of the Arco de El Botón which has shoshonitic affinity, corresponds to a range between 9 and 12.5 Ma, including the basaltic andesite of El Morito, while the ages of the units belonging to the Combia Formation are located in the range from 6 to 8.5 Ma.La unidad Andesitas basálticas de El Morito aflora en la zona de convergencia del basamento oceánico de la Cordillera Occidental y el basamento continental de la Cordillera Central, junto a la Formación Combia; está constituida por basaltos y andesitas basálticas con textura porfirítica, tiene fenocristales de plagioclasa y clinopiroxeno principalmente y ocasionalmente olivino y ortopiroxeno que flotan en una matriz microcristalina con textura fluidal a pilotaxítica; corresponden a lavas de series shoshoníticas con valores más altos en K2O, Na2O, P2O5 y valores mayores en los elementos de tierras raras livianas Rb, Ba, Th, U, K, La, Ce, Pr, Sr, P, Nd, Zr, Sm y Eu y menores en Ti, Y, Yb y Dy, que las lavas calcoalcalinas de la Formación Combia. La edad de las unidades del Arco de El Botón de afinidad shoshonítica corresponden al rango entre 9 y 12,5 Ma incluyendo las Andesitas basálticas de El Morito, mientras las edades de unidades que hacen parte de la Formación Combia están en el rango de 6 a 8,5 Ma
Flow in Fractured Media: a Darcy-Stokes-Brinkman Modelling Approach
No full textCoupling between porous media and free flow is widely present in many applications. In fractured reservoirs, fractures are often treated as parallel (smooth) plates, between which the flow is assumed to be steady state fully developed, with no-slip boundary condition. Under these assumptions, the Darcy law is employed inside fractures with permeability (Kf ) as a quadratic function of aperture (a), i.e., Kf = a2/12. Although this model is a rough simplification of real rock fractures, it is still widely used in subsurface flowmodelling. This study aims to investigate the validity range of the so-called local cubic law (LCL) by using a Darcy-Stokes-Brinkman model in which a unified formulation describes the Stokes flow in the free-flow sub-domain and Darcy flow in the porous sub-domain. Two simulation strategies are developed: a sequentially coupled approach, and a fully coupled approach. The nonlinear velocity profiles inside the free flow require enough grid resolution to be captured. As such, the grid resolution sensitivity is presented. More importantly, the permeability contrast between the two media is found to be an important factor for the applicability of the LCL (Darcy-Darcy) approach. A threshold of 10−7 is found, below which the difference between the two modelling approaches is negligible, and above which the LCL model no longer provide reasonable results
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