Caracterización de facies, lito estratigrafía y ambientes de depositación que diferencian la secuencia sedimentaria aflorante en la vía que conduce a las veredas Tampanqueba y Cúnuba del municipio de Pamplona, Norte de Santander – Colombia

Abstract

To the southeast of the Department of Norte de Santander in the rural area of the municipality of Pamplona, on the road that leads to the villages Tampanqueba and Cúnuba sedimentary rocks of the Lower Aptian-Albian Cretaceous corresponding to the Basin of the Catatumbo which are in discordant contact with metamorphic low grade rocks corresponding to the metamorphosed Floresta Formation. These sedimentary rocks show differences in their depositional environments. For the realization of this project of investigative modality, a photointerpretation was carried out in which aerial photographs were used, being able to determine different drainage patterns, accessroads, and the geomorphology of the area. The cartographic survey of 6 Km2 was carried out at a scale of 1: 10,000 in which 31 samples were taken at the different stations, describing all of their most relevant characteristics; followed by this, the stratigraphic survey was carried out using a 180-meter scale method at a scale of 1: 100, where 84 in situ rock samples were taken, of which 7 thin sections were made, 35 rock pellets for the determination of micro facies of each of them and by comparative method the identification of fossils. The stratigraphic section begins with a lithological discordance between green phyllites corresponding to the Floresta Formation Metamorphosed with the Conglomerate Member La Leonor of the Tibú Formation, to these conglomerates it is emphasized by the limestone member Cúnuba that is formed by medium layers of quartzite, gray limestones fossils that vary from Mudstone to Grainstone, calcareous sandstones and siltstones; at the top of this formation is the Member Sandstones and Limestones of La Recta conformed by gray limestones that grade from Mudstone to Packstone with calcareous sandstones and siltstones corresponding to the Tibú Formation; in contact is the Mercedes Formation formed by the members: Limestones Vereda Santa Member, Member limolitas and limestones Tampaqueba and Member Limolitas, Sandstones and Limestones El Tope; the Limestone Side Member Santa Ana is identified by layers of gray limestone that go from Mudstone to Grainstone, towards the intermediate part is located the Limolite limestone member and Tampaqueba with an intercalation of gray limestones that vary Mudstone to Grainstone with siltstones and calcareous mudstones followed by Member Limolites, Sandstones and Limestones The Tope where gray limestones are found that vary from Mudstone to Packstone interspersed with limolites and calcareous mudstone, ending the sequence with sub-arc-shaped sandstones with the presence of Muscovite and glauconite. From the above it can be determined by means of facial changes, the different depositional environments that vary from deltaic fluvial to continental shelf that oscillates between the 50 to 200 meters of depth corresponding to the first transgression of the Cretaceous.