Quaternary tufas of the Inglares River valley
This work discusses the factors that controlled the formation of Quaternary tufa deposits along the valley of Inglares River, currently fed by a karst-carbonate aquifer, Álava, north Spain. It is based on stratigraphic, chronological (amino-acid racemization, AAR), sedimentological and d13C and d18O...
| Autores: | , , , , , , , |
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| Tipo de documento: | artigo |
| Data de publicação: | 2025 |
| País: | España |
| Recursos: | Universitat Autònoma de Barcelona |
| Repositório: | Dipòsit Digital de Documents de la UAB |
| Idioma: | inglês |
| OAI Identifier: | oai:ddd.uab.cat:312243 |
| Acesso em linha: | https://ddd.uab.cat/record/312243 https://dx.doi.org/urn:doi:10.1344/GeologicaActa2025.23.10 |
| Access Level: | Acceso aberto |
| Palavra-chave: | Fluvial tufa Sedimentology Facies model Quaternary climate North iberia |
| Resumo: | This work discusses the factors that controlled the formation of Quaternary tufa deposits along the valley of Inglares River, currently fed by a karst-carbonate aquifer, Álava, north Spain. It is based on stratigraphic, chronological (amino-acid racemization, AAR), sedimentological and d13C and d18O analyses, complemented with paleontology. The examined deposits occur as isolated bodies at the uppermost and downmost stretches of the present valley, reaching 45 and 25 m thick, respectively. AAR dating set them in two groups: Middle-Late Pleistocene (MIS 5e) and Middle and Late Holocene (MIS 1). The former only occurs in the downstream stretch. Up to eleven carbonate facies and minor allocththonous coarse-detrital facies have been characterised and arranged into four distinct facies associations. Their features and bedding geometry suggest two main depositional settings. A low- to slightly moderate-slope, stepped stretch with small barrage-cascades, dammed areas, and abundant palustrine facies (downstream system and a high-slope stretch with steep stepped cascades and pools (upstream system). These settings respond to bedrock lithology and structure changes through the valley, which appear to be principal factors controlling the tufa depositional architecture. Based on d13C, an increase in aridity in inferred from the Middle-Late Pleistocene to the Holocene. The isotopic differences between the upstream and downstrem Holocene tufa might reflect the spatial evolution of d13C and d18O of stream water through the ca 8-km long surveyed transect. Erosion by sudden changes in water discharge might have caused the stratigraphic gap between the two tufa groups. |
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