000161694 001__ 161694
000161694 005__ 20251017144601.0
000161694 0247_ $$2doi$$a10.1344/GeologicaActa2025.23.10
000161694 0248_ $$2sideral$$a144365
000161694 037__ $$aART-2025-144365
000161694 041__ $$aeng
000161694 100__ $$aLarena, Zuriñe
000161694 245__ $$aQuaternary tufas of the Inglares River valley: An example of changing slope stepped fluvial system, Álava, N Spain
000161694 260__ $$c2025
000161694 5060_ $$aAccess copy available to the general public$$fUnrestricted
000161694 5203_ $$aThis study examines the factors that controlled the formation of Quaternary calcareous tufa deposits along the valley of the Inglares River (Álava, north Spain), currently fed by a karst-carbonate aquifer. It is based on stratigraphic, chronological (Amino Acid Racemisation, AAR), sedimentological, and δ13C and δ18O analyses, complemented by palaeontology (molluscs, ostracods and charophytes). The examined deposits occur as isolated bodies in the uppermost and downmost stretches of the valley, reaching 45 and 25m in thickness, respectively. AAR dating classified them into two groups: Middle Late Pleistocene (MIS 5e) and Middle and Late Holocene (MIS 1). The former only occurred in the downstream stretch. Up to eleven carbonate facies and minor allochthonous coarse detrital facies have been characterised and arranged into four distinct facies associations. Their features and bedding geometries suggested two main depositional settings: a low- to moderate-slope stepped stretch with small barrage cascades, dammed areas, and abundant palustrine zones (downstream system) and a high-slope stretch with steep stepped cascades and pools (upstream system). These settings respond to bedrock lithology and structural changes throughout the valley, which appear to be the principal factors controlling the tufa depositional architecture. Based on δ13C, an increase in aridity was inferred from the Middle–Late Pleistocene to Holocene. The isotopic differences between the upstream and downstream Holocene tufa might reflect the spatial evolution of δ13C and δ18O in stream water through the approximately 8km long surveyed transect. Erosion due to sudden changes in water discharge may have caused the stratigraphic gap between the two tufa groups.
000161694 536__ $$9info:eu-repo/grantAgreement/ES/DGA/E32-23R
000161694 540__ $$9info:eu-repo/semantics/openAccess$$aby-sa$$uhttps://creativecommons.org/licenses/by-sa/4.0/deed.es
000161694 655_4 $$ainfo:eu-repo/semantics/article$$vinfo:eu-repo/semantics/publishedVersion
000161694 700__ $$0(orcid)0000-0002-4212-0524$$aArenas, Concha$$uUniversidad de Zaragoza
000161694 700__ $$aOrtiz, José Eugenio
000161694 700__ $$aSanjuan, Josep
000161694 700__ $$aPascual, Ana
000161694 700__ $$aLarraz, Mariano
000161694 700__ $$aMurelaga, Xabier
000161694 700__ $$aBaceta, Juan Ignacio
000161694 7102_ $$12000$$2280$$aUniversidad de Zaragoza$$bDpto. Ciencias de la Tierra$$cÁrea Estratigrafía
000161694 773__ $$g23 (2025), 1-32$$pGeol. acta$$tGeologica Acta$$x1695-6133
000161694 8564_ $$s17120495$$uhttps://zaguan.unizar.es/record/161694/files/texto_completo.pdf$$yVersión publicada
000161694 8564_ $$s2443528$$uhttps://zaguan.unizar.es/record/161694/files/texto_completo.jpg?subformat=icon$$xicon$$yVersión publicada
000161694 909CO $$ooai:zaguan.unizar.es:161694$$particulos$$pdriver
000161694 951__ $$a2025-10-17-14:14:11
000161694 980__ $$aARTICLE