Climatic and tectonic significance of Late Pleistocene and Holocene tufa deposits in the Mijares River canyon, eastern Iberian Range, northeast Spain

Abstract

The tufa deposits developed in the Mijares River canyon at the eastern sector of the Iberian Range were studied by using geomorphological, stratigraphic, micromorphological, mineralogical and chronological (U/Th and 14 C) techniques. These tufas are located along a high-gradient river profile reach, with high water turbulence and mechanical outgassing, related to Quaternary faulting activity upstream in the regional context of an extensional tectonic regime. Two stepped and terraced fluviatile tufa structures with large phytohermal barrage frameworks and smaller dammed areas have been differentiated. The first structure, Upper Pleistocene in age (from 200 000 to 50 000 years BP), is made up by two morphosedimentary units reaching 120 m in thickness, and the second one, Holocene in age (10 000-5000 years BP), is 35 m in thickness. These structures record a more or less continuous tufa development with a mean deposition rate ranging between 1 and 5 mm a À1 as minimum. A preferential growth with high biological activity during warm and wet palaeoenvironmental stages (isotopic stages 7, 3 and 1) can be deduced. Thus, neotectonic activity controlled the location along the Mijares River as well as the large thickness of the tufa deposits, whereas warm climatic periods favoured intense tufa activity in the fluvial system.

Tufa and Travertine

“…For example, Drysdale and Gillieson (1997) found a mean deposition rate of 4.15 mm yr −1 along Louie Creek, Queensland, Australia, and Merz-Preiss and Riding (1999) found rates of up to 2.2 mm yr −1 on tufa barrages in small freshwater streams in southern Germany. Longer-term estimates of deposition rates, from Pleistocene and Holocene barrage tufas in the Mijares River canyon, Spain, give similar rates of 1-5 mm yr −1 (Pena et al, 2000). At the famous Plitvice Lake barrages, accumulation rates of 1-3 cm yr −1 have been observed, with downstream barrages showing the fastest rates (Chafetz et al, 1994).…”

El sistema de barreras tobáceas holocenas de Las Parras de Martín (Cordillera Ibérica, Teruel)

“…En estos puntos se produce un incremento súbito de la turbulencia y agitación del agua, que conducen a su desgasificación mecánica (pérdi-da de CO 2 disuelto), favoreciendo la precipitación del carbonato. En general, existe una estrecha correspondencia entre discontinuidades morfotopográficas y formación de tobas en los sistemas tobáceos fluviales (Meléndez et al, 1996;Sancho et al, 1997;Peña et al, 2000;Arenas et al, 2004Arenas et al, , 2010aLozano et al, 2012;Vázquez-Urbez et al, 2011a,b, 2012.…”

“…Desde un punto de vista regional, durante el Holoceno se registra una fase de elevada actividad tobácea a escala mediterránea en los diferentes sistemas fluviales que drenan la Cordillera Ibérica hacia las cuencas de los ríos Ebro (Martínez-Tudela et al, 1986;Arenas et al, 2004Arenas et al, , 2010aValero-Garcés et al, 2008a;Vázquez-Urbez et al, 2011a), Tajo (Ordoñez et al, 1987, 1990Torres et al, 2005;Valero-Garcés et al, 2008b;Ortiz et al, 2009;Domínguez-Villar et al, 2011) y cuencas mediterráneas (Sancho et al, 1997;Peña et al, 2000;Lozano et al, 2012).…”

Factors controlling present-day tufa dynamics in the Monasterio de Piedra Natural Park (Iberian Range, Spain): depositional environmental settings, sedimentation rates and hydrochemistry

“…Some of these give estimates of sedimentation rates based on the time span and total thickness. In NE Spain, Peña et al (2000) provided a minimum of 0.8 mm/year for the Middle-Upper Pleistocene, and 4-5 mm/year for the Holocene. In central Spain, Andrews et al (2000) calculated Holocene rates of 1.2-2.4 mm/year from cored lacustrine tufas and 2.4 mm/year for pool tufas.…”