scholarly journals Stratigraphic forward modelling of distributive fluvial systems based on the Huesca System, Ebro Basin, Northern Spain

2021 ◽  
Author(s):  
Swiad Snieder ◽  
Cedric M. Griffiths ◽  
Amanda Owen ◽  
Adrian J. Hartley ◽  
John A. Howell
Keyword(s):  
Forward Modelling ◽  
Northern Spain ◽  
Ebro Basin ◽  
Fluvial Systems

scholarly journals Agricultural impacts on streams near Nitrate Vulnerable Zones: A case study in the Ebro basin, Northern Spain

PLoS ONE ◽  
2019 ◽  
Vol 14 (11) ◽  
pp. e0218582 ◽  
Author(s):  
Rubén Ladrera ◽  
Oscar Belmar ◽  
Rafael Tomás ◽  
Narcís Prat ◽  
Miguel Cañedo-Argüelles
Keyword(s):  
Northern Spain ◽  
Ebro Basin ◽  
Agricultural Impacts ◽  
Vulnerable Zones

scholarly journals Agricultural impacts on streams near Nitrate Vulnerable Zones: a case study in the Ebro basin, northern Spain

2019 ◽  
Author(s):  
Rubén Ladrera ◽  
Oscar Belmar ◽  
Rafael Tomás ◽  
Narcís Prat ◽  
Miguel Cañedo-Argüelles
Keyword(s):  
Riparian Forest ◽  
Agricultural Practices ◽  
Agricultural Activity ◽  
Northern Spain ◽  
Ebro Basin ◽  
Macroinvertebrate Assemblages ◽  
Management Actions ◽  
Wide Range ◽  
Nitrate Concentrations ◽  
Vulnerable Zones

AbstractAgricultural intensification during the last century has produced river degradation across Europe. From the wide range of pressures derived from agricultural activities that impact rivers, diffuse agricultural pollution has received most of the attention from managers and scientists. The aim of this study was to determine the main pressures exerted by intensive agriculture around Nitrate Vulnerable Zones (NVZs), which are areas of land that drain into waters polluted by nitrates according to the European Nitrate Directive (91/676/EEC). The study area was located in the NW of La Rioja (Northern Spain), which has the highest levels of nitrate concentrations within the Ebro basin. The relationships between forty environmental variables and the taxonomic and functional characteristics of macroinvertebrate assemblages (which are good indicators of water quality) were analyzed in 11 stream reaches differentially affected by upstream agricultural activity. The streams affected by a high percentage of agricultural area had significantly greater nitrate concentrations and distinct macroinvertebrate assemblages dominated by pollution tolerant taxa. Hydromorphological alteration (i.e. channel simplification, riparian forest degradation and sediment inputs), which is closely linked to agricultural practices, was the main factor affecting macroinvertebrate assemblages. Good agricultural practices should be implemented in streams affected by NVZs to reverse stream degradation, in consonance with the European Water Framework Directive (WFD). Management actions in these areas should not focus exclusively on nitrate reduction, but also on restoring riparian and aquatic habitats.

scholarly journals The freshwater and terrestrial turtles from Monte Pila and Fuenmayor (La Rioja, northern Spain): new data on the lower Miocene turtle diversity of the Ebro Basin

Geodiversitas ◽  
2021 ◽  
Vol 43 (3) ◽  
Author(s):  
Adán Pérez-García ◽  
Oier Suarez-Hernando ◽  
Jose M. Hernández ◽  
Salvador García ◽  
Xabier Murelaga
Keyword(s):  
Northern Spain ◽  
Ebro Basin ◽  
Lower Miocene ◽  
La Rioja

Paleohydraulic investigation of the Ebro Basin: Implications for Mars

2021 ◽  
Author(s):  
Heath Geil-Haggerty
Keyword(s):  
Water Discharge ◽  
Sedimentary Basins ◽  
Mass Conservation ◽  
Sediment Supply ◽  
Sediment Flux ◽  
River Channels ◽  
Ebro Basin ◽  
Fluvial Systems ◽  
Sediment Size ◽  
Basin Scale

<p>The stratigraphy preserved in Earth’s sedimentary basins offers a record of how landscapes have evolved with time.  This stratigraphy provides insights into the dynamic processes that shaped the surface of the earth.  Fluvial stratigraphy contains many elements that can be used to recreate past conditions in ancient river channels.  Paleohydraulic reconstruction uses measurements of fluvial stratigraphy to model the conditions in the system that created them.  This allows us to answer questions related to water discharge, sediment flux, and duration of fluvial activity.  These are key questions when investigated in the context of Mars.  Paleohydraulic models can be used as compelling analogs for similar systems on Earth as well as Mars and other rocky planets.           </p><p>This study examines what the record of Oligocene-Miocene fluvial stratigraphy in northeastern Spain’s Ebro Basin can tell us about water discharge and sediment flux across distributive fluvial systems at a basin scale.  The Cenozoic stratigraphy of northeastern Spain’s triangular shaped Ebro Basin embodies a classic example of the formation of a closed sedimentary basin.  The Ebro Basin contains a number of remarkably well exposed fluvial sedimentary deposits.  These deposits outcrop as distinctive laterally contiguous channel sand bodies.  Clastic sediment supply in the Ebro Basin is largely governed by tectonic uplift and basin subsidence related to the Pyrenean orogen with peripheral contributions from the Catalan Coast and Iberian Ranges.  We test the idea that the record of conditions in the fluvial systems should reflect the record of lacustrine chemical sediments through sediment mass conservation.  In order to test this hypothesis measurements of bedform height, barform height, sediment size, and paleochannel dimensions were collected in the field.  Our paleohydraulic model uses previously derived theoretical and empirical relationships to recreate the conditions in these ancient fluvial systems.  These results are scaled up by accounting for drainage density and intermittency in order to address the principal question at a basin scale.  Paleodischarges from the fluvial sediments are comparable to those from river chemistry calculations for the lacustrine facies. </p>

A palaeomagnetic analysis of Miocene fluvial sediments at Pertusa, near Huesca, Ebro Basin, Spain

1984 ◽  
Vol 121 (4) ◽  
pp. 279-290 ◽  
Author(s):  
P. Turner ◽  
J. P. P. Hirst ◽  
P. F. Friend
Keyword(s):  
Natural Remanent Magnetization ◽  
Northern Spain ◽  
Ebro Basin ◽  
Northern Margin ◽  
Fine Grained ◽  
Reducing Conditions ◽  
Secular Variations ◽  
Normal Polarity ◽  
Higher Temperature ◽  
Reversed Polarity

AbstractIn the Miocene fluvial system of the Huesca area, in the Ebro Basin, northern Spain, rivers radiated outwards, to the south and west, from a small sector of the northern margin of the basin. The deposits of the system extend about 60 km radially from this sector and then pass into calcareous and gypsiferous deposits.The magnetostratigraphy of two logged sections, 1 km apart, within this system consists of an upper zone of normal polarity and a lower zone of reversed polarity. The lithostratigraphy and magnetostratigraphy are parallel.The sands and silts are dominated by angular quartz, intraformational clay lithograins and calcite lithograins. They are mainly pale yellow brown to dusky yellow, and magnetic tests indicate that the magnetization is carried dominantly by ferric oxyhydroxides (haematite and gôethite). The higher temperature Natural Remanent Magnetization is probably due to detrital haematite which would have been partially aligned during fluvial deposition. Post-depositional modification (PDRM) may have occurred during dewatering.Haematite pseudomorphing pyrite framboids indicates that early reducing conditions were succeeded by a more oxidizing regime which produced secondary magnetizations associated with fine-grained haematite and goethite.Complete polarity zones are not delineated, but the thicknesses present are not excessive compared with other continental Miocene deposits. The average palaeolatitude of 22° is lower than would be expected for the Miocene of northern Spain, probably due to incomplete averaging of secular variations and other sources of error including possible ‘inclination error’.

Miocene point-bar deposits in the Ebro Basin, Northern Spain*

Sedimentology ◽  
1973 ◽  
Vol 20 (1) ◽  
pp. 133-144 ◽  
Author(s):  
CAYO PUIGDEFABREGAS
Keyword(s):  
Northern Spain ◽  
Ebro Basin ◽  
Point Bar
Sign in / Sign up

Export Citation Format

Share Document