Castro Urdiales Research Articles

New advances in the stratigraphy of Aptian oceanic anoxic events (Castro Urdiales, Basque-Cantabrian Basin, Spain)

The Aptian sedimentary deposits of the Castro Urdiales area in north Spain record an episode of disoxia/anoxia which postdates Oceanic Anoxic Event 1a (OAE 1a). Carbonate platform and overlying facies are analysed for stratigraphy, sedimentology, total organic carbon and carbon isotopes. Lower Aptian shallow-water limestones are covered by deeper-water marlstones and organic-carbon-rich black lutites of lower to upper Aptian, ranging from Dufrenoyia furcata Zone to Cheloniceras (Epicheloniceras) martinioides Zone. Biostratigraphy and chemostratigraphic calibration are based on ammonites, carbon isotopes and total organic carbon analyses, revealing consistency with the global Aptian reference framework. The Castro Urdiales black-shale levels of the lower to upper Aptian transition together with their encasing series are correlated with other Aptian sections of the Basque-Cantabrian Basin (northern Spain) and southeastern France. The Castro Urdiales black shales are correlated with the Aparein Level of the eastern Basque-Cantabrian Basin. Prior to this oxygen deficient episode, glauconite-and-ostreid facies were also deposited under oxic conditions during the Gutiolo volcanic event of the Basque-Cantabrian Basin. This volcanism correlates in part with the Cretaceous superplume eruptions of Ontong Java, Manihiki Plateaus and the North Atlantic opening as a result of increasing seafloor spreading rates.

The effects of astronomically forced climate change on hemipelagic carbonate sedimentation in a tectonically active setting: the Albian Mioño Formation in Castro Urdiales (Cantabria, N Spain)

Our understanding of the stratigraphic expression of astronomically driven climate-change cycles in the Milankovitch frequency band has improved significantly in recent decades. However, several aspects have been little studied to date, such as the nature of the climatically regulated environmental processes that ultimately control cyclic sedimentation. Similarly, relatively little is known about the expression of Milankovitch cycles in successions accumulated in tectonically active basins. In order to fill this knowledge gap, the Albian hemipelagic deposits of the Mioño Formation exposed in Castro Urdiales (Basque-Cantabrian Basin) are studied herein. These deposits were accumulated during a rifting phase with strong tectonic activity. The sedimentological, petrographic and cyclostratigraphic analysis demonstrates that, despite the synsedimentary tectonic instabilities and some diagenetic overprinting, the hemipelagic carbonate alternation was astronomically forced 110.68–110.47 Ma. Seasonality fluctuations driven by precession cycles caused periodic (20 ky) variations in the rate of carbonate productivity (abundance of pelagic calcareous plankton and micrite exported from adjacent shallow-water areas) and/or siliceous dilution (terrestrially derived siliciclastic sediment supply and siliceous particle production by sponges). These variations resulted in the formation of marly limestone beds when annual seasonality was low (i.e., boreal summer at aphelion, winter at perihelion) and the accumulation of marlstones when seasonality increased (i.e., boreal summer at perihelion, winter at aphelion). The incidence of these processes increased and decreased in line with seasonality modulation by short-eccentricity cycles of 100 ky. In conclusion, this study shows that Milankovitch cycles can be reliably recorded in hemipelagic successions accumulated in tectonically active settings if sediment gravity flows or other disturbances do not affect autochthonous sedimentation.

Morfología urbana, infraestructuras ferroviarias y crecimiento económico en las ciudades cántabras

En el territorio de la actual Comunidad Autónoma de Cantabria tuvo lugar desde mediados del siglo XVIII un intenso proceso de articulación territorial que culminó con la construcción del Ferrocarril de Isabel II y de la red ferroviaria de vía estrecha. Las nuevas infraestructuras viarias favorecieron el crecimiento de algunos núcleos urbanos entre los que se encuentran Castro Urdiales, Torrelavega y, sobre todo, la capital regional, Santander. Aunque con distinta intensidad, tiempos y ritmos, representan tres notables ejemplos del proceso de transición urbana y urbanística en España.El núcleo central de la investigación en que se apoya este artículo es el impacto urbanístico diferencial de las infraestructuras ferroviarias en la remodelación de la morfología urbana y en el nacimiento de nuevos paisajes urbanos.En Santander influyeron en la potenciación del centro urbano y de la “ciudad balnearia” de El Sardinero, así como en la configuración de áreas suburbanas y periurbanas industriales, que constituyeron unidades paisajísticas bien diferenciadas. En Torrelavega las dos estaciones existentes funcionaron de manera muy distinta en la articulación del espacio y el paisaje urbano. Los ferrocarriles mineros de Castro Urdiales constituyeron un verdadero “cinturón de hierro” mientras que, por el contrario, la localización periférica de la estación tuvo escaso impacto.

Los procesos de metropolitanización dispersa: Castro Urdiales (Cantabria) en la región urbana de Bilbao

Castro Urdiales (Cantabria) es un ejemplo paradigmático de la problemática de los actuales procesos de urbanización, del crecimiento de los pequeños núcleos periféricos de una aglomeración urbana a partir de la descentralización y dispersión intrametropolitana, del cambio morfológico de los espacios urbanos a consecuencia del "estallido" de la ciudad y la diseminación de fragmentos construidos de la misma por las áreas rurales más o menos próximas. No obstante, también presenta algunas singularidades provenientes, sobre todo, de su pertenencia político-administrativa a una Comunidad Autónoma distinta de aquélla en la que se encuentra el núcleo central y las demás entidades integrantes de la región urbana, el País Vasco. Los límites autonómicos no parecen haber sido un obstáculo para la configuración funcional del área metropolitana más allá de los confines que deslindan el territorio político-administrativo, pero sí producen "efectos de frontera” como consecuencia de las actuaciones de las administraciones implicadas, locales y autonómicas, en materia urbanística y de dotación de infraestructuras, servicios y equipamientos.

Los usos políticos del espacio público en algunas villas del norte de castilla. siglos XV y XVI

A partir de documentación municipal del valle de Valderredible, de la villa de Castro Urdiales y de la de Segura, se busca analizar las manifestaciones políticas y discursivas del común urbano. Así, los circuitos de la comunicación política son estudiados en base a su relación conexa con los lugares físicos y públicos en los que se generaba y por los que circulaba. En un contexto histórico marcado por la exclusión política del común de los resortes formales del gobierno urbano, y el fortalecimiento de los grupos señoriales; detectar el punto justo en el que lo rumoreado se convertía en noticia política, contribuye a la comprensión de las lógicas del poder político en la modernidad temprana. El objetivo final consiste en discutir la significativa correlación que existía entre el bien común como ideal a perseguir y el espacio público como construcción social.

Reivindicación de estatus y costumbres foráneas en el registro funerario medieval castellano. A propósito de dos casos de Cantabria

Description and interpretation of two funerary contexts from 12th-13th Centuries Cantabria: the burials with «golden spurs» in San Martin de Elines and the grave with incense pots in Santa Maria de la Ascension of Castro Urdiales. The first case connects with the development of noble cavalry in Castile in 13th Century, whereas in the second one the reasons for the presence of a funerary custom unconnected with the local tradition are analysed.

Estimation of PM10-Bound As, Cd, Ni and Pb Levels by Means of Statistical Modelling: PLSR and ANN Approaches

Air quality assessment regarding metals and metalloids using experimental measurements is expensive and time consuming due to the cost and time required for the analytical determination of the levels of these pollutants. According to the European Union (EU) Air Quality Framework Directive (Directive 2008/50/EC), other alternatives, such as objective estimation techniques, can be considered for ambient air quality assessment in zones and agglomerations where the level of pollutants is below a certain concentration value known as the lower assessment threshold. These conditions occur in urban areas in Cantabria (northern Spain). This work aims to estimate the levels of As, Cd, Ni and Pb in airborne PM10 at two urban sites in the Cantabria region (Castro Urdiales and Reinosa) using statistical models as objective estimation techniques. These models were developed based on three different approaches: partial least squares regression (PLSR), artificial neural networks (ANNs) and an alternative approach consisting of principal component analysis (PCA) coupled with ANNs (PCA-ANN). Additionally, these models were externally validated using previously unseen data. The results show that the models developed in this work based on PLSR and ANNs fulfil the EU uncertainty requirements for objective estimation techniques and provide an acceptable estimation of the mean values. As a consequence, they could be considered as an alternative to experimental measurements for air quality assessment regarding the aforementioned pollutants in the study areas while saving time and resources.

Estructura y forma de la ciudad a través de la cartografía histórica: Castro Urdiales, Cantabria (1800-1960)

El presente artículo se plantea como objetivo el análisis de la evolución estructural y morfológica de un espacio urbano de rango y tamaño modestos, Castro Urdiales (Cantabria), desde su condición histórica de villa marinera hasta su consolidación como ciudad industrial moderna. Desde una perspectiva metodológica, la parte más substancial del análisis de la dinámica urbanística se apoya esencialmente en el uso de las imágenes cartográficas, como referencias documentales que proporcionan datos y testimonios que no se encuentran en otras fuentes. No obstante, como sucede con otras fuentes documentales, la información obtenida de mapas y planos ha sido combinada y complementada con otro tipo de fuentes coetáneas a las cartográficas. Y, por descontado, se han adoptado las oportunas precauciones, similares a las tomadas con las fuentes escritas, sobre posibles errores de información mediante el contraste y la comparación de unas y otras fuentes, cartográficas y literarias.

La aportación de Castro Urdiales a la Armada Invencible (1586-1618)

Durante al menos 30 anos los herederos de los vecinos de Castro Urdiales que habian participado en la Jornada de Inglaterra de 1588 o los propios supervivientes estuvieron reclamando a la Corona el pago de sus salarios como marineros, artilleros o pilotos; gracias a los poderes otorgados por los interesados, donde hicieron constar las peripecias de los castrenos en aquella triste ocasion, es posible reconstruir la participacion de la villa cantabra en esa y otras armadas de la epoca.

Pottery Manufacturing during the Neolithic in the North of Spain: Raw Material Procurement and Modification in the Cave of Los Gitanos (Castro Urdiales, Spain)

Mineralogical and geochemical results derived from analyses of the pottery ensemble documented in the Cave of Los Gitanos (Castro Urdiales, Spain) are presented in this paper. This site contains an archaeological deposit formed in the mid‐fifth millennium cal bc, which has yielded one of the oldest pottery assemblages in northern Spain. The analysis of the pottery remains has focused on both petrographic (thin‐section and XRD) and geochemical characterization (SEM–EDS) of samples selected after a macroscopic study. The mineralogical analysis has revealed procurement of raw materials from different sources, as well as different manufacturing processes. In addition, the petrographic analysis has shown different methods of manufacture, such as pottery tempered with calcite, limestone, ophite (ophitic dolerite) and grog, and fabrics with non‐modified clays. Variations observed between the oldest assemblage (Sub‐levels A4 and A3) and the most recent one (Sub‐level A2) suggest a modification in pottery‐making practices between the fifth and the third millennia cal bc.

Evaluation of the urban/rural particle-bound PAH and PCB levels in the northern Spain (Cantabria region)

The aim of the present study was to evaluate the polycyclic aromatic hydrocarbon (PAH) and polychlorinated biphenyl (PCB) levels in PM(10) and PM(2.5), at one rural and three urban sites in the Cantabria region (northern Spain). From all of these pollutants, benzo(a)pyrene is regulated by the EU air quality directives; its target value (1 ng/m(3)) was not exceeded. The concentration values of the studied organic pollutants at the studied sites are in the range of those obtained at other European sites. A comparison between the rural-urban stations was developed: (a) PAH concentration values were lower in the rural site (except for fluorene). Therefore, the contribution of local sources to the urban levels of PAHs seems relevant. Results from the coefficient of divergence show that the urban PAH levels are influenced by different local emission sources. (b) PCB rural concentration values were higher than those found at urban sites. Because no local sources of PCBs were identified in the rural site, the contribution of more distant emission sources (about 40 km) to the PCB levels is considered to be the most important; the long-range transport of PCBs does not seem to be significant. Additionally, local PAH tracers were identified by a triangular diagram: higher molecular weight PAHs in Reinosa, naphthalene in Santander and anthracene/pyrene in Castro Urdiales. A preliminary PAH source apportionment study in the urban sites was conducted by means of diagnostic ratios. The ratios are similar to those reported in areas affected by traffic emissions; they also suggest an industrial emission source at Reinosa.

Regional evaluation of particulate matter composition in an Atlantic coastal area (Cantabria region, northern Spain): Spatial variations in different urban and rural environments

The aim of this study was to determine the major components (Na, Ca, K, Mg, Fe, Al, NH 4 +, SO 4 2−, NO 3 −, Cl − and TC) and trace-metal levels (As, Ni, Cd, Pb, Ti, V, Cr, Mn, Cu, Mo, Rh and Hg) in PM 10 and PM 2.5 at an Atlantic coastal city (Santander, Cantabria region, Northern Spain). Additional samples were collected in other urban sites of the Cantabria region to assess the metal content found in different urban environments within the region. To control for the mass attributed to inland regional background particulate matter, samples were also collected in Los Tojos village. The spatial variability of the major PM components shows that PM origins are different at inland and coastal sites. In the coastal city of Santander, the most important contributors are (i) the marine aerosol and (ii) the secondary inorganic aerosol (SIA) and the total carbon (TC) in PM 10 and PM 2.5, respectively. Additionally, the influence of the coastal location on the ionic balance of PM is also studied. The trace metal spatial variability is studied using the coefficient of divergence (COD), which shows that the levels of trace metals at the three studied urban sites are mainly influenced by local emission sources. The main local tracers are identified as follows: Mn in the Santander area; Mo, Cr and Pb at Reinosa; and Ni and V at Castro Urdiales. A more detailed source apportionment study of the local trace metals at Santander is conducted by Principal Component Analysis (PCA) and Positive Matrix Factorisation (PMF); these two receptor models report complementary information. From these statistical analyses, the identified sources of trace metals in PM 10 are urban background sources, industrial sources and traffic. The industrial factor was dominated by Mn, Cu and Pb, which are trace metals used in steel production and manganese-ferroalloy production plant. With respect to PM 2.5, the identified emission sources of trace metals are combustion processes as well as traffic and industrial sources.

<i>Preface</i> "Nonlinear processes in oceanic and atmospheric flows"

Abstract. Nonlinear phenomena are essential ingredients in many oceanic and atmospheric processes, and successful understanding of them benefits from multidisciplinary collaboration between oceanographers, meteorologists, physicists and mathematicians. The present Special Issue on "Nonlinear Processes in Oceanic and Atmospheric Flows" contains selected contributions from attendants to the workshop which, in the above spirit, was held in Castro Urdiales, Spain, in July 2008. Here we summarize the Special Issue contributions, which include papers on the characterization of ocean transport in the Lagrangian and in the Eulerian frameworks, generation and variability of jets and waves, interactions of fluid flow with plankton dynamics or heavy drops, scaling in meteorological fields, and statistical properties of El Niño Southern Oscillation.

POLAR INVARIANTS OF PLANE CURVE SINGULARITIES: INTERSECTION THEORETICAL APPROACH

This article, based on the talk given by one of the authors at the Pierret- tefest in Castro Urdiales in June 2008, is an overview of a number of recent results on the polar invariants of plane curve singularities.

Polar invariants of plane curve singularities: intersection theoretical approach

AbstractThis article, based on the talk given by one of the authors at the Pierrettefest in Castro Urdiales in June 2008, is an overview of a number of recent results on the polar invariants of plane curve singularities.

Relative importance of protozoan functional groups in three marine sublittoral areas

The composition in terms of protozoan functional groups of three sublittoral areas (Castro Urdiales, Santoña and Isla) in the Cantabrian Sea was analysed. The different protozoan species were identified, and their density and biomass was measured. The pigmented protozoa were the most important group in the three areas throughout the year, followed by the bacterivores in Castro Urdiales and Santoña, and the non-selectives in Isla. Bacterivores constituted the most significant group in terms of biomass, after which came that of non-selectives. The parameters with the strongest influence on distribution in functional groups (respect to biomass) were pH, phosphate, organic matter and bacterial biomass, other significant factors being salinity, nitrate and mean grain size. Functional groups expressed as number of species were affected principally by phosphate, pH and, to a lesser extent, temperature and salinity. Statistical analysis using the present data, data regarding functional groups from previous studies in the same areas, and data from other areas, indicate that marine areas show similar characteristics. In the areas covered by the present study, there was a decrease in the number of algivore species and a rise in non-selective species, while bacterivores and pigmented protozoa maintained similar values. In comparison, freshwater areas showed noticeably lower percentages of algivore species and a significantly higher number of bacterivore species.

Controls on carbonate-platform evolution on active fault blocks; the Lower Cretaceous Castro Urdiales Platform (Aptian-Albian, northern Spain)

ABSTRACT Four contrasting carbonate sequences developed in a tectonically active, extensional setting in the Lower Cretaceous (Aptian-Albian) Castro Urdiales platform of north Spain. The four carbonate phases (P1-P4; early Aptian, late Aptian, earliest Albian, and early-late Albian, respectively) are identified across the platform-to-basin transition on the basis of sedimentary geometries and internal facies patterns. They are vertically separated by four incipient drowning events (D1-D4; middle Aptian, Aptian-Albian boundary, early Albian, and late Albian). The first carbonate stage (P1) corresponds to a low-relief carbonate platform characterized by widespread shallow-marine depositional environments with a nearly flat organization. The second platform stage (P2) developed as a rimmed carbonate platform. The third carbonate stage (P3) evolved from a low-relief aggradational platform (substage A) to a progradational offlapping platform (substage B), and back to a backstepped, aggradational rimmed platform (substage C), responding to changes in differential subsidence and carbonate production. At the beginning of the Albian the Castro Urdiales carbonate platform was broken up by extensional tectonic movements with formation of fault blocks bounded by NE-SW and NW-SE trending faults. On the crests of uplifted blocks meteoric processes were active, whereas grabens and half grabens acted as channel conduits for terrigenous-rich deposits. Subsidence rates increased during the late early Albian-late Albian. The crests of rotated blocks formed paleohighs that nucleated small residual carbonate platforms (carbonate stage P4) that were surrounded by deeper-water basins. This study suggests that the evolution of carbonate platform sequences in the Lower Cretaceous of Castro Urdiales was primarily controlled by changes in accommodation space, which were most likely driven by intraplate stresses related to extension in the north Spanish continental margin during the opening of the North Atlantic. Drowning events in the Castro Urdiales platform coincide with major crises of Cretaceous carbonate production worldwide, suggesting that regional tectonism and global oceanic changes interacted to cause phases of platform demise.

Controls on Carbonate-Platform Evolution on Active Fault Blocks: The Lower Cretaceous Castro Urdiales Platform (Aptian-Albian, Northern Spain)

Controls on Carbonate-Platform Evolution on Active Fault Blocks: The Lower Cretaceous Castro Urdiales Platform (Aptian-Albian, Northern Spain)

Lucerna romana de bronce procedente de Castro Urdiales (Cantabria)

This article is intended to present a Roman lamp of bronze, which was obtained from a rescue excavation in Castro Urdiales (Cantabria). This piece can be identified with the type known as Loeschcke XX, very well represented in the sites of Pompeii and Herculaneum , dated to the second half of the first century and the beginning of the second century AD. It was widespread through the different provinces of the Empire. The piece under study appeared in an archaeological context that has been related to the colonia Flaviobriga; the latter is mentioned by the classic sources.

Carbonate depositional sequence development on active fault blocks: the Albian in the Castro Urdiales area, northern Spain

ABSTRACTThe Aptian to lowermost Albian carbonate platform of Castro Urdiales (Cantabria, northern Spain) was broken up by extensional tectonic movements shortly after the beginning of the Albian. Block faulting characterized this rifting episode, the effects of which waned during the Albian. In crestal locations tilting of the fault blocks caused the subaerial exposure of parts of the older platform, resulting in intense karst diagenesis. Differential subsidence of the blocks controlled the development of a crestal residual carbonate platform (Arenillas), which was surrounded by deeper water on both sides. Seven unconformities related to platform exposure and karstification are identified on the Arenillas platform, and form the basal boundaries of seven depositional sequences (S1‐S7). On the platform, lowstand systems tract deposits consist of breccias filling caves, and grainstones and debris flow deposits filling incised canyons. Transgressive plus highstand systems tracts consist of rare marls plus shallow water rudistid, coral and chondrodontid limestones. In the basin, the unconformities are erosional surfaces at the base of resedimented limestones, marls or sandy or silty siliciclastics (lowstand systems tracts). Transgressive plus highstand systems tracts in this setting consist of marls and hemipelagic marly limestones. Tectonism is believed to be the main control on sequence formation, and only a few sequence boundaries (e.g. the base of S6 in the Upper Albian inflatum Zone) can be correlated with eustatic events.