Another view of geological heritage: the assessment of the quaternary deposits of the galician coast (NW Spain)

En la última década se ha desarrollado una base de conocimiento sólido relacionado con la geodiversidad, caracterización, conservación y gestión del patrimonio geológico, que lleva implícito una legislación al respecto. Sin embargo, el escaso conocimiento a nivel científico por parte de la Administración sobre “lugares de interés geológico” hace complicado conseguir una normativa adecuada, a fin de proteger algo que no está contemplado. A esto se suma, un desconocimiento parcial de la sociedad sobre procesos geológicos, su relación con la biodiversidad y su valor como patrimonio natural. Este trabajo tiene como objetivo mostrar el valor de los depósitos sedimentarios antiguos localizados en la costa de Galicia como archivos paleoambientales y geoformas con entidad propia. Estos valores son ejemplificados con depósitos localizados en la “Costa Sur”, así definida en el Plan de Ordenación Litoral (POL) de Galicia.Over the last decade, a solid knowledge base has been built up globally in relation to geodiversity, geoheritage identification, conservation and management, which implies legislation on the subject. However, the partial absence of knowledge and information on a scientific level on the part of the Administration regarding national, regional or local “points of geological interest” makes it complex to create appropriate legislation, since something which is not even considered cannot be protected. There is also public ignorance about geological processes and their relationship with biodiversity, as well as their value as natural heritage. This study aims to show the value of ancient sedimentary deposits located on the coast of Galicia as palaeoenvironmental records and landforms. These values are exemplified with deposits of the “Southern Coast”, established in the Coastline Management Plan (POL)

Hacia una diversidad patrimonial europea: geositios en la costa gallega (NW España)

The pervasive lack of awareness in today’s society regarding geological processes and their effects on the landscape is of such magnitude that their relationship to biodiversity and their value as part of the natural heritage is almost completely ignored. In this situation are the Quaternary deposits located on the Galician coast (NW Spain). The lack of awareness of these deposits, or the mere fact that they have either been omitted, or included as other coastal formations in the POL (The Planning Programme for Coastal areas of Galicia), makes their recognition and promotion unfeasible. Taking into account the scientific works and considering the current administrative context, the aim of this study is to demonstrate the importance and scientific and educational interest of the Quaternary sedimentary deposits as palaeoenvironmental records in the hope that this will be recognised as a Geosites by administration, in order to promote their geoconservation as a meaningful and diverse Geological Heritage in European Coastal context.La falta generalizada de conciencia en la sociedad actual en relación con los procesos geológicos y sus efectos sobre el paisaje es de tal magnitud que su relación con la biodiversidad y su valor como parte del Patrimonio Natural casi está completamente ignorado. En esta situación se encuentran los Depósitos Cuaternarios situados en la Costa de Galicia (NW de España). Su falta de conocimiento, o el mero hecho de que, se han omitido o incluido como otras formaciones costeras en la POL (Plan de Ordenación del Litoral de Galicia) hace que su reconocimiento y su difusión sea inviable. Teniendo en cuenta los trabajos científicos y el contexto administrativo actual, el objetivo de este estudio es mostrar su importancia e interés científico y educativo como registros paleoambientales con la esperanza de que alcancen su reconocimiento por parte de la administración como Geositios, con el fin de promover su geoconservación como un Patrimonio Geológico significativo y diverso en el contexto Costero Europeo.This research was partially funded by Project 09SEC015606PR (Xunta de Galicia) and by COMDEMO Project (Plan Nacional de I+D+i: EDU2015-65621-C3-1-R) co-financed with EU ERDF funds.info:eu-repo/semantics/publishedVersio

Geological heritage at risk in NW Spain. Quaternary deposits and landforms of “Southern Coast” (Baiona-A Garda)

Over the last decade, a knowledge base has been built up worldwide in relation to geological heritage and geodiversity, and respective working methodologies. However, the absence of knowledge and technical information by the local, regional and national authorities about geosites makes it difficult to create appropriate legislation and to assure a good management. There is also a public ignorance about geological processes and their relationship to biodiversity, as well as their value as natural heritage. This study focuses on the Autonomous Community of Galicia (NW Spain), specifically the “Southern Coast” area established in the Planning Programme for the Coast (POL) and brings to light the importance of the Quaternary deposits and associated landforms. The study concludes that the Southern Coast should be recognized as an area-type geosite. Taking into account the evaluation of their scientific value, the landforms of Oia and San Xián are proposed as geosites. Legal mechanisms of protection need to be reinforced and new, more specific ones, developed in tandem that make reference to the fact that these landforms exemplify environmental records of the past. This area is unique on a national level due to the scientific and educational value of the deposits. Therefore, they should be proposed to the Spanish Geological Survey (IGME) for inclusion in the general list of geosites of the Spanish State.Manuela Costa-Casais is supported by the Research Programme "Isidro Parga Pondal 2007"-Xunta Galicia. This research was partially funded by Project 09SEC015606PR (2009-2012) "Xeoarqueolox a e reconstrucion paleoambiental. Metodolox a aplicada a contextos arqueoloxico-culturais"-"Geoarchaeology and palaeoenvironmental reconstruction. Methodology applied to cultural and archaeological contexts"-(Conseller a de Econom a e IndustriaXunta de Galicia) and by Portuguese National Funds through the FCT (Fundacao para a Cincia e a Tecnologia) under the project PEst-OE/CTE/UI0039/2011". This paper has been prepared in collaboration with Professor M. Isabel Caetano Alves, during post-doctoral research as "Parga Pondal" carried out by Manuela Costa-Casais at the Centre for Earth Sciences, University of Minho-Centre of Geology, University of Oporto. The authors are deeply grateful to Antonio Martnez Cortizas, the reviewers and the editor for their helpful comments and contributions to the manuscript

The configuration of the cultural landscape during the early Middle Ages (5th-11th centuries): Environmental changes and human activity in the northwest of the Iberian Peninsula

Este trabajo tiene por objetivo aportar algunos elementos para el debate sobre la reconstrucción paleoambien-tal, desde las disciplinas de las Ciencias de la Tierra, centrándose en el período cultural de la Alta Edad Media (siglos V-XI). El artículo se divide en tres apartados. El primero, introduce conceptos básicos sobre la evolu-ción ambiental: ideas generales sobre la reconstrucción paleoambiental y un breve comentario sobre la activi-dad humana en el contexto de los paleoambientes. El segundo, muestra una aproximación metodológica a la reconstrucción desde diferentes disciplinas de las Ciencias de la Tierra. En el tercero, se comentan algunos resultados recientes obtenidos en el noroeste peninsular utilizando ejemplos de archivos que, en este caso, están representados por suelos coluviales y sus señales geoquímicas, analizando los procesos naturales y otros inducidos por la actividad antrópica, con la finalidad de ilustrar los conceptos discutidos en la primera parte. A modo de conclusión, el artículo se cierra con unas pinceladas sobre el paisaje de la Alta Edad Media en el Noroeste Peninsular, a partir de la interpretación y reconstrucción de los datos obtenidosThis paper aims to promote the discussion of some elements relating to paleoenvironmental reconstruction, from the point of view of the Earth Sciences, focusing on the cultural period of the early Middle Ages (5th-11th centuries). The article is divided into three sections. In the first, the basic concepts of environmental evolution are introduced, such as the general ideas of paleoenvironmental reconstruction and a brief commentary on human activity in the context of paleoenvironments. The second section demonstrates a methodological ap-proach to reconstruction from the point of view of different disciplines of Earth Sciences. In the third section, recent results obtained in the northwest of the Iberian Peninsula are commented on, making use of samples of colluvial soils and their geochemical signals obtained from environmental archives. An analysis is made of both natural processes and those caused by human activity, in order to illustrate the concepts discussed in the first part. The article concludes with some comments on the landscape of the early Middle Ages in the north-west of the Peninsula, based on the interpretation and reconstruction of the data obtainedS

Assessment and management of the geomorphological heritage of Monte Pindo (NW Spain): a landscape as a symbol of identity

This study focuses on the granite mountain known as Monte Pindo (627 m above sea level) in the Autonomous Community of Galicia (NW Spain). This territory is included in the area classified as “Costa da Morte” in the “Politica de Ordenación Litoral” (POL) (Coastal Planning Policy) for the region of Galicia. This coastal unit, located between “Rías Baixas” and “Cape Fisterra” has great potential for demonstrating geological processes and its geomorphological heritage is characterized by a high degree of geodiversity of granite landforms. The main objective of our work is to assess the geomorphological heritage of the site, thus revealing its wide geodiversity. We shall analyze and highlight: its scientific value, developing an inventory of granite landforms; its educational valuel and its geotouristic potential. It must be ensured that the Administration understands that natural diversity is composed of both geodiversity and biodiversity. Only then will the sustainable management of Monte Pindo become possible by integrating natural and cultural heritage values. The goal is to ensure that Monte Pindo and its immediate surroundings become a geopark with the aim of promoting local development projects based on the conservation and valorization of its geological heritage.This research was conducted under the research projects CPC2014/009 and R2014/001 funded by the Xunta de Galicia

Coastal retreat and sedimentation during the Last 3000 years. Atlantic coast of NW Spain

During the last glaciation, thick nival and periglacial sediments buried large sectors of the NW coast of Spain. The sediments were mostly eroded by the rising sea level during the Holocene, but in several places they remain, forming sedimentary cliffs. Radiocarbon dates obtained at the topmost layers of these cliffs prove that continental sedimentation was active until very recent times, followed by a retreat of the cliffs. During the first stages of the transgression, the erosion of the cliffs and the changes in the coastal system were controlled by the rising sea-level. Once the sea-level stabilized, the exhumation of inherited landforms, the supply of sediments, and a continuous continental sedimentation became the main factors. The last stages of cliff retreat were almost synchronous with the sedimentation of the upper layers of the deposits.S

Reconstructing Holocene evolution in the archaelogical site of Campo Lameiro (NW Spain): an interdisciplinary approach to geoarchaeology

Fundação para a Ciência e Tecnologia – Programa FAACUniversidade de Coimbra. Faculdade de Letras. Departamento de GeografiaCâmara Municipal de CoimbraDelt

Sea-level change and human occupation over 6000 years on Areoso Island (Ría de Arousa, NW Iberian Peninsula)

Coastal areas are extremely sensitive to variations in environmental conditions. The interaction of marine and continental processes causes a high degree of dynamism, generating depositional formations of great value for palaeoenvironmental reconstruction. This paper focuses on two pedostratigraphic deposits located under the current beach, in close proximity to archaeological tumuli located on Areoso Island (Ría de Arousa, NW Iberian Peninsula). Employing a geoarchaeological approach, sea-level rise, environmental conditions and human occupation over a 6000-year period are interpreted. The results of granulometric and mineralogical data, elemental composition and stratigraphic features, help to identify three successive environments: continental (rock weathering, soil formation and erosion); a transition to a coastal environment; and the establishment of full coastal conditions. The geomorphological evolution of the last 6.0 kyr BP has been controlled by climate, sea-level rise and human activity. The continental facies shows evidence of low sea-level up to 4.8 kyr BP and the first evidence of coastal processes after 3.2 kyr BP. These pedostratigraphic deposits located in an open coastal system improve the Holocene sea-level rise curve in the NW Iberian Peninsula and help to understand the context in which the most important archaeological structures on the island (the tumuli) began to be erodedOpen Access funding provided thanks to the CRUE-CSIC agreement with Springer NatureS

Sea level rise and coastal environmental changes during the Late Holocece. Areoso Island, Ría de Arousa

X Jornadas de Geomorfología Litoral, celebradas del 4 al 6 de septiembre de 2019 en Castelldefels y organizadas por el Institut de Ciències del Mar (CSIC), la Universitat Politècnica de Catalunya (UPC), la Universitat de Barcelona (UB) y la Universitat de Girona (UdG).-- 292 pagesEl islote Areoso, localizado en la Ría de Arousa (Galicia) alberga yacimientos arqueológicos y depósitos edafo-sedimentarios desde la zona intermareal hasta las dunas actuales. Entre 2015 y 2017 se obtuvieron muestras en la zona intermareal, en un sondeo bajo la playa actual y en una columna sedimentaria durante la excavación de un túmulo. Los análisis y dataciones han permitido identificar una secuencia evolutiva con tres etapas. La primera entre 4070-3865 cal. BP y 3407-3249 cal. BP, se caracteriza por el desarrollo de un sistema intermareal. La segunda comenzaría alrededor del 3610-3458 cal. BP y se corresponde con la formación de la playa-duna, identificada en los depósitos bajo la playa actual y en el túmulo. Sobre estos niveles, la fecha de 2277-2153 cal. BP indica la acumulación de facies eólicas, verificada por la identificación malacológica. Estas secuencias permiten definir la evolución morfosedimentaria y contribuyen a ajustar la curva de ascenso del nivel del mar para el NO Península Ibérica desde el Holoceno Medio. Los resultados concuerdan con otras investigaciones sobre el litoral gallego, siendo esta la primera secuencia completa en un ambiente no lagunar.The Areoso islet, located in the RÌa de Arousa (Galicia), contains archaeological and edapho-sedimentary deposits from the intertidal zone to the recent dunes. Between 2015 and 2017, samples were taken in the intertidal zone, in a sounding under the actual beach and in a sedimentary column during the excavation of a tumulus. The C14 analyzes and dates have allowed us to identify an evolutionary sequence with three stages. The first between 4070-3865 cal. BP is characterized by the development of an intertidal system. The second one would start around 3610-3458 cal. BP and corresponds to the formation of the beach-dune, identified in the deposits under the current beach and in the tumulus. On these levels, the date of 2277-2153 cal. BP indicates the accumulation of aeolian facies, verified by the malacological identification. These sequences allow us to define the morphosedimentary evolution and contribute to adjust the sea level rise curve for the NO of the Iberian Peninsula from the Middle Holocene. The results agree with other researchs on the Galician coast, this being the first complete sequence in a non-lagoon environmentS

Evolution of a coastal area during the early Middle Ages in the NW of the Iberian Peninsula

En el presente trabajo se estudia la evolución de un tramo costero de la Ría de Vigo (NW de la península Ibérica) desde época romana hasta el siglo XVII, prestando particular atención a la Alta Edad Media. Desde el punto de vista arqueológico, la importancia del sector radica en la presencia de una salina de época romana, en uso desde los siglos II BC a III-IV AD, y su abandono para dar paso a la instauración de una iglesia y una necrópolis en la Alta Edad Media (a partir de los siglos IV-V AD). Se muestrearon, con alta resolución, tres secuencias edafo-sedimentarias y se analizaron diversas propiedades físico-químicas (pH, granulometría, contenido en C, N, S, P, Fe, As) y la composición mineralógica, con el fin de determinar la naturaleza de las distintas facies presentes, los procesos implicados y las causas asociadas. Los resultados indican modificaciones en la costa entre finales del periodo romano y comienzos de la Alta Edad Media, con una evolución del medio desde una dinámica costera, con formaciones de marisma-lagoon costero, a una dinámica eólica, con dunas. Dicho cambio es coincidente con el cese de la explotación romana de sal y el inicio del periodo Frío Altomedieval. Estos resultados son similares a los encontrados en otros puntos de la Ría de Vigo. En los tres sectores comparados (Rosalía de Castro, Toralla y Hospital), a la par que se produce la progradación de las formaciones de marisma y duna, el uso antrópico del sector cambia. Aunque la pauta climática presenta un papel importante en la evolución de este sector, los cambios en la línea de costa que se detectan entre ambos periodos culturales pudo estar determinada también por causas socioecómicasThis paper focuses on the evolution of a coastal stretch of the Ria de Vigo (NW Iberian Peninsula) during the early Middle Ages, which presents an important archaeological site with a roman salt mine. Salt exploitation in the Roman period ceased around the AD 3rd-5th centuries, and was followed by the establishment of a churche and a cemetery during the Middle Ages. The properties (pH, grain size, C, N, S, P, Fe and As, and mineralogical composition) of three pedo-sedimentary sequences were analysed in order to identify the different environmental changes that affected this sector. The results suggest signifcant changes occurred in the coast from the late Roman period (AD 3rth-5th centuries) into the early Middle Ages (AD 5th-6th centuries), with an evolution from a marine-continental dynamics, with formation of salt marshes, to a wind dynamics, with dune formations. This change is consistent with the abandonment of the Roman salt exploitation and the beginning of Cold Dark Ages. These results are similar to those found in other areas of the Ría de Vigo. In the three sectors compared (Rosalia de Castro, Toralla and Hospital) land use changed while the progradation of marsh and dune formations occurred. Although climate may have played a major role in the evolution of this sector, the changes in the coastline between the two cultural periods could be also related to socio-economic causesS