24 research outputs found
Quantitative taphonomy of the Cacela site (late Tortonian; Algarve, S Portugal)
A quantitative taphonomic analysis were performed in the fossil assemblages of the late Tortonian of the
lower-mid part of the Cacela Formation (Cacela, Algarve, S Portugal). Taphonomic results, together with
sedimentological analysis and the faunal assemblages, allow to inferring palaeoenvironmental changes.
The upper Tortonian sedimentation started with fan-delta conglomerates that quickly changed to outerplatform
silty marls deposited in a setting with a relatively low sedimentation rate as indicated by the
concentration of glauconite. Higher up into the section, a progressive shallowing trend is inferred, and
sediments of inner platform settings were forme
Ипотека морского судна в контексте восстановление отечественного торгового флота в Украине
Торговельне мореплавство – одна з тих галузей світової економіки, яка має найбільш швидкий розвиток у наш час. Перш за все, це пов’язано із прискоренням міжнародного товарообміну. Наростання обсягів міжнародної торгівлі, у якій прагне приймати участь також Україна, обумовлює необхідність адекватно швидкого зростання її транспортної галузі. Попри значний транспортний потенціал, що має Україна, багато в чому завдячуючи її географічному положенню, стан вітчизняного транспортного комплексу й, особливо, його морської ланки, потребує покращення. Це, в свою чергу, безпосередньо залежить від правового регулювання, що впорядковує такі процеси
Oscilaciones eustáticas e implicaciones climáticas en el tránsito Neógeno-Cuaternario en la isla de Sal (archipiélago de Cabo Verde)
Solution pipes interpreted as a cryptokarst separate large-scale cross-bedded megaforms of shallowmarine
calcarenites deposited at the Neogene-Quatemary transition in Cape Verde Islands. This
implies that depositional phases were followed by subaerial exposure of the cemented calcarenites
during subsequent falls of sea level, and accumulation of unconsolidated eolianites which supported
a vegetal cover that promoted the cryptokarst. The process was repeated several times.
A widespread, more recent karstification with red silty clay filling of voids may represent the aridification
of climate at the beginning oi the Quaternary and the increased supply of Saharan dust by
Trade Winds
Augmented Reality in a Hiking Tour of the Miocene Geoheritage of the Central Algarve Cliffs (Portugal)
Acceso electrónico sólo desde el IGMEEight sites with geological (including palaeontological and geomorphological) interest (geosites) representative of the Lower and Middle Miocene carbonate deposits near Albufeira in central Algarve (southern Portugal) have been selected based on our extended working experience. The sites can be visited by hiking in a 1-day field trip. A virtual 3D tour of the georeferenced sites was produced using augmented reality technique and geoinformatic tools which integrate thematic digital layers such as geological maps and orthophotos. Every stop in the tour includes descriptive and graphic elements that can be viewed in free virtual globes (e.g. Google Earth) combined with diagrams, photographs and information sheets that quantitatively assess the cultural-touristic, educational and scientific value of the geosites. A virtual flight itinerary compatible with video formats in the new free technologies (smartphones, tablets and iPads) is also presented.Departamento de Geología, Universidad de Salamanca, EspañaGeoBioTec, Departamento de Ciências da Terra, Universidade Nova de Lisboa, PortugalDepartamento de Estratigrafía, Universidad Complutense de Madrid, EspañaMuseo Nacional de Ciencias Naturales, Consejo Superior de Investigaciones Científicas, EspañaLaboratório Nacional de Geologia e Energia, Portuga
Tsunami vs. Storm surge deposits: A review of the sedimentological and geomorphological records of extreme wave events (EWE) during the holocene in the gulf of Cadiz, Spain
The Gulf of Cadiz region of Spain has undergone many studies examining Holocene tsunami and storm deposits. Some of the studies aimed at determining recurrence intervals of events interpreted of tsunamigenic origin.A review of geomorphologic, sedimentary and paleontological features of these deposits suggests that only a few of them can be accurately ascribed to tsunami events; instead, most of them lack conclusive evidence of a tsunamigenic genesis and should be referred to as generated by extreme wave events (EWE).Peer reviewe
El efecto de los ciclos climáticos en las variaciones del nivel del mar
Ejemplar dedicado a: Miscelánea en homenaje a Emiliano Aguirre. GeologíaPeer reviewe
El problema del Neógeno Superior en la Cuenca del Duero: nuevos datos paleontológicos (invertebrados) en el sector Peñafiel-Almazán*
Junto a las características litoestratigráficas generales del Neógeno del sector Suroriental de la Cuenca del Duero se aportan nuevos datos paleontológicos (Gasterópodos y Ostrácodos) delimitando una sucesión de acontecimientos y
cambios en las asociaciones a través de la columna estratigráfica general.
Varios son los taxones de Gasterópodos destacables como Hydrobia schlosseri,
H. gr. deidieri, Valvata, Bithynia, Planorbis, Melanopsis y Theodoxus entre otros. En
cuanto a los Ostrácodos, su sucede la aparición de ?Paracandona, Gen. indet. sp. 1,
Lineocypris, Subulacypris y Candona aff. bitruncata especialmente.
Amén de establecer la correlación entre las diferentes secciones, el conjunto paleontológico
apunta a una edad más moderna que la de los depósitos situados hacia
el centro de la Cuenca. Estos datos no estarían en contradicción con la relación entre
la posición topográfica y la pendiente depositaria general.
La presencia de formas atribuibles a Cyprideis torosa en los Valles de Fuentidueña
plantea un problema cronoestratigráfico precisándose la necesidad de revisión de
la distribución del taxón.
[ABSTRACTS]
Together with the general lithostratigraphic characteristics of the
Neogene of the southeast sector of the Duero Basin, new paleontological data are provided
(Gastropoda and Ostracoda) which demarcate a succession of events and changes
in the assemblages through out the general stratigraphic column.
There are several out standing taxons of Gastropoda such as Hydrobia schlosseri,
H. gr. deidieri, ValvaTa, Bithynia, Planorbis, Melanopsis and Theodoxus. Regarding the Ostracoda, the appearence was noted specially of ?Paracandona, Gen. indet. sp.
1, Lineocypris, Subulacypris and Candona aff. bitruncata.
As well as establishing the correlation between the different sections, the paleontological
group also points to a more modern age than those of the beds situated
towards the centre of the basin; this would not conflict with the general deposit slope
of such beds and their relation with the topographic level.
The presence of forms attributable to Cyprideis torosa, in the Valles de Fuentidueña
poses a chronostratigraphic problem and suggests the need to revise the age of
the bed or the Ostracoda distribution
Virtual 3D tour of the Neogene palaeontological heritage of Huelva (Guadalquivir Basin, Spain)
Paleoenvironmental significance of C and O isotopic signal in last interglacial gastropod Dendropoma shell concentrations from Canary (Spain) and Sal (Cape Verde) islands.
Se estudia el significado paleoambiental de los isótopos estables de C y O de la concha del
gasterópodo irregular Dendropoma, considerado un marcador del nivel medio del mar, procedentes
de terrazas pertenecientes al Ultimo Interglaciar de Fuerteventura y Lanzarote (Islas Canarias, España),
y de la isla de Sal (Cabo Verde). Se compara con la señal actual de Dendropoma sp. de la isla de Sal,
y D. petraeum del Cabo de Palos (Murcia, España). El rango de valores es casi siempre menor a 1 ä,
excepto para ä13C de los ejemplares de Fuerteventura (3,57‰) y ä18O de los de Cabo de Palos
(2,09‰). La diferencia entre ä18O de los ejemplares de Fuerteventura con respecto a los de la isla de
Sal, si la salinidad no cambió, probablemente refleja una diferencia de 3-4 ºC en la temperatura de la
superficie del agua del mar (SST) de ambas zonas, similar a la que existe actualmente. Para la isla de
Sal, en ausencia de cambios de salinidad y volumen de hielo, la diferencia de SST entre el Ultimo
Interglacial y el Presente Interglacial sería de 2 ºC.
[ABSTRACT]
We study the paleoenvironmental significance of the C and O isotopes of the irregular
coiled gastropod Dendropoma, a remarkable biological marker of mean sea level, of sediments aged
as Last Interglacial from Fuerteventura and Lanzarote (Canary Islands, Spain), and from the Sal
Island (Cape Verde). Recent Dendropoma sp. from the Sal Island and D. petraeum from Cabo de
Palos (Murcia, Spain) are also utilized. Range of results generally is lower than 1 ä, both for the C
and O, except for the ä18O in Cabo de Palos (2,09‰), and for the ä13C from Fuerteventura (3,57‰).
Differences between ä18O shells of the Last Interglacial (LI) from Fuerteventura with respect to that
of Cape Verde, if salinity do not changed, probably reflects differences of 3-4 ºC in the sea surface
temperature (SST), similar to the Recent. In Sal Island, if salinity and ice-volume do not changed, the
difference between SST of the LI and Recent probably was of 2 ºC
The Upper Neogene of the Souss Valley (Agadir, S. of Morocco)
The present contribution shows the first approach to the sedimentological and palaeontological characteristics of two representative Upper Neogene sections of the Souss Valley (Agadir, S. of Morocco): Tildi and Ait Aouth, thick of 40 and 85 m, respectively. Taphonomic studies show several pauci and poli-specific Mollusks shell concentrations (more than 50% of bioclasts), in alternance with levels of more dilution of shells (less than 5%). Bivalves, Gastropods an Cirripeds are the most common macrofauna. All the levels are afected by an important fossil-diagenetic carbonate dissolution. The benthic assemblages are monotonous, and the planktonic Foraminifers are very scarce, whereas we can aproximate the geological age of the sections. We interpret marine warm palaeoenvironments of inner platform, with progressive shallowing, according the sedimentological and palaeontological dat