Search results for "marl"

Late Cretaceous palaeoenvironments expressed by the clay mineralogy of Cenomanian–Campanian chalks from the east of the Paris Basin

2005

Abstract The clay fraction of Cenomanian–Campanian chalks cored at Poigny and Sainte-Colombe, close to Provins (east-south-east of Paris), includes variable proportions of smectitic minerals, illite and kaolinite. The smectitic sediments (which constitute the background of low-terrigenous supply throughout the stratigraphic interval) resulted mainly from the warm, humid climate and high sea level that prevailed during Late Cretaceous in this area. During the Late Turonian, the smectitic sedimentation was interrupted by significant detrital inputs of illite and kaolinite. This reflected tectonic rejuvenation of landmasses coeval with an explosive volcanism expressed by the occurrence of bent…

1991

The Triassic of the NW Iberian Ranges consists of two carbonatic formations equivalent to the Upper Carbonatic Formation of the Muschelkalk Facies and pass laterally into siliciciastic deposits to the NW. Fossillocalities have been found in both formations. Taphonomic and sedimentologic studies allow for the interpretation as autochthonous associations of the infaunal Bivalves of shallow water marine environments with siliciciastic input. Three faunal associations have been distinguished: 1. Costatoria-Lyriomyophoria association, found in the lower carbonatic formation and the equivalent siliciciastic formation; 2. «Teruel Fauna» association, found in the upper carbonatic formation; 3. Ling…

Mass mortality or exceptional fossilization ? The case of the early and middle Toarcian fossiliferous beds from the Digne-Les-Bains area (southeaster…

2003

Abstract The latest Domerian to late Toarcian sedimentary series (from −190 Ma up to −180 Ma) from the « Réserve Géologique de Haute-Provence » (southeastern France) yields two kinds of remarkable fossiliferous beds. The greatest interest of the early Toarcian type is the occurrence of ichtyosaur remains (at least in six sites) among many other fossils such as ammonites, belemnites, bivalves, wood. The middle Toarcian type is specifically rich in ammonites and nautiluses. Litho- and biostratigraphical, palaeontological, sedimentological and geochemical analyses allow us to determine whether these fossiliferous beds are the results of mass mortalities, linked or not to biological crisis, o…

Shallow structures at the outer Calabrian accretionary wedge (NW Ionian Sea): new insights from recently migrated reflection data

2010

Terra Nova, 00, 000–000, 2010 Abstract Post-stack time migration of a set of seismic reflection profiles reveals details of the stratigraphic–structural setting of the outermost Calabrian accretionary wedge, in the NW sector of the Ionian Sea, with particular emphasis on the Messinian stratigraphy and the deformation style of the thin frontal portion of this wedge. A structural style and seismic facies analysis, calibrated by refraction data, images a general bipartition of the Messinian evaporite deposits: the `lower subunit', consisting mainly of salt, appears to have undergone ductile-flow deformation, and the `upper subunit', consisting mainly of gypsum and marls, appears to be characte…

A sequence analyzed from the basin to the platform : the Middle Oxfordian calcareous succession in southeastern France

2004

Abstract Middle Oxfordian sedimentation is very homogeneous in southeastern France. It is characterized by a specific alternation of marls and fine-grained limestones (G. transversarium Zone). This work shows that sets of calcareous beds allow accurate stratigraphic correlations in various paleogeographic areas, from the shallow Jura platform to the deep Dauphinois basin. Following a rifting period, this sedimentation illustrates a doming period with decreasing subsidence and water depth. This corresponds to the establishment of a wide marine area more favourable to carbonate sedimentation. Considering sequence stratigraphy, some slight variations occur in the sediment record and lead to in…

Miocene lithological, foraminiferal and palynological data from the Belverde borehole (Portugal)

2021

XVIII Jornadas de Paleontología, 2002 Preliminary data on litho stratigraphy and biostratigraphy of the Belverde borehole (http://www. dct.Jct.unl.pt/ SondagemISondagem/colunalindex_col.html) is presented. The borehole attained 619,77 m of depth, crossing 130 m of Plio-Pleistocene and 460 m of Miocene dep osits. Main lithologies are fine sands , marl s and biocalcarenites. A coral reef was recognized in the lower part of the borehole (530-585 m). Gamma ray, neutrons and sonic diagraphies were obtained. Eight 87Sr/86Sr isotopic ages (H. Elderfield, Cambridge University)and the presence of some of the main planktonic foraminifera markers were used to establish the chronostratigraphic framewor…

In situ remediation of polluted Spolic Technosols using Ca(OH)2 and smectitic marlstone

2014

Technosols are soils developed on non-traditional substrates and containing large quantities of materials mostly due to intensive human industrial activity, such as artefacts. The increasing number of sites affected by Technosols and their impact on the environment as growing media for plants or as source of pollutants require an understanding of their functioning and evolution, above all the knowledge on the transport of toxic substances from contaminated technogenic soils to groundwater. A case study on properties, remediation and evaluation of Technosols made up by vitrified fly ash and glass–ceramics in Italy was carried out. Original technogenic soils, classified as Spolic Technosols (…

Using Macroelement Content to Characterize Surficial Water Quality of Artificial Reservoirs

2021

Abstract The quality of surface waters in the territory of Poland, despite the implemented remedial measures, is mostly classified as bad. This article presents the results of research on the composition of water macroelements in 24 artificial reservoirs located in Opole province (southern Poland), searching for the reasons behind their pollution. Concentrations of the anions F−, Cl−, Br−, NO2−, NO3−, PO43− and SO42− and cations Na+, NH4+, K+, Mg2+ and Ca2+ were taken into account. An analysis of seasonal changes was carried out and, on the example of a dam reservoir (Turawa Big Reservoir), a multi-point analysis of the distribution of ion concentrations in water at the reservoir surface w…

Ciclos pelíticos de bahía Interdistributaria del nivel intramareal inferior del grupo Roda-Oroel (sector occidental del paleodelta de Ager, Lérida)

1984

The deposits of the ancient Ager deltaic system (Lérida, Spain) are characterized in some way by the existence of cycles constituted, in a large scale, by alternances of pelites and sandstone bodies. According to geological literature these deposits represent bay marls and stream-mouth-bars, in the eastern-most counterpart. In this area sorne pelitic sections show a pronounced cyclical pattern devoid to repetitions of two terms: A marly bioturbated one, and the other one, constituted by undisturbed delicately laminated clays. Part of the deposits of the "Intramarea1 Inferior" level (''Tramo Superior" of the Roda-Oroel depositional system) in the area comprised between La Régola cementery an…

Seismogenic rotational slumps and translational glides in pelagic deep-water carbonates. Upper Tithonian-Berriasian of Southern Tethyan margin (W Sic…

2017

Abstract Soft-sediment deformation structures (SSDSs), which reflect sediment mobilization processes, are helpful to identify punctual events of paleoenvironmental stresses. In the upper Tithonian-Berriasian calpionellid pelagic limestone of the Lattimusa Fm. outcropping in the Barracu section (W Sicily), paleoenvironmental restoration reveals the occurrence of a deep-water flat basin, characterised by undeformed planar bedding, laterally passing to a gentle slope where the deformed horizons alternate with undeformed beds. Here, two types of gravity slides have been differentiated on the basis of different kinds of SSDSs, brittle deformation, involved lithofacies, geometry and morphology. T…