Sedimentology

In the Cadomian orogenic belt a package of glacigenic sedimentary deposits have been recently described in the Armorican Massif (Normandy, France). The Granville Tillite Member, the middle part of the upper Granville Formation, is late Ediacaran in age. Maximum depositional ages of the pre- and syn-glacial sedimentary deposits obtained by LA-ICP-MS U–Pb detrital zircon dating indicate a maximum age of 561 ± 3 Ma. Combined with geochronological data on the previously described glacial deposits in Cadomia, West Africa, Arabia and Iran, the Granville Tillite Member appears to represent an Upper Ediacaran Glacial Period in northern peri-Gondwana, clearly younger than the c. 580 Ma old Gaskiers glaciation. Detailed mapping and analysis of the depositional regime of two sections near the city of Granville are indicative of two independent glaciomarine lower and upper tillite deposits separated by a distinct conglomeratic marker horizon, evidently a massive gravel beach horizon deposited d...

Male Largemouth Bass were sampled from two locations in Lake Mead (USA), a site influenced by treated municipal wastewater effluent and urban runoff (Las Vegas Bay), and a reference site (Overton Arm). Samples were collected in summer (July '07) and spring (March '08) to assess general health, endocrine and reproductive biomarkers, and compare contaminant body burdens by analyzing 252 organic chemicals. Sperm count and motility were measured in spring. Contaminants were detected at much higher frequencies and concentrations in fish from Las Vegas Bay than Overton Arm. Those with the highest concentrations included PCBs, DDTs, PBDEs, galaxolide, and methyl triclosan. Fish from Las Vegas Bay also had higher Fulton condition factor, hepatosomatic index, and hematocrit, and lower plasma 11-ketotestosterone concentration (KT). Gonadosomatic index (GSI) and sperm motility did not differ between sites, but sperm count was lower by nearly 50% in fish from Las Vegas Bay. A positive a...

Adult male Common Carp were sampled in 2007/08 over a full reproductive cycle at Lake Mead National Recreation Area. Sites sampled included a stream dominated by treated wastewater effluent, a lake basin receiving the streamflow, an upstream lake basin (reference), and a site below Hoover Dam. Individual body burdens for 252 contaminants were measured, and biological variables assessed included physiological [plasma vitellogenin (VTG), estradiol-17β (E2), 11-ketotestosterone (11KT)] and organ [gonadosomatic index (GSI)] endpoints. Patterns in contaminant composition and biological condition were determined by Principal Component Analysis, and their associations modeled by Principal Component Regression. Three spatially distinct but temporally stable gradients of contaminant distribution were recognized: a contaminant mixture typical of wastewaters (PBDEs, methyl triclosan, galaxolide), PCBs, and DDTs. Two spatiotemporally variable patterns of biological condition were recognized: a ...

In this report we review 239 records of 86 species and one hybrid recently assessed by the California Bird Records Committee (hereafter the Committee or CBRC). Of these records, 160 were accepted, yielding an acceptance rate (68%) consistent with the most recent reports (Roberson 1993, Patten and. This rate, however, is lower than in earlier reports, primarily for two reasons. First, in the recent reports, we have voted on a substantial number of historical records that have been published but not reviewed, and a higher percentage of these records has been rejected. Second, the Committee has become more conservative recently. For this report, records dating from 1956 to 1991 were reviewed, the majority being from the summer of 1990 through the spring of 1991. This report adds no species to the California list, which stands at 586 species. This "inactivity" is temporaw, as the acceptance of the Alder Flycatcher (Empidonax alnorum) will be reported in the 17th report and that of Great Frigatebird (Fregata minor) and Fork-tailed Flycatcher (Tyrannus savanna) in the 18th. Other potential additions to the state list under review are the Dark-rumped Petrel (Pterodroma phaeopygia), Manx Shearwate, r (Puffinus), and Black-tailed Gull (Larus crassirostris). The Band-rumped Storm-Petrel (Oceanodroma castro), on the state list by means of a single sight record, is being reconsidered. Outstanding decisions included in this report are the acceptance of California's second record of Stejneger's Petrel (Pterodroma 1ongirostris) and the rejection of prospective first state records of Townsend's Sheareeater (Puffin us a u ricu la r/s), the Band-tailed (Larus belcheri), Iceland (L. glaucoides) and Swallow-tailed Gulls (Creagrus furcatus), and the Oriental Turtle-Dove (Streptopelia orientalis). All records reviewed by the CBRC are archived at the Western Foundation of Vertebrate Zoology, 439 Calle San Pablo, Camarillo, CA 93010. All CALIFORNIA BIRD RECORDS forms of documentation (written descriptions, photographs, recordings, videotapes, etc.) are housed at the foundation, where they are organized taxonomically and by CBRC record number. All are available for public review. The CBRC solicits information on all occurrences in California of species on its Review List (see Roberson 1993) and requests that documentation be sent to Michael A.

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La intermitencia ocurre cuando una senal alterna explosiones caoticas con periodos de cuasi regularidad llamados fases laminares. Se ha estudiado que el numero de explosiones caoticas se incrementa en funcion de la variacion de un parametro externo, entonces el fenomeno de intermitencia es un camino continuo de movimientos regulares a caoticos. Entre las aplicaciones mas importantes en mecanica de los fluidos, donde el fenomeno de intermitencia se presenta, se encuentra la transicion a la turbulencia y la turbulencia misma. La evaluacion correcta de este fenomeno contribuye a una mejor prediccion de estos temas. En este trabajo se emplea una nueva teoria desarrollada para estudiar intermitencia en mapas (E. del Rio y S. Elaskar, Int. J. Bifurcation and Chaos, 20(4):1185–1191 (2010), S. Elaskar et al., Physica A, 390:2759–2768 (2011)) para ser aplicada a un sistema dinamico continuo que resulta del truncamiento a tres ondas de la ecuacion derivada no lineal de Schrodinger (DNLS), la ...

Bangladesh government has taken the initiative to construct the Padma Bridge from Mawa point that will ease our communication system as well as boost our GDP. The area is suffering from water logging problem and the problem can be increased by different mega construction for development purposes. The water logging problem is seen this area for various anthropogenic causes like unplanned construction and random sand filling by different government, private organizations and individuals, construction of micro dam by land owners, embankment by local government. Siltation is one of the factors of water logging. A remote sensing based approach discloses that in 1991, total water body in the study area was 10,697 hectares where as in 2014, that was 14,930 hectares. Water logging problem hampers the social, physical, environmental life of the area. It also has the negative impact on economy. To overcome this problem, some measures can be taken including awareness programme, legal action an...

We investigate the sedimentary record of Lago Thompson, a small lake (area 1.1 km2, watershed ∼8 km2) located at an elevation of 750 masl in Northern Chilean Patagonia (45.38 °S, 71.47°W). At Present, the climate conditions around the lake are relatively dry, with annual precipitation averaging 500 mm. The goal of this study is to evaluate the natural climate variability over the Last Millennium in Northern Chilean Patagonia and its impact on the environment. The coring site was selected after a bathymetric survey using an echo-sounder. Several short cores were retrieved in 2008 using an Uwitec gravity corer: the length of the cores ranges between 124 and 132 cm. The preliminary age model is based on 4 AMS radiocarbon ages measured on bulk sediment and organic macro-remains. The radiocarbon ages demonstrate that the sediment cores cover the last 850 to 950 years. This sediment record, which is characterized by accumulation rates ranging between 1 and 3 mm/yr, can therefore be studied at decennial to centennial resolution. To reconstruct past changes in climate and the environment, we conducted a multiproxy study combining sedimentological, mineralogical and geochemical analyses (LOI 105, 550 and 950°C, biogenic silica content, magnetic susceptibility, tephrostratigraphy, bulk organic geochemistry, bulk mineralogy by X-ray diffraction, and inorganic geochemistry by ITRAX core scanner and ICP-AES). Visual descriptions and X-ray radiographies demonstrate that the sediment record is relatively undisturbed. The sediment is composed of light brown organic-rich clayey material. The lower part of the core (below 75 cm) is finely laminated whereas the upper part is more homogeneous. Magnetic susceptibility values highlight two tephra layers that represent explosive eruptions of volcanoes from the southern volcanic zone of Chile (Hudson, Cay, or Macá volcanoes). The biogenic silica content of the sediment retrieved in Lago Thompson is high (40 to 80%), and probably related to the small catchment to lake surface ratio, which limits the supply of terrestrial particles to the lake. The inorganic content of the sediment is very low. Some clay minerals, quartz and feldspars were identified by X-ray diffraction. This observation is in agreement with the low C/N ratio (∼ 8-9) of the bulk organic matter, providing evidence that most of the organic particles originate from aquatic productivity. The high organic matter content (mean 15%, concentrations reaching up to 20%) and its low C/N ratio provide evidence that the lake productivity remained high over the last 900 years. Higher concentrations in biogenic silica and organic matter between 1550 and 1800 AD could be interpreted as drier climate conditions in the Andes of Northern Patagonia during the Little Ice Age. Further research will focus on biological proxies (diatom, chironomid, pollen) to improve this interpretation. This research is funded by Chilean and Belgian projects (Fondecyt project number 1070508, and FNRS "crédits au chercheur" 1360 2007-2010, respectively).

O Sistema de lagos do médio rio Doce, região leste do estado de Minas Gerais, tem sido estudado sob a perspectiva de diferentes áreas do conhecimento destacando-se a geológica, a sedimentológica, a geomorfológica, assim como, a ecológica e a limnológica com ênfase nos aspectos biológicos, o que vem subsidiando o melhor entendimento tanto no que diz respeito a fatores relacionados à sua origem como, também, ao funcionamento do ambiente como mantenedor da biodiversidade local. O complexo lacustre dessa região compreende um conjunto de cerca de 150 lagos sendo que, aproximadamente 40 deles, encontram-se inseridos dentro do maior resquício de Mata Atlântica do estado de Minas Gerais, o chamado Parque Estadual do Rio Doce (PERD). A respeito da formação desses lagos existe o consenso de que houve barramento dos tributários do rio Doce, intensa sedimentação dos canais principais desse sistema e uma reorganização da rede de drenagem regional. Entretanto, muitos desses lagos encontram-se em ...

The Francistown plutonic rocks at the southwestern margin of the Zimbabwe craton consist of three igneous suites: Sanukitoid, Tonalite-Trondhjemite-Granite (TTG) suites and High-K granites. The TTG suite is subdivided into High Aluminum-TTG (HA-TTG) and Low Aluminum-TTG (LA-TTG) sub-suites. Their Rb-Sr isotope systems were partially homogenized by post-crystallization thermo-tectonic events, in which hydrothermal solutions and migmatization played an important role. Therefore, the Rb-Sr isochron age of 2427±54 Ma can only be regarded as a lower limit to the Francistown plutonic rock age. The large errors in the Sm-Nd isochron dates of Francistown granitoids indicate that these dates are not really constrained. In this study we compared the rock types of Francistown and adjacent areas, adopting the precise U, Th-Pb single zircon SHRIMP ages from the Vumba area as references. For TTG and Sanukitoid suites, the age we adopted is ca. 2.7 Ga, which is close to their depleted-mantle Sm-Nd model ages (T DM ). For High-K granites, the age adopted is ca. 2.65 Ga, which is also close to their Sm-Nd isochron age. The highest e Nd t values of Sanukitoids and TTG are +2.1 and +2.3, respectively. The positive e Nd t values and trace element geochemistry support partial melting of a depleted mantle and young oceanic crust for the genesis of Sanukitoid and the TTG suites respectively. The lowest e Nd t values of Sanukitoids and TTGs are À1.0 and À1.1, respectively, indicating contamination by continental crust, up to 10 and 14%, respectively. The e Nd t values of TTG decrease with decreasing Al 2 O 3 and Sr contents and increasing Eu negative anomalies (Eu*-Eu), suggesting that the TTG magmas underwent a coupled fractionation crystallization and crustal contamination, and that the LA-TTG was the product of the fractionation and contamination of the HA-TTG subsuite. In contrast, negative e Nd t values for the High-K granites (from À0.4 to À3.5) indicate the involvement of LA-TTG and some materials from an old continental crust in their genesis. The products of partial melting of both oceanic and continental crusts at the south-western margin of the Zimbabwe craton occurred within a short time interval (from 2.7 to 2.65 Ga ago) suggesting that the Francistown plutonic rocks were formed in a active continental margin environment, where a young ocean plate (Limpopo oceanic plate) subducted underneath an old continental plate (Zimbabwe craton).

An integrated study of magnetic mass susceptibility (MS), bulk stable isotopes and calcareous nannofossil paleoecological changes is undertaken on the late Maastrichtian of the Elles section, Tunisia, spanning the last ca. 1 Myr of the Cretaceous. A cyclostratigraphic analysis reveals the presence of Milankovitch frequencies and is used for proposal of two distinct orbital age models and to provide ages of important stratigraphic horizons, relative to the age of the Cretaceous-Paleogene boundary (K-PgB). Principal component analysis (PCA) performed on the nannofossil assemblage reveal two main factors, PCA1, mostly representing fluctuations of D. rotatorius, P. stoveri, Lithraphidites spp., Retecapsa spp., Staurolithites spp., Micula spp., and PCA2, mostly representing fluctuations of A. regularis, C. ehrenbergii, Micula spp., Rhagodiscus spp., W. barnesiae and Zeugrhabdotus spp. Variations in PCA1 and PCA2 match changes in bulk δ 13 C and δ 18 O, respectively, and suggest changes in surface-water fertility and temperatures and associated stress. The variations in abundances of high-latitude taxa and the warm-water species Micula murus and in bulk δ 18 O delineate fast changes in sea-surface paleotemperatures. As in many other sites, an end-Maastrichtian greenhouse warming is highlighted, followed by a short cooling and an additional warm pulse in the last 30 kyr of the Maastrichtian which has rarely been documented so far. Orbital tuning of the delineated climatic events is proposed following the two different age models. Calcareous nannofossil assemblages highlight a decrease in surface-water nutriency, but their species richness remains high through the latest Maastrichtian, indicating, in Tunisia, a weak impact of Deccan volcanism on calcareous nannoplankton diversity before the mass extinction.

Stoker J.J. Water Waves [Book]. New York : Interscience Publishers Inc., 1957. p. 567. References Using the wave gauge recordings, Stoker's equation was used to calculate the depth of the hydraulic bore and was further compared with the recorded data based on the experimental values and recorded data. It was found that the measured hydraulic bore depth was significantly larger than the values obtained through the equations. Both the tracking of the bore front and the tracking of the particles are still underway.

Drilling at ODP Site 641 (on the western margin of Galicia Bank, off northwestern Spain) revealed a thin, but pro nounced, interval of black shale and gray-green claystone. Our high-resolution study combines the sedimentology, micropaleontology (palynomorphs and others), organic and inorganic geochemistry, and isotopic values of this layer to demonstrate the distinct nature of the sediment and prove that the sequence represents the local sedimentary expression of the global Cenomanian/Turonian Oceanic Anoxic Event (OAE) of , Arthur and, also called the Cenomanian/Turonian Boundary Event (CTBE). The most striking evidence is that the strong positive 5 13 C excursion characterizing the CTBE sequences in shallow areas can be traced into a pronounced deep-sea expression, thus providing a good stratigraphic marker for the CTBE in various paleosettings. The isotopic excursion at Site 641 coincides with an extremely enriched trace metal content, with values that were previously unknown for the Cretaceous Atlantic. Similar to other CTBE occurrences, the organic car bon content is high (up to 11%) and the organic matter is of dominantly marine origin (kerogen type II). The bulk mineralogy of the CTBE sediments does not differ significantly from the general trend of Cretaceous North Atlantic sediments (dominance of smectite and zeolite with minor amounts of illite and scattered palygorskite, kaolinite, and chlorite); thus, no evidence for either increased volcanic activity nor a drastic climatic change in the bor derlands was found. Results from Site 641 are compared with the CTBE section found at Site 398, DSDP Leg 47B (Vigo Seamount at the southern end of the Galicia Bank).

I analyzed spores, pollen and organicwalled algal remains in Middle Miocene deposits that filled a paleosinkhole at Tarno ´w Opolski, in the Upper Silesian Upland, Poland. Middle Triassic limestone bedrock in the study area underwent intense karstification under relatively warm and humid climate, resulting in development of numerous sinkholes. As the corrosion reached non-karstified marls, flowing water in the vadose zone was plugged and meteoric waters thus accumulated, leading to pond development. This palaeobotanical study was undertaken to ''reconstruct'' the fossil freshwater algae community and vegetation in and around the water body. Chlorophyta such as Botryococcus, filamentous algae from the family Zygnemataceae, mainly Mougeotia, Spirogyra and Zygnema, and desmids were important components of the algal assemblage. Most of the identified algae prefer mesotrophic to eutrophic conditions, and are characteristic of stagnant or slow-flowing shallow water. Among the free-floating and rooted plants were Salviniaceae/Azollaceae (probably Salvinia), Nuphar, Potamogeton, and carnivorous taxa such as Utricularia and probably Aldrovanda. The water body was surrounded by swamp vegetation composed of herbs such as Typha, Sparganium, Alismataceae and others, and riparian forests. The upper portion of the sediment section contains abundant pollen of swamp forest taxa such as Taxodium/Glyptostrobus, Nyssa and Alnus. The paleobotanical remains from the sinkhole at Tarno ´w Opolski suggest it was a shallow water body that was probably prone to rapid warming. Presence of resting cells, e.g. zygospores of Zygnemataceae and desmids, suggests that the pond may have dried periodically. Presence of Nuphar, Utricularia and Aldrovanda pollen, however, indicates long periods with standing water.

I analyzed spores, pollen and organicwalled algal remains in Middle Miocene deposits that filled a paleosinkhole at Tarno ´w Opolski, in the Upper Silesian Upland, Poland. Middle Triassic limestone bedrock in the study area underwent intense karstification under relatively warm and humid climate, resulting in development of numerous sinkholes. As the corrosion reached non-karstified marls, flowing water in the vadose zone was plugged and meteoric waters thus accumulated, leading to pond development. This palaeobotanical study was undertaken to ''reconstruct'' the fossil freshwater algae community and vegetation in and around the water body. Chlorophyta such as Botryococcus, filamentous algae from the family Zygnemataceae, mainly Mougeotia, Spirogyra and Zygnema, and desmids were important components of the algal assemblage. Most of the identified algae prefer mesotrophic to eutrophic conditions, and are characteristic of stagnant or slow-flowing shallow water. Among the free-floating and rooted plants were Salviniaceae/Azollaceae (probably Salvinia), Nuphar, Potamogeton, and carnivorous taxa such as Utricularia and probably Aldrovanda. The water body was surrounded by swamp vegetation composed of herbs such as Typha, Sparganium, Alismataceae and others, and riparian forests. The upper portion of the sediment section contains abundant pollen of swamp forest taxa such as Taxodium/Glyptostrobus, Nyssa and Alnus. The paleobotanical remains from the sinkhole at Tarno ´w Opolski suggest it was a shallow water body that was probably prone to rapid warming. Presence of resting cells, e.g. zygospores of Zygnemataceae and desmids, suggests that the pond may have dried periodically. Presence of Nuphar, Utricularia and Aldrovanda pollen, however, indicates long periods with standing water.

This pa per de scribes sedimentology and palynology of fresh wa ter plant-bear ing late Ce no zoic (Plio cene sensu lato) de posits drilled at Mizerna, the east ern part of the Nowy Targ Intramontane De pres sion, West Carpathians, southern Po land. Our data were ob tained from a newly-ana lysed 39 m thick suc ces sion from the Mizerna-Nowa bore hole, con tain ing spores, pollen and fresh wa ter or ganic-walled al gal mi cro-re mains. They shed light on the palaeoenvironmental con di tions of the Nowy Targ Intramontane De pres sion, where the Mizerna palaeolake once formed.

The Early Cretaceous Sarmord Formation of northern Iraq has been studied from two subsurface sections, Kirkuk Oil Field (well K-229) and Khabbaz Oil Field (well KH-14), through petrographic, palynolofacies and organic geochemical analyses. The study reveals presence of two groups of microfacies settings. The first is the inner ramp, and the second represents the middle to outer ramp setting. The palynofacies study indicates that the amorphous organic matter is the predominant components (87-96%), followed by phytoclasts (3-11%) and palynomorphs (0-3 %). One main palynofacies type has been identified, which includes three secondary palynofacies types (PF1 A, PF1B, and PF1C) and refers to suboxic to anoxic basin condition. Thermal alteration index measured for the KH-14 well, indicated an immature to mature (TAI= 2, +2, 3) level, while, for the K-229 well mostly immature (TAI= -2, 2). The Rock-Eval analysis indicates that the TOC wt.% content of the samples range between 0.11% and 0.8...

Several organisms or interaction of organisms have been described over a long time interval from the Late Palaeozoic to Cretaceous as Tubiphytes, with the type species being T. obscurus MASLOV, 1956. Palaeozoic Tubiphytes were revised by SENOWBARI-DARYAN & FLÜGEL (1993). Triassic representatives still need to be revised. For Jurassic (extremely abundant in upper Jurassic) and Cretaceous organisms, known as “Tubiphytes” morronensis CRESCENTI, 1969, we propose here the genus name Crescentiella. Differences between Crescentiella nov. gen. and Tubiphytes MASLOV are discussed. The systematic position of Crescentiella as a foraminifera, interaction of foraminifera and cyanophyceans or as a special kind of oncolite is discussed. It is interpreted as symbiosis or encrustation between cyanobacteria and a nubecularid foraminifera, uncertain tube or rarely, other biogenic components. Comments on similar associations, e.g. the genus Labes ELIASOVA, are provided.

Then, in the Cretaceous, and primarily in the Cenozoic, tectonic discontinuities filled with neptunian dykes were penetrated by karst waters and by hydrothermal solutions, which partly silicified the carbonate material infilling the dykes. The formation of dykes is genetically related to the Late Jurassic, Pan-European stress-field reorganization caused by the opening of the Northern Atlantic and Tethys Oceans.

The major constituent of Upper Jurassic limestones which build Brama Bolechowicka (Bolechowice Gate, a group o f valley-wall limestone rocks near Kraków) is massive limestone representing a complex of cyanobacterial-sponge carbonate buildups. Talus sediments of the buildup are present as clastic limestones exposed in isolated crags. Apparent bedding planes visible in the massive limestones are dissolution-widened fractures, fault joints and gently inclined shearing fractures in fault-related flexures. Limestones exposed ESE from Brama Bolechowicka represent interbiohermal facies and clastic sediments of variable age and origin. The Jurassic strata exposed ESE from Brama Bolechowicka lie within a wide fault zone which separates the Ojców Block from the Krzeszowice Graben. The variable dipping directions of these strata are caused mainly by the presence of hinge faults within this fault zone. A bstrakt. Zasadniczą część górnojurajskich wapieni tworzących Bramę Bolechowicką stanowi kompleks cyjanobakteryjno-gąbkowych budowli węglanowych wykształconych jako wapienie masywne. Osady talusa budowli są reprezentowane przez wapienie detrytyczne budujące pojedyncze skałki Bramy Bolechowickiej. Powierzchnie nieciągłości w wapieniach masywnych są spękaniami ciosowymi, szczelinami uskokowymi i połogimi ścięciami tektonicznymi w obrębie fleksury przyuskokowej. Osady odsłaniające się na ESE od Bramy Bolechowickiej reprezentują facje międzybiohermalne oraz osady detrytyczne o zróżnicowanym wieku i genezie. Występowanie na ESE od Bramy Bolechowickiej utworów jurajskich o zróżnicowanym wykształceniu, ale generalnie młodszych od facji obserwowanych w Dolinie Bolechowickiej ma przyczyny tektoniczne, a nie sedymentacyjne. Zmienne kierunki nachyleń tych utworów są spowodowane głównie obecnością uskoków zawiasowych w rozleglej strefie uskokowej oddzielającej płytę ojcowską od rowu krzeszowickiego.

eruption was probably the largest on Mt. Etna for 300 years. Since then the volcano has entered an unusually quiescent period. A comprehensive record of gravity and ground deformation changes presented here bracket this eruption and give valuable insight into magma movements before, during and after the eruption. The gravity and deformation changes observed before the eruption (1990)(1991) record the intrusion of magma into the summit feeder and the SSE-trending fracture system which had recent-

Dra matic tec tonic and sea level changes of the Cen tral Paratethys realm dur ing the Middle Mio cene re sulted in changes of the coastal and sea bed mor phol ogy af fect ing the com po si tion of the ma rine as so ci a tion and the dis tri bu tion of the fa cies along the coast. Three dif fer ent ep i sodes (ma rine-ter res trial-ma rine) in the en vi ron men tal evo lu tion are in ter preted. A lower ma rine unit (Badenian; Lower Serravallian) re flects organodetrital sed i men ta tion on and around an al gal bioherm. Low terrigenous in put maërl fa cies of typ i cal rhodalgal car bon ate fac tory type char ac ter ise the top of the al gal mound. On the slopes, a rim of rhodechfor fa cies sep a rated the bioherm from the rest of the bot tom which had a sea grass cover. This high-en ergy rhodechfor car bon ate fac tory is de scribed from the Cen tral Paratethys realm for the first time. It is com posed mostly of coralline al gae (Mesophyllum, Lithothamnion, Spongites and Lithophyllum), ben thic foraminifers (Elphidium crispum, Neoconorbina terquemi, Miniacina sp., Borelis melo), echinoids (cidaroid, spatangoid and diadematoid groups) and bryo zoans. Up lift of the Malé Karpaty Mts. re sulted in tec tonic ac tiv ity in the vi cin ity, doc u mented by the pres ence of clastic dikes and nor mal faults in the pro file stud ied. Sub se quent flu vial and ter res trial sed i men ta tion is rep re sented by regolith, palaeosoil and chan nel body de pos its set dis cor dantly on the top of la goonal de pos its. Fi nally, the third ep i sode is rep re sented by the Sarmatian transgressive ma rine se quence, which is characterized by coarse peb bly de posit eroded from an up lifted pre-Neo gene base ment. The strata stud ied orig i nated in a warm tem per ate cli mate around the Badenian-Sarmatian tran si tion.

Los autores desean rendir homenaje a quien por muchos años nos ha brindado su “don de gentes” como un ente de conexión entre colegas, haciendo con ello parte de su actividad profesional y adicionando a su cotidianidad la actividad gremial a través de la Sociedad Venezolana de Geólogos.

The Younger Dryas interval (YD) was a 9 period of widespread, abrupt climate change that 10 occurred between 12,900 and 11,700 cal yr BP 11 (10,900-10,000 14 C BP). Many sites in the Northern 12 Hemisphere preserve a sedimentary record across the 13 onset of the YD interval, including sites investigated 14 in sedimentary basins located in central Mexico 15 (Chapala, Cuitzeo, Acambay), the Basin of Mexico 16 (Tocuila), and northern Mexico (El Cedral). Deposits 17 consist of lacustrine or marginal lake sediments that 18 were deposited during the Pleistocene and the 19 Holocene. At the Tocuila and Acambay sites, Pleis-20 tocene fossil vertebrate assemblages, mainly mam-21 moths (Mammuthus columbi), are found in association 22 with a distinctive organic layer, sometimes called the 23 black mat that formed during the YD. At the Chapala, 24 Cuitzeo, Acambay, and Tocuila sites the black mats contain a suite of distinctive microscopic and mineralogical signatures and are accompanied by a sharp change in the depositional environments as supported by diatom and pollen studies reported here. The signatures include magnetic, Fe-rich microspherules, silica melted droplets with aerodynamic shapes (tektites), large amounts of charcoal, and sometimes nanodiamonds (Cuitzeo), all of which were deposited at the onset of the YD. The geochemistry of the microspherules indicates that they are not anthropogenic, authigenic or of cosmic or volcanic origin, and instead, were produced by melting and quenching of terrestrial sediments. Here, we present the stratigraphy at five field sites, the analyses of magnetic microspherules, including major element composition and scanning electron microscopy images. All of these materials are associated with charcoal and soot, which

Punta Licosa Promontory, located in southern Campania (Tyrrhenian Sea, Southern Italy), lies between
Castellabate Plain and Ogliastro Bay. On land, the promontory features the San Mauro and Pollica formations
of the Flysch del Cilento unit (Aiello & Caccavale, 2024), dating from the Early Tortonian to Langhian.
Offshore, it extends into the sea, where Quaternary heterogeneous deposits overlay well-bedded arenaceous
flysch. Notably, the submerged portion includes several submarine terraces at depths between 8 and 100 meters
(Savini et al., 2021), interpreted as remnants of the Upper Pleistocene, or shaped by the Last Glacial Maximum
(LGM) regression and subsequent post-glacial sea-level rise.
A 2004 survey identified previously unknown beehive-like morphological structures on one such submerged
terrace around 100 m of water depth. Only a few grab samples were collected at that time, leading to a
preliminary hypothesis of a biogenic origin (Bracchi, unpublished thesis), in need of further investigation.
The CORSUB project, funded under the Italian PRIN 2022 program, adopts an interdisciplinary approach,
integrating geophysical, stratigraphic, sedimentological, and paleontological methods, to explore these
formations’ origins, evolution, and ecological significance.
During the CORSUB-1 (06/2024) and TREMOR (12/2024) cruises, the team collected high-resolution
data, including side-scan sonar, multibeam bathymetry, sub-bottom profiles, and box-corer sediment samples.
The observed features consist of clusters of sub-circular to polygonal weakly convex structures between 78
and 83 m, each less than one meter in diameter and rising less than 50 cm at their centers. Interestingly, the
central portions exhibit lower acoustic reflectivity than their surrounding edges. Chirp profiles reveal a thin
sedimentary layer overlying a rocky substrate, likely part of the Cilento Flysch. Box-corer samples indicate a
stratified sub-seafloor, with coarse biogenic sand and gravel at the surface transitioning to gravelly sand with
varying mud content below. Notably, all samples contain dead, centimeter-sized boxwork rhodoliths, buried
8–20 cm beneath the seafloor. Only one sample yielded live rhodoliths undergoing intense muddying.
Based on these results, the hypothesis that these structures could have a biogenic origin stands, potentially
linked to past rhodolith bed development during slow phases of Holocene sea-level rise. Alternatively, they
may be erosional remnants from glacial and post-glacial sea-level fluctuations, initially forming during the
LGM when the studied areas were exposed and later serving as a substrate for biological colonization during
the deglaciation and post-LGM transgression.
Further remote and direct analyses, including absolute dating, are underway to clarify the nature and
evolution of these intriguing submarine features.

9th EPPC Padova 2014 Arabian Plate sequence stratigraphy of the Cambrian to early Silurian interval After Sharland et al. (2001) and correlation with coeval succession of North Africa Phanerozoic cycles of sea-level change on the Arabian Platform

This paper presents the key findings of a multidisciplinary study investigating the nature and timing of coastal landscape evolution in eastern Saudi Arabia during the Holocene. To date, most sea level reconstructions for the Arabo-Persian Gulf are based on uncalibrated 14 C ages without correction for marine reservoir effects, or lack precision with regard to the effects of neotectonic changes, indicators of sea level used, errors in elevation of sedimentary units used, and the relationship with actual tides. As a consequence, the nature and timing of relative sea level (RSL) changes during the Late Pleistocene and Holocene remain poorly understood. To help address this, we use sea level index points (SLIPs) based on calibrated 14 C ages to present a RSL curve for the central-southern Gulf of Saudi Arabia from coastal sabkha deposits near the archaeological site of Dosariyah. The sediments record rapid transgression during the early Holocene with a mid-Holocene high-stand immediately prior to 6880-6560 cal. BP when the upper limit for the palaeo Mean Highest High tide water (MHHW) was 2.8-3.10 m above present day mean sea level. Transgression continued until shortly after 5575-5310 cal. BP with an upper limit to the palaeo-MHHW of 3.75 m above present sea levels. Thereafter a fall in RSL was recorded, with the regression leading to the progradation of the coastal system and the development of coastal sabkhas. Nonetheless later transgressions are recorded in the region between 4848-4536 and 4335-3949 cal BP. Radiometric dating results from archaeological excavations at Dosariyah, one of the most important Neolithic coastal sites in the Gulf, suggest that occupation of the site during the Neolithic coincides with the mid-Holocene marine transgression (ca. 7200 -6500 cal. BP). Whilst the close proximity of the site to the sea may have facilitated maritime exchange activities, occupation of the site was short-lived and the phase of abandonment occurred during a period of rapid RSL rise, which would have transformed the area around Dosariyah into an island or certainly cut it off tidally from the mainland.

ABSTRACTThis study investigates hydrological responses to climatic shifts using sediment flux data derived from two dated palaeolake records in south‐east Arabia. Flux values are generally low during the early Holocene humid period (EHHP) (∼9.0–6.4k cal a BP) although several short‐lived pulses of increased detrital input are recorded, the most prominent of which is dated between ∼8.3 and 7.9k cal a BP. The EHHP is separated from the mid‐Holocene humid period (MHHP) (∼5.0–4.3k cal a BP) by a phase of increased sediment flux and aridity, which began between ∼6.4 and 5.9k cal a BP and peaked between ∼5.2 and 5.0k cal a BP. The termination of the MHHP is marked by a phase of high detrital sediment flux between ∼4.3 and 3.9k cal a BP. While long‐term shifts in climate are most likely linked to changes in the summer position of the Intertropical Convergence Zone and associated Indian and African monsoon systems, it is noted that the abrupt, short‐term phases of aridity observed in both r...

Hyperpycnal flows have been widely described in different lacustrine and marine environments but sedimentary structures and fossil content in hyperpycnites often offer limited information about the palaeoenvironmental conditions. This limitation can be improved by ichnological analysis, which has been recently used as a tool to differentiate between different type of subaqueous deposits, even though still only a few detailed ichnological studies on hyperpycnites exist. In order to bridge this gap in knowledge, a 50 m-thick package of terrestrial organic debris-rich, dominantly structureless and well-sorted sandstone bodies alternating with burrowed siltstones (Upper Miocene, Betic Cordillera, Spain) is here analyzed. This study is based on observations of a wellexposed outcrop and cores from a well drilled just behind the outcrop to bridge field-scale observational gaps. Two type of sandbodies were typified on the basis of their stratigraphic architecture, physical sedimentary structures, and ichnofacies in the fine-grained deposits embedding them: (1) Lobate to channelized-top sandstones embebbed into silty sands with dominant highly variable degree of bioturbation by Taenidium and Schaubcylindrichnus (depauperate Cruziana ichnofacies) and interpreted as proximal marine sustained hyperpycnites in prodelta settings; and (2) channelized-lobate (cut-and-fill sequence) sandstones embebbed into siltstones with dominant Nereites and Phycosiphon (Nereites ichnofacies) interpreted as distal hyperpycnites developed in offshore settings. The studied succession is interpreted to represent the progradation of a sandy hyperpycnal system along a prodelta to starved offshore setting with high variability in grain-size, benthic food and oxygen content. Results of this study suggest that a multi-scale analysis focused on trace fossils and physical sedimentary signatures is needed to get a better understanding of these river-derived sustained-flow turbidites (hyperpycnites) that are less well known than their conventional surge-type turbidite counterparts.

The physical volcanology of widespread rhyolites and dacites overlying flood basalt lavas in the northwestern and northern parts of the 65.5-Ma Deccan Traps, India, is poorly known. We show that these are not lava flows but high-grade (welded and rheomorphic) to extremely high-grade (lava-like) ignimbrites deposited by pyroclastic density currents. Evidence for this interpretation includes the following: (i) flat, planar contacts with the underlying basalts and absence of basal brecciated zones; (ii) pervasive millimeter-tocentimeter-scale flow banding; (iii) parataxitic textures indicating very high degrees of compaction and welding; (iv) strong rheomorphic deformation, producing folds of diverse geometries and sizes showing overprinting relationships, with common tight-isoclinal and sheath (eye) folds that are sometimes refolded into F 2 and even F 3 folds; (v) curvilinear fold hinges with elongation lineations varying from transverse to subparallel to the fold axes; (vi) local boudinage and autobrecciation in flow-banded glassy tuffs; (vii) common and abundant spherulites and lithophysae; (viii) intimate association of tuff and vitrophyre at millimeter to tens-of-meter scales; and (ix) vitroclastic textures showing highly flattened and stretched glass shards and pumice fiamme wrapping around phenocrysts. Whereas rheomorphic and lava-like ignimbrites dominate, some non-welded and welded (eutaxitic) ignimbrites also occur. Voluminous rhyolites and dacites in many flood basalt provinces of the world are recognized as high-grade to extremely high-grade ignimbrites, and the Deccan is no exception. This Deccan explosive silicic volcanism may have significantly contributed to the K/Pg boundary mass extinctions, if contemporaneity can be established by future geochronological work.

Icebergs plough through unconsolidated lake/sea sediments gouging out kilometre long grooves, 100s of metres wide and tens of metres deep. Although the surface morphology of iceberg scours is well documented, little is known about what scours look like in stratigraphic section, particularly where surface characteristics are absent (e.g. through deterioration or burial). This is exacerbated by their inaccessibility in modern

L'estudi de diversos descriptors paleoambientals com ara el pol·len, les diatomees i la sedimentologia, realitzat en sedi-ments procedents del llac de Sanabria (NO de la península Ibè-rica), ha aportat informació sobre les oscil·lacions climàtiques atribuïdes als períodes ...

The Rakhine‐Bangladesh megathrust, also known as the Sumatra-Andaman Trench, is thought to be connected to the Kaladan Fault based on seismic sections, sedimentological, and stratigraphic data. However, during the Miocene, this shallow megathrust, situated within an ocean-continent subduction zone, did not exhibit typical oceanic or subduction-related characteristics, and its nature could not be determined solely through sedimentological analysis. There is no clear evidence that adequately explains the origin or implications of this feature, even under the assumption that the Indian Plate is subducting obliquely beneath the overriding Burma Plate. The application of the Kabaw Fault hypothesis by Oryan et al. (2023) warrants reconsideration, given the lack of supporting geological evidence, including seismic and structural data. Similarly, the hypothesis proposed by Mallick et al. (2020), suggesting the initiation of northward subduction of the Surma Basin beneath the Shillong Massif due to north–south compression or shortening, remains highly questionable due to insufficient evidence. The absence of historical megathrust earthquakes further challenges the appropriateness of the term "Rakhine‐Bangladesh megathrust." The mere presence of anticlines, as observed above the Hikurangi, Alaska, and Cascadia megathrusts, does not constitute sufficient evidence for the existence of a megathrust responsible for anticline formation in this region.

HAL is a multi-disciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

The results of investigations in 2006–2010 for hydrocarbon and gas hydrates on the Antarctic Peninsula continental margin are given. In 2004 and 2006, the marine geoelectric researches by methods of forming a short-pulsed electromagnetic field (FSPEF) and vertical electric-resonance sounding (VERS) had been conducted in this region. The “deposit” type anomaly was mapped by FSPEF survey, and anomalous polarized layers of “hydrocarbon deposit” type were chosen by VERS sounding within this anomaly on Antarctic margin in the region of UAS “Academician Vernadsky.” Anomalous zones of “gas hydrate deposit” type were detected on the South Shetland margin due to the special technology of satellite data processing and interpretation using. These results confirm the high gas hydrates potential of the West Antarctica region. Some practical results of the experimental approbation of these original technologies for the “direct” prospecting and exploration of hydrocarbon (HC) and gas hydrates accu...

The aim of this study was to establish a sequence stratigraphic framework for the Upper Cretaceous (Albian to Santonian) sedimentary rocks of South Jordan. This was accomplished by detailed sedimentological studies and facies analysis. Furthermore the provenance and weathering history of the siliciclastic rocks was determined by using sedimentary petrography and bulk rock geochemistry. The study area is situated in the southern part of Jordan, about 60 km south of the city Ma’an, between the city Ras en Naqb in the West to Naqb Ataik in the East. Here a succession of Palaeozoic to Cretaceous sedimentary rocks is exposed along a NW-SE to E trending, about 90 km long escarpment. Along this escarpment fifteen vertical sections were logged in detail and samples where taken in the Cretaceous deposits. On the basis of these logs the facies analysis and sequence stratigraphic interpretation was carried out. Selected samples were used for petrographical and geochemical studies. Facies analy...

We question the biogenicity of putative bacterial and cyanobacterial 'microfossils' from 3465 Ma Apex cherts of the Warrawoona Group in Western Australia. They are challenged on the basis of integrated multidisciplinary evidence obtained from field and fabric mapping plus new high-resolution research into their context, sedimentology, filament morphology, 'septation' and arrangement. They cannot be distinguished from (and are reinterpreted as) secondary artefacts of amorphous carbon that formed during devitrification of successive generations of carbonaceous hydrothermal dyke vein quartz. Similar structures occur within associated carbonaceous volcanic glass. The null hypothesis of an abiotic or prebiotic origin for such ancient carbonaceous matter is sustained until mutually supporting contextural, morphological and geochemical evidence for a bacterial rather than abiotic origin is forthcoming.

5.68 ‰) confirm the mantle origin of the carbon for these rocks. The origin of Catalão II cumulitic rocks is thought to be caused by differential settling of the heavy phases (magnetite, apatite, pyrochlore and sulphides) in a magma chamber repeatedly filled by carbonatitic/ferrocarbonatitic liquids (s.l.). The Sr-Nd isotopic composition of the Catalão II rocks matches those of APIP rocks and is markedly different from the isotopic features of alkaline-carbonatitic complexes in the southernmost Brazil. The differences are also observed in the lithologies and the magmatic affinity of the igneous rocks found in the two areas, thus demonstrating the existence of regional-scale heterogeneity in the mantle sources underneath the Brazilian platform.

Dating techniques based on the natural and anthropogenic radionuclides 210 Pb and 137 Cs were applied to the study of the sedimentation regime in Cienfuegos Bay, Cuba. Core samples were collected from different locations in the bay and analyzed to evaluate the accumulation rate, through the 210 Pb dating technique. Results evidenced significant changes in the sedimentation rate during the last forty years: the recent sediment accumulation rates (0.40-0.45 g•cm -2 •yr -1 ) are almost double those estimated before 1965 (0.15-0.20 g•cm -2 •yr -1 ). The 210 Pb profiles show significant deviations from a simple exponential decline and abrupt variations between 1966-1970 and 1985-1990. These irregularities match closely periods of changes in land use (regimentation of the Arimao and Caonao rivers in the late 1960s and early 1970s) and exceptional natural events (Hurricane Camille in 1969 and the intense rainfall of 1988) which occurred in Cienfuegos. The 137 Cs and chlorite minerals profiles validate the results obtained from 210 Pb dating and confirm the effect of exceptional events and changes in the natural hydrological regime of the bay during the past forty years.

The Sava depression and the Bjelovar subdepression belong to the SW margin of the Pannonian Basin System. This area was a part of the Central Paratethys during Late Pannonian period. Geotectonically the Bjelovar subdepression represents a submarine slope between the Sava and Drava depressions. In the Sava depression analyzed Late Pannonian deposits include several lithostratigraphic members: Iva and Okoli sandstones (or their lateral equivalent Zagreb member), as well as the Lipovac marlstone. Sandstone members are proved as economical hydrocarbon reservoirs. Generally, entire Late Pannonian sequence is lithologically represented by alterations of marls, silts and sandstones. Total thickness of these sediments in the deepest part reaches up to 800 meters, and along depression margins from 100-200 meters. Deposits are compound of 4 facies: • Facies of thick layered to massive sandstones (F1) sedimented in channels in the Donja Jelenska subdepression ; • Facies of thin sandstone layer...

Une méthode d'interprétation des données granulométriques a été proposée par 1964) afin de différencier les dépôts issus de différents modes de transport en milieu fluviatile et marin (suspension uniforme, suspension gradée, roulage). Elle consiste à utiliser deux centiles caractéristiques (D 99 et D 50 ) d'une courbe granulométrique d'un sédiment, à les reporter sur un graphique à double échelle logarithmique et à comparer la position du point avec un modèle (Image CM) déterminé sur la base d'échantillons prélevés dans des dépôts pour lesquels les conditions de mise en place sont connues. Plusieurs études ont montré que cette méthode permettait également de différencier les faciès sédimentaires en fonction des caractéristiques granulométriques des sédiments qui s'y déposent et donc de déterminer a posteriori les conditions de sédimentation et de transport des alluvions anciennes. Toutefois, de nombreux paramètres spécifiques à chaque cours d'eau influencent les caractéristiques de l'Image CM et il n'existe pas d'Image universelle transposable à tous les environnements fluviatiles . Cet article présente une dizaine d'Images CM de rivières ardennaises, obtenues sur la base d'échantillons prélevés dans des dépôts mis en place dans des conditions hydrodynamiques connues et pour lesquels le mode de mise en place pouvait être reconstitué. Le but de cet article est donc de fournir un outil fiable pour proposer des interprétations solides sur les conditions de sédimentation des dépôts fluviatiles anciens des rivières ardennaises et, d'une manière plus générale, de rivières de basses montagnes (ω = 15 à 150 W/m²) à lit caillouteux (Eifel, Vosges, Morvan …).

Gravel size sediment beds are tested under the combined influence of simulated wave action and co-linear currents in a laboratory flume. Critical current speed, at threshold, increases with increasing size. Superimposed wave energy causes a small reduction in the unidirectional current energy. For low values of wave-induced near bed current velocities, the resistance to erosion increases when the wave period decreases from 10 to 6 s. Finally, combined critical shear stresses are found to be lower than those predicted using the Shields curve, as modified for oscillatory flow. Grain protrusion is suggested as a mechanism to explain this divergence. *A full and detailed description of the experimental equipment used in the present study is presented in Tomlinson (1993).