Did an earthquake located off Jersey trigger a mudflow preserving the only loess outcrop known under the seas?

2020 ◽  
Vol 177 (5) ◽  
pp. 911-922
Author(s):  
Jean-Pierre Lefort ◽  
Paul Chambers ◽  
Guzel Danukalova ◽  
Jean-Laurent Monnier ◽  
Eugenia Osipova ◽  
...  
Keyword(s):  
Slope Failure ◽  
Core Sample ◽  
Seismic Zone ◽  
Content Type ◽  
The Core ◽  
Loess Deposit ◽  
Mollusc Species ◽  
Supplementary Material ◽  
Rule Out

A 5 m long core sample, retrieved from between Jersey and the Cotentin (France) has been studied using different techniques. Between the lower part and the top, the core is a yellowish loess, a black mud and a grey shelly formation. The basal formation, which displays a typical loess granulometry, is the only loess found anywhere in situ on the subtidal seabed worldwide. Elsewhere, this fragile sediment has always been washed out by the successive Quaternary transgressions. The overlying mud formation, which displays characteristics of a landslide, sealed the loess deposit. Because this core has been sampled on the rim of a submarine valley located in front of a major onshore geological disruption, clearly associated with an active seismic zone, it is possible that an earthquake triggered a slope failure causing a gravity collapse of materials that protected the loess deposit from subsequent erosion, although we cannot completely rule out the effects of a large flood.Supplementary material: Tables showing the results of the pollen analysis and distribution of mollusc shells and other fossils in borehole O-VC15, and a figure showing the distribution of mollusc species in core O-VC15 and a possible reconstruction of the palaeoenvironment during sediment deposition are available at https://doi.org/10.6084/m9.figshare.c.4991753

Geochemical evaluation of the in-situ regolith of Madengi hills of Dodoma, Tanzania. Implication on bedrock mapping and delineating gold mineralization target

2021 ◽  
pp. geochem2021-074
Author(s):  
Godson Godfray
Keyword(s):  
Gold Mineralization ◽  
Early Stage ◽  
Shear Zones ◽  
Soil Geochemistry ◽  
Residual Soils ◽  
Content Type ◽  
Geochemical Evaluation ◽  
Supplementary Material ◽  
Pathfinder Elements

Successful gold exploration projects depend on a piece of clear information on the association between gold, trace elements, and mineralization controlling factors. The use of soil geochemistry has been an important tool in pinpointing exploration targets during the early stage of exploration. This study aimed to establish the gold distribution, the elemental association between gold and its pathfinder elements such as Cu, Zn, Ag, Ni, Co, Mn, Fe, Cd, V, Cr, Ti, Sc, In, and Se and identify lithologies contributing to the overlying residual soils. From cluster analysis, a high similarity level of 53.93% has been shown with Ag, Cd, and Se at a distance level of 0.92. Au and Se have a similarity level of 65.87% and a distance level of 0.68, hence is proposed to be the most promising pathfinder element. PCA, FA, and the Pearson's correlation matrix of transformed data of V, Cu, Ni, Fe, Mn, Cr, and Co and a stronger correlation between Pb and U, Th, Na, K, Sn, Y, Ta and Be shows that source gold mineralization might be associated with both hornblende gneisses interlayered with quartzite, tonalite, and tonalitic orthogneiss. From the contour map and gridded map of Au and its pathfinder elements, it has been noted that their anomalies and target generated are localized in the Northern part of the area. The targets trend ESE to WNW nearly parallel to the shear zones as a controlling factor of Au mineralization emplacement.Supplementary material:https://doi.org/10.6084/m9.figshare.c.5721965

scholarly journals Seasonal dynamics of Daphnia laevisBirge, 1878 ephippia in a tropical lake with a description of a new methodology for in situ evaluation

2014 ◽  
Vol 74 (3) ◽  
pp. 642-648 ◽  
Author(s):  
LPM Brandão ◽  
DGF Pujoni ◽  
PM Maia-Barbosa
Keyword(s):  
Water Column ◽  
Seasonal Dynamics ◽  
Thermal Stratification ◽  
Core Sample ◽  
Hatching Rate ◽  
The Core ◽  
Significant Difference ◽  
Chi Squared ◽  
Hatching Rates

The effect of dormancy in zooplankton populations is still unknown, largely because of the lack of methods to estimate hatching and production of the dormant stages. This study aimed to compare the production and hatching rates of ephippia of Daphnia laevis between thermal stratification and mixing periods in Jacaré Lake (Middle Rio Doce, Minas Gerais, Brazil). For this, we collected ephippia on the sediment with core sampler and we created a device called the “Ephippial Collector”. There was a significant difference in ephippia hatching in situ between stratification and mixing periods (Pearson's Chi-squared test p <0.001), being higher in the second one. Significant differences in the hatching rates between periods was observed in the laboratory only for ephippia collected with Ephippial Collectors (Pearson's Chi-squared test p <0.001), being higher during the mixing period (∼8%). The core sample allows the collection of a certain fraction of the sediment that may contain a mixture of ephippia produced in different periods, i.e., may contain old and not viable ephippia, which masks the hatching rate. Thus, seasonality in hatching rates of ephippia was reported only by Ephippial Collectors. The higher hatching rate observed during the mixing period in the lake suggests that individuals hatched from ephippia may contribute to the increase in the population of D. laevis in the water column at this time.

Primary versus carbonate production in the Toarcian, a case study from the Llanbedr borehole (Mochras Farm, Wales)

2021 ◽  
pp. SP514-2021-19
Author(s):  
Alessandro Menini ◽  
Emanuela Mattioli ◽  
Stephen P. Hesselbo ◽  
Micha Ruhl ◽  
Guillaume Suan
Keyword(s):  
Sea Water ◽  
Initial Perturbation ◽  
Carbonate Production ◽  
Nutrient Delivery ◽  
Content Type ◽  
High Productivity ◽  
Oceanic Anoxic Event ◽  
The Core ◽  
C Isotopes ◽  
Supplementary Material

AbstractThe leading hypothesis for the Toarcian oceanic anoxic event (T-OAE; ∼183Ma) and the associated negative C-isotope excursion is the massive release of 12C favouring greenhouse and continental weathering. The nutrient delivery to shallow-basins supported productivity and, because of O2-consumption by organic-matter respiration, anoxia development. However, several works showed that calcareous nannoplankton experienced a decrease during the T-OAE. Nannofossil fluxes measured in the Llanbedr borehole (Mochras Farm; Wales, UK) were the highest prior to the negative C-isotope excursion, along with high amounts of taxa indicative of nutrient-rich environments (Biscutaceae). Such conditions attest to high productivity. Fluxes show the lowest values in the core of the event, along with a size decrease of Schizosphaerella and a peak in Calyculaceae. The recovery of nannofossil fluxes and Schizosphaerella size occurred concomitant with the return of C-isotopes to more positive values. Concomitantly, deep-dwellers (Crepidolithus crassus) dominated, indicating a recovery of the photic-zone productivity. These observations demonstrate that the cascade of environmental responses to the initial perturbation was more complex than previously considered. In spite of elevated nutrient delivery to epicontinental basins in the early Toarcian, carbonate and primary productions of nannoplankton were depressed in the core the T-OAE likely because of prolonged thermohaline sea-water stratification.Supplementary material at https://doi.org/10.6084/m9.figshare.c.5541440

Phosphate diagenesis of carbonate sediments as a mode of in situ formation of marine phosphorites: Observations in a core from the eastern Pacific

1968 ◽  
Vol 5 (1) ◽  
pp. 81-87 ◽  
Author(s):  
Bruno F. d'Anglejan
Keyword(s):  
Core Sample ◽  
Ion Concentration ◽  
Soluble Phosphate ◽  
Carbonate Sediments ◽  
The Core ◽  
Carbonate Ion ◽  
Carbonate Fluorapatite ◽  
In Situ Formation ◽  
Common Association

Carbonate-fluorapatite, the mineral of marine phosphorite, is found to form contemporaneously within the sediments by the replacement of skeletal carbonate in a core sample of foraminiferal ooze from the eastern tropical Pacific. A systematic downward increase in apatite within the core suggests that replacement is continuing at a decreasing rate in the sediments. The widespread distribution of foraminiferal ooze on the California borderland and its common association with phosphorite suggest that this material may play a role in the phosphorite accumulation there. The reaction of CaCO3 with soluble phosphate in conditions favoring the slow dissolution of the carbonate mineral may result within the sediments in an increase of the carbonate ion concentration, which appears to control the rate of replacement.

scholarly journals Geomechanical Characteristics And Failure Analysis of The Limestone Slope At Sahastradhara-Chamasari Road Dehradun Uttarakhand India

2021 ◽  
Author(s):  
Nirlipta Priyadarshini Nayak ◽  
Harinandan Kumar ◽  
Ashish Aggarwal ◽  
Muralidhar Singh M.
Keyword(s):  
Compressive Strength ◽  
Internal Friction ◽  
Failure Analysis ◽  
Slope Failure ◽  
Axial Strain ◽  
Core Sample ◽  
Loading Conditions ◽  
Angle Of Internal Friction ◽  
The Core ◽  
Limestone Rock

Abstract In this study, the rock slope failure analysis was carried out to predict the stability of the limestone rock in the Sahastradhara-Chamasari Road Dehradun Uttarakhand, India. The limestone rock samples were collected from the study area for testing purposes. The geomechanical parameters like compressive strength, axial strain, young’s modulus, cohesive strength, angle of internal friction, etc., were experimentally determined to study their application in the simulation of slope failure analysis. A 2D model of the study area was developed using the field data for modelling and simulation purposes. Slope failure analysis was carried out using the Finite element method (FEM). Results indicated maximum compressive strength of the core sample as 85.14 MPa while axial strain and elastic modulus were 0.02197 and 842.45 MPa, respectively. The cohesive strength and the angle of internal friction of the core sample were evaluated as 38.59 kPa and 12.96 degree. The slope failure analysis was carried out to determine the factor of safety (FOS) of the slope at variable loading conditions. A decreasing trend of the FOS was observed with loading. The lesser value of FOS at higher loading conditions required the supporting system at the foot level of the slope for the slope stability in the study area.

In-situ laser ablation Lu–Hf geochronology of garnet across the Western Gneiss Region: Campaign-style dating of metamorphism

2021 ◽  
pp. jgs2021-094
Author(s):  
Renée Tamblyn ◽  
Martin Hand ◽  
Alexander Simpson ◽  
Sarah Gilbert ◽  
Ben Wade ◽  
...  
Keyword(s):  
Laser Ablation ◽  
Ultrahigh Pressure ◽  
Western Gneiss Region ◽  
Content Type ◽  
Link Type ◽  
Geological Processes ◽  
History Of ◽  
Supplementary Material ◽  
Wilson Cycle

The development of in-situ laser ablation Lu–Hf geochronology of apatite, xenotime and garnet has opened avenues to quickly and directly date geological processes. We demonstrate the first use of campaign-style in-situ Lu–Hf geochronology of garnet across the high- to ultrahigh-pressure Western Gneiss Region in Norway. Mafic eclogites from this region have been the focus of much work, and were clearly formed during continental subduction during the Caledonian Orogen. However, abundant quartzofeldspathic and pelitic lithologies record a more complex history, with some preserving polymetamorphic age data, and most containing no indication of high-pressure mineral assemblages formed during subduction. Twenty metapelitic and felsic samples spanning 160 lateral kilometers across the Western Gneiss Region have been analysed using garnet Lu–Hf geochronology. The results reveal Caledonian ages for the majority of the garnets, suggesting some quartzofeldspathic and metapelitic lithologies were reactive and grew garnet during high- to ultrahigh-pressure metamorphism. However, two ultrahigh-pressure eclogite locations, Verpeneset and Fjørtoft, preserve both Caledonian and Neoproterozoic-aged garnets. Despite significant uncertainties on some of the Lu–Hf geochronologic ages, laser ablation Lu–Hf efficiently identifies the polymetamorphic history of parts of the Western Gneiss Region, illustrating the effectiveness of this novel analytical method for rapid mapping of metamorphic ages.Thematic collection: This article is part of the Caledonian Wilson cycle collection available at: https://www.lyellcollection.org/cc/caledonian-wilson-cycleSupplementary material:https://doi.org/10.6084/m9.figshare.c.5715453

scholarly journals Geochemistry of macrofossil, bulk rock, and secondary calcite in the Early Jurassic strata of the Llanbedr (Mochras Farm) drill core, Cardigan Bay Basin, Wales, UK.

2021 ◽  
pp. jgs2021-018
Author(s):  
Clemens V. Ullmann ◽  
Dominika Szűcs ◽  
Mengjie Jiang ◽  
Alexander J.L. Hudson ◽  
Stephen P. Hesselbo
Keyword(s):  
Sea Level ◽  
Carbon Isotope ◽  
Analytical Data ◽  
Early Jurassic ◽  
Sediment Provenance ◽  
Carbonate Content ◽  
Level Control ◽  
Content Type ◽  
The Core ◽  
Supplementary Material

The Llanbedr (Mochras Farm) core (Wales, United Kingdom) yielded a > 1,300 m long mudrock sequence which has excellent potential for establishing an integrated stratigraphic scheme for the entire Early Jurassic Epoch. Lithological variations in the core are predominantly driven by hierarchical changes in carbonate content which also dominate – or may impact upon – many geochemical and physical properties of the core. The bulk carbonate carbon isotope record displays systematic fluctuations the largest of which correspond to previously identified phases of environmental perturbation. The magnitudes of negative carbon isotope excursions in carbonate are inflated compared to equivalents previously described elsewhere due to diagenesis and concomitant loss of primary carbonate.The marine macrofossil record of Mochras reveals biological and isotopic patterns that are generally comparable to other UK basins. Potentially significant differences between Cleveland and Cardigan Bay Basin are observed in the Pliensbachian and Toarcian fossils. This different expression may be related to different habitat structure or palaeoceanographic and water depth differences between these basins. Minima in macrofossil δ18O values generally coincide with peaks in macrofossil wood abundance and sea-level lowstands inferred from sequence stratigraphic interpretation of other UK sections. This relationship points to a possible relative sea-level control on observed oxygen isotope records and sediment provenance.Supplementary material: Analytical data for the Mochras core pertaining to this contribution is available online at https://doi.org/10.6084/m9.figshare.c.5463508

Primary tissues dominated ground-level trunk diameter in Sigillaria: evidence from the Wuda Tuff, Inner Mongolia

2021 ◽  
pp. jgs2021-021
Author(s):  
Michael P. D'Antonio ◽  
C. Kevin Boyce ◽  
Wei-Ming Zhou ◽  
Hermann W. Pfefferkorn ◽  
Jun Wang
Keyword(s):  
Inner Mongolia ◽  
Ground Level ◽  
Early Ontogeny ◽  
Internal Anatomy ◽  
Living Plant ◽  
Content Type ◽  
Trunk Diameter ◽  
Primary Body ◽  
Supplementary Material

Arborescent lycopsid stumps are typically fossilized as casts, so that proximal anatomy is rarely available for study. This presents a roadblock for empirically reconstructing their early ontogeny, which requires knowledge of proximal tissue proportions. Here, we describe nine upright, in situ stump casts of Sigillaria from the earliest Permian Wuda Tuff, Inner Mongolia, China that preserve traces of internal anatomy. From these specimens, we interpret thin vasculature and periderm and a broad primary cortex within ∼50 cm of ground level in the living plant. These specimens support recent arguments that periderm production was limited in arborescent lycopsids and that the primary body reached its mature diameter close to ground level rather than distally further up the trunk.Supplementary material: additional figures of specimens and data regarding where measurements were made is available at https://doi.org/10.6084/m9.figshare.c.5558620

Capturing the transient hydrological response in sandy soils during a rare cloudburst associated with shallow slope failures—a case study in the Atlantic Highlands, New Jersey, USA.

2021 ◽  
pp. qjegh2020-127
Author(s):  
Francis X. Ashland ◽  
Pamela A. Reilly ◽  
Alex R. Fiore
Keyword(s):  
New York ◽  
New Jersey ◽  
Slope Failure ◽  
Shallow Landslide ◽  
Hydrological Response ◽  
Slope Failures ◽  
Content Type ◽  
Antecedent Moisture ◽  
Supplementary Material ◽  
Moisture Conditions

A cloudburst on August 7, 2018, in the coastal bluffs of the Atlantic Highlands, New Jersey induced flooding, erosion, and multiple shallow slope failures that adversely impacted the surrounding hillside residential area. Historically, short-duration deluges are rare in the New York Bay region, with only eight cloudbursts of greater magnitude documented since 1948. The coastal bluffs consist of a variably thick, sandy surficial material overlying flat lying, mostly non-indurated Cretaceous and Tertiary sediments, including some low permeability glauconitic units. The bluffs have been impacted by both historical deep-seated and shallow landslide movement, the latter typically related to heavy, relatively long-duration rainfall associated with tropical cyclones and nor'easters. The shallow hydrological response during the rare cloudburst was captured at two hydrological monitoring sites and yielded insights into rapidly changing moisture conditions resulting in slope failure. Additional information is provided on historical cloudbursts that have affected the region, antecedent moisture conditions, and documented landslide types and processes.Supplementary material: A USGS ScienceBase data release of the time-series monitoring data accompanies the publication of this paper https://doi.org/10.5066/P9A601HC.

Estudio del proceso de lavado de contenedores para eliminar tiempos y movimientos innecesarios, caso: Wash Containers S.A de C.V.

2020 ◽  
pp. 25-36
Author(s):  
Juan Alfredo Lino-Gamiño ◽  
Carlos Méndez-González ◽  
Eduardo José Salazar-Araujo ◽  
Pablo Adrián Magaña-Sánchez
Keyword(s):  
Business Process ◽  
Value Chain ◽  
Process Management ◽  
Core Business ◽  
The Core ◽  
Washing Process ◽  
Overall Performance ◽  
The Times

In the value chain it is important to keep in mind the core business of the company, since it depends largely on the competitiveness of the company and its overall performance, bearing in mind that all business indicators depend on it. In this work we will study the washing process within the company WASH CONTAINERS SA DE CV, to improve the washing processes and in this way reduce times and movements in the process leading the company to reduce costs considerably within the operations company daily, having a more competitive operation and with greater profit margin in its business process. Goals: It Improve the logistics of the movement of containers for washing and with it the core business of the company. Methodology: The action research will be applied applying Business Process Management for the improvement of processes in situ, it will be developed in a certain period of time and with that it will establish an improvement projection. Contribution: The improvement of the times for the disposal of the containers and their subsequent use, allows a better competitiveness and with it the income of the company, on the other hand, the transport companies improve in performance in quantity, quality of disposition and with it their income.

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