Search

The Silurian Coralliferous Formation of Pembrokeshire comprises 94–143 m of shelfal sediments deposited on the southern margin of the Welsh Basin, UK. The succession begins with rudites (Renney Slip Member), which are overlain by interbedded silty mudstone and sandstone (Deadman's Bay Member). Biostratigraphical control is weak between the two principal sections (Renney Slip and Marloes Sands), but high-resolution chemostratigraphy permits 11 subdivisions to be distinguished. Some chemostratigraphical units can be traced between the sections, whereas others are locally absent. The correlation of the chemostratigraphical units has been compared with sea-level cycles identified by a study of the frequency, distribution and characteristics of storm-beds using proximality trend analysis. This suggests a synchroneity of traceable chemostratigraphical units within the Deadman's Bay Member, indicating that deposition began in the Renney Slip Section, and that a greater water depth was achieved there. A holistic assessment shows that the Coralliferous Formation onlaps an unconformity surface with a palaeo-relief of 57 m, over a current distance of 3 km. Further considerations of benthic assemblages, subsidence rates and global sea-level fluctuations support the presence of a late Telychian transgression with glacio-eustasy contributing between 40 and 70 m to that sea-level rise. [ABSTRACT FROM AUTHOR]

The early lithification of carbonate mud during the subaerial exposure stage under semiarid conditions has been proposed to facilitate dolomite formation. However, how the biogeochemical processes during subaerial diagenesis promote dolomite formation remains unclear. Here, we employ a multiproxy approach to investigate the process of dolomite formation by analysing modern dolomite crusts forming in lagoon Brejo do Espinho. Petrological analysis reveals that the crusts consist of coexisting high-Mg calcite and dolomite. Low Fe and Mn concentrations indicate the formation of dolomite under oxic conditions, whereas a higher Sr concentration in well-lithified crust suggests primary bacterial-induced dolomite precipitation. The Mg isotopic composition of the crusts exhibits a lighter value than that of modern sabkha dolomite, suggesting different dolomitization processes and Mg sources. The more negative δ 13C values of the crusts than those of the unlithified carbonate mud in lagoon Brejo do Espinho indicate the incorporation of 13C-depleted organic carbon. The biogeochemical processes related to decaying organic matter during subaerial diagenesis generate partially oxidized organic matter that promotes Mg2+ dehydration and enhances the dissolution of primary high-Mg calcite, ultimately triggering the transition of high-Mg calcite to dolomite and/or the direct precipitation of dolomite. The ancient 'dolomite factory' operated through the cyclic deposition of carbonate sediments and penecontemporaneous subaerial diagenesis. Thematic collection: This article is part of the Towards unravelling the 'Dolomite Problem': new approaches and novel perspectives collection available at: https://www.lyellcollection.org/topic/collections/towards-unravelling-the-dolomite-problem [ABSTRACT FROM AUTHOR]

Fold-and-thrust belts are structural features that accommodate upper-crustal shortening by the growth of a series of thrust faults and folds. Recent studies show that a better understanding of the structure and sedimentation styles of fold-and-thrust belts and their associated basins can provide crucial insights for improved interpretations of the evolution of ancient and modern convergent margins and the mechanisms of intracontinental deformation. To achieve a more comprehensive understanding of the development of contractional orogenic belts, this thematic collection gathers contributions that explore different types of fold-and-thrust belts at various scales around the world, via different approaches including theory development, structural and stratigraphic observations from the field, geophysical analyses, and numerical modelling. Case studies include the northern margin of the Tibetan plateau and Pamir region, the Timanian and Caledonian orogenies in northern Norway, orogenic belts in western Laurentia, and the Andes of western South America. These studies reemphasize the importance of integrating broad datasets when documenting the distribution, geometry, and kinematics of structures in fold-and-thrust belts and their associated basins, including field-based structural observations, provenance, low-temperature thermochronologic, geomorphologic, and subsurface data, and analog and numerical models. This thematic collection aims to encourage further efforts for comparative studies of the fold-and-thrust belts around the world and proposes interdisciplinary research to address outstanding questions in the study of contractional orogens. Thematic collection: This article is part of the Fold-and-thrust belts collection available at: https://www.lyellcollection.org/topic/collections/fold-and-thrust-belts-and-associated-basins [ABSTRACT FROM AUTHOR]

The article offers information about the hydrocarbon exploration in the levant basin offshore Israel. It mentions that Israel Ministry of Energy has been involve in the review of fundamentals of hydrocarbon plays in the area, including stratigraphic correlation, source models and reservoir concepts, along with boosting the play and prospect inventory.

The entire Lower Fox River and inner bay of Green Bay, in northeastern Wisconsin, have been listed as impaired by the Wisconsin Department of Natural Resources (WDNR) for low dissolved oxygen and degraded habitat, with total phosphorus (TP) and total suspended solids (TSS) concentrations listed as the likely causes of these impairments. To restore the Fox River and Green Bay, total maximum daily loads (TMDLs) were developed for TP and TSS, and actions were taken throughout the Fox River Basin to improve water quality. In this study, we estimated concentrations and loads of TP, dissolved phosphorus (DP), and TSS at the Lake Winnebago outlet, De Pere, and the mouth of the Fox River from water year (WY) 1989 to WY 2021; described changes in concentrations and loads through time during this period; and compared the concentrations and loads for the most recent 5-year period (WYs 2017-21) with the WDNR criteria for TP impairment and the TMDL loading goals. TP, DP, TSS, and total suspended sediment concentration data were obtained from NEW Water, the brand of the Green Bay Metropolitan Sewerage District; the WDNR; and the U.S. Geological Survey and combined into one dataset. All the TSS and total suspended sediment data were used together with no adjustment factor and are referred to as simply "TSS." During WYs 1989-2021, mean annual TP concentrations increased from 0.089 milligram per liter (mg/L) at the Lake Winnebago outlet to 0.128 mg/L at the mouth of the Fox River, and concentrations decreased at all three sites from WY 1989 to WY 2021. The most recent (WYs 2017-21) median May-October TP concentrations were just less than the 0.1-mg/L WDNR criterion for TP impairment at the two upstream sites (Lake Winnebago outlet and De Pere) but were slightly greater than the criterion for impairment at the mouth of the Fox River. Mean annual DP concentrations increased from 0.024 mg/L at the Lake Winnebago outlet to 0.036 mg/L at the mouth of the Fox River. DP concentrations increased from WY 1989 to WY 2021 at the Lake Winnebago outlet but not at the other sites. Mean annual TSS concentrations increased from 13.5 mg/L at the Lake Winnebago outlet to 23.9 mg/L at the mouth of the Fox River and have decreased at all three sites from WY 1989 to WY 2021. The recent median May-October TSS concentrations were less than the 20-mg/L WDNR criterion for impairment at all three sites. Streamflow and TP, DP, and TSS loads increased from the Lake Winnebago outlet to the mouth of the Fox River (TP loads increased from 360 to 557 metric tons per year [t/yr], DP loads increased from 114 to 162 t/yr, and TSS loads increased from 60,400 to 122,600 t/yr). At the Lake Winnebago outlet, DP concentrations and TP and DP loads increased from WY 1989 to WY 2021 because of an increase in DP concentrations in Lake Winnebago resulting from the lake no longer being phosphorus limited in late summer with biological processes not consuming the DP in the lake and an increase in streamflow leaving the lake. Although TP and TSS concentrations decreased at De Pere and the mouth of the Fox River, there was little change in the loading because of an increase in flow. Flow-normalized TP and TSS loads at De Pere and the mouth of the Fox River decreased possibly because of implementation of agricultural conservation management practices, reductions in point-source discharges in its drainage basin, and deposition of sediment and phosphorus in recently dredged areas of the Lower Fox River. Additional studies are needed to determine the relative importance of each of these actions and whether the decrease in concentrations and flow-normalized loads will continue to be observed in the Fox River. [ABSTRACT FROM AUTHOR]

Bathymetric data were collected at 10 water-supply lakes in north-central and west-central Missouri by the U.S. Geological Survey (USGS) in cooperation with the Missouri Department of Natural Resources and in collaboration with various local agencies, as part of a multiyear effort to establish or update the surface area and capacity tables for the surveyed lakes. The lakes were surveyed in June and July 2020. Seven of the lakes had been surveyed by the USGS between 2002 and 2007, and the recent surveys were compared to the earlier surveys to document changes in the bathymetric surface and capacity of the lake and produce a bathymetric change map. Bathymetric data were collected using a high-resolution multibeam mapping system mounted on a boat. Supplemental depth data at two of the lakes were collected in shallow areas with an acoustic Doppler current profiler on a remotecontrolled boat. Data points from the various sources were exported at a gridded data resolution appropriate to each lake, either 0.82 foot or 1.64 feet. Data outside the multibeam survey extent and greater than the surveyed water-surface elevation generally were obtained from data collected using aerial light detection and ranging (lidar) point cloud data, except at Holden City Lake. A linear enforcement technique was used to add points to the dataset in areas of sparse data (the upper ends of coves where the water was shallow or aquatic vegetation precluded data acquisition) based on surrounding multibeam and upland data values. The various point datasets were used to produce a three-dimensional triangulated irregular network surface of lake-bottom elevations for each lake. A surface area and capacity table was produced from the threedimensional surface for each lake showing surface area and capacity at specified lake water-surface elevations. Various quality-assurance tests were conducted to ensure quality data were collected with the multibeam, including beam angle checks and patch tests. Additional quality-assurance tests were conducted on the gridded bathymetric data from the survey, the bathymetric surface created from the gridded data, and the contours created from the bathymetric survey. If data from a previous bathymetric survey existed at a given lake, a bathymetric change map was generated from the elevation difference between the previous survey and the 2020 bathymetric survey data points. After reconciling any vertical datum disagreement between the previous survey and the 2020 survey, coincident points between the surveys were identified, and a bathymetric change map was generated using the coincident point data. A decrease in capacity was observed at nearly all the lakes for which a previous survey existed, and the mean bathymetric change between the surveys was positive at all the lakes. The decrease in capacity at the primary spillway elevation ranged from -0.4 percent at Edwin A Pape Lake to 9.4 percent at upper Higginsville Reservoir. The mean bathymetric change ranged from 0.03 foot at Garden City New Lake to 1.75 feet at Harrisonville City Lake, which corresponds to a time-averaged mean bathymetric change ranging from 0.002 foot per year at Garden City New Lake to 0.132 foot per year at Harrisonville City Lake. The computed volumetric sedimentation rate generally ranged from 0.04 to 4.91 acrefeet per year at Garden City New Lake and Holden City Lake, respectively; however, Harrisonville City Lake had a substantially larger volumetric sedimentation rate of 42.7 acre-feet per year, corresponding to the substantial mean bathymetric change of 1.75 feet and combined with the relatively shorter interval between surveys. Harrisonville City Lake also had the second-largest decrease in capacity at the spillway elevation of 5.9 percent. As with the 2019 surveys, some changes observed in the bathymetric change maps likely result from the difference in data collection equipment and techniques between the surveys. Certain apparent erosional features around the perimeter of certain lakes may be the result of wave action or compaction of sediments exposed to air during low-water years, or may indicate an unidentified but systemic error in the older singlebeam echosounder survey data. [ABSTRACT FROM AUTHOR]

The U.S. Geological Survey Precipitation Chemistry Quality Assurance project (PCQA) operated four distinct programs to provide external quality-assurance monitoring for the National Atmospheric Deposition Program's (NADP) National Trends Network (NTN) and Mercury Deposition Network (MDN) during 2019-20. The NTN programs included (1) a field audit program to evaluate sample contamination and stability, and (2) an interlaboratory comparison program to evaluate analytical laboratory performance. The MDN programs included the (3) system blank program to evaluate sample contamination and stability, and (4) an interlaboratory comparison program. The results indicated increased levels of sample contamination compared to previous years for NTN samples and decreased contamination in MDN samples. Strong analytical laboratory performance with low overall variability and bias in concentration data were indicated for the NTN's Central Analytical Laboratory. A positive bias in the hydrogen ion concentrations in NTN samples during 2019 was eliminated by correction of a pH calibration protocol during 2020. The MDN's Mercury Analytical Laboratory performance declined in 2020 compared to 2019 as indicated by increased variability in analytical results and a negative bias of approximately -1 nanogram per liter in the concentrations of total mercury. Slight perturbations in contamination levels in NTN samples and in analytical performance for MDN are considered small. The PCQA results indicate that NADP data continue to be of sufficient quality for applications in independent research and NADP data products, including spatial interpolations and time trends for chemical constituents in wet deposition. Small shifts in data quality indicated by the 2019-20 PCQA results are intended to be used for interpretation of the NADP data products. [ABSTRACT FROM AUTHOR]

In summary, the parsimonious explanation is that the mylonitic lineation is the LDZ transport direction, and that the LDZ is part of the larger Keisarhjelmen detachment, along with the overlying Wilhelmtinden mylonite zone (Fig. LDZ kinematics [8] describe a shallowly NNW-plunging lineation on the west-dipping mylonitic foliation (their fig. 8), but with uncertain kinematics as indicators were not observed. [8] present valuable new isotopic and field data regarding NW Spitsbergen's tectonic history, and propose the existence of the Germaniahalvøya terrane with Scandian (Late Caledonian) igneous activity and deformation. Within this terrane, the Lerner Deformation Zone (LDZ) is cast as an east-directed thrust, with the Liefdefjorden Migmatite Complex in the footwall and Lenerøyane Group metasediments above. [Extracted from the article]

As Mars transitioned from an early Earth-like state to the cold desert planet it is today, it preserved a near pristine record of surface environments in a world without plate tectonics and complex life. The records of Mars' Earth-like surfaces have remained largely untouched for billions of years, allowing space exploration to provide critical insights about the early days of our own planet. Here, we first review what Mars has taught us about volcanic, tectonic and metamorphic processes in the absence of discrete plates, drawing comparisons with the terrestrial and venusian records. Then, we summarize advances in understanding its early surface environments, including impact cratering, hydrological, sedimentary and geochemical processes. Altogether, the martian record provides a picture of early environments that were similar to modern terrestrial ones in many respects, with sediment and geochemical cycling, hydrothermal systems capable of hosting life, but with the exception that topography, sediment and heat sources were provided by volcanoes and impact cratering rather than plate tectonics. Mars thus offers a lens through which one might catch a glimpse of Earth's infancy, provided exploration efforts continue to refine our understanding of the similarities between Earth and Mars as well as the specificities of each planet. [ABSTRACT FROM AUTHOR]

The article explores recent research on sedimentary geology, focusing on the distinction between translating and expansional point bars in meandering channels, particularly in the McMurray Formation of Canada. It also discusses the morphological differences between these point bars, the influence of flow dynamics on sediment deposition, and the importance of core and ichnofacies analysis in determining the depositional environment.

A recent study conducted at University Hospital Limoges in France explored the use of sedimentation field-flow fractionation (SdFFF) as a method for rapid antimicrobial susceptibility testing (AST). The researchers evaluated the effectiveness of SdFFF in determining the susceptibility or resistance of Escherichia coli strains to antibiotics. The results showed that SdFFF provided accurate and reliable AST results in less than 3 hours, with high categorical agreement, sensitivity, and specificity compared to the reference method of broth microdilution. This study suggests that SdFFF could be a valuable tool for early and appropriate antibiotic therapy. [Extracted from the article]

A recent research study conducted at King Fahd University of Petroleum and Minerals explores the use of geopolymer cement as a potential alternative to Portland cement in the oil and gas industry. Geopolymer cement is known for its environmental benefits and lower energy consumption during manufacturing. The study focuses on addressing the sedimentation issue in high-density geopolymer cement slurries by incorporating perlite powder. The results show that the addition of perlite significantly reduces sedimentation and improves the properties of the geopolymer cement. The study suggests that a perlite concentration of 3% by weight of binder is optimal for achieving desirable mixability and rheological properties. [Extracted from the article]

Lake Powell is the second largest constructed water reservoir by storage capacity in the United States and represents a critical component in management of water resources in the Colorado River Basin. The reservoir provides hydroelectric power generation at Glen Canyon Dam, banks water storage for the Upper Colorado River Basin, stabilizes water commitments downstream, and buffers the Lower Colorado River Basin, including Lake Mead, against sedimentation and fluctuations in hydrological conditions. With completion of the dam in 1963, Lake Powell steadily filled with water before reaching full pool in 1980 and has become a popular destination for recreation, welcoming more than 4 million visitors per year. Since the early 2000s, severe drought and increases in water demand have resulted in a significant drop in reservoir elevation and stored water, prompting a heightened level of interest in the current state and future of Lake Powell. Beginning in 2017, the U.S. Geological Survey, in cooperation with the Bureau of Reclamation, completed topobathymetric surveys of Lake Powell for the first update of elevation-area-capacity relationships since 1986. This report presents results of these surveys and comparisons with estimates from previous surveys. The storage volume and surface area, as of completion of the topobathymetric survey in spring 2018, are calculated at 0.33-foot (0.10-meter) increments for elevations ranging from 3,120.08 to 3,717.19 feet above the North American Vertical Datum of 1988 (NAVD 88). Between 0.33-foot increments, the storage volumes and areas were linearly interpolated at 0.01-foot intervals. Interpolation error in the 0.01-foot interval estimates was assessed at lower (3,160.00-3,161.00 feet above NAVD 88), middle (3,400.00-3,401.00 feet above NAVD 88), and upper (3,700.00-3,711.00 feet above NAVD 88) elevations. The interpolated storage capacity and area estimates are comparable to the measured values with differences ranging from 0.00 to 0.02 percent and from -0.01 to 0.03 percent, respectively. Current storage capacity at full pool (3702.91 feet above NAVD 88) is 25,160,000 acre-feet. Compared to previously published estimates, this volume represents a 6.79 percent or 1,833,000-acre-foot decrease in storage capacity from 1963 to 2018 and a 4.00 percent or 1,049,000-acre-foot decrease from 1986 to 2018. Areal extent, as of spring 2018, at full pool is 159,200 acres, which represents a 1.33-percent decrease from 1963 to 2018 and a 0.96 percent decrease from 1986 to 2018. [ABSTRACT FROM AUTHOR]

The article focuses on coastal communities, and various challenges faced by them due to climate change, topics include, acidification of the ocean, sedimentation, and rising groundwater, and ReMain Nantucket, an island organization discovers, a design that can impact decisions and attitudes around coastal resilience.

The article discusses the impact of the Three Gorges dam on the Yangtze River in China. The author, who traveled to cities along the Yangtze, from Chongqing to Badong, discusses the accumulation of silt throughout the Three Gorges Dam reservoir due to a miscalculation of water flow, according to engineering geologist Fan Xiao, the city of Fengjie, which was rebuilt after the dam flooded it, dam-triggered earthquakes, and reduced downstream flow, which is drying the Yangtze floodplain.

The article presents travel guide of Thai Peninsular for geotourist, including recommendations to visit succession of Paleozoic and Mesozoic rocks; boat trip to northern Phang Nga Bay to visit what is commonly known as James Bond's Island; and marine shelf sedimentation.

Researchers at the Wuhan Institute of Biological Products Co. Ltd. in China have conducted a study on enterovirus A71 (EV71), which causes hand, foot, and mouth disease (HFMD). The study focused on the different forms of the virus particles, empty particles (EPs) and full particles (FPs), and the need for effective analytical methods to detect and quantify these forms. The researchers used sedimentation velocity analytical ultracentrifugation (SV-AUC) to analyze and quantify the proportions of EPs and FPs. The study concluded that SV-AUC can be used for quality control of the EV71 vaccine and to ensure consistency in the production process. [Extracted from the article]

The article offers information on the Jurassic marine Vaca Muerta unit, which has significant potential with an estimated 308 TCF of gas and 16.2 billion barrels of oil. Topics include various facies present in the unit, such as volcaniclastic, carbonate, and mixed siliciclastic-carbonate, with bituminous marls being particularly noteworthy.

The article provides information on the geological characteristics of the Niger Delta Basin, highlighting the Akata-Agbada Petroleum system as a highly prospective source of hydrocarbons. It focuses on a 4700 sq. km area in the northwestern Nigerian offshore, discussing how MegaSurveyPlus 3D seismic data is used to reveal the interplay between shale tectonics and turbidite channel deposition, improving geological resolution and de-risking prospectivity in the region.

The article presents the discussion on Geological fieldwork helping in gaining a better understanding of the development and potential productivity of the off shore Natuna basins of the South China Sea. Topics include high sediment leading to deposition of thick successions forming productive hydrocarbon playing throughout the abundant basins of the region; and high sediment leading to deposition of thick successions forming productive hydrocarbon throughout the abundant basins of the region.

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 [ABSTRACT FROM AUTHOR]

The article discusses that coastal and offshore East Africa hosts a variety of long recognised and well described source rocks. It mentions that limited East African coastal onshore and near shore success in terms of commercial hydrocarbon discoveries can largely be attributed to the dearth of published regional fieldwork. It also mentions that oil-prone source rock deposition can be enhanced by the nutrients supplied to sea life from ash falls during major volcanic episodes.

The Indus Molasse records orogenic sedimentation associated with uplift and erosion of the southern margin of Asia in the course of ongoing India-Eurasia collision. Detailed field investigation clarifies the nature and extent of the depositional contact between this molasse and the underlying basement units. We report the first dataset on detrital zircon U-Pb ages, Hf isotopes and apatite U-Pb ages for the autochthonous molasse in the Indus Suture Zone. A latest Oligocene depositional age is proposed on the basis of the youngest detrital zircon U-Pb age peak and is consistent with published biostratigraphic data. Multiple provenance indicators suggest exclusively northerly derivation with no input from India in the lowermost parts of the section. The results provide constraints on the uplift and erosion history of the Ladakh Range following the initial India-Asia collision. [ABSTRACT FROM AUTHOR]

A significant part of mélanges recognized in exhumed convergent margins around the world has been recently documented to have chiefly originated from masse transport and subsurface remobilization and disruption (i.e. mélanges, from sedimentary and mud–serpentinite diapiric processes and from in situ fluidification–disruption). Tectonic and/or sedimentary processes occurring during subsequent multiple deformational events of convergent margin evolution commonly overprint and significantly rework the primary (sedimentary or diapiric) mélange fabric, forming polygenetic mélanges. This ultimately complicates their distinction from true tectonic mélanges, masking part of the recorded tectono-sedimentary evolution of the associated convergent margin. The contributions gathered in this thematic collection explore with different approaches (from field structural and stratigraphic observations to geophysical analyses) different types of polygenetic mélange, at various scales, around the world. These studies conclude that the understanding of this type of mélange may provide crucial insights for a more detailed interpretation of the evolution of ancient and modern convergent margins, and of processes and mechanisms triggering potential natural hazards (earthquakes and tsunamis). Case studies include the Apennines in the Central Mediterranean region, the Carpathians in Central Europe and the Nankai Prism in Japan. Thematic collection: This article is part of the 'Polygenetic mélanges: a glimpse on tectonic sedimentary and diapiric recycling in convergent margins' collection available at https://www.lyellcollection.org/cc/polygenetic-melanges [ABSTRACT FROM AUTHOR]

In the Northern Apennine (Italy), the Internal Ligurian Units consist of Middle–Late Jurassic ophiolites covered by thick sedimentary deposits whose top is represented by the Early Paleocene Bocco Shale. This formation is characterized by mass-transport deposits interlayered with thin-bedded siliciclastic turbidites. The sedimentological and structural features of these mass-transport deposits reveal a long-lived history of recycling of heterogeneous material in a subduction setting. This history started with the frontal accretion of a fragment of oceanic crust into an accretionary prism whose lower slope was subsequently affected by tectonic erosion and consequent instability, leading to the production of mass-transport deposits and the transfer of material to the lower plate. These mass-transport deposits were subsequently underthrust and then again transferred to the base of the accretionary prism by coherent underplating, before their exhumation to the surface. The Bocco Shale is thus representative of a subduction setting where both accretionary and erosive events occurred, depending on changing boundary conditions. The reconstructed history for the Bocco Shale indicates that the sedimentary and gravitational processes both at the prism front and on the prism slope, possibly induced by alternating accretion and erosion events, are the most efficient mechanisms of lithological mixing and recycling in subduction margins. [ABSTRACT FROM AUTHOR]

The authors present results of the first high-resolution deep seismic reflection survey in the Pieniny Klippen Belt (PKB) in Poland. This survey sheds new light on the matter of olistostromes and the mélange character of the PKB. The sedimentary mass-transport deposits represented by olistoliths and olistostromes manifest themselves by different petrophysical parameters of rocks (velocity, density and resistivity) and seismic attributes. Seismic attributes are very effective in the interpretation of the geology of complex mélanges. The authors used selected attributes: low-pass filter, energy, energy gradient, dip-steered median filter, Prewitt filter, Laplacian edge enhancing filter and square root of the energy gradient. These attributes emphasize changes of the seismic image inside mélange zones. The distinguished olistoliths are now inside imbricated thrust structures and they are tectonically rearranged. Polygenetic mélanges in the PKB originated as a result of sedimentary and tectonic processes. The PKB in the investigated area forms several north-vergent thrust sheets belonging to the Złatne and Hulina nappes. Both nappes contain large chaotic, non-reflective olistoliths as well as the smaller mainly high-reflective olistoliths. Olistoliths are arranged parallel to the flysch layering and thrusts. The results presented confirm the postulated two olistostrome belts within the PKB structure. Thematic collection: This article is part of the Polygenetic mélanges collection available at: https://www.lyellcollection.org/cc/polygenetic-melanges [ABSTRACT FROM AUTHOR]

Sediment provenance analysis is important in reconstructing chronological and spatial relationships between source area erosion/exhumation and sediment deposition in adjacent basins. Here we provide new provenance data from conglomerate clast populations, sandstone petrography, heavy mineral assemblages and U–Pb detrital zircon geochronology from the 9 km-thick, Siluro-Devonian Lower Old Red Sandstone (LORS), northern Midland Valley Basin (MVB), Scotland. The MVB developed in the foreland to the Caledonian Orogeny and comprises a mixed succession of conglomerate and pebbly sandstone interbedded with volcanic lithologies. Analysis of 554 samples (137 petrographical thin sections across 22 formations/members; 390 conglomerate clast recordings across 7 locations; 17 heavy mineral and 10 detrital zircon samples) from the entire succession shows a proximal, consistent source or sources located to the east or NE. These results indicate that sediment derived directly from areas of Scandian uplift of Norwegian lithologies is unlikely to have made a significant contribution to the LORS of the northern MVB and the provenance instead lies more proximally in both the neighbouring Dalradian Supergroup metasedimentary rocks and other contemporaneous lithologies. The coarse-grained nature of the sedimentary rocks suggests consistent and continued uplift of these lithologies throughout deposition of the LORS. Integration of these provenance techniques allows robust interpretation of basin fill from a tectonically rejuvenating source in the Caledonian foreland. Supplementary material: MVB LORS palaeocurrent data; List of sample locations is available at https://doi.org/10.6084/m9.figshare.c.4661966 [ABSTRACT FROM AUTHOR]

The Polish Basin formed at the eastern periphery of the large epicontinental Permian-Mesozoic Central European Basin System. It was filled with several kilometres of siliciclastics, carbonates and thick Zechstein (Upper Permian) evaporites. Its axial part, the Mid-Polish Trough, which is characterised by a particularly thick Permo-Mesozoic sedimentary cover, developed partly above the Teisseyre-Tornquist Zone, a lithospheric-scale boundary located between the East European Craton and the West European Platform. Late Cretaceous-Palaeogene inversion of the Polish Basin was associated with uplift of the Mid-Polish Trough that now forms a large regional anticlinal structure referred to as the Mid-Polish Swell. A qualitative model of the Permo-Mesozoic geologic evolution of the central part of the Polish Basin, constructed using seismic and well data, suggests a significant role of localised extension and subsidence during Rotliegend (Drawa Formation) and Zechstein sedimentation. The Polish Basin was fully inverted during the Late Cretaceous to Palaeogene. Basin inversion within the study area was associated with substantial uplift of the hanging wall block of the Szubin Fault, final formation of the Szubin salt pillow, folding of the Mesozoic supra-salt overburden and formation of the Mid-Polish Swell. The crest of the Mid-Polish Swell was subsequently deeply eroded prior to sedimentation of the Neogene post-inversion cover. [ABSTRACT FROM AUTHOR]

Muds deposited in large-scale epicontinental seaways provide deep insights into palaeoclimates, biogeochemical cycles, sedimentation processes and organic carbon burial during exceptionally warm periods throughout the Phanerozoic. Temporal changes can be monitored at single locations but the key, larger scale oceanographical and related biogeochemical processes are likely to be more clearly revealed by comparisons between individual sub-basins within seaways. Here, we compare inorganic geochemical records from the Jurassic (upper Pectinatites wheatleyensis to lower Pectinatites pectinatus ammonite zones) of the Swanworth Quarry 1 Core from the Wessex Basin (Dorset, UK) to time-equivalent records from the Ebberston 87 Core in the Cleveland Basin (Yorkshire, UK), 400 km apart. Our synthesis shows that while the Dorset sediments were deposited in an energetically more dynamic setting than the Yorkshire sediments, the overarching climatic and oceanographical processes responsible for variations in organic carbon enrichment and sedimentation were similar. Intervals of coeval organic carbon-rich sedimentation occurred in both basins, and a particulate shuttle was intermittently active in both basins. Consistent with recent climate simulations, we conclude that tropical climate conditions, associated with enhanced nutrient supply, were key drivers of sedimentation between the Jurassic Wessex and Cleveland Basins. Supplementary material: Geochemical data discussed in the manuscript is available at: https://doi.org/10.6084/m9.figshare.c.4531532 [ABSTRACT FROM AUTHOR]

A patent application by inventors from Repligen Corporation has been made available online. The patent application describes a system and method for harvesting a product of interest from a bleed material in a perfusion bioreactor. The system includes a bioreactor, cell retention devices, harvest pumps, and a bleed recovery system. The invention aims to recover the product of interest from the bleed material without altering the culture environment. The patent application provides detailed descriptions of the components and operations of the system. [Extracted from the article]

A recent report from the Second Affiliated Hospital explores the incidence of nerve root sedimentation sign (SedSign) in patients with severe lumbar spinal stenosis (LSS). The study found that 85.52% of patients with severe LSS had a positive SedSign. The research also identified several risk factors associated with a positive SedSign, including the grade of degenerative facet joint, the thickness of ligamentum flavum, and the cross-sectional area difference. The study concludes that a positive SedSign can be helpful in diagnosing severe LSS, and suggests that compression of the dural sac from the rear may be a main risk factor. [Extracted from the article]

A recent study conducted by the Professional Compounding Centers of America (PCCA) analyzed the physical properties of a new anhydrous oral vehicle called SuspendIt(R) Anhydrous. The vehicle was designed for compounding pediatric oral liquids and was found to exhibit consistent physical properties and stability over time. The unique blend of excipients in its formulation allows for rapid redispersibility, sedimentation stability, accurate dosing, and enhanced gastrointestinal distribution and absorption. The study suggests that this anhydrous oral vehicle could serve as a versatile base for pediatric formulations, filling an important gap in pediatric drug delivery. Further research is needed to investigate its compatibility, stability, and performance with other drugs and in different clinical scenarios. [Extracted from the article]

This article discusses the impact of sedimentation on coral reefs, specifically focusing on the gene expression patterns of the Porites lobata coral species. The study used transcriptomics to identify genes, pathways, and molecular processes associated with the coral's ability to tolerate chronic, severe sedimentation and persist in turbid environments. The research found evidence of increased environmental sensing and cellular communication in response to sedimentation stress, as well as apoptosis pathways that help maintain colony integrity. The findings provide insight into the metabolic plasticity and acclimation potential of corals to sedimentation, contributing to our understanding of their resilience in turbid reef systems. [Extracted from the article]

The Vizcaino fore-arc basin accumulated approximately 4 km (-13,000 ft) of upper Albian-middle Eocene siliciclastic marine sedimentary rocks derived from the Peninsular Ranges in Baja California. Data from eight exploratory wells document the micropaleontological content and lithological characteristics of these rocks. The strata studied represent mostly neritic-upper bathyal marine environments and overlie a basement composed of Cretaceous granitic rocks, or Aptian-Albian volcaniclastic sedimentary rocks correlative with the Alisitos Formation. We recognize four major depositional sequences within the basin that are related to the regional geology. The basal Albian-Turonian sequence 1 represents the initiation of fore-arc basin sedimentation, contains continental conglomerates that change to bathyal shales, and correlates with the lower part of the Valle Group of the Vizcaino Peninsula. Sequence 2 is Coniacian-Paleocene, includes basal conglomeratic sandstones grading into Maastrichtian bathyal shales, and usually overlies a Coniacian-Santonian unconformity. Sequence 2 is represented at the surface by the Rosario Group in northwestem Baja Califomia and the upper part of the Valle Group in the Vizcaino Peninsula. Sequence 3 is Paleocene-middle Eocene, represents continuity of fore-arc sedimentation in neritic-upper bathyal conditions, is capped by a major unconformity, and correlates with the Sepultura and Bateque Formations to the north and south of the basin, respectively. The uppermost Miocene-Pliocene sequence 4 is composed of marine sanclstone-siltstone unconformably overlying sequence 3 and is correlative with the Tortugas Formation that represents sedimentation after the end of subduction of the Farallon plate beneath the North America plate. [ABSTRACT FROM AUTHOR]

Highlights • A nonlinear DAE of the velocity v of a falling sphere in non-Newtonian fluid will be proposed by directly learning the data. Our model successfully simulates the sustaining oscillations and abrupt increase during the sedimentation of a sphere. It presents the behavior of a chaotic system which is highly sensitive to initial conditions and experimentally nonreproducible. The normalized representation covers both the classical physical laws and the nonuniform oscillations. The data-driven idea will provide scientists with more important tools to support their discovery in the future. Abstract In this paper, we will introduce a mathematical model of nonlinear jerk equation of velocity v = η 1 η 2 v ″ + 1 v ″ + η 3 v ″ to simulate the nonuniform oscillations of the motion of a falling sphere in the non-Newtonian fluid. This differential/algebraic equation is established only by learning the experimental data with the generalized Prony method and sparse optimization method. From the numerical results, our model successfully simulates the sustaining oscillations and abrupt increase during the sedimentation of a sphere through a non-Newtonian fluid. It presents the behavior of a chaotic system which is highly sensitive to initial conditions. More statistical and physical discussions about the dynamical features of the model are provided as well. Our model can be interpreted as a nonlinear elastic system, and includes both the uniform and nonuniform oscillatory motion of the falling sphere. [ABSTRACT FROM AUTHOR]

Predicting vertical and lateral facies variations in various depositional environments remains a major challenge in the oil and gas industry because it impacts petroleum system assessments and the associated exploration-risking phase. The use of multidisciplinary constraints (geomorphology, geology, geophysics] in forward stratigraphic models sheds light on the complex interaction of local, regional, and global driving mechanisms that influence sediment transport and deposition along continuously evolving landscapes. In this paper, we develop an integrated statistical approach to examine the sensitivity of forward stratigraphic models in complex salt provinces to several parameters, including water discharge, sedimentary load, grain size and associated diffusion coefficients, and slope. This statistical analysis was applied to the Barremian-Albian sequence of the central Scotian Basin (Canada] and highlights the influence of complex salt kinematics on sediment pathway diversion and accumulation around salt domes and canopies. Forward stratigraphic modeling results point to regions of higher probability of Lower Cretaceous sandy reservoirs. Automating simulation runs significantly reduced the time required to achieve a statistically valid number of simulations and allowed the sensitivity of the model to be evaluated. [ABSTRACT FROM AUTHOR]

The identification of extensive intrusive igneous complexes in both subsurface data and field studies has led to the quantification of the volumes of igneous material present within sedimentary sequences. Despite this research, however, little connection has been established between the amount of igneous material intruded into a basin and its effect on subsequent basin evolution in terms of burial and loading. We used subsurface data from the Faroe-Shetland Basin to investigate igneous intrusions with the aim of understanding how additional igneous material influences basin evolution. We found that the total estimated thickness of Cretaceous sediments is likely to be an overestimate because the sedimentary fill consists of significant quantities of igneous material emplaced during the Paleocene (56-54 Ma). This additional igneous material has not previously been accounted for in estimates of sedimentation rates and the burial history of the Faroe-Shetland Basin. Petroleum system modelling to understand the generation and expulsion of hydrocarbons benefits from correct estimates of basin fill. The overthickening of basins by igneous material will affect the timing of hydrocarbon generation and therefore the correct evaluation of exploration targets. The volume of igneous material and the time at which this material was emplaced must be acknowledged and considered in order to fully understand basin evolution. [ABSTRACT FROM AUTHOR]

At least four horizons of enhanced anoxia (anoxic horizons; AHs) are recognized in the uppermost Eifelian-Middle Frasnian mudrock-dominated strata of the Mackenzie Valley and Peel area of NW Canada. Aluminium-normalized Mo and U logs in two cored sections reveal AH-I at the Eifelian-Givetian boundary, AH-II in basal Frasnian, and AH-III and AH-IV bundled in the Middle Frasnian interval. These four horizons are characterized by attenuated siliciclastic components. Spectral gamma-ray K + Th and U are the best tools to trace these horizons in wells and outcrops. AHs are biostratigraphically correlated with 'black-shale events' in several basins of the world. Depositional environment is depicted as a stratified basin where the water-column chemocline defined co-sedimentation of anoxic mudrocks in topographic lows and oxic grey shales and carbonate banks on seafloor elevations. Based on inductively coupled plasma elemental data from 1687 samples, siliciclasticlean basinal mudrock units that host AHs are strongly enriched in Mo (median EFMo ~ 97-172 EFMo/EFU ≈ (3-3.5) × SW, where EFMo and EFU are respectively Al-normalized Mo and U in enrichment factor notation and SW is average present-day seawater value) compared with siliciclastic-rich units (median EFMo ~ 17-37) and show strong EFU/EFMo covariation (r ≈ 0.8 in Canol Formation and Bluefish Member). Supported by a lack of geological evidence for an oceanographic barrier, this enrichment indicates unrestricted water exchange with Panthalassa. At the same time, development of oligotrophy is indicated by a lack of P enrichment and weak to non-existent enrichment in Zn and Cu. These features are reconciled through a model by earlier workers that involves a global shift to a warm greenhouse mode with slowed oceanic convection, expanded oxygen minimum zones and a failure of nutrient resupply from the upwelling. The onset of mass degassing in continental large igneous provinces represents a potential trigger for this mid-Devonian shift. Devonian black-shale events in this scenario represent genuine oceanic anoxic events marking hothouse episodes in their nascent form. [ABSTRACT FROM AUTHOR]

How and when sediment moves from terrestrial sources to deep-water sinks is a significant area of research. We have used an array of seismic, borehole, and gravity core data sets to explore the timing and magnitude of sediment-routing to Pearl River slope over the last 478 k.y. As predicted by existing sequence stratigraphic models, most sediment dispersal to deep water is shown to have occurred during glacial sea-level falls; however, clastic detritus was still being transported into deep water during interglacial sea-level rises. We suggest that sediment routing to deep water during interglacial sea-level rise is caused by summer monsoon strengthening and resultant warmer and wetter climates, both of which have enhanced effective precipitation and sediment supply. Although some models for the delivery of sediment to deep-water basins stress the importance of proximity of canyon heads and coeval shorelines, we observed that sediment routing to deep water could occur regardless of the distance between channel head and coeval shorelines. In the present case, the success of delivery is related to the combined effects of (1) the short duration and high amplitude of sea-level oscillations during the past 478 k.y. and (2) the enhanced sediment supply caused by more humid climates and greater temperature difference between glacial and interglacial period. This hypothesis is supported by (1) observations that outer Pearl River deltas prograded as an apron over preexisting shelf edges for 10-15 km (6-9 mi) and (2) the occurrence of slope channels extending back to prodelta reaches of Pearl River shelf-edge deltas. [ABSTRACT FROM AUTHOR]

The article explores the origin of the ocean which has the repetition of erosion and sedimentation. The constant volume of water through the ages is investigated as well as the varied level of the sea. The article also discusses several speculations about the early history of the Earth. A probable arrangement of continents before the formation of the Atlantic Ocean is determined by the aid of a computer.

The article focuses on various developments around the world during 1872. First article focuses on the report of late Edmund Ruffin, agricultural surveyor of the U.S. state. The rich deposits of marls and marl-stones formed a portion of the geological structure of U.S. had been surmised. The investigations of Ruffin were chiefly directed towards the discovery and location of deposits of marl. Another article focuses on the writings of François Marie Arouet de Voltaire. The collection of Voltaire works is not one which can ever be read from beginning to end, but nothing is more delightful and more absorbing than to go through it, taking sometimes one volume and sometimes another.