Miracle-dz/UniFAR-FTUs huggingface dataset:
Trapping of aqueous fluids in the deep crust

Free aqueous fluids in the deep (ductile) crust have residence times there which are very short in geological terms. If not consumed by retrograde metamorphic reactions, they empty very rapidly upwards. This can be shown by applying the theory of magma percolation in a ductile host to the problem of aqueous fluid percolation. Below the brittle-ductile transition thermal activation of ductility is strong enough to facilitate the rapid evolution of porosity and consequently allow rapid fluid transport. In the cooler crust above the brittle-ductile transition, however, this mechanism vanishes. As a consequence, fluid overpressures resulting from the accumulation of fluid in the transition zone must induce hydraulic fracturing rather than pore inflation. In regions of horizontally compressive regional stress, the commonest situation in stable continental crust, these fractures will be horizontal. Aqueous fluids rising through or liberated from the lower crust will therefore probably accumulate (at least initially) at the brittle-ductile transition in horizontally extensive reservoirs with high horizontal permeability but low vertical permeability.
Hydrogeomorphic properties of simulated drainage patterns using digital elevation models: the flat area issue / Propriétés hydro-géomorphologiques de réseaux de drainage simulés à partir de modèles numériques de terrain: la question des zones planes

Abstract Flat areas are a critical issue for the characterization of drainage patterns using digital elevation models (DEM). In this work, flat area removal and flow direction algorithms are implemented, and also a physically-based DEM correction model is introduced, for investigating their influence on the topological properties of the channel network, the Hortonian parameters and the hillslope width function. Differences of results, as compared to the standard procedures implemented in widely-used GIS-based hydrological packages, show the importance for hydrogeomorphic modellers to consider the use of more detailed approaches.
Thorium abundances of basalt ponds in South Pole-Aitken basin: Insights into the composition and evolution of the far side lunar mantle

[1] Imbrian-aged basalt ponds, located on the floor of South Pole-Aitken (SPA) basin, are used to provide constraints on the composition and evolution of the far side lunar mantle. We use forward modeling of the Lunar Prospector Gamma Ray Spectrometer thorium data, to suggest that at least five different and distinct portions of the far side lunar mantle contain little or no thorium as of the Imbrian Period. We also use spatial correlations between local thorium enhancements and nonmare material on top of the basalt ponds to support previous assertions that lower crustal materials exposed in SPA basin have elevated thorium abundances, consistent with noritic to gabbronoritic lithologies. We suggest that the lower crust on the far side of the Moon experienced multiple intrusions of thorium-rich basaltic magmas, prior to the formation of SPA basin. The fact that many of the ponds on the lunar far side have elevated titanium abundances indicates that the far side of the Moon experienced extensive fractional crystallization that likely led to the formation of a KREEP-like component. However, because the Imbrian-aged basalts contain no signs of elevated thorium, we propose that the SPA impact event triggered the transport of a KREEP-like component from the lunar far side and concentrated it on the nearside of the Moon. Because of the correlation between basaltic ponds and basins within SPA, we suggest that Imbrian-aged basaltic volcanism on the far side of the Moon was driven by basin-induced decompressional melting.
30. Sounds Good: Using Digital Audio for Evaluation Feedback

Feedback on student work is problematic for faculty and students in British higher education. Evaluation feedback takes faculty much time to produce and students are often dissatisfied with its quantity, timing, and clarity. The Sounds Good project has been experimenting with the use of digital audio for feedback, aiming to save faculty time and give students richer learning experiences. Results are generally positive, with students and faculty acknowledging the higher quality of audio feedback. Favourable circumstances for timesaving have been identified and there is reason to believe that more faculty will eventually be able to save time on feedback without loss of quality. Practice recommendations for the use of audio feedback are given. Some issues for further research are identified.
Sensitivity of the North Atlantic Ocean Circulation to an abrupt change in the Nordic Sea overflow in a high resolution global coupled climate model

[1] The sensitivity of the North Atlantic Ocean Circulation to an abrupt change in the Nordic Sea overflow is investigated for the first time using a high resolution eddy-permitting global coupled ocean-atmosphere model (GFDL CM2.5). The Nordic Sea overflow is perturbed through the change of the bathymetry in GFDL CM2.5. We analyze the Atlantic Meridional Overturning Circulation (AMOC) adjustment process and the downstream oceanic response to the perturbation. The results suggest that north of 34°N, AMOC changes induced by changes in the Nordic Sea overflow propagate on the slow tracer advection timescale, instead of the fast Kelvin wave timescale, resulting in a time lead of several years between subpolar and subtropical AMOC changes. The results also show that a stronger and deeper-penetrating Nordic Sea overflow leads to stronger and deeper AMOC, stronger northward ocean heat transport, reduced Labrador Sea deep convection, stronger cyclonic Northern Recirculation Gyre (NRG), westward shift of the North Atlantic Current (NAC) and southward shift of the Gulf Stream, warmer sea surface temperature (SST) east of Newfoundland and colder SST south of the Grand Banks, stronger and deeper NAC and Gulf Stream, and stronger oceanic eddy activities along the NAC and the Gulf Stream paths. A stronger/weaker Nordic Sea overflow also leads to a contracted/expanded subpolar gyre (SPG). This sensitivity study points to the important role of the Nordic Sea overflow in the large scale North Atlantic ocean circulation, and it is crucial for climate models to have a correct representation of the Nordic Sea overflow.
Automatic phase correction of common-midpoint stacked data

The residual wavelet on a processed seismic section is often not zero phase despite all efforts to make it so. In this paper we adopt the convolutional model for the processed seismogram, assume that the residual phase shift can be approximated by a frequency-independent constant, and use the varimax norm to generate an algorithm to estimate the residual phase directly. Application of our algorithm to reflectivities from well logs suggests that it should work in the majority of cases so long as the reflectivity is non-Gaussian. An application of our algorithm to stacked data enhances the interpretability of the seismic section and leads to an improved match between the recovered relative acoustic impedance and a measured velocity log.
Barents Sea seasonal ice zone features and processes from ERS 1 synthetic aperture radar: Seasonal Ice Zone Experiment 1992

Sea ice features and processes in the Barents Sea were studied during the Seasonal Ice Zone Experiment 1992 (SIZEX92), a dedicated ERS 1 satellite synthetic aperture radar (SAR) field campaign carried out in March 1992. SIZEX92 was based around the research vessels Polarsyssel and Hakon Mosby. In situ oceanographic, meteorological, and ice measurements were made, coordinated with low-altitude aerial observations and ERS 1 SAR data acquired in near real time. Fifty-eight low-and full-resolution SAR scenes were obtained during SIZEX92, which provided a validation data set for ERS 1 SAR backscatter under winter conditions in the Barents Sea. Analysis of SIZEX92 data has provided geophysical insights, including a better understanding of Barents Sea ice edge freezing processes and ice edge development in response to atmospheric forcings. In particular, areas of new ice formation were found to be related to bathymetric features through their influence on the circulation of Arctic and Atlantic water masses. ERS 1 SAR image sequences revealed rapid, mesoscale variations in new ice areas and the ice edge in response to wind conditions. In addition to geophysical insight, SIZEX92 demonstrated some of the technical capabilities and limitations of ERS 1 SAR to identify new ice areas, the ice edge, ice floes, and ice types. Mapping new ice areas using satellite SAR data may be considered the most promising new application. The limitations of ERS-1 SAR-derived ice classification and ice motion estimates in the marginal ice zone are identified.
Neoproterozoic reef microstructures from the Little Dal Group, northwestern Canada

Basinal facies in the Neoproterozoic Little Dal Group contain large reefs up to 300 m in height and 8 km in diameter. In contrast to the stromatolitic composition typical of earlier Proterozoic buildups, Little Dal reefs consist mainly of three different calcareous microfossils. A tubule-thread microfossil, analogous to the calcimicrobe Girvanella in Paleozoic reefs, formed laminar-reticulate structures, like those in Ordovician bioherms. A clotted to saccate microfossil, comparable morphologically to Paleozoic Renalcis , constructed botryoidal to encrusting masses. An enigmatic component of multicellular appearance that has attributes of an early calcified metaphyte exhibits the encrusting sheetlike habit characteristic of middle to late Paleozoic algae. These reefs represent an intermediate stage between Proterozoic stromatolitic buildups and Paleozoic metazoan-calcimicrobial reefs and biogenic mounds.
Canary Current and North Equatorial Current from an inverse box model

[1] The large-scale Canary Basin circulation is estimated from a box inverse model applied to hydrographic data from a quasi-synoptic survey carried out in September 2003. The cruise consisted of 76 full depth CTD and oxygen stations. Circulation is required to nearly conserve mass and anomalies of salinity and heat within layers bounded by neutral surfaces. It permits advective and diffusive exchange between layers and an adjustment of the Ekman transport and the freshwater flux divergences. The Canary Current at the thermocline layer transports a net mass of 4.7 ± 0.8 Sv southward north of the Canary Islands from the African coast to 19°W. It is divided into a northward circulation at a rate of 1.1 ± 0.5 Sv between the African coast and Lanzarote Island and a southward transport of 5.8 ± 0.6 Sv. It transports North Atlantic Central Water and organic matters advected offshore by the filaments protruding from the upwelling system off northwest Africa. At 24°N, the Canary Current feeds the North Equatorial Current that transports a mixture of North and South Atlantic Central Waters westward. In the intermediate layer a southwestward flow of 1.2 ± 1.1 Sv transports Mediterranean Water to the Subtropical Gyre, though the highest salt flux is transported by a meddy. Oxygen distribution and mass transport suggest a northeastward deep flow of a water mass colder than 2.2°C consisting of diluted Antarctic Bottom Water. The heat and freshwater divergences and the average dianeutral velocity and diffusion between the sections and the African coast are negligible.
A potential century–scale rhythm in six major palaeoclimatic records in the northern hemisphere

Abstract. Six millennial proxy records of temperature in the northern hemisphere were analysed using both the Fourier and wavelet approaches. We found that the analysed temperature proxies have appreciable synchrony at multidecadal and centennial time scales. These data also show evidence for the presence of a roughly regular large‐scale rhythm with a periodicity of 50–130 years in the climate of the northern hemisphere over the last millennium. It is shown that the amplitude of this variation might reach 0.20–0.28°C and contribute appreciably to the rise of global temperature over the first part of the 20th century. Possible origins of the global centennial climatic cycles are discussed.
MEASUREMENT OF VORTICES IN MODEL PUMP-INTAKE BAY BY PIV

This paper describes experiments aimed at improving the understanding of vortices that form in water-pump intake bays. Experiments were conducted in a laboratory model of a simple intake bay comprising a vertical intake pipe with a bell mouth in a rectangular channel under conditions for which surface tension and free-surface elevation effects were small. The experiments comprised flow visualization followed by detailed measurements of the velocity field with particle-image velocimetry (PIV) in selected sections across the free-surface and wall-attached (subsurface) vortices. All vortices were found to meander in space. Depending on the submergence of the intake pipe and its position relative to the channel walls, some vortices had well-defined mean positions, while others were intermittent or exhibited bimodal behavior. The subsurface vortex strength depended on the distance between the wall or floor to which the vortex was attached and the intake pipe, with smaller distances promoting stronger vortices. The experiments clearly demonstrate the usefulness of PIV in obtaining the quantitative information that is required about the number, location, size, and strength of the vortices in order to develop and validate numerical models of pump intake flows.
Economic and Environmental Benefits from Canopy Sensing for Variable-Rate Nitrogen Corn Fertilization

Nitrogen (N) available to support corn production can be highly variable within fields. Canopy reflectance sensing for assessing crop N health has been proposed as a technology on which to base top-dress variable-rate N application. The objective of this research in Missouri and Nebraska was to evaluate the economic and environmental benefit of active-light crop-canopy reflectance sensors for corn N rate decisions. In Missouri, a total of 16 field-scale experiments were conducted over four seasons (2004-2007) in three major soil areas. Multiple blocks of randomized N rate response plots traversed the length of the field. Each block consisted of 8 treatments from 0 to 235 kg N ha-1 on 34 kg N ha-1 increments, top-dressed between V7-V11 vegetative growth stages. Canopy sensor measurements were obtained from these blocks and adjacent N-rich reference strips. A sufficiency index calculated from the sensor readings correlated with optimal N rate, but only in 50% of the fields. While soil type, fertilizer cost, and corn price all affected our analysis, a modest ($25 to $50 ha-1) profit using canopy sensing was found. Fertilizer savings of 10 to 50 kg N ha-1 could be expected in most situations, but savings also varied by reflectance readings, soil type, and fertilizer and grain prices. In the Nebraska studies, canopy sensing for one site allowed 39% savings in N applied compared to the traditional N management strategy, while producing similar grain yields. These results affirm using crop-canopy reflectance sensors for detecting corn N fertilizer needs that vary spatially within fields.
Vegetable Oil-Based Cannabis: Its Cannabinoid Profiling and Vegetable Oil-Based Cannabis: Its Cannabinoid Profiling and Photoprotective Effect on UVA-Irradiated Human Skin Photoprotective Effect on UVA-Irradiated Human Skin Keratinocytes Keratinocytes

Vegetable oils serve as affordable, non-toxic, and eco-friendly solvents for plant extraction. Chemical fingerprinting shows that vegetable oil-based cannabis has a cannabinoid profile similar to that of organic solvent-based cannabis. All samples possess antioxidative effects as they contain several cannabinoids and other unidentified compounds, with rice bran oil-based sample exhibiting the strongest effect. Tetrahydrocannabinol (THC) and cannabidiol (CBD) content in sesame oil-based and perilla seed oil-based cannabis differed significantly from that in virgin coconut oil (VCO)-based cannabis. In addition, THC and CBD content in all vegetable oil-based samples prepared using the heating and frying method differed significantly from that in samples prepared using conventional methods. The VCO-based cannabis was chosen to preliminarily test its photoprotective effect and antioxidant enzyme activity. The results showed that it can protect UVA-irradiated HaCaT cells. Pretreatment with VCO-based cannabis can promote Nrf-2/HO-1 signaling, thereby upregulating antioxidant enzymes and increasing the capacity of keratinocytes to detoxify oxidative insults. Herein, we present the first overview of the cannabinoid profile of vegetable oil-based cannabis, which can be used for quality control during the development of vegetable oil-based cannabis products. Furthermore, the skin photoprotective properties of oil-based extracts can provide supporting evidence for the formulation of cannabis-based skincare products.
The impact of floods on infiltration rates in a disconnected stream

A few studies suggest that infiltration rates within streambeds increase during the flood season due to an increase in the stream stage and the remove of the clogged streambed. However, some studies suggest that a new clogging layer will quickly form after an older one has been eroded, and that an increase in water depth will compress the clogging layer, making it less permeable during a flood event. The purpose of this work was to understand the impact of floods on infiltration rates within a disconnected stream. We utilized pressure data and daily streambed infiltration rates determined from diurnal temperature time series within a streambed over a period of 167 days for five flood events. Our data did not support the theory that floods linearly increase the infiltration rate. Since the streambed was clogged very quickly with a large load of suspended particles and compaction of the clogged layer, infiltration rates were also low during the flooding season. However, due to an increase in the wet perimeter within the stream during flooding periods, the total recharge amount to the aquifer was increased.
Recent and Holocene dynamics of a rock glacier system: The example of Langtalkar (Central Alps, Austria)

The Hinteres Langtalkar rock glacier (Gössnitztal, Hohe Tauern, Austria) has been part of a complex transportation system of debris and ice since the beginning of the Holocene and shows the highest creep rates of all rock glaciers measured in the Hohe Tauern Range. Results of movement analysis show that the entire rock glacier behaves very differently at different zones and that sudden temporal and spatial changes of velocity rates are a typical feature. Zones with high rates occur close to rather inactive zones and zones with low rates have rapidly accelerated within recent years. The increase in movement rates over time is probably caused by topography. These studies – especially the measurement of surface velocities and elevational changes – allow a differentiation of the rock glacier and a first attempt of a morphogenetic interpretation. In this context, it is important that the innermost part of the cirque was covered by a small cirque glacier during the Little Ice Age advance. This cirque glacier created a moraine complex which contributes to the material supply of the rock glacier. A first estimation of transportation rates is possible with the help of the measurement results available, leading to an estimation of a probable age of at least 4000 years.
Factors associated with in-school physical activity among urban children with asthma

ABSTRACT Objective: A cross-sectional study was conducted to determine if in-school physical activity (PA) varied by age, gender, weight and asthma status, participation in physical education (PE), outdoor recess, and other in-school PA among urban schoolchildren with asthma. Methods: PA was measured by tri-axial accelerometers. Height and mass were measured and overweight defined as BMI ≥85th percentile. Asthma impairment and risk were assessed as per national guidelines, and asthma status variable with three categories (mild, moderate, and severe) was created. Multivariable generalized linear mixed models adjusting for clustering due to school and student were fitted to identify variables predictive of PA. Results: 108 children with asthma participated. Children spent 374 minutes in school, of which 253 minutes were sedentary, 105 minutes in light PA, and 16 minutes in moderate-to-vigorous PA (MVPA). Only 3 participants reached the recommended ≥30 minutes/day of MVPA. Multivariable analysis revealed age, gender, participation in PE class, outdoor recess, and other in-school PA as independent predictors of PA. BMI and asthma status were not associated with PA. Conclusions: Children with asthma were mostly sedentary at school. Older children and girls were particularly at risk for inactivity. PE, recess, and other in-school PA participation are modifiable factors that should be targeted in school-based interventions aimed at increasing PA in this population.
The uppermost mantle beneath the Kenya dome and relation to melting, rifting and uplift in East Africa

We compare new results on S‐wave delays and P wave tomography to characterize the rising limb and melt zone of an inferred mantle convection cell beneath the Kenya dome. These results are extended to the Nyiragongo and Ethiopia domes using long wavelength gravity and topography. We suggest that the east African rift results from separation of deeper mantle upwelling into three currents that impinge on and erode the base of the lithosphere. Their thermal buoyancy drives the domal uplift, whereas brittle failure of the upper lithosphere forms the rift grabens.
A model study of the energy and mass balance of Chhota Shigri glacier in the Western Himalaya, India

Abstract. The impact of climate change on Himalaya mountain glaciers is increasingly subject of public and scientific debate. However, observational data are sparse and important knowledge gaps remain in the understanding of what drives changes in these glaciers' mass balances. The present study investigates the glacier regime on Chhota Shigri, a benchmark glacier for the observation of climate change in the monsoon-arid transition zone of Western Himalaya. Results of an energy-balance model driven by reanalysis data and the observed mass balances from three years on 50 m altitude intervals across the glacier display a correlation coefficient of 0.974. Contrary to prior assumptions, monsoon precipitation accounts for a quarter to a third of total accumulation. It has an additional importance because it lowers the surface albedo during the ablation season. Results confirm radiation as the main energy source for melt on Himalaya glaciers. Latent heat flux acts as an important energy sink in the pre-monsoon season. Mass balance is most sensitive to changes in atmospheric humidity, changing by 900 mm w.e. per 10% change in humidity. Temperature sensitivity is 220 mm w.e. K−1. Model results using 21st century anomalies from a regional climate model based on the SRES A2 scenario suggest that a monsoon increase might offset the effect of warming.
EPMA U-Th-Pb monazite dating of metamorphic rocks from the Mogok Metamorphic Belt, central Myanmar

The Mogok Metamorphic Belt (MMB), situated in central Myanmar, contains an assemblage of high-grade metamorphic rocks believed to have been formed during a regional Early Eocene-Oligocene metamorphic event. We newly found Grt-Opx granulite in the Mogok area, which was formed under pressure-temperature (P-T ) conditions estimated as being 6.5-8.7 kbar and 800-950 °C. Based on the results of EPMA U-Th-Pb Mnz dating, the central MMB, which runs through the Mogok, Mandalay, and Meikthila areas, is characterized by an Eocene to Oligocene deformation and fluid infiltration event. In addition, several Mnz grains from the Meikthila and Mandalay areas record ages of the Late Triassic (~ 200 Ma) and Cretaceous (~ 80 Ma and 110 Ma) geologic events.