Miracle-dz/UniFAR-FTUs huggingface dataset:
Petrogenesis of Maobei rutile eclogites from the southern Sulu ultrahigh‐pressure metamorphic belt, eastern China

The Maobei complex in the southern Sulu ultrahigh‐pressure (UHP) metamorphic belt, eastern China, mainly consists of layered eclogites, garnet peridotites and orthogneisses. Based on the modal mineral and whole‐rock compositions, eclogites from the Maobei complex are divided into quartz eclogite, quartz‐rich eclogite, rutile eclogite, rutile‐rich eclogite and eclogite. The distinct spatial changes in the lithology and related chemical compositions indicate that this complex includes 10 rhythmic layers. The rutile eclogites have high TiO2 (2.4–5.9 wt%), commonly coupled with high P2O5 (up to 4.1 wt%) contents; most show fractionated REE patterns with slight positive Eu anomalies. The rutile‐rich eclogites have very high TiO2 (3.3–5.7 wt%), FeOT (17.5–25.3 wt%), V (126–1163 ppm) and Co (14–132 ppm), and very low SiO2 (38.0–42.3 wt%), Zr (24–85 ppm), Nb (0.3–6.9 ppm), Ta (<0.1–0.6 ppm) and total REE (10.7–334.0 ppm) contents, variable degree of LREE depletion, and positive Eu anomalies (Eu/Eu* = 1.1–2.9), and the Ti is decoupled from other high‐field‐strength elements. These characteristics are consistent with Fe‐Ti gabbros of typical layered intrusions, implying a cumulate of plagioclase, clinopyroxene and abundant accessory magnetite in an evolved basaltic magmatic chamber. Based on a normal stratigraphic sequence, the Maobei complex shows an iron‐enrichment trend, followed by alkaline enrichment with increasing fractionated crystallization and stratigraphic height. These facts, together with SHRIMP U‐Pb zircon ages of 773.7 ± 8.0 Ma, indicate that the protolith of the Maobei complex is a Neoproterozoic layered intrusion consisting of a base of peridogabbro, a main body of gabbro and minor granodiorite. Unusually high Ti, V and P contents in three rutile eclogite layers suggest that they are potential economic ore deposits.
Chloritoid‐bearing rocks associated with blueschists and eclogites, northern New Caledonia

Chloritoid-bearing metasedimentary rocks occur in close proximity to blueschists and eclogites in the Tertiary high-pressure metamorphic belt of northern New Caledonia. The typical assemblage of chloritoid-bearing rocks in the epidote zone is quartzchlorite-muscovite-garnet-chloritoid. In the omphacite zone, epidote is an additional member of the chloritoid-bearing assemblage. Paragonite is rare, plagioclase was not detected, and rutile and ilmenite are the Fe-Ti oxide phases. Chloritoid-glaucophane is not a common assemblage. Chloritoid-bearing rocks have relatively low (Ca+K+Na)/Al ratios and the chloritoids are relatively Mg-rich with Mg/ (Mg+Fe) up to about 0.4. A comparison of the mineral assemblages and mineral chemistry with experimental and computed phase equilibria suggest an upper temperature limit near 560° C in the omphacite zone and a minimum temperature limit near 450° C at 10 kbar. An empirical garnet-chlorite Fe-Mg exchange thermometer does not yield consistent results for the higher-grade rocks, suggesting Ts ranging from 390 to 535° C in the omphacite zone and 420–465° C in the epidote zone. The distribution coefficient KD= (Fe/Mg)ctd/(Fe/Mg)chl for chloritoid and chlorite ranges from 3.9 to 6.4, values which are lower than those (=10) from lower greenschist facies rocks, but are near those of upper greenschist facies and albite-epidote amphibolite facies.
Coeval biochemical and biophysical weathering processes on Quaternary sandstone terraces south of Rabat (Temara), northwest Morocco

Despite numerous investigations on substrate‐inhabiting microflora, especially lichens, very little is known about the colonization of coastal escarpments by lithobiontic micro‐organisms, inland of a retreating coastline in Africa. Reported herein are the results of a combined field observation and microscopy study focusing on the connection between microrelief of the substrate, colonies of lithobiontic micro‐organisms (in particular the lichen Xanthoria parietina) and microstructures of putative bacterial origin. The occurrence of weathering pits in which the early stages of the biotic development occurs, and the subsequent disintegration of the rock indicate that lichens, mosses and fungi act synergistically by alternating chemical and mechanical weathering. Penetration of grains by expansion and contraction of the hyphae depletes the rock matrix and contributes to the mechanical breakdown of the rock. Calcite rhombs on the weathered surfaces of the calcite‐cemented sandstones are severely etched with well‐developed rhomb‐shaped etch pits (‘spiky calcite’), holes, or has one or more of the faces removed, and their cores exposed and leached. Nanofilaments (c. 100–700 nm) and ‘nanomicrobial’ fruiting bodies (c. 250 nm) emanating from micropores appear to be common on affected crystalline structures. Weddellite present immediately below the thallus is a strong indicator of biomineralization.
Benthic macroinvertebrate assemblages in five central Idaho (USA) streams over a 10-year period following disturbance by wildfire

The effects of wildfire on benthic macroinvertebrate assemblages of streams in mixed-conifer forest were examined for 10 successive years following the Mortar Creek Fire of 1979. Changes in burned-catchment streams were evaluated relative to a paired set of reference-catchment streams. Taxa richness and total abundance tended to be lower in burn than in reference streams but to converge near the end of the study; increases in the final years in both burn and reference streams were associated with reduced flows due to drought. Total biomass and that of the scraper, filterer, and miner functional groups usually were greater in the burn streams. Lack of a strong relationship of macroinvertebrate metrics with weather conditions showed that factors specific to each stream also were influencing the biotic community. Mean among-year Jaccard similarity was lower for burn than for reference streams. Specific taxa responded differently to the effects of fire. Densities of disturbance-adapted forms (e.g. Chironomidae, Baetis) increased after the fire but not during the drought period of more stable flows at the end of the study; many other taxa showed the opposite response. Adverse effects of wildfire on the biotic community were largely the result of physical changes in habitat due to increased runoff. Timing and magnitude of effects differed widely among streams as a result of differences in stream size, burn severity, and specific storm or snow-melt events. Though major effects of the fire on the macroinvertebrates dissipated within 7 years, adjustment in the habitat and biotic conditions still were taking place at the end of 10 year and normal recovery patterns may have been obscured by the drought.
Association of dolerite and lamprophyre dykes, Jetty Peninsula (Prince Charles Mountains, East Antarctica)

A compositionally varied swarm of mafic dykes in the Jetty Peninsula area was emplaced about 320 Ma ago (K-Ar age). There are three major groups: Group 1 dykes range from transitional-alkaline dolerites to camptonites, Group 2 are trachydolerites, and Group 3 are diorite to quartz diorite porphyries. Group 1 dykes have very similar ratios of most incompatible elements and were derived from the same (or a very similar) enriched lithospheric mantle source region (∈Nd −0.18 to −3.05) with high Nb and Ta (i.e., OIB, ocean island basalt, characteristics). However, the presence of several distinct subgroups with different incompatible element abundances implies significantly different degrees of melting. Group 2 trachy dolerites are much more fractionated (mg 22–36), but were apparently derived from a similar, although somewhat more enriched (∈Nd −2.26 to −4.63) source. Group 3 diorites are compositionally quite distinct and may have been derived by intracrustal melting. Enrichment of the mantle source(s) of Groups 1 and 2 dykes apparently occurred about the same time as high-grade metamorphism in the area, and may have been coeval with crust formation in nearby parts of Gondwana.
Experimental and Statistical Capacity of Rubberized Continuous Deep Beams under Monotonic and Repeated Load

Continuous Deep Beams (CDBs) are highly exposed to repeated loads especially at the bridges during vehicle loads and adding rubber into it support the ductility to overcome concrete brittleness. Six Beams were designed in considering the strut tie method (STM) and tested under monotonic and repeated loads. Mathematical model for such problem has been investigated. It can be concluded that, the CDBs lose some of its ultimate capacity due to the dropping of concrete compressive strength after aggregate-rubber replacement, while an increment in the deflection could be seen due to the higher deformability of the rubcrete mix i.e., the concrete gained some flexibility after replacing. Also, the ultimate strength of the beams decreases when comparing with the static loads by 14%, 8% and 9% for conventional beam, gravel and sand replacement beams respectively. Fuzzy regression system offers a polynomial from the third degree to represent the Fuzzy data of the CDBs.
Atmospheric lifetime and global warming potential of HFC‐245fa

We describe the method used to compute the global warming potential of hydrofluorocarbon (HFC) 245fa (CHF2CH2CF3). The Atmospheric and Environmental Research (AER) two-dimensional (latitude-height) chemistry-transport model was used to calculate the atmospheric lifetime and atmospheric scale height of HFC-245fa. Assuming that reaction with OH is the only removal mechanism, the recommended rate constant from Jet Propulsion Laboratory [1997] (6.1 × 10−13 exp (−1330/T) cm3 s−1) implies a lifetime of 7.6 years and an average atmospheric scale height of 35 km in the stratosphere. Using the IR absorption cross sections for HFC-245fa and CFC-11 determined in the laboratory, the AER one-dimensional radiative-convective model was used to calculate the radiative forcing. The value for HFC-245fa is 1.14 times larger than that for CFC-11 on a mass basis and 1.11 larger on a per molecule basis. The global warming potentials for HFC-245fa (relative to carbon dioxide) are 2400, 760, and 240 (based on the values for absolute global warming potential for carbon dioxide reported by Intergovernmental Panel on Climate Change [1996]) at integration time horizons of 20, 100, and 500 years, respectively.
Non-Stationary Hours in a DSGE Model

The time series fit of dynamic stochastic general equilibrium (DSGE) models often suffers from restrictions on the long-run dynamics that are at odds with the data. Relaxing these restrictions can close the gap between DSGE models and vector autoregressions. This paper modifies a simple stochastic growth model by incorporating permanent labor supply shocks that can generate a unit root in hours worked. Using Bayesian methods we estimate two versions of the DSGE model: the standard specification in which hours worked are stationary and the modified version with permanent labor supply shocks. We find that the data support the latter specification.
Lateral podzolization in a granite landscape.

Analysis of soil pattern, especially the pattern of depletion and accumulation zones, is a powerful tool to decipher pedogenic processes at the landscape scale. To clarify the pedogenesis of a distinct pattern of podzolized soils in the cool, perhumid Black Forest (Germany) we performed a study in the forested upper part of a granitic catchment (Barhalde). From detailed soil mapping we selected a typical catena of four pedons, which were analyzed for physical (bulk densities and particle-size distribution), chemical (pH, organic C, pyrophosphate, oxalate, dithionite, and total Al, Mn, Fe), and mineralogical (clay minerals) properties. Standard mass balance calculations were modified to include a two-component system with regard to parent material. Results showed a shift from two-mica granite to granite-porphyry downslope. Soil pattern revealed podzolized soils with thick E horizons and thin spodic horizons developed in the upslope areas, whereas in downslope soils the reverse was found (thick spodic B and thin E horizons). Soil chemical and mineralogical properties were linked to soil morphology in that contents of organic C, pedogenic oxides, hydroxy-interlayered vermiculites (HIV), and pH increased from eluvial to illuvial horizons as well as from up- to downslope soils. Mass balances of Fe and Al showed negative fluxes in upslope soils and positive fluxes in downslope soils during pedogenesis. We concluded from these results that a catenary eluvial-illuvial sequence (lateral podzolization) develops as a result of upslope mobilization followed by a (partially) lateral transport and subsequent immobilization in downslope zones, probably because the base-richer parent material built up a geochemical barrier.
Crustal evolution over the last 2 m.y. at the Mid‐Atlantic Ridge OH‐1 segment, 35°N

We present the crustal and mantle velocity structure along the strike of the eastern rift mountains at 35°N on the Mid-Atlantic Ridge. These results were obtained by an inversion of ∼1800 Pg/Pn and ∼450 PmP travel times and by gravity modeling. As commonly observed at slow spreading mid-ocean ridges, thicker crust (9 km) occurs at the segment midpoint, while thinner crust (7 km) is found toward the segment ends. This along strike variation occurs primarily in the lower crust, which is 7 km thick at the segment center and 4–6 km thick at the segment ends. In contrast, the thickness of the upper crust is relatively constant along strike. At the segment ends, relatively low velocities extend for 10–15 km along strike and from the seafloor to 4 km depth. These low velocities may indicate an attenuated melt supply and/or fracturing and alteration within the shallow to mid-crust. Directly beneath a cluster of three seamounts at the segment center is a region of relatively high velocity (+0.5 km/s) in the mid-crust. This feature may correspond to a frozen magma chamber that fed the overlying volcanoes. A synthesis of these results with those from two companion experiments along the rift valley and the conjugate flank provide a detailed record of crustal accretion and evolution at this segment. Specifically, the crustal velocity structures of each flank are nearly identical, and they exhibit a thinner and 16% faster upper crust than is observed on axis. The lower crust is remarkably similar in all three settings, except for a low-velocity body on axis, which is interpreted as a partially molten zone. The maximum crustal thickness is also similar in all three profiles, but north of the segment center, zero-age crust is nearly 4 km thinner than beneath the eastern flank and 2 km thinner than beneath the western flank. These differences may indicate that segment-centered mantle upwelling varies on a timescale of ∼2 m.y.
Retrieval of red spectral albedo and bidirectional reflectance using AVHRR HRPT and GOES satellite observations of the New England region

As a prototyping exercise for the moderate-resolution imaging spectroradiometer (MODIS) albedo/BRDF product, we demonstrate the retrieval of bidirectional reflectance distribution functions (BRDFs) and red spectral albedo measures for the New England region, United States, from merged AVHRR and GOES radiances at a 1 km2 (nominal) spatial scale. These data were acquired during a 25-day period in early fall 1995. The spatial pattern of BRDF retrievals shows that urban, suburban, and interurban regions exhibit directional scattering that is well modeled by the geometric optics of shadow casting. The directional reflectance of more continuous forest areas is better described by volume-scattering mechanisms. Spectral albedos are larger in urban and suburban areas than in forested regions, as might be expected from the strong absorption of leaves in the red wave band. The red spectral albedo generally increases with solar zenith angle, as has been noted in ground measurements of broadband albedo. A number of technical limitations discussed constrain the absolute accuracy of retrieved albedos presented here, although the spatial patterns of albedo and the consistency of the BRDF shapes inspire confidence. These limitations will largely be overcome with application of our algorithm to data from the MODIS and MISR instruments on the EOS AM-1 platform.
Changes in Surface Soil Properties of Vertisols under Dryland Cropping in a Semi-arid Environment

Changes in the properties of Vertisols in the Walgett area, north-western New South Wales, under the present continuous cropping system were investigated. Soils (0-0.1 m) from four locations which had been cultivated for 8-50 years were collected and a range of physical, chemical and biological properties were measured. Adjacent native pasture soils which had never been cultivated were used for comparison. Associated with a substantial reduction in organic matter levels (up to 40%), the cultivated Vertisols were found to have higher pH, lower extractable (Bray No. 1) phosphorus, lower structural stability and lower biological activity. The increase in pH of soils under cultivation (1 : 5 soil: water) varied from 0.5 units (8.3-8.8) in a grey clay under 20 years of cultivation to 1.5 units (7.0-8.5) in a brown clay which had been cultivated for 50 years. The higher pH may be the cause of lower extractable phosphorus found in the cultivated soils. Lower biological activity was detected in all the cultivated soils when compared with adjacent pasture soils. Added carbon and nitrogen substantially increased the biological activity of all the cultivated and pasture soils; however, in three of the four soils, carbon dioxide production of the amended cultivated soil remained lower than the corresponding amended pasture soil. For Vertisols, a pasture phase may be important in preventing alkalinization as well as in maintaining P availability, in addition to the commonly recognized benefits such as maintaining soil structure and nitrogen levels.
Modelling the probability of sustained flaming: predictive value of fire weather index components compared with observations of site weather and fuel moisture conditions

We investigated the likelihood that short-duration sustained flaming would develop in forest ground fuels that had direct contact with a small and short-lived flame source. Data from 1027 small-scale experimental test fires conducted in field trials at six sites in British Columbia and the North-West Territories between 1958 and 1961 were used to develop logistic regression models for ten fuel categories that represent unique combinations of forest cover, ground fuel type, and in some cases, season. Separate models were developed using two subsets of independent variables: (1) weather variables and fuel moisture measurements taken at the site of the test fire; and (2) Canadian Fire Weather Index (FWI) system components calculated from weather observations recorded at a nearby station. Results indicated that models developed with FWI system components were as effective as models developed with site variables at predicting the probability of short-duration sustained flaming in most fuel categories. FWI system components were not useful for predicting sustained flaming in spring grass fuels and had limited usefulness for modelling the probability of sustained flaming in aspen leaf ground fuels during summer conditions. For all other fuel categories, FWI system components were highly effective substitutes for site variables for modelling the probability of sustained flaming.
Upper Permian ostracode assemblage from the Jadar Block (Vardar zone, NW Serbia)

Ostracodes from the Changhsingian (latest Permian age) in the uppermost part of the "Bitumi- nous Limestone" Formation of the Komiric Section in NW Serbia (Jadar Block, Vardar Zone) are described and illustrated. Three new species of ostracodes are introduced: Basslerella jadarensis n. sp. , Acratia ser- bianella n. sp. , and Knoxiella vardarensis n. sp. The ostracode assemblage, together with conodonts and foraminifers, is the first record of the youngest Late Permian age microfaunas from Serbia and from the cen- tral part of the Balkan Peninsula.
The influence of the el niño southern oscillation on suspended sediment load variability in a seasonally humid tropical setting: panuco basin, mexico

ABSTRACT Although large tropical rivers transport the majority of suspended sediment to the oceans, because of a lack of adequate data there have been few detailed studies of sediment transport and its relationship to drainage basin processes. This study examines sediment transport variability in the lower Panuco basin of east‐central Mexico using daily values of streamflow and suspended sediment load spanning from the late 1950s to early 1990s. These data are used to estimate sediment yield, and in considering the influence of El Niño and La Niña events on geo‐morphic processes. Annually, the Rio Panuco transports an average of 56267×103 tons of sediment. Substantial differences in sediment transport between the Rio Moctezuma and Rio Tamuin, large basins that join to form the Rio Panuco in the Gulf Coastal Plain, are related to lithologic variability. The Panuco basin has a sediment yield of 74.1 tons (km2/yr). However, sediment load varied considerably during the period of analysis due to the influence of the El Niño Southern Oscillation (ENSO). Although a number of studies have considered the hydrologic significance of ENSO events, few have systematically considered the geomor‐phic implications of both El Niño and La Niña events. Results from this study are significant because, in comparison to adjacent regions that are dominated by El Niño events, in the Panuco basin La Niña events are more significant in terms of streamflow and sediment production. In comparison to El Niño events, stream‐flow and sediment loads are 45% and 120% greater during summer La Niña events, respectively. This suggests that increases in runoff associated with wetter La Niña conditions result in disproportionate geomorphic responce. In comparison to the Tamuin basin, sediment loads are much greater in the Moctezuma basin, which illustrates that the influence of ENSO is greater in regions underlain by clastic deposits rather than limestone. This study is significant because it systematically illustrates the significance of ENSO events to geomorphic processes within a large basin located within the seasonally humid tropics.
Leaf Area Index as Vegetation Density Measure for Hydraulic Analyses

AbstractThe correct parameterization of vegetation using measurable plant characteristics is essential for reliable flow resistance estimates. This paper focuses on the impact of density and distribution of the leaf mass on the drag force. Direct drag force measurements on flexible artificial plants were conducted in a stand. The experiments were novel in that the leaf area index (LAI) was varied in two ways: (1) the distances between the plants were altered, and (2) the leaf area of the plants was doubled and tripled. In addition, the vertical leaf area distribution was examined. The drag forces depended on the leaf mass in a similar fashion regardless of the horizontal distribution of the leaf mass, but the vertical distribution had a more significant impact. Shading of the leaves slightly reduced resistance for bushy plants because the leaf mass hidden behind the frontal projected area exerted drag. The experiments confirmed LAI to be a useful measure in estimating vegetative resistance.