Miracle-dz/UniFAR-FTUs huggingface dataset:
Interhemispheric asymmetry of the high-latitude ionospheric convection pattern

The assimilative mapping of ionospheric electrodynamics technique has been used to derive the large-scale high-latitude ionospheric convection patterns simultaneously in both northern and southern hemispheres during the period of January 27-29, 1992. When the interplanetary magnetic field (IMF) Bz component is negative, the convection patterns in the southern hemisphere are basically the mirror images of those in the northern hemisphere. The total cross-polar-cap potential drops in the two hemispheres are similar. When Bz is positive and |By| > Bz, the convection configurations are mainly determined by By and they may appear as normal “two-cell” patterns in both hemispheres much as one would expect under southward IMF conditions. However, there is a significant difference in the cross-polar-cap potential drop between the two hemispheres, with the potential drop in the southern (summer) hemisphere over 50% larger than that in the northern (winter) hemisphere. As the ratio of |By|/Bz decreases (less than one), the convection configuration in the two hemispheres may be significantly different, with reverse convection in the southern hemisphere and weak but disturbed convection in the northern hemisphere. By comparing the convection patterns with the corresponding spectrograms of precipitating particles, we interpret the convection patterns in terms of the concept of merging cells, lobe cells, and viscous cells. Estimates of the “merging cell” potential drops, that is, the potential ascribed to the opening of the dayside field lines, are usually comparable between the two hemispheres, as they should be. The “lobe cell” provides a potential between 8.5 and 26 k V and can differ greatly between hemispheres, as predicted. Lobe cells can be significant even for southward IMF, if |By| > |Bz|. To estimate the potential drop of the “viscous cells,” we assume that the low-latitude boundary layer is on closed field lines. We find that this potential drop varies from case to case, with a typical value of 10 kV. If the source of these cells is truly a viscous interaction at the flank of the magnetopause, the process is likely spatially and temporally varying rather than steady state.
Source Apportionment of Air Pollution: A Case Study In Malaysia

Air pollution is becoming a major environmental issue in Malaysia. This study focused on the identification of potential sources of variations in air quality around the study area based on the data obtained from the Malaysian Department of Environment (DOE). Eight air quality parameters in ten monitoring stations for seven years (2006 – 2012) were gathered. The Principal Component Analysis (PCA) method from chemometric technique was applied to identify the source identification of pollution around the study area. The PCA method has identified methane (CH 4 ), non-methane hydrocarbon (NmHC), total hydrocarbon (THC), ozone (O 3 ) and particulate matter under 10 microns (PM 10 ) are the most significant parameters around the study area. From the study, it can be concluded that the application of the PCA method in chemometric techniques can be applied for the source apportionment purpose. Hence, this study indicated that for the future and effective management of the Malaysian air quality, an effort should be placed as a priority in controlling point and non-point pollution sources.
Improved Secondary Recovery by Control of Water Mobility

Gogarty assumes that viscosities in cores and viscometers will be the same if measured at the same shear rate. Pye points out that this assumption is only valid if non-Newtonian rheology is the only parameter. The experimental evidence does not validate this assumption. Repeated anomalies arising in hundreds of experiments have led to the conclusion that non-Newtonian flow is not the only factor. Some of the key anomalies are as follows: (1) Measured viscosities over a range of shear rates from <1 secU-1D to 1,000 secU-1D account for only a minor fraction of the R observed in cores, when compared in similar shear-rate ranges; (2) the slope of R vs flow rates in cores is always different from that expected from viscometer shear-rate measurements; and (3) most polymer solutions are non-Newtonian and many more are more shear- rate sensitive than the polymers in question, yet only a very few polymers demonstrate useful R values.
Teleseismic estimates of radiated seismic energy: The E/M 0 discriminant for tsunami earthquakes

We adapt the formalism of Boatwright and Choy for the computation of radiated seismic energy from broadband records at teleseismic distances to the real-time situation when neither the depth nor the focal geometry of the source is known accurately. The analysis of a large data set of more than 500 records from 52 large, recent earthquakes shows that this procedure yields values of the estimated energy, EE, in good agreement with values computed from available source parameters, for example as published by the National Earthquake Information Center (NEIC), the average logarithmic residual being only 0.26 units. We analyze the energy-to-moment ratio by defining Θ = log10(EE/M0). For regular earthquakes, this parameter agrees well with values expected from theoretical models and from the worldwide NEIC catalogue. There is a one-to-one correspondence between values of Θ that are deficient by one full unit or more, and the so-called “tsunami earthquakes”, previously identified in the literature as having exceedingly slow sources, and believed due to the presence of sedimentary structures in the fault zone. Our formalism can be applied to single-station measurements, and its coupling to automated real-time measurements of the seismic moment using the mantle magnitude Mm should significantly improve real-time tsunami warning.
ELASTIC SOLUTION FOR TUNNELING-INDUCED GROUND MOVEMENTS IN CLAYS

This paper presents the elastic solutions for the prediction of the tunneling-induced ground deformations for shallow and deep tunnels in the soft ground. The oval-shaped ground deformation pattern is incorporated as the boundary condition of the displacement around the tunnel section. The difference between uniform radial and oval-shaped ground deformation patterns on surface and subsurface settlements and lateral deformation is investigated. Five case studies are used to check the applicability of the proposed analytical solutions. Generally the good agreement of the predicted ground deformations can be seen with field observations for tunnels in uniform clay.
THE PRESENTATION OF SUBJECTIVE SHAPE AND ROUNDNESS DATA

SUMMARY If a modified version of the Zingg system is used particles can be subjectively classified into four shape classes. The roundness of a particle can be estimated by assessing the flat/convex/concave ratio and can then be represented as a point on a triangular net; this point can also indicate the Zingg class of the particle.
Climate change, the Hurst phenomenon, and hydrological statistics

Abstract The intensive research of recent years on climate change has led to the strong conclusion that climate has always, throughout the Earth's history, changed irregularly on all time scales. Climate changes are closely related to the Hurst phenomenon, which has been detected in many long hydroclimatic time series and is stochastically equivalent to a simple scaling behaviour of climate variability over time scale. The climate variability, anthropogenic or natural, increases the uncertainty of the hydrological processes. It is shown that hydrological statistics, the branch of hydrology that deals with uncertainty, in its current state is not consistent with the varying character of climate. Typical statistics used in hydrology such as means, variances, cross- and autocorrelations and Hurst coefficients, and the variability thereof, are revisited under the hypothesis of a varying climate following a simple scaling law, and new estimators are studied which, in many cases, differ dramatically from the classical ones. The new statistical framework is applied to real-world examples for typical tasks such as estimation and hypothesis testing where, again, the results depart significantly from those of the classical statistics.
Influence of Choice Set Considerations in Modeling the Benefits From Improved Water Quality

Random utility models have become popular tools for the measurement of economic benefits from environmental quality changes. These models, however, require assumptions about the choice sets held by the individuals in the sample. Typically, researchers specify the choice set and assume that individuals are aware of all elements of this set. This paper compares the standard approach with an alternative that uses an estimate of each sampled individual's specific choice set. The latter approach produces model parameters and welfare estimates that are quite different from those using standard assumptions.
High-precision temporal calibration of Late Permian vertebrate biostratigraphy: U-Pb zircon constraints from the Karoo Supergroup, South Africa

Therapsid and other tetrapod fossils from the South African Karoo Supergroup provide the most detailed and best studied terrestrial vertebrate record of the Middle and Late Permian. The resulting biostratigraphic scheme has global applicability. Establishing a temporal framework for these faunas has proven difficult: magnetostratigraphy has been hampered by a Jurassic overprint, and intercorrelation with Permian marine sequences has been equivocal. Here we report U-Pb zircon isotope dilution–thermal ionization mass spectrometry (ID-TIMS) dates for five volcanic ashes interbedded with fossils from the Pristerognathus , Tropidostoma , and Cistecephalus vertebrate biozones of the Beaufort Group. This temporal framework allows correlation to marine zonations and improves understanding of rates of faunal evolution and patterns of basin evolution. Our results identify no correlative vertebrate extinctions in the Karoo Supergroup to the marine end-Guadalupian mass extinction and raise the question of whether there is any record of a terrestrial extinction related to the Emeishan large igneous province.
Andean Adakite-like high-Mg Andesites on the Northern Margin of the Chilean–Pampean Flat-slab (27–28·5°S) Associated with Frontal Arc Migration and Fore-arc Subduction Erosion

Glassy, plagioclase phenocryst-free, (cid:2) 7^3 Ma, andesitic lavas erupted at the southern end of the Andean Central Volcanic Zone (CVZ) at 27^28 · 5 8 S are argued to contain a component from continental crust that was incorporated into the sub-arc mantle in a major pulse of fore-arc subduction erosion that removed (cid:2) 50 km of fore-arc.The 7^3 Ma amphibole-bearing Pircas Negras (54^64% SiO 2 ) and (cid:2) 7 · 7 Ma pyroxene-bearing Dos Hermanos lavas erupted as the frontal arc was displaced some 50 km eastward over a develop-ing bend in the Wadati^Benioff zone at the northern margin of the Chilean^Pampean flat-slab region. Their chemistry differs from that of older Miocene and younger CVZ arc lavas in the region in having more pronounced high field strength element (La/Ta ¼ 40^ 100; Ba/Ta ¼ 800^2400) and heavy rare earth element (Sm/ Yb (cid:2) 4^9) depletions and an extreme adakitic-like character ( (cid:2) 600^1400 ppm Sr; Sr/Yb (cid:2) 400^1350). They also differ from older Miocene lavas in having higher 87 Sr/ 86 Sr and lower 143 Nd/ 143 Nd at the same wt % SiO 2 , while still showing trends with increasing wt % SiO 2 that are best attributed to contamination in the (cid:2) 65^70 km thick crust. Overall, the trace element and isotopic features of the Pircas Negras lavas are consistent with modeling that attributes differences from older and younger lavas to enrichment of the arc mantle wedge by partial melts of tectonically eroded fore-arc crust, with the modeled eroded component being an outcrop and geophysically constrained mixture of 80^90% Jurassic mafic magmatic rocks and 10^20% silicic Paleozoic crust. An ada-kitic-type partial melt of this eroded crust generated at 4 2 GPa, reacted with mantle peridotite, can explain the high Mg# values (50^61) and Cr (100^350 ppm) and Ni (40^70 ppm) contents in some 5^3 Ma Pircas Negras lavas. Pre-eruption temperatures over 1060 8 C, calculated from mineral thermometry and the MELTS program, permit these magmas to subsequently melt and react with overlying eclogitic crust. Magma storage in this thick crust then led to amphibole crystallization and suppression of plagioclase fractionation. Quartz and feldspar xenocrysts were acquired from locally pooled mid-crustal magmas and the silicic upper crustal basement during final rapid ascent to the surface. Given a constant arc^ trench gap of 300 km over the last 10 Myr, (cid:2) 198 km 3 Myr ^1 km ^1 of fore-arc crust needs to be removed by subduction erosion at 8^3 Ma to account for the material balance of the fore-arc crust.
Postrift sequence stratigraphy, paleogeography, and fill history of the deep-water Santos Basin, offshore southeast Brazil

Events that influenced the Santos Basin were different from the Campos Basin to the north (where the bulk of the petroleum reserves in Brazil have been discovered) and resulted in a very different stratigraphy. Because of these differences, the Campos Basin stratigraphic model is poorly suited to the Santos Basin (cf. Cobbold et al., 2001). We divide the postrift stratigraphy of the deep-water Santos Basin into 11 major sequences, each representing an average duration of approximately 11 m.y. and encompassing the middle–Late Cretaceous and Tertiary. The complex fill history of the Santos Basin was strongly influenced by the uplift of the Serra do Mar coastal mountain ranges in the Late Cretaceous and the subsequent organization of the coast-parallel Paraiba do Sul drainage system. The ancestral Paraiba do Sul tended to focus clastic influx into the northern and central Santos Basin during the Late Cretaceous and Paleogene. Focused clastic influx forced massive shelf progradation and deep-water turbidite sedimentation despite globally high-standing sea level. The southern Santos Basin, at the same time, was relatively starved of clastic influx, and drowned shelf conditions prevailed.These depositional patterns persisted until the Oligocene, when the Paraiba do Sul was captured and diverted into the Campos Basin to the north into which it currently empties. After the capture and diversion of the Paraiba do Sul, the north-central Santos Shelf was starved and drowned, and the shelf edge backstepped more than 50 km (30 mi). The southern Santos Basin, in contrast, was buried by a thick sequence of mud-prone upper Oligocene and Neogene sediments that had a great impact on source rock maturity.
Earthquake locations using single‐station deep borehole recordings: Implications for microseismicity on the San Andreas fault in southern California

We have located and estimated source parameters of 109 earthquakes (0 to 5 M) using seismograms recorded at 2.5 km depth in the Cajon Pass borehole, southern California. The borehole is about 4 km from the San Andreas fault, at the boundary between the locked, almost aseismic Mojave and San Bernardino segments, where the San Jacinto fault approaches the San Andreas. This area is of interest both on account of its tectonic complexity and its high potential seismic hazard. The clear, relatively unattenuated downhole recordings are rotated to determine the incoming azimuth of the P wave, and the delay time between the P and S arrivals is used to estimate the hypocentral distance. The difference between the hypocenters located this way and the Southern California Seismic Network (SCSN) locations of the same earthquakes increases with hypocentral distance from the borehole. Of the earthquakes within 20 km of the borehole, 95% are within 1–2 km of the SCSN epicenters and all are within 5 km of the SCSN depths. All but three of the 58 earthquakes located here which the SCSN did not record were within 20 km of the borehole and so the location errors are similar to those of SCSN A and B quality events. Most of the small earthquakes occurred within the relatively active San Jacinto fault zone, but at least eight are located close to or within the San Andreas fault zone. The stress drops for these events range from 0.1 to 18 MPa. These earthquakes appear similar to the other events in this study suggesting that the San Andreas fault is similar to other faults at the scale of these small earthquakes. The variation in stress drop and slip orientation of these small earthquakes suggests that larger scale heterogeneity continues to these small scales. Also, the location of these small earthquakes in major established fault zones implies that earthquake source dimensions are not geometrically controlled by fault zone width.
The semi‐diurnal tide in Hudson strait as a resonant channel oscillation

Abstract Tidal studies have shown that there exists a resonance of the semi‐diurnal tide in the Hudson Bay‐Hudson Strait system. The resonant response is particularly strong within Hudson Strait and Ungava Bay. It is shown here that the semi‐diurnal tide in Hudson Strait has characteristics that are similar to those of a half‐wavelength open channel resonance. A simple analytical model is developed to account for the salient aspects of the semi‐diurnal response in the strait. Non‐dimensional parameters that govern the response are identified and evaluated based on the physical dimensions of the region and results from a numerical tidal model. Taking account of the mechanical impedance presented to the channel by Hudson Bay, the results suggest that a channel mode is resonant near semi‐diurnal periodicities, in general agreement with observations and more complex tidal models of the region. The possibility that Ungava Bay may have a separate quarter‐wavelength resonance driven at the entrance to the continental shelf is also briefly explored.
Interpretability and resolution in post‐migration time‐slices

A surprising result was that data which were acquired on an adequate spacing (as predicted by plane-wave theory) were nevertheless still improved in interpretability by interpolation onto a finer grid. In our experiments, we found that Kirchhoff migration performed a better job of interpolation than a cheaper two-pass post-migration algorithm. In this regard, we feel that the Neidell hypothesis may contain a valuable intuitive insight: specifically, that interpolation aids visual interpretability (the most important criterion for seismic data).
A COMPARISON OF LAMB CIRCULATION TYPES WITH AN OBJECTIVE CLASSIFICATION SCHEME

An objective scheme, initially developed by Jenkinson and Collison, is used to classify daily circulation types over the British Isles, along the lines of the subjective method devised by Lamb. The scheme uses daily grid-point mean sea-level pressure data for the region. The results of the analysis over the period 1881-1989 are compared with ‘true’ Lamb weather types. The frequencies of objectively developed types are highly correlated with traditional Lamb types, especially so for synoptic (cyclonic and anticyclonic) types, although still good for wind directional types. Comparison of the two classification schemes reveals negligible differences between the correlations of the counts of circulation types and regional temperature and rainfall. The major difference between the two classification schemes is that the decline of the westerlies since 1940 is less evident with the objective scheme.
Survey and analysis of vegetation and hydrological change in English dune slack habitats

Statement from Natural England: Dune wetlands have been a poorly understood component of dune ecosystems. However, the majority of England’s dunes are notified and/or designated under national and European environmental legislation. In addition, most face a range of acute and current challenges to their ecological condition. This combination has made it difficult for Natural England to effectively and efficiently carry out its statutory duties where these relate to sand dunes. The two year research programme on dune ecohydrology led by CEH for Natural England, with contributions from BGS, has resulted in a major improvement in this situation.
Soil Seed Bank of a Jack Pine (Pinus Banksiana) Ecosystem

The soil seed bank (seed and vegetative propagules) of a jack pine (Pinus banksiana Lamb.) ecosystem was investigated using direct propagule emergence from soil cores in greenhouse experiments, and visual examination of rhizome/rooting systems in situ. Of the 985 emergents observed from soil cores 643 (65%) originated from seeds whereas 342 (35%) arose from rhizomes. Grasses and sedge comprised 89% of the seed emergents while shrubs comprised 75% of the vegetative emergents. In situ examination of root systems revealed that Linnaea borealis L. , Carex houghtonii Torr. , Gaultheria procumbens L. , and Maianthemum canadense Desf. had rhizomes buried at or above the duff/mineral interface while Lycopodium obscurum L. , Lycopodium complanatum L. and Pteridium aquilinum L. (Kuhn) were predominately buried within the upper- layers of mineral soil. All other vegetatively reproducing species examined, with the exception of Rubus alleghaniensis Porter, had rhizomes buried deeper than 25 cm into mineral soil. Rubus allegheniensis (reproductive roots) had no discrete area of burial and were located in duff, upper mineral, and deep mineral soil. Depth of burial of reproductive material is used to explain plant succession after disturbance.
Spectral reflectance 0.4 to 2.0 microns of silicate rock powders.

Silicate rocks in powdered form can be classified as belonging to the broad categories of rock glasses, crystalline acidic rocks, or crystalline basic-ultrabasic rocks, on the basis of spectral reflectance properties in the 0.4- to 2.0-μ wavelength region. Distinguishing characteristics are the ratio of reflected light at 0.7 μ to that at 0.4 μ, here termed R/B, the change in R/B with albedo, the maximum albedo of a rock powder, and the occurrence of broad absorption bands in the reflectance spectrums between 0.8 and 2.0 μ. Spectral reflectance properties depend strongly on particle opacity which, in turn, is controlled by chemical composition, mineralogy, and particle size; but reflectance also is affected in a regular way by particle packing, particle shape, and illumination geometry. The experimental results have potential application in determining gross compositional trends on planetary surfaces, but they also emphasize that many variables must be considered in any geologic interpretation of spectral reflectance data.
Simulation of the Wind-Forced Near-Surface Circulation in Knight Inlet: A Parameterization of the Roughness Length

Abstract Month-long observations of along-channel velocity made close to the surface of Knight Inlet are used with a numerical model to estimate the roughness length z0 on the water side of the air–sea interface. In analogy with a very common parameterization for z0 on the air side of the air–sea interface, z0 is parameterized in the numerical model as z0 = au2∗/g where u∗ = (τ/ρ)1/2 is the friction velocity, g is the acceleration due to gravity, τ is the wind stress, ρ is the density of water, and a is an empirical constant. It is found that a ≈ O(105) for the dataset from Knight Inlet, a value four orders of magnitude larger than the value commonly used to estimate z0 on the air side of the air–sea interface. When compared to empirical estimates of the significant wave height Hs, it is found that z0 ≈ O(Hs). Further evidence is provided that a numerical model that uses the Mellor–Yamada level 2.5 turbulence closure scheme can simulate the near-surface, wind-forced circulation quite well.