Miracle-dz/UniFAR-FTUs huggingface dataset:
An ocean general circulation model view of the glacial Mediterranean thermohaline circulation

Reconstructions of the sea surface temperature and salinity of the Mediterranean Sea during the last glacial maximum (LGM) suggest that extremely cold winters occurred in the western basin and the Aegean, with highly saline conditions in the eastern basin. It is shown here that forcing the LGM Mediterranean Sea with a representative paleoclimate model results in significantly less extreme salinity conditions than are suggested by existing reconstructions. Modeled sea surface salinities are, at most, 0.1–0.2 ‰ higher than today at the LGM, rather than the previously suggested 2–3 ‰. Modeled sea surface temperatures over the western basin, however, show similar changes to these reconstructions, being 3°–4°C colder than present day. Another major difference between the LGM and control simulations is the location and spreading of subsurface water. The western basin suffers complete loss of stability in the LGM winter, leading to this basin becoming the source for the LGM deep water of the eastern basin. The ocean general circulation model results are shown to be qualitatively consistent with cooler, drier climate along the northern coast of the Mediterranean but not with higher surface salinity, thus refining existing paleoclimate reconstructions in the Mediterranean region.
Wave-Breaking Characteristics of Northern Hemisphere Winter Blocking: A Two-Dimensional Approach

AbstractThis paper generalizes and applies recently developed blocking diagnostics in a two-dimensional (2D) latitude–longitude context, which takes into consideration both mid- and high-latitude blocking. These diagnostics identify characteristics of the associated wave breaking as seen in the potential temperature θ on the dynamical tropopause, particularly the cyclonic or anticyclonic direction of wave breaking (“DB index”) and the relative intensity (“RI index”) of the air masses that contribute to blocking formation. The methodology is extended to a 2D domain and a cluster technique is deployed to classify mid- and high-latitude blocking according to the wave-breaking characteristics. Midlatitude blocking is observed over Europe and Asia, where the meridional gradient of θ is generally weak, whereas high-latitude blocking is mainly present over the oceans, to the north of the jet stream, where the meridional gradient of θ is much stronger. They occur on the equatorward and poleward flank of the jet s.
Trevorite: Ni-rich spinel formed by metasomatism and desulfurization processes at Bon Accord, South Africa?

Abstract The 3.5 Ga Bon Accord Ni deposit occurs within the lowest serpentinized mafic-ultramafic lavas of the Barberton Greenstone Belt (South Africa). Though now completely mined out, it comprised a suite of rare Ni-rich minerals that led to its interpretation as either an extraterrestrial body or as an oxidized fragment of Fe-Ni alloy originating from the terrestrial core. In this study, we draw on detailed petrographic observation and mineral chemical data, as well as previous work, to re-evaluate these ideas. The balance of evidence, from thin section (<1 mm) to regional (~10s of km) scales, appears to support an alternative origin for Bon Accord, possibly as an oxidized Ni-sulfide deposit formed in association with ocean floor komatiite eruptions.
Numerical modeling of observed effective flow behavior in unsaturated heterogeneous sands

The concept of effective parameters has been introduced in recent years to represent the spatial variability of natural soils in numerical simulation models. In the present study, effective hydraulic properties of unsaturated flow were investigated for the case of a two‐dimensional heterogeneous laboratory tank. Hydraulic parameter estimates obtained from simple statistical averages, inverse procedures, and a stochastic theory were compared to effective retention and hydraulic conductivity characteristics measured for the whole tank at steady state. The applicability of the effective parameter estimates was investigated by comparing transient flow events monitored in the laboratory tank with simulated results based on those estimates. Capillary suction measurements were simulated reasonably well using several straightforward arithmetic and geometric statistical averaging approaches, whereas most averaging approaches simulated too slow a response in the outflow rate. An alternative approach involving a combination of arithmetic and geometric averaging of the measured values more closely simulated the observed relatively fast changes in outflow rate. Generally, the simulations based on the measurements of effective properties performed quite well, indicating that the fundamental concept of effective parameters may be valid for this type of heterogeneous soil system.
Poleward Heat Transport in a Barotropic Ocean Model

Abstract A barotropic ocean circulation model coupled to a mixed-layer temperature equation is used to study the poleward heat transport by the horizontal wind-driven ocean currents. Through scaling analyses, two different regimes of the heat transport are found, characterized by λ→∞ and λ→0, respectively, where λ is the ratio between the ocean advection timescale and the restoring timescale of Newtonian cooling at the air–sea interface. In the regime λ→∞, the heat transport is proportional to λ−1 and to the second power both of the basin east–west width and of the magnitude of wind stress curl. In the regime λ→0, the heat transport is proportional to λ and to the basin width, and insensitive to the magnitude of wind stress curl. The heat transport is a maximum for intermediate values of λ, and the numerical experiments show that a restoring timescale of 5 months maximizes the heat transport for a barotropic square basin 500 m deep and 400 km wide (North Atlantic size). The corresponding maximum heat tran.
High-grade basement gneisses and granitoids in Westland, New Zealand

Abstract Gneisses and granitoids are widespread in Westland, mainly as isolated hills between the Alpine Fault and the coastal plain. On the current geological map ofNew Zealand, these rocks are designated as the Tuhua Group far convenience in regional mapping; in fact this Group includes at least two tectonically distinct units. The gneisses, which include small granitoid bodies (usually migmatitic or gneissose) make up a belt, up to 10 km wide but commonly much narrower, immediately west of the Alpine Fault, from the Grey River to Whataroa. The major granitoid bodies are intrusive into Greenland Group rocks, which make up a parallel belt to the west, but extend beyond Whataroa as far as the Arawata River and probably farther south. These two belts are separated by a major fault, probably a thrust (the Fraser Fault and its projection). The gneisses are high-grade metamorphics, consisting of quartz + plagioclase + biotite ± almandine ± hornblende ± sillimanite; the almandine is relatively Mg-rich (MgO 3.5.
Bathymetry of Shatsky Rise, northwest Pacific Ocean: Implications for ocean plateau development at a triple junction

Oceanic plateaus are large igneous edifices thought to have been created by nascent mantle plumes, but owing to sparse data, their origins remain uncertain. Understanding plateau evolution is important because they are significant ocean features and may provide clues about mantle plume dynamics. We constructed a bathymetry map of Shatsky Rise, a large Pacific plateau, combining multibeam and wide-beam echosounder data from 87 cruises and U.S. Navy multibeam contours. The rise consists of three large, isolated volcanic edifices (massifs), surrounded by nearly normal lithosphere, a linear volcanic ridge, and a group of about 80 scattered seamounts. Massif flank slopes are typically gentle (∼1.5°) and often parallel magnetic lineations or fracture zones. The slope angles imply effusive volcanism, similar to flood basalts, whereas the rise shape suggests formation near the Pacific-Izanagi-Farallon triple junction with modification of volcano flanks by spreading-ridge tectonics. Edifice sizes and inferred ages imply a trend of decreasing volume and age from southwest to northeast. Furthermore, gaps between massifs suggest episodic volcanism. Existing data are broadly consistent with the “plume head” hypothesis wherein the largest edifice formed by massive plume head eruptions, the ridge formed from the plume tail, and the two massifs in between represent a transition. Seamounts east of the rise are morphologically distinct, which suggests that they may have been formed by a different source or mechanism than Shatsky Rise proper.
Aptian to Coniacian (Early-Late Cretaceous) palynostratigraphy of the Gustav Group, James Ross Basin, Antarctica

Abstract The Gustav Group of the James Ross Basin, Antarctic Peninsula, forms part of a major Southern Hemisphere Cretaceous reference section. Palynological data, chiefly from dinoflagellate cysts, integrated with macrofaunal evidence and strontium isotope stratigraphy, indicate that the Gustav Group, which is approximately 2.6 km thick, is Aptian–Coniacian in age. Aptian–Coniacian palynofloras in the James Ross Basin closely resemble coeval associations from Australia and New Zealand, and Australian palynological zonation schemes are applicable to the Gustav Group. The lowermost units, the coeval Pedersen and Lagrelius Point formations, have both yielded early Aptian dinoflagellate cysts. Because the overlying Kotick Point Formation is of early to mid Albian age, the Aptian/Albian boundary is placed, questionably, at the Lagrelius Point Formation–Kotick Point Formation boundary on James Ross Island, and this transition may be unconformable. Although the Kotick Point Formation is largely early Albian on dinoflagellate cyst evidence, the uppermost part of the formation appears to be of mid Albian age. This differentiation of the early and mid Albian has refined the age of the formation, previously considered to be Aptian–Albian, based on macrofaunal evidence. The Whisky Bay Formation is of late Albian to latest Turonian age on dinoflagellate cyst evidence and this supports the macrofaunal ages. Late Albian palynofloras have been recorded from the Gin Cove, lower Tumbledown Cliffs, Bibby Point and the lower–middle Lewis Hill members. However, the Cenomanian age of the upper Tumbledown Cliffs and Rum Cove members, based on molluscan evidence, is not supported by the dinoflagellate cyst floras and further work is required on this succession. The uppermost part of the Whisky Bay Formation in north-west James Ross Island is of mid to late Turonian age and this is confirmed by strontium isotope stratigraphy. The uppermost unit, the Hidden Lake Formation, is Coniacian in age on both palaeontological and strontium isotope evidence. The uppermost part of the formation appears to be early Santonian based on dinoflagellate cysts, but strontium isotope stratigraphy constrains this as being no younger than late Coniacian. This refined palynostratigraphy greatly improves the potential of the James Ross Basin as a major Cretaceous Southern Hemisphere reference section.
Severe and extensive denitrification in the 1999–2000 Arctic winter stratosphere

Observations in the 1999–2000 Arctic winter stratosphere show the most severe and extensive denitrification ever observed in the northern hemisphere. Denitrification was inferred from in situ measurements conducted during high‐altitude aircraft flights between January and March 2000. Average removal of more than 60% of the reactive nitrogen reservoir (NOy) was observed in air masses throughout the core of the Arctic vortex. Denitrification was observed at altitudes between 16 and 21 km, with the most severe denitrification observed at 20 to 21 km. Nitrified air masses were also observed, primarily at lower altitudes. These results show that denitrification in the Arctic lower stratosphere can approach the severity and extent of that previously observed only in the Antarctic.
Numerical analysis of geodynamic evolution of the Earth based on a thermochemical model of mantle convection: 3-D model

Evolution of the Earth’s mantle from a hot initial state is modelled in the Boussinesq approximation within the framework of a thermochemical model. The spatial dynamics of substance within a spherical layer is illustrated by video records. Introduction of a chemical component into intermittent (with regard for an endothermic phase transition) thermal convection facilitates the overcoming of the phase barrier, enhances nonlinearity of the dynamic process, and promotes the formation of new cycles in the evolutionary process. As a result, avalanches become more numerous in the thermochemical variant and reduce to a regional scale; therefore, it is more natural to associate them with Bertrand (rather than Wilson) cycles. A basically new result of the numerical modelling is that convection developing from an unstable hot initial state gives rise to global mantle overturns (see Animations 2, 3, 4) decaying with cooling material and remarkably correlating with data of historical geology on Wilson cycles. The inferred spatial patterns of overturns are represented by a single funnel-shaped sink and a few uprising superplumes, accounting for the origins of supercontinents, opening of oceans, and the observed asymmetry of the planet.
Mega Sporting Event Legacies: A Multifaceted Concept

The legacy of mega sporting events can be perceived in several ways. It can be seenas positive or negative, tangible or intangible, territorial or personal, intentional orunintentional, global or local, short- or long-term, sport- or non sport-related, and canalso be seen from the various event stakeholders’ perspectives. In fact, it is muchmore appropriate to talk about legacies in the plural than simply legacy. This papergives a broad overview of an often used but rarely defined concept, using examplesfrom the legacies of the Olympic and Commonwealth Games, arguably two of themost important mega sporting events. It concludes that legacy essentially is a dreamto be pursued rather than a certainty to be achieved.
Evaluation of anisotropy by shear‐wave splitting

The polarizations of three‐component shear wavetrains carry unique information about the internal structure of the rock through which they pass: specifically, commonly observed shear‐wave splitting may contain information about the orientation of crack distributions. This information cannot usually be recovered from shear waves recorded at the free surface because of interference with the interaction of the shear wave with the surface, even for nearly vertical incidence. However, shear‐wave splitting in synthetic three‐component vertical seismic profiles, in some cases, may be interpreted directly in terms of the direction of strike of vertical cracks. Because the human eye is not skilled at identifying the phase relationships between three‐component seismograms played out conventionally as parallel time‐series, the polarizations are displayed in orthogonal sections of the particle displacements to facilitate recognition and evaluation of the shear‐wave splitting. Estimating the orientations of cracks, an.
Geomorphological signature and flow dynamics of The Minch palaeo‐ice stream, northwest Scotland

Large‐scale streamlined glacial landforms are identified in 11 areas of northwest Scotland, from the Isle of Skye in the south to the Butt of Lewis in the north. These ice‐directional features occur in bedrock and superficial deposits, generally below 350 m above sea level, and where best developed have elongation ratios of >20:1. Sidescan sonar and multibeam echo‐sounding data from The Minch show elongate streamlined ridges and grooves on the seabed, with elongation ratios of up to 70:1. These bedforms are interpreted as mega‐scale glacial lineations. All the features identified formed beneath The Minch palaeo‐ice stream which was ca. 200 km long, up to 50 km wide and drained ca. 15 000 km2 of the northwest sector of the last British‐Irish Ice Sheet (Late Devensian Glaciation). Nine ice‐stream tributaries and palaeo‐onset zones are also identified, on the basis of geomorphological evidence. The spatial distribution and pattern of streamlined bedforms around The Minch has enabled the catchment, flow paths and basal shear stresses of the palaeo‐ice stream and its tributaries to be tentatively reconstructed. © British Geological Survey/Natural Environment Research Council copyright 2007. Reproduced with the permission of BGS/NERC. Published by John Wiley & Sons, Ltd.
Effects of Spatial and Temporal Variations in PBL Depth on a GCM

Abstract The effect of variations in planetary boundary layer (PBL) height on a GCM was investigated using the Yonsei University (YONU) AGCM. This GCM assumes a convective boundary layer constrained to the two lowest model levels. As a consequence of this fixed PBL height, the model tends to produce excessive mixing. In this study the authors focuse on the impact of spatially and temporally varying PBL height. In addition to stability-dependent eddy diffusivity, the model adopts both bulk mixing due to the surface heat flux and z-less mixing under stable conditions. The variable-depth PBL strongly suppressed excessive mixing so that the model bias was reduced over stable regions such as the Antarctic continent. On the other hand, vertical mixing over continents in the summer hemisphere was stronger than for the fixed-PBL version, resulting in greater rising motion and warming effects in the lower atmosphere. The variable-PBL height reduces excess precipitation over the western Pacific and East Asian monso.
The carboniferous lithostratigraphy of Southeast County Limerick, Ireland, and the origin of the shannon trough

The Carboniferous succession in southeast County Limerick, on the southeastern margin of the Shannon Trough, is Courceyan to mid-Namurian in age and over 1900 m thick. The lithostratigraphy is described in detail. Its most important aspect is the presence of two thick volcanic sequences, a Chadian one of the alkali basalt to trachyte suite and one of Asbian age dominated by limburgites and ankaramites. The associated Dinantian carbonates are of shelf or ramp facies throughout, and no fundamental division into shelf and basin facies occurs as in the Dublin and Craven Basins in early Visean times. Rapid differential subsidence between this area and the Shannon Estuary began during deposition of the late Courceyan to early Chadian Waulsortian facies but was less marked in the remaining Visean when much of the volcanic topography was preserved by rapid basinal subsidence. There was basinal inversion in the late Dinantian to lower Namurian, followed by renewed subsidence in mid-Namurian times. This contrasts with the continuous rapid subsidence of the area further west on the Shannon Estuary. This behaviour, together with a comparison of that of nearby Carboniferous basins such as the Dublin, South Munster, and Craven Basins, which lack substantial volcanic sequences, suggests an origin in a transtensional regime rather than one of simple crustal stretching.
The eastern foothills of the Eastern Cordillera of Colombia: An example of multiple factors controlling structural styles and active tectonics

We decipher the geometry, timing, and kinematics of deformation of a region in the eastern foothills of the Eastern Cordillera of Colombia. We assess the influence of inherited structural fabrics, changes in basin geometry, erosional denudation, and the characteristics of the tectonic stress field with respect to the evolution of the structural styles of the deformation front in the Eastern Cordillera. Detailed structural and geomorphic mapping of an area of ∼5000 km 2 , analysis of seismic-reflection profiles, cross-section balancing, tectonic stress-field indicators, and new apatite fission-track data are used to characterize the partitioning of Late Cenozoic deformation in the eastern foothills of the Eastern Cordillera of Colombia. During the late Miocene–Pliocene, in the Eastern Cordillera, deformation migrated from inverted master normal faults to low-elevation, low-amplitude structures in the foreland. However, this shift in the locus of deformation was not spatially uniform. The deformation front is wider in a northern sector of the Cordilleran foothills, where sedimentary units are thicker, and shortening is perpendicular to the structures. This shortening direction is identical to the direction of the greatest horizontal stress S Hmax as seen in borehole breakouts. During the late Miocene–Pliocene, basement ranges are passively uplifted by younger, more frontal thrusts. The eastern foothills of the Eastern Cordillera thus reveal a complex combination of factors responsible for the structural styles and partitioning of active deformation in an inversion orogen. Over time, the most important factor changes, from the role of inherited structural fabrics to the geometries of basin fills.
Performance assessment of tire chips–gravel mixes as leachate drainage layer material

Relative drainage performance of gravel and tire chips used alone and in different combinations were evaluated through the results of drainage plate settlement and leachate conductivity testing under incremental overburden pressure levels. Experiments were performed to assess the appropriate tire chips size (in particular aspect ratio) for their large-scale uses as leachate drainage layer material. Potential of clogging for the optimized size tire chips and their mixes with gravel of transmitting relatively “high-strength” leachate were also examined. Results showed that “small” size tire chips of aspect ratio 1 (average length 22–25 mm) are suitable for relatively lower drainage plate settlement and higher leachate conductivity values. Additionally, combinations with ds/dg = 0·25 and 0·50 (by thickness) when scrap tire chips and gravel were used as separate layers gave “lesser clogging and free drainage” up to higher vertical overburden pressure levels. Alternatively, 25% of tire chips (by weight) mixed randomly with gravel also gave lesser clogging and free drainage for relatively longer period. These findings are very useful for the proper design, performance and service life of tire chips–gravel made drainage layers.
Osservazioni biosistematiche sul genere « Polypodium » L. in Italia

Riassunto La presenza in Italia delle tre specie europee del genere Polypodium L. (P. australe Fee, P. vulgare L. s. str., P. interjectum Shivas) viene verificata su una base territoriale e numerica piu ampia (ca. 700 esemplari d'erbario, FI! , e 25 coltivati), tramite osservazioni citotassonomiche, fenologiche e fenotipiche correlate. Nel procedimento e stato tenuto conto soprattutto degli elementi distintivi di maggior utilita pratica, e tra questi e stata pure controllata la validita diagnostica di caratteri ritenuti differenziali dalla vasta letteratura europea in materia ma in misura controversa (numero delle cellule dell'anulus a parete ispessita, forma della fronda, ecc.). Risulta che il P. australe (n = 37! ), il P. vulgare (n = 74! ) e il P. interjectum (n = 111! ) sono separabili tra loro in funzione non tanto di singoli elementi, piuttosto rari e validi comunque per distinguere una sola specie per volta (parafisi, colore dell'anulus, numero delle cellule basali dello sporotecio), quanto di un compl.