Miracle-dz/UniFAR-FTUs huggingface dataset:
Shona and Discovery Aseismic Ridge Systems, South Atlantic: Trace Element Evidence for Enriched Mantle Sources

The Shona Ridge system (Shona Ridge^Meteor Rise^Agulhas Ridge^Cape Rise seamounts) and the Discovery Rise to the north have been argued to represent the surface expressions of the Shona and Discovery mantle plumes, based on enriched samples along the southern Mid-Atlantic Ridge, a single sample from Discovery Rise and tectonic reconstructions. Leg PS69 ANT XXIII/5 of the R.V. Polarstern dredged the first comprehensive suite of samples from the Discovery Rise and Shona Ridge system, comprising alkali basalt through trachybasalt to trachyandesite and trachyte. Although many samples are moderately to heavily altered [loss on ignition (LOI)1⁄4 3^10%)], some incompatible elements (Nb, Ba, Zr, Y, Hf) appear to have remained sufficiently immobile that their ratios reflect the mantle source composition. Immobile element ratios for least altered samples (LOI52%) demonstrate the geochemically enriched nature (La/Smn 42; La/Ybn 43; Zr/Nb 510; Y/Nb 52) of the underlying mantle. Samples from Discovery Rise include primitive basalt, trachyandesite and trachyte. Mafic lavas are relatively unaltered (LOI52%) and have high La/Smn (44·5), Ba/ Nb (415) and Ba/Th (4130) coupled with low Zr/Nb (56·5) and Ce/Nbn (51). In accord with data from the single previously published Discovery Rise sample, these new samples confirm that the mantle source of Discovery Rise magmatism appears remarkably similar to that giving rise to Gough Island lavas some 400 km to the north. All lavas dredged from the aseismic Shona Ridge system are geochemically enriched relative to mid-ocean ridge basalt, with least altered samples having La/Smn42, Zr/Nb510 and Y/Nb 52. They are heterogeneous in their immobile incompatible trace element ratios, and can be subdivided into four geochemical groups: Group A and B lavas (found on the Shona Ridge and Agulhas Ridge) have Ba/Nb510 coupled with Ce/Nbn51; Group C lavas (restricted to the Meteor Rise) have Ba/Nb410 with Ce/Nbn51; Group D lavas (Meteor Rise and Cape Rise) have Ba/Nb410 and Ce/Nbn41.These differences are interpreted to reflect two physical components in the mantle source region: (1) a plume component (Shona plume; Group A and B lavas) comprising deep-seated upwelling mantle, itself heterogeneous and composed of typical, geochemically enriched, ocean island basalt-like mantle (La/Smn41; Ba/Nb 510; Ce/Nbn 51), but including domains containing a recycled oceanic sediment component (Group C lavas); (2) a delaminated and recycled, metasomatized, subcontinental lithospheric mantle component, possibly rafted within the shallow convecting asthenospheric mantle, that has given rise to the Group D lavas. These new data are consistent with an earlier postulation that the Shona Ridge system represents the surface expression of an underlying mantle plume.
A kinematic model for the Late Cenozoic development of southern California crust and upper mantle

A model is presented for the young and ongoing kinematic deformation of southern California crust and upper mantle that accounts for both the known late Cenozoic geologic record and upper mantle structure. In this model, the high-velocity upper mantle Transverse Ranges anomaly is created through the convergence and sinking of the entire thickness of subcrustal lithosphere. Using typical scaling relations, we estimate this anomaly to be ∼500°C colder and 1% more dense than average southern California mantle of the same depth. We infer that subcrustal lithosphere from both sides of the convergence zone participates nearly equally in the construction of the anomaly. The low-velocity upper mantle anomaly beneath the Salton Trough region is attributed to high temperatures and 1–4% partial melt related to adiabatic decompression during mantle upwelling. Our model has crustal motions in the central Transverse Ranges region differing from mantle motions: While the subcrustal lithosphere south of the Transverse Ranges moves toward and sinks beneath the Transverse Ranges, the corresponding crust largely avoids convergence by adopting a more westerly direction of motion. The differing velocity fields necessitates of a decoupling zone immediately south of the Transverse Ranges near the Moho. We interpret the upper mantle anomalies as results of small-scale convection beneath southern California, to which we attribute much of the recent tectonic activity in the region.
Some morphometric measurements on ploughing blocks in the McGregor Mountains, Canadian Rockies

Morphology and site characteristics are described for ploughing blocks in a sub‐alpine zone of the Canadian Rockies. The ploughing block features (blocks, troughs, levees, etc.) are generally larger than those described for other parts of the world. Good correlations were found between block size and both depression size and mound height. A number of ancillary observations and measurements suggest active block movement in the study area. Copyright © 2001 John Wiley & Sons, Ltd.
Relationships between California rainfall variability and large‐scale climate drivers

Bootstrapped correlation statistics of seasonally averaged monthly rainfall anomalies for the period 1950–2012 were evaluated between a comprehensive set of Atlantic‐ and Pacific‐based large‐scale climate drivers and a group of representative stations over the state of California, United States. In line with past seminal works, the analysis showed a dominant influence of the El Niño–Southern Oscillation (Pacific Decadal Oscillation) during the wetter (drier) period, particularly to the south (north) of the state. The largest correlation magnitudes were obtained for the Southern Oscillation Index (SOI) and the sea surface temperature (SST)‐based El Niño–Southern Oscillation (ENSO) indices Niños 3 and 3.4. A point‐by‐point correlation analysis with global SSTs, principal component analysis on the Pacific SST fields and wavelet spectral decomposition all assessed the robustness of the aforementioned relationships. The point‐by‐point correlation analysis with the SSTs further revealed an overall lack of relationships between rainfall and Atlantic‐based climate drivers and suggested that Indian Ocean SSTs are weakly correlated with California rainfall. This analysis also revealed that the relationship of northern California rainfall with the Pacific Decadal Oscillation (PDO) could be attributed to warm SST anomalies confined along the North American coast during the warm phase of the PDO. Notably, the wavelet analysis applied to extended rainfall records (1900–2012) revealed that the peaks in the rainfall power spectrum for southern California during the drier period are coincident with calendar years associated with the nearby passage or landfall of tropical systems in the southern California/North Baja region rather than teleconnections with large‐scale climate drivers.
Observed Changes in Cyclone Activity in Canada and Their Relationships to Major Circulation Regimes

Abstract This study assessed the climate and trend of cyclone activity in Canada using mainly the occurrence frequency of cyclone deepening events and deepening rates, which were derived from hourly mean sea level pressure data observed at 83 Canadian stations for up to 50 years (1953–2002). Trends in the frequency of cyclone activity were estimated by logistic regression analysis, and trends of seasonal extreme cyclone intensity, by linear regression analysis. The results of trend analysis show that, among the four seasons, winter cyclone activity has shown the most significant trends. It has become significantly more frequent, more durable, and stronger in the lower Canadian Arctic, but less frequent and weaker in the south, especially along the southeast and southwest coasts. Winter cyclone deepening rates have increased in the zone around 60°N but decreased in the Great Lakes area and southern Prairies–British Columbia. However, extreme winter cyclone activity seems to have experienced a weaker increa.
A mechanism for heavy precipitation over the Kii Peninsula accompanying Typhoon Meari (2004).

An extremely heavy precipitation event occurred in the mountainous Kii Peninsula in Japan, associated with Typhoon Meari in 2004. A marked characteristic of this heavy precipitation was its extreme rainfall rate, more than 100 mm h-1. Another feature was that the area of precipitation was far from the storm center, more than 500 km. From radar and surface observations, it was found that the heavy rains were composed of a stationary precipitation system and two moving precipitation systems.In order to evince a physical mechanism for the precipitation systems, the event was analyzed in detail using data from cloud-resolving simulations and observations. The results demonstrated that the heavy precipitation was produced in a synergistic manner from the three precipitation systems. The following are identified as the key factors for the formation and maintenance of each precipitation system: a) elimination of vertical convective instability in a low-level warm and moist easterly on the eastern slope of the mountainous region, b) moisture supply due to a low-level confluent flow along the boundary between the low-level easterly and south-easterly flow, and lifting of a slightly warmer south-easterly flow, and c) low-level convergence due to cold pool, running nearly parallel to the rainband axis and located slightly to the southwest of the band, acting as an obstacle to the low-level inflow into the system.Precipitation efficiency revealed that precipitation was enhanced when moving precipitation systems merged with the stationary precipitation system. The enhancement was attributed to the greater rate of conversion of cloud water to rainwater via accretion of cloud water by rain, under the condition of intense water vapor flux convergence. The moving precipitation systems provided raindrops for the accretion of cloud droplets in the stationary precipitation system. Based on our findings, extremely heavy precipitation in the present case is caused by the enhancement of the accretion process due to the merger of precipitation systems in addition to precipitation in each system.
Comparison of a Lattice‐Boltzmann Model, a Full‐Morphology Model, and a Pore Network Model for Determining Capillary Pressure–Saturation Relationships

Effective hydraulic properties of porous media such as the capillary pressure–saturation relation and the hydraulic conductivity function are a direct manifestation of the underlying pore geometry. The porous structure of a macroscopically homogeneous porous medium (sintered glass) was measured in detail using X‐ray microtomography. We investigated the possibility of deriving the water characteristic on the basis of structure analysis. We compared three approaches differing in the amount of required input data, the effort of data processing, and their predictive potential. With increasing complexity, these were (i) a simple pore network model based on a few structural parameters and a simplified process model, (ii) a direct simulation of the pressure–saturation relation based on the full morphology of the porous structure together with a simplified process model, and (iii) Lattice‐Boltzmann (LB) simulations based on the full morphology of the porous structure and modeling the complete multiphase fluid dynamics. We found that the network model, the most simple approach, may be sufficient for estimating the main drainage curve, thus suggesting that the complex pore structure can be reduced to a small set of geometric properties. If dynamic effects are considered, the LB approach provides a reliable representation, but at the cost of substantial computational efforts. Since very thin water films exist in the dry range, the continuity of the water phase cannot be described correctly with the LB approach, which presently uses uniform grids.
A Model for an Analytic−Deliberative Process in Risk Management

How can and should risk managers collect public preferences, integrate public input into the management process, and assign the appropriate roles to technical experts, stakeholders, and members of the public? Which concerns are legitimate for being used in decisions that may determine the life or death of many people? There are no simple answers to these questions. This paper discusses the potential and requirements for an analytic−deliberative decision making process in the field of risk management. It articulates the requirements for integrating analytic reasoning with deliberation and interpretation. As a result of these requirements a model of participation is developed that attempts to meet two major objectives: first, to enhance the competence in the decision making process and, second, to assign a fair share of the responsibility of managing risks to those who are or will be affected by the potential consequences. The model, named cooperative discourse, consists of three major steps: elicitation .
Clues of postseismic relaxation for the 1915 Fucino earthquake (central Italy) from modeling of leveling data

We study five high precision leveling lines located around the epicentral area of 13 January 1915, Mw = 6.7 Fucino earthquake (Italy), that possibly recorded late stage postseismic relaxation movements. The geodetic signal is expected to comprise both large‐scale uplift of the Apennines and postseismic relaxation effects. In order to verify this hypothesis and to estimate the amount of each contribution, we compute gravitational visco‐elastic postseismic relaxation by inverting leveling data. Results indicate that the elastic upper crust is relatively thin (about 10 km) and post‐seismic contribution could be set at 30% of the geodetic signal. Model parameters are consistent with previous knowledge of the 1915 Fucino earthquake source, local seismic hypocentral determinations and crustal models derived from surface waves.
Paleogeographic Development of South America

The post-Proterozoic geologic history of South America was controlled by the distribution and interplay of certain major geotectonic units, classed in five groups, which form the structural framework of the continent: cratons (Guiana, Central Brazilian, and Coastal Brazilian shields), intercratonic basins (Amazonas, Parnaiba, Sao Francisco, and Parana), pericratonic basins (Llanos-Iquitos-Acre-Beni-Chaco-Pampas plains), nesocratons (Pampean Ranges, Patagonia, and Deseado massifs), and geosynclines (Andean belts). Since Early Cambrian time the cratonic and nesocratonic areas have maintained stable to substable positive tendencies, the intercratonic and pericratonic areas have shown vertical sub-stability to submobility with intermittent but decreasing subnegative tendencies, and the western geosynclinal belts have been highly mobile, deformable elements with recurrent negative tendencies, which have witnessed the main sedimentary-tecto-magmatic activity of the continent. The paleogeographic development of South America since Cambrian time is summarized in 46 maps arranged in 33 figures, covering different geological intervals. Marine, continental, and mixed or brackishwater facies are differentiated, and the main areas of volcanic and glacial accumulation are plotted. The explanatory text-essentially a list of the main areas of exposure of the different stratigraphic units--makes brief references to the main diastrophic, volcanic, and glacial episodes.
Syn-convergent exhumation implied by progressive deformation and metamorphism in the Valle dell’Orco transect, NW Italian Alps

Structural, metamorphic and geochronological data from the Valle del'Orco are best explained by an orogenic wedge model in which crustal slices from continent and ocean acted as passive blocks at different times in the Alpine orogeny. Deformation generally migrated westwards in this section, and metamorphic recrystallization at any given point was largely controlled by the pervasiveness of strain. The data suggest a dynamic crustal stacking system lasting from 70 to 35 Ma, rather than continental collision following long-lived B-type subduction, and offer a relevant and simple model for eclogite exhumation that requires exhumation of ductile shear-bounded slices within the orogenic wedge. The easternmost, internal unit of the Sesia-Lanzo Zone, the Eclogitic Micaschist Complex, was subducted and pervasively recrystallized under eclogite facies conditions during the early stages of convergence in the late Cretaceous. During the development of the major preserved structures, the eastern Eclogitic Micaschist Complex was undergoing general non-coaxial shear with an overall top-down to the east vorticity, suggesting a potential mechanism of exhuming an eclogitic 'pip'. Slices of pre-Alpine basement, the Vasario-Sparone Subunit, were incorporated into the lower (western) parts of this unit during the latest part of this phase, but do not show penetrative effects of the early Alpine deformation. They were passively folded during the early decompressional part of the P—T history, prior to the unit being juxtaposed against the underlying Gneiss Minuti Complex under blueschist-greenschist facies conditions. The Gneiss Minuti Complex itself was then recrystallized at high strain in the greenschist-facies in the latest Eocene. Fabrics developed at this stage indicate top-down-to-east extension which may have accommodated the exhumation of eclogitized Piemont oceanic material and the European continental material of the Gran Paradiso massif. Evidence of northwest-directed thrusting within the Gran Paradiso unit at the same time suggests again that the crustal block was transported on a deeper reverse-sense shear zone that presumably links to the more external thrusts now exposed to the west. High-pressure mineral lineations within the Piemont zone cannot be unequivocally assigned to either the burial or exhumation paths, but are consistent with the generally east-west transport directions observed in the structurally higher units.
Longitudinal variability of water vapor and cirrus in the tropical tropopause layer

[1] The Microwave Limb Sounder (MLS) and the Cryogenic Limb Array Etalon Spectrometer (CLAES) are both instruments on the Upper Atmosphere Research Satellite and are sensitive to water vapor and subvisible cirrus in the tropical tropopause layer. We analyze the longitudinal and vertical variations of water vapor in the tropical tropopause layer using a new version of MLS water vapor that has improved vertical resolution. The water vapor fields show similarity with subvisible cirrus and sea surface temperature (SST) on seasonal and intraseasonal timescales. The formation of cirrus is more prevalent over continental landmasses and over warm oceanic areas where the upper troposphere is also moist. The intraseasonal variability in cirrus is correlated with upper tropospheric water vapor and linked to a variability in SST of about 1°C. The incidence of cirrus increases with SST until temperatures exceed about 29°C. A further rise in sea surface temperature does not see a corresponding increase in cirrus. Similarly, the incidence of cirrus increases as 100 hPa temperatures fall, with clouds being more likely when temperatures are about 190K. At temperatures colder than this, when in situ formation of cirrus should be more likely, there is a decrease in the likelihood of finding cirrus. Thus evidence points strongly to a dominant role for the convective formation of these cirrus.
THE ROLE OF CHINCHA IN LATE PRE-SPANISH PERU

The Chincha Valley is the largest valley on the south coast of Peru.l Many years ago Max Uhle propounded a theory that, before the Inca-conquest, the cultural influence of Chincha was very extensive, covering large parts of southern Peru and reaching into Bolivia, Chile and Argentina. In support of this theory, Uhle referred to historical sources and claimed that he could see influences of the Chincha pottery style in different local styles over this entire area and even in the Inca style of Cuzco.2 Although archaeologists have long recognized that Uhle's theory involved a great exaggeration of Chincha influence, echoes of the theory are still heard-, and the situation will not be clear until we determine what, in fact, the role of Chincha was in late preSpanish Peru.3 There is both historical and archaeological evidence not available to Uhle which can be brought to bear on this problem. The historical evidence consists of scattered reference to Chincha in 16th and 17th century Spanish sources, very inadequately utilized heretofore. The archaeological evidence includes pottery and sites with monumental architecture. In interpreting the pottery evidence it is essential to be able to distinguish Chincha pottery from that of neighboring areas. It is particularly important to be able to distinguish Chincha pottery from that of Ica, because Uhle systematically confused these two local styles. The Ica style has now been studied in sufficient detail so that there is a good basis for comparison.4
Comparisons of techniques for measuring shortwave absorption and black carbon content of aerosols from biomass burning in Brazil

Six methods for measuring the shortwave absorption and/or black carbon (BC) content of aerosols from biomass burning were compared during the Smoke, Clouds, and Radiation-Brazil (SCAR-B) experiment. The methods were the optical extinction cell (OEC), integrating plate (IP), optical reflectance (OR), particle soot/absorption photometer (PSAP), thermal evolution (TE), and remote sensing (RS). Comparisons were made for individual smoke plumes and for regional hazes dominated by smoke. Taking the OEC as a primary standard, measurements of the absorption coefficient (σa) showed that the OR method had the lowest uncertainty (17%) in σa. The other optical methods had uncertainties ranging from 20 to 40%. However, with sufficient sample size, the values of σa derived from the optical methods converged to within 20% of each other. For biomass burning aerosols in regional hazes over Brazil, this led to systematic differences of ±0.02 in the values of the single-scattering albedo derived from the various in situ techniques. It was found also that the BC content of the aerosol and σa were poorly correlated. This is likely due to a large uncertainty in the BC content of the aerosol measured by TE, and/or a high variability in the mass absorption efficiency of BC in biomass burning aerosol. Hence there is a high uncertainty in inferring σa from the BC content of smoke aerosol.
Influence of supraglacial debris on summer ablation and mass balance in the 24k glacier, southeast tibetan plateau

Abstract. Many temperate glaciers in the southeast Tibetan Plateau are covered by supraglacial debris in the ablation area. To evaluate the effect of such debris on summer ablation and mass balance, the surface ablation on the 24K Glacier was measured in the summer of 2008. Mean ablation rates varied from 10 to 52 mm/day, strongly correlated to debris thickness. Synchronous observations of air temperature allowed application of a simple degree‐day model to calculate ablation rates. Maximum values of both ablation rate and degree‐day factors appeared in the middle area of the glacier where the debris layer thickness was about 1 cm. The simulated daily ablation obtained from the degree‐day approach showed that the debris layers significantly affected the total summer ablation. The calculated ablation would be increased by 36% of the total ablation with the actual surface debris cover if glacier surface had been assumed to be entirely debris free. If completely covered by 65 cm thick debris in the ablation area, the glacier would experience a 59% decrease in summer ablation. The presence of a debris cover also leads to a change in the ablation gradient in the ablation zone.