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141.
Rick A. Hagen Karsten Gohl Rainer Gersonde Gehard Kuhn David Völker V. N. Kodagali 《Geo-Marine Letters》1998,18(1):19-25
The De Gerlache Seamounts actually consist of two medium-sized guyots, with summits at depths of 350–600 m. Acoustic profiler
data show no significant sediment on these guyots. Alkaline basalts dredged from the summit of the eastern guyot yield K/Ar
ages between 20.1±1.0 and 23.2±1.2 Ma. Basement ridges and sediment-filled troughs between the guyots are associated with
the prominent gravity anomaly extending north from the Antarctic margin. This structure possibly played a role in the guyot
formation, however, the question of how the De Gerlache Seamounts are related to this gravity anomaly remains uncertain.
Received: 13 February 1997 / Revision received: 30 September 1997 相似文献
142.
Thomas P. Kersten Gürcan Büyüksalh brahm Baz Karsten Jacobsen 《The Photogrammetric Record》2009,24(126):122-138
Although the Historic Peninsula of old Istanbul was added to the UNESCO World Heritage List in 1985, complete documentation of this important area has not yet been carried out. In 2006 the Istanbul Metropolitan Municipality's Historical Environment Protection Directorate initiated the "Historic Peninsula Project", which covers an area of 1500 ha and includes approximately 48 000 buildings in crowded and frequently narrow streets. BİMTAŞ, a company owned by the Municipality, immediately started the documentation of all buildings in the project area using terrestrial laser scanning. This created the challenge of building up an efficient production environment with new high-end technology to fulfil the requirements of this project in a very short timeframe of 2 years. This paper describes the entire production environment for documentation of all buildings, detailing the frequent adaptations of the process resulting from learning on the job. Although the data acquisition and mapping environment was established in the course of production, it was always essential to optimise the technical solutions in order to meet the requirements for data quality and delivery deadlines. Only 80 ha of the required 1500 ha was completed using static scanning during the first 6 months, thus requiring a change from static to mobile terrestrial laser scanning in order to accelerate the work and to conclude the scanning phase for the remaining major area within 3 months. 相似文献
143.
144.
Clayton Munnings William Acworth Oliver Sartor Yong-Gun Kim Karsten Neuhoff 《Climate Policy》2019,19(1):92-107
Nearly every carbon price regulates the production of carbon emissions, typically at midstream points of compliance such as power plants, consistent with typical advice from the literature. Since the early 2010s however, policymakers in Australia, California, China, Japan and Korea have implemented carbon prices that regulate the consumption of carbon emissions, where points of compliance are further downstream, such as distributors or final consumers. This article identifies the pivot towards placing the point of compliance for carbon prices further downstream as an emerging international trend, describes the designs of different prices on carbon consumption around the world, and explains the various motivations of the policymakers implementing them. Findings reveal that policymakers tend to layer prices on carbon consumption on top of prices on carbon production in an effort to improve economic outcomes by addressing incomplete pass-through of the carbon price from producer to consumer, thereby facilitating more cost-effective abatement. Policymakers also use prices on carbon consumption to reduce emissions leakage or because large producers of carbon are not within their jurisdiction. The prevalence of prices on carbon consumption will likely increase as evidenced by proposals in China and Europe.
Key policy insights
The recent surge in the number of jurisdictions implementing prices on carbon consumption represents an emerging international trend.
Policymakers use prices on carbon consumption in an effort to improve economic outcomes and capture environmental benefits.
While this article offers insights that detail initial challenges and successes, whether these prices on carbon consumption actually achieve their intended goals is an academically rich topic that requires further research on individual policies.
145.
146.
Ingemar Bergelin Karsten Obst Ulf Söderlund Kent Larsson Leif Johansson 《International Journal of Earth Sciences》2011,100(4):787-804
More than 100 volcanic necks composed of basanites and melanephelinites occur in Scania, southern Sweden, at the junction
of two major tectonic lineaments, the Phanerozoic Sorgenfrei-Tornquist Zone (STZ) and the Proterozoic Protogine Zone. New
40Ar/39Ar isotope analyses of whole rock fragments of nine selected basalt necks suggest that the Mesozoic alkaline volcanism in
the Scanian province commenced earlier than previously reported and comprised three separate volcanic episodes that span a
total period of ca. 80 Myr: a first Jurassic (191–178 Ma), a second at the Jurassic/Cretaceous boundary (ca. 145 Ma), and
a final middle Cretaceous episode (ca. 110 Ma). The new results allow for precise time correlations between eruption events
in the Scanian and those in the North Sea volcanic provinces. The older, early Jurassic event in Scania is largely synchronous
with that in the Egersund Basin and the Forties field whereas the event at ca. 145 Ma is correlated with activity in the Central
Graben. These volcanic episodes also correlate in age with Kimmerian tectonic activity. Volcanic activity in the middle Cretaceous
period has also been dated in the triple junction in the North Sea and offshore in the Netherland Sector. The correlation
of basalt volcanism in Scania with the Egersund nephelinites strongly suggest that volcanism was triggered by repeated tectonic
activity along the STZ. Geochemical data of alkaline mafic rocks in the Scanian and the North Sea volcanic provinces imply
that different provinces have largely unique geochemical signatures in favour of a heterogeneous mantle in the North Sea volcanic
region. However, basalts of different generations in one and the same province cannot be readily separated on the basis of
geochemistry, suggesting that the same lithospheric mantle was the source of repeated volcanism over time in each province.
The data suggest a low degree of melting of a volatile-bearing mantle lherzolite enriched in incompatible elements with the
exception of the Forties basalts in the rift centre, produced by larger degree of melting and evolved by fractional crystallization. 相似文献
147.
Nickel-rich metasomatism of the lithospheric mantle by pre-kimberlitic alkali-S–Cl-rich C–O–H fluids
Andrea Giuliani Vadim S. Kamenetsky Mark A. Kendrick David Phillips Karsten Goemann 《Contributions to Mineralogy and Petrology》2013,165(1):155-171
Metasomatism of the lithospheric mantle sometimes produces unusual assemblages containing native metals and alloys, which provide important insight into metasomatic processes in the mantle. In this study, we describe the metasomatic enrichment of a refractory harzburgite xenolith in Ni, Fe and, to a lesser extent, Cu, Co, As and Sb. The xenolith (XM1/422) derives from the Bultfontein kimberlite (Kimberley, South Africa) and hosts Ni mineralisation that includes native nickel (Ni84.5-98.0), heazlewoodite (Ni3S2) and Ni-rich silicates (e.g. up to 37.5 wt % NiO in olivine, and 22.4 wt % NiO in phlogopite). The presence of several mineral phases enriched in alkali and volatile species (e.g. phlogopite, phosphates, carbonates, chlorides, djerfisherite) indicates that the transition metal cations were likely introduced during metasomatism by alkali-rich C–O–H fluids or alkali-carbonate melts. It is postulated that sulphide breakdown and fluid reaction with refractory mantle rocks contributed to the fluid’s enrichment in Ni and other metallic cations. The Ni-rich assemblages of xenolith XM1/422 show local chemical disequilibrium, and modelling of the Ni diffusion profiles adjacent to olivine-native nickel and olivine-heazlewoodite grain boundaries, suggests a close temporal relationship between Ni-rich metasomatism and subsequent entrainment by the kimberlite magma. However, metal-rich metasomatism has also been observed in other lithospheric mantle domains, including orogenic peridotitic massifs and the suboceanic mantle; regions unaffected by kimberlite magmatsim. As micro-scale occurrences of metallic phases are easily overlooked, it is possible that metal-rich metasomatism is more widespread in the Earth’s mantle than previously recognised. 相似文献
148.
Numerical analysis of the groundwater regime in the western Dead Sea escarpment, Israel + West Bank 总被引:2,自引:2,他引:0
Agnes Gräbe Tino Rödiger Karsten Rink Thomas Fischer Feng Sun Wenqing Wang Christian Siebert Olaf Kolditz 《Environmental Earth Sciences》2013,69(2):571-585
Water is scarce in the semi-arid to arid regions around the Dead Sea, where water supply mostly relies on restricted groundwater resources. Due to increasing population in this region, the regional aquifer system is exposed to additional stress. This results in the continuous decrease in water level of the adjacent Dead Sea. The interaction of an increasing demand for water due to population growth and the decrease of groundwater resources will intensify in the near future. Thus, the water supply situation could worsen significantly unless sustainable water resource management is conducted. In this study, we develop a regional groundwater flow model of the eastern and southern Judea Group Aquifer to investigate the groundwater regime in the western Dead Sea drainage basin of Israel and the West Bank. An extensive geological database was developed and consequently a high-resolution structural model was derived. This structural model was the basis for various groundwater flow scenarios. The objective was to capture the spatial heterogeneity of the aquifer system and to apply these results to the southern part of the study area, which has not been studied in detail until now. As a result we analyzed quantitatively the flow regime, the groundwater mass balance and the hydraulic characteristics (hydraulic conductivity and hydraulic head) of the cretaceous aquifer system and calibrated them with PEST. The calibrated groundwater flow model can be used for integrated groundwater water management purposes in the Dead Sea area, especially within the framework of the SUMAR-Project. 相似文献
149.
Assessing hyporheic exchange and associated travel times by hydraulic, chemical, and isotopic monitoring at the Steinlach Test Site, Germany 总被引:1,自引:1,他引:0
Karsten Osenbrück Thomas Wöhling Dennis Lemke Nina Rohrbach Marc Schwientek Carsten Leven Cristina Castillo Alvarez Heinrich Taubald Olaf A. Cirpka 《Environmental Earth Sciences》2013,69(2):359-372
First results of a multi-disciplinary hyporheic monitoring study are presented from the newly established Steinlach Test Site in Southern Germany. The site is located in a bend of the River Steinlach (mean discharge of 1.8 m³/s) underlain by an alluvial sandy gravel aquifer connected to the stream. The overall objective is a better understanding of hyporheic exchange processes at the site and their interrelations with microbial community dynamics and biochemical reactions at the stream–groundwater interface. The present paper focuses on the distribution of lateral hyporheic exchange fluxes and their associated travel times at the Steinlach Test Site. Water level dynamics in various piezometers correspond to the different domains of hydraulic conductivity in the shallow aquifer and confirms hyporheic exchange of infiltrated stream water across the test site. Hydrochemical compositions as well as increased damping of continuous time series of electrical conductivity (EC) and temperature at the respective piezometers confirmed the inferred distribution of hyporheic flowpaths. Mean travel times ranging from 0.5 days close to the stream to more than 8 days in the upstream part of the test site could be estimated from deconvolution of EC and δ18O–H2O data. The travel times agree well with the presumed flowpaths. Mg/Ca ratios as well as model fits to the EC and δ18O data indicate the presence of an additional water component in the western part of the test site which most likely consists of hillslope water or groundwater. Based on the mean travel times, the total lateral hyporheic exchange flux at the site was estimated to be of the order of 1–2 L/s. 相似文献
150.
Catchments as reactors: a comprehensive approach for water fluxes and solute turnover 总被引:1,自引:1,他引:0
Peter Grathwohl Hermann Rügner Thomas Wöhling Karsten Osenbrück Marc Schwientek Sebastian Gayler Ute Wollschläger Benny Selle Marion Pause Jens-Olaf Delfs Matthias Grzeschik Ulrich Weller Martin Ivanov Olaf A. Cirpka Ulrich Maier Bertram Kuch Wolfgang Nowak Volker Wulfmeyer Kirsten Warrach-Sagi Thilo Streck Sabine Attinger Lars Bilke Peter Dietrich Jan H. Fleckenstein Thomas Kalbacher Olaf Kolditz Karsten Rink Luis Samaniego Hans-Jörg Vogel Ulrike Werban Georg Teutsch 《Environmental Earth Sciences》2013,69(2):317-333
Sustainable water quality management requires a profound understanding of water fluxes (precipitation, run-off, recharge, etc.) and solute turnover such as retention, reaction, transformation, etc. at the catchment or landscape scale. The Water and Earth System Science competence cluster (WESS, http://www.wess.info/) aims at a holistic analysis of the water cycle coupled to reactive solute transport, including soil–plant–atmosphere and groundwater–surface water interactions. To facilitate exploring the impact of land-use and climate changes on water cycling and water quality, special emphasis is placed on feedbacks between the atmosphere, the land surface, and the subsurface. A major challenge lies in bridging the scales in monitoring and modeling of surface/subsurface versus atmospheric processes. The field work follows the approach of contrasting catchments, i.e. neighboring watersheds with different land use or similar watersheds with different climate. This paper introduces the featured catchments and explains methodologies of WESS by selected examples. 相似文献