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131.
132.
Jutta ZIPFEL Bradley L. JOLLIFF Ralf GELLERT Kenneth E. HERKENHOFF Rudolf RIEDER Robert ANDERSON James F. BELL III Johannes BRÜCKNER Joy A. CRISP Philip R. CHRISTENSEN Benton C. CLARK Paulo A.
De SOUZA Jr. Gerlind DREIBUS Claude
D’USTON Thanasis ECONOMOU Steven P. GOREVAN Brian C. HAHN Göstar KLINGELHÖFER Timothy J. McCOY Harry Y. McSWEEN Jr. Douglas W. MING Richard V. MORRIS Daniel S. RODIONOV Steven W. SQUYRES Heinrich WÄNKE Shawn P. WRIGHT Michael B. WYATT Albert S. YEN 《Meteoritics & planetary science》2011,46(1):1-20
Abstract– The Opportunity rover of the Mars Exploration Rover mission encountered an isolated rock fragment with textural, mineralogical, and chemical properties similar to basaltic shergottites. This finding was confirmed by all rover instruments, and a comprehensive study of these results is reported here. Spectra from the miniature thermal emission spectrometer and the Panoramic Camera reveal a pyroxene‐rich mineralogy, which is also evident in Mössbauer spectra and in normative mineralogy derived from bulk chemistry measured by the alpha particle X‐ray spectrometer. The correspondence of Bounce Rock’s chemical composition with the composition of certain basaltic shergottites, especially Elephant Moraine (EET) 79001 lithology B and Queen Alexandra Range (QUE) 94201, is very close, with only Cl, Fe, and Ti exhibiting deviations. Chemical analyses further demonstrate characteristics typical of Mars such as the Fe/Mn ratio and P concentrations. Possible shock features support the idea that Bounce Rock was ejected from an impact crater, most likely in the Meridiani Planum region. Bopolu crater, 19.3 km in diameter, located 75 km to the southwest could be the source crater. To date, no other rocks of this composition have been encountered by any of the rovers on Mars. The finding of Bounce Rock by the Opportunity rover provides further direct evidence for an origin of basaltic shergottite meteorites from Mars. 相似文献
133.
This paper presents the results of the first high-resolution spectroscopic observations of the Southern W UMa type system IS CMa. Spectroscopic observations of the system were made at Mt. John University Observatory using a HERCULES fibre-fed échelle spectrograph in September 2007. The first radial velocities of the component stars of the system were determined by using the spectral disentangling technique. The resulting orbital elements of IS CMa are: AU, AU, , and . The components were found to be in synchronous rotation taking into account the disentangled line profiles of both components of the system. The Hipparcos light curve was solved by means of the Wilson–Devinney method supplemented with a Monte Carlo type algorithm. The radial velocity curve solutions including the proximity effects give the mass ratio of the system as 0.297 ± 0.001. The combination of the Hipparcos light and radial velocity curve solutions give the following absolute parameters of the components: and . The distance to IS CMa was calculated as pc using the distance modulus with corrections for interstellar extinction. The position of the components of IS CMa in the HR diagram are also discussed: the system seems to have an age of 1.6 Gyr. 相似文献
134.
Fleurice Parat François Holtz Miloš René Renat Almeev 《Contributions to Mineralogy and Petrology》2010,159(3):331-347
The equilibrium phase relations of a mafic durbachite (53 wt.% SiO2) from the Třebíč pluton, representative of the Variscan ultrapotassic magmatism of the Bohemian Massif (338–335 Ma), have
been determined as a function of temperature (900–1,100°C), pressure (100–200 MPa), and H2O activity (1.1–6.1 wt.% H2O in the melt). Two oxygen fugacity ranges were investigated: close to the Ni–NiO (NNO) buffer and 2.6 log unit above NNO
buffer (∆NNO + 2.6). At 1,100°C, olivine is the liquidus phase and co-crystallized with phlogopite and augite at 1,000°C for
the whole range of investigated pressure and water content in the melt. At 900°C, the mineral assemblage consists of augite
and phlogopite, whereas olivine is not stable. The stability field of both alkali feldspar and plagioclase is restricted to
low pressure (100 MPa) at nearly water-saturated conditions (<3–4 wt.% H2O) and T < 900°C. A comparison between experimental products and natural minerals indicates that mafic durbachites have a near-liquidus
assemblage of olivine, augite, Ti-rich phlogopite, apatite and zircon, followed by alkali feldspar and plagioclase, similar
to the mineral assemblage of minette magma. Natural amphibole, diopside and orthopyroxene were not reproduced experimentally
and probably result from sub-solidus reactions, whereas biotite re-equilibrated at low temperature. The crystallization sequence
olivine followed by phlogopite and augite reproduces the sequence inferred in many mica-lamprophyre rocks. The similar fractionation
trends observed for durbachites and minettes indicate that mafic durbachites are probably the plutonic equivalents of minettes
and that K- and Mg-rich magmas in the Bohemian Massif may have been generated from partial melting of a phlogopite–clinopyroxene-bearing
metasomatized peridotite. Experimental melt compositions also suggest that felsic durbachites can be generated by simple fractionation
of a more mafic parent and mixing with mantle-derived components at mid crustal pressures. 相似文献
135.
Mineralogy and major-trace element geochemistry of the Haymana manganese mineralizations,Ankara, Turkey 总被引:2,自引:0,他引:2
The study area comprises Çayirli, Harapa?illari and Ortabel (ÇHO) districts in the Haymana town 25 km SW of the Ankara city. In this study, geologic setting, mineralogical and geochemical characteristics of manganese mineralizations are examined and their origin is discussed. Data were obtained from field observations, various polished and thin section determinations and chemical analyses of 25 ore samples. Major and trace element analyses were conducted with ICP-ES and ICP-MS methods at ACME Laboratories (Canada). ÇHO manganese ores are found in reddish radiolarites and partly interbedded marls of the Ankara ophiolitic melange of lower Cretaceous-upper Senonian age. In these extremely folded rocks, manganese is observed as band and lenses. All samples are composed of pyrolusite and quartz. Circular pyrolusites around the gangue form a ring texture and radiolarite ores yield spherical sections. In addition, breccia-like texture is observed between pyrolusite and quartz. Geologic setting, mineralogical and textural data indicate an exogene environment. Major and trace element abundances and correlation among them imply that ÇHO mineralizations are of hydrothermal origin and linked to the same source. Evaluation of all these data shows that ÇHO manganese mineralizations are of hydrothermal type sedimentary mineralization and they were deposited in distal part of the source. 相似文献
136.
Surface rupture and source fault of the 20 February 1956 Eskişehir earthquake have been a matter of debate that potentially
contributes towards the understanding of the active deformation and seismic risk in the highly populated NW Anatolia. Field
observations on the two fault segments (namely Kavacık and Uludere faults) in the north of the Eskişehir graben revealed evidences
of co-seismic surface rupture and mass movements during the Eskişehir earthquake. Surface rupture was observed as a 2.5m wide,
a 100m long and ca. 20 cm deep asymmetric depression in the Gümüşlü valley, 2 km east of the Uludere village. A trench dug
on this depression confirms a prominent high-angle south dipping fault (dominantly left lateral strike slip) and two faint
north-dipping antithetics as clear noticeable shear zones in organic-rich thick soil. Mass failures are particularly observed
in spring depressions filled with loose torrent and carbonaceous material in front of the fault scarp. Some rock slides of
several tens of meters in size that obviously require significantly high ground shaking were also developed on steep fault
scarps. The orientation of the principal stress tensor as deduced from the surface rupture of the Eskişehir earthquake displays
clear inconsistency with the geometry of prominent faults in the area. We concluded that this disagreement may be explained
by a curved surface rupture. The western and eastern tips of this rupture are EW trending and the probable NW-running part
in the middle would correspond to the bounding zone between two right-stepping faults. 相似文献
137.
The Soultz Enhanced Geothermal System (EGS) reservoir's response to chemical stimulation is assessed by numerical simulation of coupled thermo-hydraulic-chemical processes. To assess chemical interactions between host rocks and a mixture of HCl and HF as well as its potential effects on the Soultz EGS reservoir, new modelling efforts using the FRACHEM code have been initiated. This article presents the model calibration and results. Simulations consider realistic conditions with available data sets from the EGS system at Soultz. Results indicate that the predicted amount of fracture sealing minerals dissolved by injection of a mixture of acids Regular Mud Acid (RMA) was consistent with the estimated amount from the test performed on GPK4 well at Soultz EGS site. Consequently reservoir porosity and permeability can be enhanced especially near the injection well by acidizing treatment. 相似文献
138.
Mustafa Basaran Gunay Erpul A. Ugur Ozcan Pieter Bogman Wim M. Cornelis Donald Gabriels 《Environmental Earth Sciences》2010,61(7):1375-1384
There are various types of the windblown sediment traps developed for wind tunnel and field studies. One of the main supports
expected from these traps is in measuring surface dust concentrations to appropriately derive flux equations. The measurement
performance and accuracy of a trap is very important and depends strictly upon the physical characteristics and the behaviors
of dust grains with air flows. This paper presents the measurement results of static pressure distribution (SPD) of wind flow
around Vaseline-coated slide (VCS) catchers with an aim of finding out whether or not particle trapping efficiency (η) of
the VCS is related to the SPD. The SPD was evaluated by a wind reduction coefficient (R
c) in a series of wind tunnel experiments with different VCS settings which have different attachment configurations on a pole.
Three VCS configurations were considered: a configuration on a circular plastic pole (CPP) and two configurations on wooden
square poles (WSP1 and WSP2, respectively). Thus, the primary contribution of this work was to experimentally analyze the effect of the different attachment
configurations on the SPD, and the secondary objective was to determine the effect of the SPD on the η. It was shown that
spatial correlation and spatial pattern of the R
c were different in the surrounding area of each configuration, and ANOVA and DUNCAN tests indicated that η(s) of WSP1, WSP2, and CPP were different at the significant level of P ≤ 0.05 with the mean of 0.94 ± 0.09, 0.63 ± 0.14, and 1.13 ± 0.07, respectively. Additionally, the amount of PM20, PM40, PM60, PM80, and PM100 trapped by the configurations of WSP1, WSP2, and CPP considerably varied depending upon the particular aerodynamic circumstances associated with every configuration. 相似文献
139.
Andrea Pieroni Anely Nedelcheva Avni Hajdari Behxhet Mustafa Bruno Scaltriti Kevin Cianfaglione Cassandra L. Quave 《山地科学学报》2014,11(1):180-193
Ethnobotanical studies in the Balkans are crucial for fostering sustainable rural development in the region and also for investigating the dynamics of change of Traditional Ecological Knowledge (TEK), which has broad-sweeping implications for future biodiversity conservation efforts. A survey of local botanical and medical knowledge and practices was conducted in four mountainous villages of the Peshkopia region in northeast Albania, near the Macedonian border. Snowball sampling techniques were employed to recruit 32 informants for participation in semi-structured interviews regarding the use of the local flora for food, medicinal, veterinary and ritual purposes. The uses of 84 botanical taxa were recorded as well as a number of other folk remedies for the treatment of both humans and livestock. Comparison of the collected data with another ethnobotanical field study recently conducted among Albanians living on the Macedonian side of Mount Korab shows a remarkable divergence in medicinal plant uses, thus confirming the crucial role played by the history of the last century in transforming TEK. Most noteworthy, as a legacy of the Communist period, a relevant number of wild medicinal taxa are still gathered only for trade rather than personal/familial use. This may lead to unsustainable exploitation of certain taxa (i.e. Orchis and Gentiana spp.) and presents some important conservation challenges. Appropriate development and environmental educational frameworks should aim to reconnect local people to the perception of limitation and renewability of botanical resources. 相似文献
140.
Isabel Pôças João Gonçalves Bruno Marcos Joaquim Alonso Pedro Castro João P. Honrado 《International journal of geographical information science》2014,28(11):2356-2371
This article proposes and illustrates a practical methodological framework to evaluate the fitness for use of spatial data sets for environmental and ecological applications, focusing on user requirements for specified application contexts. The methodology is based on the use of metadata to analyze similarity between the data characteristics and the user’s needs or expectations for several quality indicators. Additionally, the concept of ‘critical factors’ is introduced in this framework, allowing users to define which quality indicators have greater importance given their own requirements or expectations and the specified application contexts. The proposed methodology further allows integrating and interconnecting the spatial data quality (SDQ) evaluation methodology with metadata geoportals in WebGIS platforms, facilitating its operation by users from non-spatial disciplines and with often limited expertise on this subject. Examples of the evaluation of fitness for use for specific application contexts within the project BIO_SOS (‘Biodiversity Multi-SOurce Monitoring System: From Space To Species’ FP7 project) are presented. By providing a prompt and straightforward evaluation tool, the proposed methodology can encourage the implementation of SDQ evaluation routines in ecological assessment and monitoring programs, promoting a more adequate use of geospatial data and ultimately contributing to well-supported policy and management decisions. 相似文献