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Distribution and sources of aliphatic hydrocarbons in surface sediments of Sergipe River estuarine system 总被引:1,自引:0,他引:1
The assessment of aliphatic hydrocarbons was performed in the Sergipe River estuarine system, northeastern Brazil. Aliphatic hydrocarbons concentration ranged from 9.9 ug g?1 up to 30.8 ug g?1 of dry sediment. The carbon preference index (CPI, based on nC?? to nC?? range), indicated predominance of petrogenic input in two of the sites analyzed (P4 and P5). The unresolved complex mixture (UCM) was found to be present in seven of the nine sites sampled (except for P4 and P5). Overall, the results of this work suggest that there is a mix of organic matter sources to the sediment. Although the coast of Sergipe has an intense off shore petroleum exploration and the Sergipe River crosses the entire city of Aracaju, the capital city of Sergipe, non-significant anthropogenic fingerprint was assessed. 相似文献
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Emö Márton 《Earth and Planetary Science Letters》1982,57(1):182-190
The pelagic limestones exposed at Sümeg appear to represent continuous deposition from Kimmeridgian through Berriasian. Detrital magnetite and haematite pigment are the carriers of remanence in the red and non-red limestones in the lower part, while magnetite becomes predominant in the upper half of the section. Thermal demagnetization has succesfully removed overprint magnetizations, and a well-defined magnetic stratigraphy has been obtained. The Late Jurassic/Early Cretaceous mixed polarity interval is correlated with the sequence of geomagnetic reversals derived from oceanic magnetic anomalies. 相似文献
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Mrton Lszl Fodor Bogomir Jelen Pter Mrton Helena Rifelj Renata Kevri 《Journal of Geodynamics》2002,34(5)
Combined paleomagnetic and structural research was carried out in the Mura-Zala Basin including the western and southern surrounding hills in northeastern Slovenia. The Mura-Zala Basin was formed due to ENE–WSW trending crustal extension in the late Early Miocene (18.3–16.5 Ma). First, marine sedimentation took place in several more or less confined depressions, then in a unified basin. During thermal subsidence in the late Miocene deltaic to fluvial sediments were deposited. After sedimentation, the southernmost, deepest depression was inverted. Map-scale folds, reverse and strike-slip faults were originated by NNW–SSE compression. This deformation occurred in the latest Miocene–Pliocene and is reflected also in the magnetic fabric (low field susceptibility anisotropy). After this folding, the Karpatian sediments of the Haloze acquired magnetization, then suffered 30° counterclockwise rotation relative to the present north (40° counterclockwise with respect to stable Europe). This Pliocene (Quaternary?) rotation affected a wide area around the Mura-Zala Basin. The latest Miocene to Quaternary folding and subsequent rotation may be connected to the counterclockwise rotation of the Adriatic microplate. 相似文献
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Emö Márton Balázs Bradák Marta Rauch-Włodarska Antek K. Tokarski 《Studia Geophysica et Geodaetica》2010,54(1):121-134
AMS studies earlier carried out on the flysch sediments from the Outer Western Carpathians focused on the sandstone members
deposited from turbidity currents. The main conclusion of these studies was that the dominant features of the AMS fabric developed
during sedimentation and the tectonic overprint was weak. In recent years a large number of claystone (deposited also from
turbidity currents, but in calm water) localities were sampled from the Krosno beds of the Silesian nappe, primarily for paleomagnetic
study. Nevertheless, the AMS of the samples was also measured. The magnetic fabrics of the claystones were dominated by foliation,
but lineations were also expressed and attributed to deformation. The question arose how different are the reactions of the
claystone and the siltstone beds to deformation. 相似文献
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Geochemical,mineralogical and magnetic characteristics of vertical dust deposition in urban environment 总被引:1,自引:0,他引:1
Péter Sipos Emő Márton Zoltán May Tibor Németh Viktória Kovács Kis 《Environmental Earth Sciences》2014,72(3):905-914
Studies on composition and distribution of dust deposition are necessary for the risk assessment of dust to atmospheric quality. We studied the vertical distribution pattern of dust and metal (Cu, Fe, Pb, Zn) deposition up to 33 m height in urban environment. Integrated geochemical, mineralogical and magnetic study of the seasonally sampled dust helped to specify our knowledge on the use of magnetic susceptibility for tracking its deposition. Harmful dust and metal deposition may occur even at great heights and at the low-traffic side of buildings. Re-suspension of local surface materials dominates the dust deposition primarily in summer and spring due to weather conditions, and it may overwrite the influence of recent anthropogenic activities on dust composition. The accepted air-flow models should be modified by taking the local conditions (weather, morphology, etc.) into account. All studied metals showed strong enrichment in the dust and could be characterized by similar vertical deposition pattern to dust. The total susceptibility was found to be much more useful proxy for tracking dust and metal deposition than mass-specific susceptibility. Using the former, potential errors arising from sampling practice of settled dust could be eliminated. The most important heavy-metal-bearing phases were iron oxides and clay minerals. Their different behavior during the dust deposition is reflected by the vertical metal distribution patterns. Clay minerals originate primarily from re-suspension and may be one of the most important sources of potentially mobile heavy metals in such materials. 相似文献
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Jacek Grabowski János Haas Emö Márton Andrzej Pszczółkowski 《Studia Geophysica et Geodaetica》2010,54(1):1-26
Jurassic-Cretaceous sediments of Transdanubian Range in Northern Hungary mostly retain their primary magnetizations and are
suitable for detailed bio- and magnetostratigraphic studies. The Lókút section, 13 m in thickness, is localized in the central
part of the Transdanubian Range. It contains the Jurassic/Cretaceous boundary in pelagic carbonate facies. Although the colour
of the rocks changes from reddish-pinkish in the bottom to almost white at the top of the section, magnetite was identified
as a magnetic carrier without evidence of hematite. Integrated bio- and magnetostratigraphical investigations resulted in
construction of chronostratigraphical scheme. The section, embraces magnetozones from M21r to M18r, of upper Lower Tithonian
(Parastomiosphaera malmica Zone) to Lower Berriasian age (Calpionella alpina Subzone). Sedimentation rate of pelagic limestones
increased from 1–3 m/My during Tithonian to 5–7 m/My during Berriasian. The sedimentation rate and its changes up the section
are comparable to those from the Jurassic/Cretaceous boundary sections of Trento plateau (Southern Alps, Italy) — sedimentary
environments of Trento plateau and central Transdanubian Range in that time might be similar. Sedimentation rate within Umbrian
Apennine basins and Križna unit in the Western Tatra Mts. seems significantly higher. Analysis of rock magnetic parameters
reveals that detrital input was much lower into the Lókút section than into Križna basin in the Tatra Mts. (Zliechov trough).
Increase of sedimentation rate occurs in both sections in the Upper Tithonian — Lower Berriasian. It coincides with the onset
of calpionellid limestone facies and is related to increased productivity of calcareous micro- and nannoplankton. Detailed
correlation of both sections basing on rock magnetic parameters and susceptibility changes is, however, not possible. They
are dependent mostly on the local sedimentary conditions (Bakony Mts. — deep water plateau; Križna unit — deep water trough)
and correlation with any “global” paleoenvironmental (climatic, eustatic) trends is not straightforward. 相似文献
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Pozsgai Emília Józsa Sándor Dunkl István Sebe Krisztina Thamó-Bozsó Edit Sajó István Dezső József von Eynatten Hilmar 《International Journal of Earth Sciences》2017,106(6):2005-2024
International Journal of Earth Sciences - The Tisza Megaunit in the Southern Pannonian Basin formed part of the southern margin of the European Plate in the Early Mesozoic era. Its exact... 相似文献