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1.
Veli‐Pekka Salonen Julien Moreau Outi Hyttinen Kari O. Eskola 《Boreas: An International Journal of Quaternary Research》2014,43(3):627-638
Finnish Lapland is known as an area where numerous sites with sediments from Pleistocene glacial and interglacial periods occur. Recent sedimentological observations and dating call for reinterpretation of the record, which shows a complicated Mid‐Weichselian ice‐sheet evolution within the ice‐divide zone. Here, a large, previously unstudied section from a former Hannukainen iron mine was investigated sedimentologically and dated with optically stimulated luminescence (OSL). Ten sedimentary units were identified displaying a variety of depositional environments (glacial, glaciolacustrine, fluvial and aeolian). They are all – except for the lowermost, deeply weathered till – interpreted to be of Mid‐ or Late Weichselian/Holocene age. Five OSL samples from fluvial sediments give ages ranging from 55 to 35 ka, indicating two MIS 3 ice‐free intervals of unknown duration. The Mid‐Weichselian interstadial was interrupted by a re‐advance event, which occurred later than 35 ka and caused glaciotectonic deformation, folding and stacking of older sediments. This new evidence emphasizes the importance of the Kolari area when unravelling the complex Late Pleistocene glacial history of northern Finland and adjacent regions. 相似文献
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Prof. Dr. Pentti Eskola 《International Journal of Earth Sciences》1960,50(1):105-123
Zusammenfassung Die Granitentstehung wird mittels Beispielen aus dem archäischen Grundgebirge Finnlands erläutert. Hier ist ein tief denudierter Horizontalschnitt durch wenigstens zwei Orogene verschiedenen Alters entblößt. Nach J. J.Sederholm werden vom Areal des Landes 78,3% von granitischen Gesteinen einschl. Migmatiten unterlagert. Davon sind 4% epirogene Granite, wie Rapakivi. Weil das Alter des Grundgebirges nach unserem heutigen Wissen mehr als die Hälfte der geologischen Zeit beträgt, kann man nicht ohne weiteres versichert sein, daß die Granitentstehung während der ältesten Zeiten quantitativ oder qualitativ ähnlich gewesen ist wie später. Es wurde in der Tat gefunden, daß bei der karelidischen Orogenese in archäischer Zeit eine Regeneration der Granite in viel größerem Maßstab stattgefunden hat als jemals während der jüngeren Orogenesen. 相似文献
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Pentti Eskola 《Contributions to Mineralogy and Petrology》1964,10(2):260-262
Ohne Zusammenfassung
Herrn Prof. Dr.Carl W. Correns zum 70. Geburtstag gewidmet. 相似文献
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Pentti Eskola 《International Journal of Earth Sciences》1936,27(1):61-73
Ohne Zusammenfassung 相似文献
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Pentti Eskola 《International Journal of Earth Sciences》1942,32(4-5):401-414
Ohne Zusammenfassung 相似文献
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P. Eskola 《International Journal of Earth Sciences》1942,32(4-5):701-702
Ohne Zusammenfassung 相似文献
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P. Eskola 《International Journal of Earth Sciences》1936,27(3):293-297
Ohne Zusammenfassung 相似文献
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A solution based on Tabarovskii's coupled pair of surface integral equations is given for the potential of a direct current flowing in an electrically anisotropic body and within the enclosing isotropic surroundings. The sources of the secondary potential exterior and interior to the body are fictitious surface charge distributions. The equations are solved numerically using point matching with pulse functions as subsectional basis functions. The model used in the applications is a long prism, excited by long line current electrodes aligned parallel to the strike. The strike length is set at a length sufficient to guarantee 2D behaviour of the model. Comparisons of computation results indicate that for the models, electrode arrays and numerical procedures applied, the solutions based on fictitious surface sources converge faster and behave more regularly than those based on real surface charges. When compared with previously published integral equation solutions, the present solution seems to be relatively efficient, even in the case of purely isotropic models. The model experiments also showed that at moderate resistivity contrasts, the anomaly shapes are strongly dependent on the directions of the principal axes of the body resistivity. However, when the external resistivity is more than 100 times that of the geometric mean of the principal resistivities in the body, with the principal resistivities differing from each other by at most one order of magnitude, the contribution of the anisotropy to the anomaly diminishes as a result of electrical saturation. 相似文献