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The inception and growth of the active Carpino-Le Piane Basin Fault System (CLPBFS; central-southern Apennines, Italy) was analysed with respect to the neighbouring Isernia and Surrounding (ISFS) and Boiano Basin (BBFS) extensional Fault Systems. 39Ar–40Ar dating showed that the BBFS was already active 649 ± 21 ka bp and that the ISFS was active at least 476 ±10 ka bp , whereas the activity of the CLPBFS started certainly later than 253 ± 22 ka bp , and very probably as recently as <28 ka bp . These ages, combined with structural data (geometry and kinematics of the fault systems), indicate that the inception and development of the CLPBFS could be strictly related to the stress changes caused by earthquakes occurring on the BBFS. 相似文献
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Pasquale Sconzo 《Celestial Mechanics and Dynamical Astronomy》1980,22(1):61-62
It is shown, based on certain simplifying assumptions, that an island the size of Greenland, drifting across the North Atlantic at 10 m/century produces a change in secular rotation T=0.01 s.Presented at the Symposium Star Catalogues, Positional Astronomy and Celestial Mechanics, held in honor of Paul Herget at the U.S. Naval Observatory, Washington, November 30, 1978. 相似文献
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The Dachang mining district is the second largest producer of Sn in China and an important source of other metals. The known mineralizations can be divided into four groups: (1) cassiterite + Cu-Fe-Pb-Zn sulfides and sulfosalts, (2) Zn-Cu skarn, (3) Sb-W veins and (4) residual and placer concentrations of Sn and Fe oxides. Most orebodies are hosted by Upper Devonian calcareous, marly and quartzitic formations in spatial association with Cretaceous Yanshanian magmatites. A characteristic feature is the occurrence of stratiform, lens-shaped orebodies which appear to represent the root zone of overlying stockwork mineralizations. The metallogeny of the district may be interpreted in terms of an Upper Devonian Sn and polymetallic concentration with subsequent remobilization and, possibly, the introduction of additional elements during the late stages of the Yanshanian magmatism. 相似文献
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André C. Colonese Giovanni Zanchetta Elisabeth Dotsika Russell N. Drysdale Anthony E. Fallick Renata Grifoni Cremonesi Giuseppe Manganelli 《第四纪科学杂志》2010,25(8):1347-1359
This paper compares stable isotope (δ18O and δ13C) records of early–middle Holocene land snail shells from the archaeological deposits of Grotta di Latronico 3 (LTR3; southern Italy) with modern shell isotopic data. No substantial interspecific variability was observed in shell δ18O (δ18Os) of modern specimens (Pomatias elegans, Cornu aspersum, Eobania vermiculata, Helix ligata and Marmorana fuscolabiata). In contrast, interspecific shell δ13C (δ13Cs) variability was significant, probably due to different feeding behaviour among species. The δ18Os values of living land snails suggest that species hibernate for a long period during colder months, so that the signal of 18O‐depleted winter rainfall in their δ18Os is lost. This suggests that δ18Os and δ13Cs values of Pomatias elegans from this archaeological succession provide valuable clues for seasonal (spring–autumn) climatic conditions during the early–middle Holocene. The δ18Os values of fossil specimens are significantly lower than in modern shells and in agreement with other palaeoclimatic records, suggesting a substantial increase of precipitation and/or persistent changes in air mass source trajectories over this region between ca. 8.8 cal ka BP and 6.2–6.7 ka ago. The δ13Cs trend suggests a transition from a slightly 13C‐enriched to a 13C‐depleted diet between early and middle Holocene compared to present conditions. We postulate that this δ13Cs trend might reflect changes in the C3 vegetation community, potentially combined with other environmental factors such as regional moisture increase and the progressive decrease of atmospheric CO2 concentration. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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