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541.
Zusammenfassung Ausgehend von den regelhaften Ablaufsformen in der stammesgeschichtlichen Entfaltung werden der stammesgeschichtliche Werdegang der Hominiden und die ihn bestimmenden Umbildungstendenzen diskutiert, die vor allem durch die Cerebralisation beherrscht werden. Die Frage, ob die orthogenetisch verlaufende Fortbildung der Hominiden eine aus der Entwicklungsrichtung abgeleitete, voraussagende Projektion in die Zukunft möglich macht, muß verneint werden; denn die excessive Cerebralisation führt den Menschen aus dem biologischen Zwangsablauf heraus in eine durch Entscheidungsfreiheit gekennzeichnete Sonderstellung.
Proceeding from the regular forms of evolution of the Humanoids, the phylogenic processes involved and the controlling remodeling tendencies, dominated principally by cerebralisation, are discussed.The question whether the orthogenetic course of further evolution of the Humanoids would make it possible to predict a future image — derived from the evolutionary trends — must be negated. This follows from the fact that excessive cerebralisation leads the Human-beings out of the biological inevitable course into a special situation characterised by free judgement.
Résumé En partant des règles sur la dérivation des formes dans l'évolution phylogénétique, l'auteur discute l'évolution des Hominidés et les tendances déterminantes à la transformation, principalement dominées par la cérébralisation. A la question de savoir si la continuation orthogénétique en cours de l'évolution des Hominidés peut faire l'objet d'une prédiction en la projetant selon sa ligne directrice, on ne peut que répondre négativement: la cérébralisation excessive conduit l'homme hors des contraintes biologiques dans une position particulière caractérisée par la liberté de décision.
. , . .相似文献
542.
Karl Fuchs 《Physics of the Earth and Planetary Interiors》1983,31(2):93-118
This paper advances new evidence for elastic anisotropy in the continental subcrustal lithosphere in southern Germany. The range of petrological models compatible with the observed azimuthal variation of seismic P-wave velocity is explored. The azimuthal distribution of amplitudes of mantle phases and the observed increase of P velocity with depth both indicate a continuation of anisotropy with depth together with an increase of preferred orientation. Even depletion of the upper mantle in basaltic components, as suggested by mantle xenoliths from various parts of Germany, cannot explain the velocity-depth and azimuthal amplitude observations without an increase of anisotropy with depth.Preferred orientation of olivine is the most likely mechanism for the observed phenomena. Its fast a-axis at the Moho level is directed towards N22.5°E. The b-axis is also required to be horizontal; i.e., the b-plane, one of the preferred glide planes of olivine, is vertical, with a strike of N22.5°E. Therefore, this preferred glide plane of olivine practically coincides with the plane of maximum horizontal shear stress deduced from fault-plane solutions of earthquakes in western Germany. This is a strong indication that the preferred orientation of olivine is formed in the recent West European crustal stress field leaking into the upper mantle. The distribution of velocities to a depth of at least 50 km requires slight horizontal rotation of the a-axis with depth by ~ 10° towards N32°E, and a change in the modal composition towards a depletion increasing with depth compatible with the composition of mantle xenoliths from western Germany. Further experiments are needed to substantiate this suggestion, which could lead to a better understanding of the interaction of crustal and upper-mantle stress-strain fields. 相似文献
543.
Prof. Dr. Michael Raith Dr. Peter Raase Prof. Dr. Paul Karl Hörmann 《International Journal of Earth Sciences》1982,71(1):230-244
The Precambrian crust of northern Finland has been the subject of detailed geochemical and petrological studies. The geochemical data and the present-day geotectonic setting suggest the existence of an old island arc system with the West Inari schist zone (Tana River belt) as an outer tholeiitic arc, the granulite complex as a calcalkaline inner arc, and a stable continental block (granite gneiss complex + Kola nucleus) in the northeast.The entire terrain was affected by intense deformation and polyphase high-grade metamorphism during the Karelian orogeny (2200–1900 m.y.). The regional and temporal development of the mineral assemblages is discussed. The conditions of the postkinematic stage of metamorphism have been evaluated from mineral stability data, with methods of geothermometry and geobarometry, and by the study of fluid inclusions. Metamorphic grade was of amphibolite fades (650–750° C, 5–8 kbars, XH2O 1) in the Tana River belt and the granite gneiss complex, but of hornblende-granulite facies (700–800° C, 6–8 kbars, XH2O0.3) in the granulite complex.
Zusammenfassung Stoffbestand und metamorphe Entwicklung der präkambrischen Kruste Nordfinnlands werden auf der Basis detaillierter geochemischer und petrologischer Untersuchungen diskutiert.Die geochemischen Daten der Gesteine und die geotektonischen Verbandsverhältnisse weisen auf die Existenz eines alten Inselbogensystems hin. Die West Inari Schist Zone (Tana River Belt) kann als äußerer tholeiitischer Bogen, der Granulit-Komplex als innerer kalk-alkalischer Bogen und der Granitgneis-Komplex (mit Kola-Nukleus) im NE als stabiler kontinentaler Block aufgefaßt werden.Der gesamte Bereich wurde während der karelischen Orogenese (2200-1900 Ma) intensiv deformiert und von einer mehrphasigen hochgradigen Metamorphose erfaßt. Die regionale und zeitliche Entwicklung der Mineralparagenesen wird diskutiert. Die Bedingungen des postkinematischen Metamorphosestadiums werden anhand von Mineralstabilitätsdaten, mit geothermometrischen und geobarometrischen Methoden und durch die Untersuchung der Flüssigkeitseinschlüsse abgeleitet. Die Gesteinsserien des Tana River Belt und des Granitgneis-Komplexes liegen in Amphibolitfazies vor (650–750° C, 5–8 kb, XH2O 1), im Granulit-Komplex dagegen in Hornblende-Granulitafzies (700–800° C, 6–8 kb, XH2O<0.3).
Résumé L'origine et l'évolution métamorphique de la croûte précambrienne de Laponie sont discutées sur la base d'études géochimiques et pétrologiques.Les données géochimiques et l'aspect actuel de la disposition géotectonique indiquent l'existence d'un ancien système d'arcs insulaires, ou la «West Inari schist zone» (ceinture du Tana), représenterait un arc volcanique extérieur d'affinité tholéiitique, la ceinture des granulites étant un arc intérieur d'affinité calcoalcaline, et le «granite gneiss complex» (nucléus de l'Inarijärvi et le craton de la Péninsule de Kola), un vieux bloc continental nord-est.Ce terrain a été affecté en entier par une déformation intense et par un métamorphisme polyphase de haut degré pendant l'orogenèse carélienne (2200–1900 Ma). L'évolution régionale et temporelle des paragénèses est discutée. Les conditions de la phase postdéformative du métamorphisme ont été évaluées par application des données sur la stabilité des minéraux, par l'utilisation de géothermomètres et géobaromètres et par l'étude des inclusions fluides. Les séries de la ceinture du Tana et du nucléus de l'Inarijärvi sont caractérisées par le faciès amphibolites (650–750° C, 5–8 kb, ), tandis que la ceinture des granulites s'est développée en faciès granulite à hornblende (700–800° C, 6–8 kb, XCO2<0.7).
. , West Inri ( ) , , -, - - NE, . (2200–2900 ) . . , , . - (650–750 °, 5–8 , ), — (700– 800 °, 6–8 , XCO2 0,7).相似文献
544.
545.
Karl W. Butzer 《Quaternary Research》1974,4(2):136-148
This paper evaluates the geological and paleoecological implications of a Wenner-Gren symposium Stratigraphy and Patterns of Cultural Change in the Middle Pleistocene. The deep-sea, glacial-eustatic, loess, alluvial, and palynological records suggest between six and eight cold-warm cycles since the Brunhes-Matuyama magnetic reversal of 700,000 BP. Till and outwash stratigraphies are inadequate to provide a valid nomenclature for the numerous glacials preceding the Würm. Since at least five of the glacials since 700,000 BP were sufficiently severe to produce permafrost in midlatitude Europe, the “glacial Pleistocene” begins with the Brunhes-Matuyama. Although earlier cold-warm cycles extend well back into the early Pleistocene, with extensive glaciation and repeated floral decimations in higher latitudes, the first record of permafrost in the Rhine Basin 700,000 BP argues that major climatic oscillations of the Brunhes epoch were of glacial-interglacial amplitude. It is therefore recommended that a Lower-Middle Pleistocene boundary be linked to the practicable and universally applicable chronometric horizon provided by the Brunhes-Matuyama reversal, while the Middle-Upper Pleistocene limit can continue to be drawn at the base of the last, Eemian Interglacial (130,000 BP). The tropical African record presently contributes little to general understanding of the Middle Pleistocene, while the climatic cycles of higher latitudes are of limited value in analyzing mid-Pleistocene records of the tropical continents. Problems of stratigraphic control and environmental contexts for archeological sites are discussed. 相似文献
546.
Holocene climatic variations—Their pattern and possible cause 总被引:1,自引:0,他引:1
In the northeastern St. Elias Mountains in southern Yukon Territory and Alaska, C14-dated fluctuations of 14 glacier termini show two major intervals of Holocene glacier expansion, the older dating from 3300-2400 calendar yr BP and the younger corresponding to the Little Ice Age of the last several centuries. Both were about equivalent in magnitude. In addition, a less-extensive and short-lived advance occurred about 1250-1050 calendar yr BP (A.D. 700–900). Conversely, glacier recession, commonly accompanied by rise in altitude of spruce tree line, occurred 5975–6175, 4030-3300, 2400-1250, and 1050-460 calendar yr BP, and from A.D. 1920 to the present. Examination of worldwide Holocene glacier fluctuations reinforces this scheme and points to a third major interval of glacier advances about 5800-4900 calendar yrs BP; this interval generally was less intense than the two younger major intervals. Finally, detailed mapping and dating of Holocene moraines fronting 40 glaciers in the Kebnekaise and Sarek Mountains in Swedish Lapland reveals again that the Holocene was punctuated by repeated intervals of glacier expansion that correspond to those found in the St. Elias Mountains and elsewhere. The two youngest intervals, which occurred during the Little Ice Age and again about 2300–3000 calendar yrs BP, were approximately equal in intensity. Advances of the two older intervals, which occurred approximately 5000 and 8000 calendar yr BP, were generally less extensive. Minor glacier fluctuations were superimposed on all four broad expansion intervals; those of the Little Ice Age culminated about A.D. 1500–1640, 1710, 1780, 1850, 1890, and 1916. In the mountains of Swedish Lapland, Holocene mean summer temperature rarely, if ever, was lower than 1°C below the 1931–1960 summer mean and varied by less than 3.5°C over the last two broad intervals of Holocene glacial expansion and contraction.Viewed as a whole, therefore, the Holocene experienced alternating intervals of glacier expansion and contraction that probably were superimposed on the broad climatic trends recognized in pollen profiles and deep-sea cores. Expansion intervals lasted up to 900 yr and contraction intervals up to 1750 yr. Dates of glacial maxima indicate that the major Holocene intervals of expansion peaked at about 200–330, 2800, and 5300 calendar yr BP, suggesting a recurrence of major glacier activity about each 2500 yr. If projected further into the past, this Holocene pattern predicts that alternating glacier expansion-contraction intervals should have been superimposed on the Late-Wisconsin glaciation, with glacier readvances peaking about 7800, 10,300, 12,800, and 15,300 calendar yr BP. These major readvances should have been separated by intervals of general recession, some of which might have been punctuated by short-lived advances. Furthermore, the time scales of Holocene events and their Late-Wisconsin analogues should be comparable. Considering possible errors in C14 dating, this extended Holocene scheme agrees reasonably well with the chronology and magnitude of such Late-Wisconsin events as the Cochrane-Cockburn readvance (8000–8200 C14 yr BP), the Pre-Boreal interstadial, the Fennoscandian readvances during the Younger Dryas stadial (10,850-10,050 varve yr BP), the Alleröd interstadial (11,800-10,900 C14 yr BP), the Port Huron readvance (12,700–13,000 C14 yr BP), the Cary/Port Huron interstadial (centered about 13,300 C14 yr BP), and the Cary stadial (14,000–15,000 C14 yr BP). Moreover, comparison of presumed analogues such as the Little Ice Age and the Younger Dryas, or the Alleröd and the Roman Empire-Middle Ages warm interval, show marked similarities. These results suggest that a recurring pattern of minor climatic variations, with a dominant overprint of cold intervals peaking about each 2500 yr, was superimposed on long-term Holocene and Late-Wisconsin climatic trends. Should this pattern continue to repeat itself, the Little Ice Age will be succeeded within the next few centuries by a long interval of milder climates similar to those of the Roman Empire and Middle Ages.Short-term atmospheric C14 variations measured from tree rings correlate closely with Holocene glacier and tree-line fluctuations during the last 7000 yr. Such a correspondence, firstly, suggests that the record of short-term C14 variations may be an empirical indicator of paleoclimates and, secondly, points to a possible cause of Holocene climatic variations. The most prominent explanation of short-term C14 variations involves modulation of the galactic cosmic-ray flux by varying solar corpuscular activity. If this explanation proves valid and if the solar constant can be shown to vary with corpuscular output, it would suggest that Holocene glacier and climatic fluctuations, because of their close correlation with short-term C14 variations, were caused by varying solar activity. By extension, this would imply a similar cause for Late-Wisconsin climatic fluctuations such as the Alleröd and Younger Dryas. 相似文献
547.
Garnets in epidote-bearing gneisses and mica schists from the western Hohe Tauern, Austria, have been analyzed by optical, x-ray powder diffraction, wet chemical and electron microprobe methods.The garnets frequently show zonal structure and their core compositions are in the range 45–52% grossular, 31–44% almandine, 3–13% spessartine, 0–7% andradite and 0–2% pyrop. The refractive indices n=1.780–1.786 and the lattice parameter a=11.68–11.73 Å likewise are intermediate between almandine and grossular. It is suggested that there is complete solid solution between almandine and grossular, at least under the conditions of greenschist to low-temperature amphibolite facies of regional metamorphism of the Tauern area.
Prof. Dr. F. Karl starb am 15. 8.1972.
Dank. Die Mikrosonde wurde von der Stiftung Volkswagenwerk bereitgestellt, und die Probenahme wurde von der Deutschen Forschungsgemeinschaft unterstützt. Wir danken Herrn Dr. P. K. Hörmann (Kiel) für die naßchemische Granatanalyse und Herrn Dr. K. Abraham (Bochum) für die Bereitstellung seines Korrekturprogrammes für Mikrosondenanalysen. 相似文献
Prof. Dr. F. Karl starb am 15. 8.1972.
Dank. Die Mikrosonde wurde von der Stiftung Volkswagenwerk bereitgestellt, und die Probenahme wurde von der Deutschen Forschungsgemeinschaft unterstützt. Wir danken Herrn Dr. P. K. Hörmann (Kiel) für die naßchemische Granatanalyse und Herrn Dr. K. Abraham (Bochum) für die Bereitstellung seines Korrekturprogrammes für Mikrosondenanalysen. 相似文献
548.
Karl -Heinz Nitsch 《Contributions to Mineralogy and Petrology》1972,34(2):116-134
At pressures which are expected in the earth's crust, the high temperature border of the lawsonite stability field is marked by reaction lawsonite = zoisite + kyanite/andalusite + pyrophyllite + H2O. (1a) The equilibrium data of reaction (1a) have been experimentally determined, and the equilibrium curve is characterized by the following P, T-data: 4 kb; 360±20° C; 5 kb; 375 ±20° C; 7kb;410±20° C. In the P, T diagram the equilibrium curve of reaction lawsonite + quartz = zoisite + pyrophyllite + H2O (6) is very close to the curve of reaction (1a); the distance is smaller than the error stated for curve (1a), i.e. below ±20° C. The stability fields of lawsonite and anorthite + H2O are not adjacent fields in the P, T diagram. This means that no stable reaction of lawsonite to anorthite + H2O can exist. Thus, the CaAl-silicate formed by the decomposition of lawsonite is always zoisite. Further, as shown by experimental determination of reaction calcite + pyrophyllite + H2O = lawsonite + quartz + CO2, (7) lawsonite can coexist with a gas phase only if the CO2 content of the gas phase does not exceed 3±2 Mol-%. This means, for metamorphism of lawsonite glaucophane rocks, that the fluid phase that was present during metamorphism has been quite rich in H2O. Ernst (1971, in press) who applied a different, indirect investigation method when studying the composition of the fluid-attending Franciscan and Sanbagawa metamorphism has come to the result that during metamorphism of lawsonite-glaucophane rocks the fluid phase did not contain more than 1–3 Mol-% of CO2. 相似文献
549.
550.
The thicknesses of slag piles at a smelling site in Midvale. Utah, were determined using geophysical methods; this information was needed to estimate the cost of removing or isolating slag that has the potential to contaminate ground water. From a small-scale preliminary investigation that, included terrain-conductivity profiling, low-frequency resistivity measurements, and induction logging, the electrical resistivities of the slag and the underlying sediment were determined to be approximately 100 Ω-m and 15 Ω-m, respectively. Because electromagnetic measurements are affected by such significant contrasts, terrain-conductivity profiling and time-domain electromagnetic soundings were used to determine the thicknesses of the slag piles. Generally, the estimated thicknesses from both methods were consistent and geologically plausible. In some instances, reliable estimates of the thicknesses could not be obtained because, for example, the measurements were affected by buried metal objects.
In this case study, we emphasize three principles that might help investigators at other smelter sites. First, a small-scale preliminary investigation saves time and money because those geophysical methods that have the greatest likelihood of success can be determined. Second, when the results from several geophysical methods are consistent, the confidence in the interpretation increases. Third, geophysical characterization is not always successful. Nonetheless, because of its outstanding advantages, it should be used before other more expensive characterization methods arc tried. 相似文献
In this case study, we emphasize three principles that might help investigators at other smelter sites. First, a small-scale preliminary investigation saves time and money because those geophysical methods that have the greatest likelihood of success can be determined. Second, when the results from several geophysical methods are consistent, the confidence in the interpretation increases. Third, geophysical characterization is not always successful. Nonetheless, because of its outstanding advantages, it should be used before other more expensive characterization methods arc tried. 相似文献