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1.
B. Lammerer I. Fruth D. D. Klemm E. Prosser K. Weber-Diefenbach 《International Journal of Earth Sciences》1976,65(1):436-459
Geologic, petrological and geochemical investigations have been carried out in the western part of the “Zillertaler Alpen”. Important results are:
- The premetamorphic material of the Greiner series consists of conglomerates, breccias, arcosic-sandstones or greywackes, bituminous shales, volcanic lavas and tuffs.
- The southern part of the “Zentralgneis” shows a differentiation trend from alkaline granite to quarzdiorite with predomination of granodiorite.
- Chemical relationships of granodiorite to its restitic inclusions allow the supposition of a palingenetic origin of the granitic rocks.
- At least two stages of metamorphism can be differentiated.
- Parts of the Greiner series, covered by triassic metasediments, are supposed to be of Permian age. A lower age boundary can not yet be given.
- Some vertical, northeast striking faults with throws of more than 1 or 2 kilometers produced southward verging drag folds.
- Geodynamic aspects, revealed from regional metamorphism and tectonics, are discussed.
2.
Dr. Elmar Sabelberg 《GeoJournal》1986,13(1):59-66
The “South-Italian city” is characterized at four different levels as an independent cultural-genetic city-type:
- The characteristics arrangement of the functional areas and the residential areas of different social groups is represented in a model.
- From the model, developments and changes in the arrangement of the functional areas can be identified which clearly deviate from those which are derived from the universal city model.
- Some of the structural individuality can be directly explained by the peculiar features of the respective social and economic history.
- Some of the special features must, however, be traced back to a wider historico-cultural background. Through this run processes which flow through the universal city development in similar forms, to the deviating structure of the “South-Italian city”.
3.
Based on research on the “Xinyu-type” Sinian iron deposits in Jiangxi Province and metamorphosed iron deposits in Jiangkou and Qidong of Hunan, Sanjiang and Yingyangguan of Guangxi, Longchuan of Guangdong and some other areas in Fujian, the authors have come to the following conclusions:
- The metamorphosed late Precambrian iron ores widespread in south China may be roughly assigned to two ore belts, namely the Yiyang-Xinyu (Jiangxi)-Jiangkou(Hunan)-Sanjiang (Guangxi) ore belt or simply the north ore belt, and the Songzheng(Fujian)-Shicheng (Jiangxi)-Bailing (Longchuan of Guangdong)-Yingyangguan (Guangxi) ore belt or the south ore belt. Tectonically, the former lies along the southern margin of the “Jangnan Old Land”, while the latter along the northwestern border of the “Cathaysian Old Land”.
- Iron deposits of this type occur exclusively in the same interglacial horizon of the Sinian Glaciation in south China. Above and below the ore bed there lie the glacial till-bearing volcanic-sedimentary layers.
- Based on sedimentary features, the iron formations can be divided into four types: silica-iron-basalt formation, silica-iron-clastic rock formation, silica-iron-tuff formation and silica-iron-carbonate rock formation, which progressively grade into each other.
- Iron ores were formed at the late stage of late Proterozoic rifting in neritic environments, with their distribution governed by the rift valleys on the margins of the “Jiangnan Old Land” and “Cathaysian Old Land”. Consequently, intense mafic volcanism as well as weathering and denudation of palaeocontinent during rifting provided material sources for the formation of iron deposits. Meanwhile, warm and humid stationary neritic environment during the south China great glacial period constitutes favorable palaeoclimatologic and palaeogeographic conditions for the deposition of iron ores.
- The iron formations have undergone regional metamorphism of greenschist-amphibolite facies.
4.
Kuno Priesnitz 《International Journal of Earth Sciences》1968,58(2):427-438
The study deals with the comparison of corrosion forms in differently soluble rocks from different climatic regions, namely forms of the naked karst (lapies), depressions, and corrosive plains. The far-reaching morphographic conformity of corresponding forms permits some general conclusions:
- The forms in question have the same genesis, there is no casual convergence of forms. It would be convenient to term them as forms of the salt-, gypsum-, and carbonate karst. There is no justification for a fundamental distinction between the “karstification” of limestone and the “leaching” of gypsum and salt.
- The different liability to karstification (Karstgunst) of rocks can be compensated by a different liability to karstification due to climatic factors.
- Similarly the other factors of karstification vary gradually; they add up or compensate each other. A classification of climatic-morphological karst provinces seems to be possible only by means of analysis and balance of the single factors and their effects.
5.
H. Kenneweg 《GeoJournal》1994,32(1):47-53
The development of inventory activities in the field of forest damage assessment and monitoring during the last decade in Germany and the present state are recorded as far as remote sensing has been involved. Any forest inventory is influenced by external factors, and the resulting difficulties for an introduction of new technologies are described. The following tasks and/or methods are discussed: -global approaches to deforestation monitoring -working experience from local and regional case studies -vegetation and vegetation-damage monitoring in ”urban forestry” -sampling approaches for large areas -the contribution of spectral signatures and satellite remote sensing to damage assessment 相似文献
6.
Dr. Ulrich von Rad 《International Journal of Earth Sciences》1970,60(1):331-354
Paleocurrent directions can be reconstructed by determining optically the preferred orientation of longest grain axes of sediments; this can be estimated by measuring the anisotropy of magnetic susceptibility (Rees, 1965). In order to check the applicability of both methods, the orientation of large- and small-scale sedimentary structures (cross-bedding, sole markings, grain orientation) was compared with the “magnetic fabric” of some sand and silt layers of different ages and origins:
- Rosario Formation (Late Cretaceous), La Jolla: thin siltstone layers with small-scale current-ripple cross-lamination;
- Monterey and Topanga Formations (Miocene, Los Angeles Basin): graded and laminated sandstone beds (“turbidites”);
- Holocene submarine La Jolla Fan: graded and cross-laminated sand layers (Rees, v.Rad &Shepard, 1968).
7.
Pasquale Iannello 《International Journal of Earth Sciences》1971,60(2):630-655
The detailed investigation of the Bushveld granites, around the Rooiberg area, has revealed the existence, in the field, of at least three main types:
- Granophyric rocks, which form a belt (transition-zone) between the country rocks (sediments and felsite) and the Main granite.
- Main granite, which is the most common type of granite.
- Younger granites, which are responsible for the tin mineralization.
8.
Dr. Heinz -Peter Jons 《International Journal of Earth Sciences》1986,75(2):461-493
The analysis of the martian relief leads to the conclusion that some of the most important relief elements are either concentrically or radially arranged with respect to a central structure and hence form aureoles. In this paper four different types of aureoles are identified and described:
- impact aureoles (as result of extradynamics),
- volcanic aureoeles (as result of lava flow through vents),
- tectonic aureoles (as result of isostatic adjustment and/or settlement),
- permafrost-related aureoles and mega-aureoles (as result of migration above thawing permafrost in areas with high relief).
9.
Dr. Christoph Hoffmann 《International Journal of Earth Sciences》1976,65(1):939-966
In the central area of the early paleozoic Damara belt migmatites and some types of granites (sensu lato) crop out. Conventional petrographic data were collected and melting experiments were carried out with 63 samples of such rocks. Based on these data, migmatite genesis can be classified as follows:
- Formation by partial melting and separation of more liquid and more crystalline fractions, the melting behaviour of these fractions has to be principally similar then.
- Formation by injection of “geologically liquid” crystal-melt mixes into rocks of (incidentally) similar or (more frequently) dissimilar melting behaviour.
- Formation by partial melting of metasediments of originally different composition. The method is applied and demonstrated for outcrops with complicated interrelations and it is shown that temperature estimates are possible thereby (670° to 710° at 4–5 kb H2O pressure in the central Damara belt).
10.
Mn-activated cathodoluminescence can be used in several fields of carbonate petrography. It may, for instance, be possible to recognize
- cement sequences and their correlation (Tab. 1, Figs. 1, 2, 4; Tab. 2, Fig. 1)
- growth fabrics of skeletons (Tab. 2, Figs. 2, 3, 4; Tab. 3, Figs. 1, 2)
- dolomitisation processes and problems (Tab. 1, Figs. 1, 2; Tab. 4, Fig. 2)
- transformation paths from Mg-calcite to calcite and from aragonite to calcite (Tab. 2, Fig. 1; Tab. 3, Figs. 3, 4; Tab. 4, Fig. 1)
- growth structures in certain types of ooids (Tab. 1, Fig. 4; Tab. 3, Fig. 3; Tab. 4, Fig. 1)
- reworked skeletal particles (Tab. 3, Fig. 4)
- phantom grains and fossil-outlines in a micro- or macrocrystalline groundmass (Tab. 4, Figs. 2, 3)
- healed fissures crossing micro- or macrocrystalline carbonate rocks (Tab. 4, Fig. 4).
11.
Dr. Barbara Theilen-Willige 《International Journal of Earth Sciences》1982,71(1):318-327
The following facts have supported the origin of the Araguainha circular structure in Central Brazil by a meteoritic impact:
- the almost circular contour
- the impact-morphologic sequence including a central uplift, ring walls and a basin rim of escarpments
- outcrops of suevites and mixed breccias
- the evidence of shock metamorphism
- the presence of shatter cones, and
- negative anomalies of the total intensity of the magnetic field at the center of the ring structure.
12.
Alexander A. Godovikov George C. Kennedy 《Contributions to Mineralogy and Petrology》1968,19(2):169-176
Prior experimental work has shown that in the laboratory the mineralogy of eclogites is sensitive to the ratio of CaO ∶ MgO ∶ FeO and that the reaction pyroxene + kyanite?garnet + quartz proceeds to the right at high pressures in rocks rich in magnesium and to the left in rocks rich in calcium and iron. Typical basalts crystallized at high pressure never contain kyanite. The chemistry and mineralogy of a large number of naturally occurring eclogites show they belong to three classes.
- Kyanite-free magmatic eclogites, rich in magnesium, from:
- kimberlites
- dunites and serpentinites.
- Kyanite-bearing eclogites and grosspydites rich in CaO and low in FeO with intermediate MgO from:
- kimberlites
- gneisses.
- Kyanite-free eclogites of metamorphic origin rich in iron with low magnesium and intermediate amounts of calcium from:
- glaucophane schists
- gneisses.
13.
W. E. G. Taylor 《International Journal of Earth Sciences》1968,58(2):564-587
The paper presents novel information on the Caledonian orogeny in Ireland. A series of Dalradian (Upper Precambrian-Lower Cambrian) metasedimentary rocks occur as an envelope to a granitic igneous complex at Slieve Gamph, Western Ireland. These metasedimentary rocks have been deformed at several distinct times and evidence is shown for the following sequence of events:
- formation of major nappe structures and a tectonic slide. The axial-plane traces of the folds probably trended N. E.-S. W.
- formation of upright, gently plunging folds with axial-plane traces of the folds trending N. E.-S. W. Emplacement of the components of the Slieve Gamph igneous complex.
- formation of a conjugate set of folds:
- Open folds with N. N. E.-S. S. W. trending axial-planes which dip to the east,
- Open folds with E.W. trending axial-planes which dip to the north.
- formation of kink-bands, open and conjugate folds with an axialplane trace trending N. W.-S. E.
14.
Prof. Dr. Helmut G. F. Winkler 《International Journal of Earth Sciences》1976,65(1):874-885
The author's concept (1970, 1974) of evaluating metamorphic conditions is explained on the basis of most recent petrologic data. The major points treated are:
- Instead of usual petrographic mapping, petrographic work in the field is aimed at specific “targets”, i.e., rock compositions. This is so because only specific rocks may give petrogenetically relevant information in the four metamorphic grades.
- There are very many mineral reactions in metamorphism but only a few are petrogenetically significant. These are important to know, and they are graphically demonstrated. Any mineral assemblage that is formed by a significant mineral reaction must be verified as a paragenesis of mutually contacting minerals. Only such parageneses deserve to be mapped in the field as isograds or isoreactiongrads.
- Crossing isograds or isoreactionsgrads provide data on temperature and pressure during metamorphism for that part of a metamorphic terrane where the crossing has been observed.
- The sequence of isograds or isoreaction-grads may be a pressure indicator. Moreover, such a sequence provides geodynamic information whether a larger metamorphic area has been lifted up evenly or has been tilted while it was uplifted after metamorphism.
15.
Diplom-Geologe Dr. Werner Fiebiger 《International Journal of Earth Sciences》1975,64(1):641-652
Marine sedimentary iron ore samples from various early and middle Precambrian ore provinces of the world (“itabirite, banded ironstones, jaspelites, Quarzbändererze”) have been investigated by means of vaporisation pyrolysis gaschromatography (VPGS) with regard of their contents of organic substances. The main results were:
- All investigated itabirite samples show, concerning their qualitative hydrocarbon content, a typical distribution in chromatographic diagrams.
- The amount of pristane and phytane as results of the decomposition of chlorophyll points at a reasonable photosynthetic activity of organisms during the itabirite genesis.
16.
Concordant granite sheets from the granulite facies Scourian Complex, N.W. Scotland exhibit the following features:
- a common planar fabric with their host pyroxene granulites;
- the presence of an exsolved ternary feldspar phase;
- a low-pressure, water-saturated minimum composition;
- K/Rb ratios (450–1,350) distinctly higher than most upper crustal granites but similar to the surrounding granulites;
- low absolute concentrations of the rare earth elements (REEs), light REE enrichment, and large positive Eu anomalies.
17.
Massive sulfide deposits located on Hercynian islets of northwestern Morocco exhibit four main characteristics: They are strata-bound massive pyrrhotite deposits mined for sulfur and/or base metals occasionally occurring as sulfides of workable grade. Volcanic rocks with which these massive sulfide orebodies are associated are scarce, although always present as acid flows of submarine emissions of either rhyolitic or more often quartz-keratophyric nature. Later on, basic plutonics intruded the pelitic country rocks. Stockworks underlying the massive sulfide orebodies are common, but not systematic. When present, they occur in siltite ± phyllite ± carbonate rocks at the wall of massive sulfide lenses. They consist of fissural disseminations transformed by epimetamorphic recrystallization and by one schistosity generally concordant with s0. Associated alterites and exhalites belong to three types, i.e., sericitite (or biotite-rich rock), chloritite, and/or chert (jasper). Generally well located in a back-arc basin environment characterized by a two-phase geological history, i.e., “extension and volcanism, compression and metamorphism”, these volcano-sedimentary deposits exhibit distal features with regard to the volcanism coeval with their sedimentation. They are mostly linked with strongly reducing environmental properties entailing pyrrhotite and/or magnetite syngenetic deposition, whatever the iron activity. 相似文献
18.
Franz Zwittkovits 《International Journal of Earth Sciences》1968,58(2):378-395
Clints are corrasional features with rock inclined to develop karstic forms which originated by the directed run-off of flowing water. The most typical and far spread features occur in the Northern Calcareous Alps where they are marked by their optimum distribution within the former glaciated areas. With few exceptions, the clints occurring in the Alps are recent. Their age can be established as Late- to Post-Glacial. On the whole the karstic features extend from the highest summits deep down into the valleys but a zone of most extensive distribution occurs between 1900–2000 m and 1200–1300 m. The upper limit is controlled by mechanical weathering, the lower limit by the variation of the conditions of run-off below the soil and vegetation cover. As to ecology the total clint zone can be divided into two areas:
- The zone of free development of the karst (sharp edged features) and
- The zone of subcutaneous karst development (rounded features).
19.
20.
Prof. Dr. G. Haase Dr. L. Händel Dr. Chr. Nagel Dr. Chr. Opp Dr. R. Zierath 《GeoJournal》1990,22(2):153-165
Problems of landscape and resource protection resulting from the intensification of land-use can be mastered only by intersectoral planning and a land management considering (landscape-)ecological principles right from the beginning. In the district of Leipzig ecological studies in the '80ies have focussed on:
- Determination of the regional pattern of atmospheric immissions;
- Registration of heavy metals in soil and vegetation;
- Soil compaction, soil erosion;
- Study of stress indicators in the aeration zone and in the top-most aquifer in order to examine barrier effects in the percolation process.