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In the Northwest German Basin of Central Europe, Late Triassic interaction of normal faulting and salt diapirism during regional extension in subsalt basement locally initiated lateral flow of surface-piercing salt in namakiers (salt glaciers). Using seismic sections and variance attribute maps derived from high-resolution three-dimensional seismic data, we show that when a syndepositional fault cuts a near-emergent diapir crest, the caprock carapace was breached, opening a pathway for salt extrusion. The fault escarpment and the adjacent fault-induced depression allowed focused gravity-driven downward flow of salt across the land surface (a namakier) and its subsequent preservation and encasement in continental (arid redbed) sediments. Geodynamically there is an apparent distinction between the compressional setting of modern namakiers in the arid deserts of Iran and the fault-intersected extensional setting of stacked Keuper namakiers. Stacked namakiers preserved in thicknesses that are seismically resolvable are interpreted to indicate hyperarid conditions in Keuper time. The climate was typical of the highly continental Late Triassic Pangaean supercontinent as it rifted and sagged to form the incipient Atlantic Ocean. Keywords: salt glacier, diapirs, Northwest German Basin, continental redbeds, extension. doi: 10.1130/G23378A.1

Loehe is brought home to his church Wilhelm Loehe died January 2, 1872. Within a decade of his death, in 1881, this statement was inserted into the third edition of [...]

A RELIGIOUS SONDERWEG? REFLECTIONS ON THE SACRED AND THE SECULAR IN THE HISTORIOGRAPHY OF MODERN GERMANY If one had to identify the moment at which religion officially 'arrived' in the [...]

Walter Benjamin, perhaps the most prolific promoter of material cultural memory in German letters, wrote in 1932 that memory was 'not the instrument for exploring the past, but rather a [...]

About 1000 zircon grains from a diamondiferous quartzofeldspathic rock of the Saxonian Erzgebirge were investigated for inclusions using optical microscopy and confocal laser-Raman spectroscopy. Cathodoluminescence imagery was applied to characterize the growth zone of zircon where the inclusions occurred. The most abundant inclusion minerals are microdiamonds. Coesite was not detected. However, garnet and jadeite occur as rare inclusions in zircon cores where diamonds are lacking. Jadeite was detected for the first time in quartzofeldspathic rocks from the crystalline complex of the Erzgebirge. The compositions of the pristine garnets in the zircons are similar to those of core areas of millimeter-sized garnets but the original garnet composition of the early metamorphic stage is only preserved in zircon. Intracrystalline diffusion at temperatures as high as 1000 [degrees]C resulted, for instance, in higher Ti concentrations in garnet cores compared with garnet enclosed in zircon. Rutile, quartz, and the compositions of jadeite and garnet inclusions in zircon and of phengite inclusions in cores of large garnets were applied for geothermobarometry. The results, related to an early metamorphic stage, are 650[degrees]C and 18 kbar, which represent conditions at the base of a thickened continental crust before deeper subduction.

An integral method of data evaluation for chemical dating of accessory uraninite by electron microprobe analysis and electron microscopy is proposed. The internal structure of uraninite grains, the contents of Si, Ca, and Fe, and tests for loss or gain of Pb and U are suitable criteria to decide whether or not a given crystal area was affected by secondary alteration. The method was applied to uraninite from the Kirchberg granite, Erzgebirge, Germany, and an age of 330 [+ or -] 5 Ma ([+ or -] 2 [sigma]) was constrained. This result supports earlier assumptions that there were at least two events of Hercynian granite magmatism separated by a time gap of about 40 Ma, and that the magmatic evolution of the Kirchberg granite is not related to the formation of the W mineralisation developed in the endocontact of this granite. Secondary alteration of uraninite is probably closely related to the formation of U deposits in the vicinity of the Kirchberg massif which was extensively mined in the past.

A new genus Ibergirhynchia, a member of the rhynchonellide superfamily Dimerelloidea, is described for the species Terebratula contraria Roemer, 1850, from Early Carboniferous deposits of the Harz Mountains, Germany. Ibergirhynchia contraria is from a monospecific brachiopod limestone that formed on top of the drowned Devonian Iberg Reef which persisted as a seamount during Famennian and Early Carboniferous times. Ibergirhynchia contraria is considered a cold seep-related brachiopod based on this locality. Such seep associations have been observed for Mesozoic representatives of the rhynchonellide superfamily Dimerelloidea. Ibergirhynchia is considered the first Paleozoic representative of the family Rhynchonellinidae. Ibergirhynchia resembles Dzieduszyckia externally and may be derived from this dimerelloid.

Vein-type and bedding-concordant mesothermal (180-410[degrees]C) stibnite sulphosalt mineralization at Arnsberg, NE Rhenish Massif, Germany, is hosted by Carboniferous pyrite-rich black shales and siliceous limestones. A detailed sulphur isotope study of the stibnite-sulphosalt mineralization and pyrite from a variety of regional host-rock lithologies has been carried out using an in situ laser combustion technique. The [[delta].sup.34]S values of stibnite of various textural types are distinctly negative and lie in a narrow range between -23.9 [per thousand] and -17.1 [per thousand] (mean -20.1 [per thousand]). In contrast, regional sedimentary-diagenetic pyrites display a large variation of their [[delta].sup.34]S values between -45.4 [per thousand] and +9.3 [per thousand]. There is little evidence for significant modification of the hydrothermal fluid during deposition and the S isotope signatures suggest that the sulphur of the stibnite mineralization was not locally derived. The [[delta].sup.34]S values of pyrite in Givetian shales display a significantly narrower range of-28.2 [per thousand] to -7.5 [per thousand] and their mean composition (-17.1 [per thousand]) is close to the [[delta].sup.34]S values of the Arnsberg stibnite deposits. Considering the temperature-dependent isotopic fractionation between stibnite and reduced sulfur species, the [[delta].sup.34]S values of the mineralizing fluid (-16.8 [per thousand]; 200[degrees]C) and the Givetian rock source are essentially identical. Therefore, we propose a model of leaching and isotopic homogenization of sulphur from the Middle Devonian shales and a subsequent northward migration of these fluids. The fluids were trapped in permeability-controlled positions within anticlinal zones, where fluid cooling induced deposition of stibnite and sulphosalts. Keywords: antimony deposits, black shales, sulphur, isotopes, fluid flow.

Thin, but laterally widespread, fallout ash tuff layers interbedded with complex fluvio-lacustrine successions of the Carboniferous-Permian late Variscan intermontane Saar-Nahe Basin in southwestern Germany provide important tephrostratigraphic markers in the purely continental depositional setting. The tuffs are rhyolitic to rhyodacitic and indicate geochemical affinities to Moldanubian Variscan S-type granitoids. The volcanic ashes are suggested to have been derived from the general region of the central and northern Black Forest (southwestern Germany) and the northern Vosges (eastern France) at 100-150 km distance south of the Saar-Nahe Basin. Six tuff beds from the Jeckenbach and Odernheim subformations (Meisenheim Formation, Glan Group) have been correlated within the basin over a distance of 50 km by mapping and whole-rock geochemical fingerprinting. In each subformation, three tuffs can be well distinguished using geochemical discriminant function analysis. Additional comparisons of trace and rare-earth element contents provide further criteria for the differentiation of individual tuff beds. These discriminations show that the tuffs have unique chemical fingerprints, probably reflecting differences in the original composition of the parent volcanic tephra. Thus, chemical differences between the tephrostratigraphic markers are geologically significant and provide a powerful tool for establishing tuff layer identification and correlation within the complex sedimentary sequence of the Saar-Nahe Basin. They also provide clues to the tectonomagmatic settings of the source volcanoes. Keywords: tuff, pyroclastics, Permian, Saar-Nahe Basin, geochemistry, geochemical indicators.

The effects of mantle metasomatism on the sulfide phase in mantle xenoliths in general, and on the Os isotopic system in particular, have received increased attention in recent years. Here, we report on Os isotopic systematics of metasomatized mantle xenoliths from the late Quaternary Eifel (Dreiser Weiher and Meerfelder Maar) and neighboring Vogelsberg volcanic fields, which provide insight into the effects of melt extraction and metasomatism on Os isotopes and place constraints on the evolution of the lithospheric mantle component beneath central Europe. Sixteen harzburgite, lherzolite, and pyroxenite xenoliths from the Eifel and two lherzolite xenoliths from the Vogelsberg were analyzed for Os isotopes. Samples from the anhydrous peridotite suite (Ib) are highly variable in their Os isotopes, ranging from subchondritic values ([sup.187]Os/[sup.188]Os = 0.1236) to suprachondritic values ([sup.187]Os/[sup.188]Os = 0.1420), indicating that some of these samples have been overprinted by the addition of radiogenic Os and have lost the primary mantle Os that was presumably present. The suprachondritic values suggest a source for this Os in a reservoir with a time-integrated Re/Os ratio greater than that of the bulk Earth. Eifel samples with Os contents > 1.5 ng/g from the hydrous suite (Ia) have relatively unradiogenic Os isotope compositions ([sup.187]Os/[sup.188]Os = 0.1208-0.1237) and [Al.sub.2][O.sub.3]-Os isotopic systematics consistent with ancient melt depletion and isolation from the convecting asthenospheric mantle for time periods similar to the age of the overlying crust (~1.5 Ga) as well with results from peridotite massifs in the European region. The LREE-metasomatism and the enrichment of Os (up to 6.47 ng/g) and As (sulfide metasomatism?) in the hydrous suite is strongly inversely correlated with the Os isotope ratios, demonstrating that mantle processes such as metasomatism can significantly modify the Os isotope chemistry of mantle xenoliths.

Early Carboniferous (latest Visean) seep deposits occur on top of the drowned Middle Devonian-Late Devonian Iberg atoll reef, Harz Mountains, Germany. These deposits include limestone with a low-diversity but high-abundance fauna of rhynchonellid brachiopods and rare solemyid bivalves, as well as microbial limestone. Rhynchonellids form dense, autochthonous shell accumulations and are generally articulated. They are closely associated with hydrocarbon-derived carbonates. The carbonates exhibit [[delta].sup.13]C values as low as -32 [per thousand], relative to the Peedee belemnite standard, revealing that they are predominantly hydrocarbon derived. The fauna, carbonate fabrics, and isotope signatures provide unequivocal evidence for a seep origin of the Visean deposit. The occurrence of solemyid bivalves supports this interpretation as members of this family (1) are well known for their relationship with chemoautotrophic bacteria and (2) have been reported from ancient and modern seeps. Possible hydrocarbon sources are thermogenic methane derived from the volcanic base of the Iberg reef or methane from a petroleum reservoir. Keywords: seeps, hydrocarbons, carbonates, chemosynthesis, stable isotopes, Carboniferous.

Tiny hoopoe-like birds of the extinct family Messelirrisoridae are among the predominant small perching birds in the Middle Eocene (ca. 49 million years ago) avifauna of Messel (Hessen, Germany). Members of the Messelirrisoridae are the earliest-known representatives of the hoopoe/wood-hoopoe lineage and are sister taxa of recent Upupidae (hoopoes) and Phoeniculidae (wood-hoopoes). Outgroup comparison with the Messelirrisoridae facilitates character-state analysis within the Phoeniculidae and Upupidae. In this study, I describe a new species, Messelirrisor grandis, which is the largest species of the Messelirrisoridae known so far.

We used the technique of expanded General Circulation Model (GCM) downscaling to derive time series of daily weather for the analysis of potential climatic change impact on a river catchment in Northern Germany. The derived time series was then fed into a spatially distributed hydrological model to simulate various water balance components and river discharge. All components of this modelling approach are known to provide fairly accurate results under normal (current) climatic conditions. Hydrological time series, their statistics and spatial patterns of various water balance components, resulting from a 'business-as-usual' emission scenario, were analysed. The simulation results showed that if everything apart from climate is held constant, a significant increase in river discharge may be expected in the coming decades as a consequence of increased rainfall amounts. Although the modelling approach provides an operational way of performing watershed climate change impact studies, many uncertainties still have to be considered.

The third- and fourth-order sequential arrangement of continental sedimentary strata in the Permo-Carboniferous Saar-Nahe Basin preserves a detailed record of contemporaneous faulting and volcanism. Transgressive lacustrine facies of the Upper Carboniferous coincide with the stratigraphic position of extrabasinally derived pyroclastic fallout layers and features of synsedimentary tectonism such as unconformities, thickness and facies changes across faults, and seismogenic deformation structures. The tectonic imprint on fourth-order cycle initiation is further documented by abrupt vertical facies transitions during lake transgression, implying rapid and episodic rather than gradual basin subsidence. This interaction becomes much more pronounced within the fluvially dominated Lower Permian, when tectonism controlled both the ascent of large volumes of magma within the basin as well as episodic enlargement of accommodation space and depositional area. Major extrusive volcanic units are preferentially associated with sequences recording transgression that are only preserved in fault-bounded hanging wall traps starved from clastic sediment input. It is suggested that the stratigraphic position of pyroclastic fallout within the sequential framework of basins elsewhere, provides an important analytical tool for the identification of contemporaneous tectonic events and as such form a discriminant between purely climatically induced Milankovitch band cycles versus those involving a tectonic control. Keywords: Carboniferous, Permian, stratigraphy, Saar-Nahe Basin, strike-slip faults.

An integrated reflection and refraction seismic survey across the Permian-Cenozoic Northeast German basin yields new insights on the evolution of intracontinental basins. No precursor rift basin was observed, but there is evidence of lower. crustal thinning and an initial magmatic stage. Minor Triassic rifting and Late Cretaceous compressional tectonics indicate that intraplate deformation was strongly influenced by older structures. Intraplate thinning and contraction were strongly decoupled vertically and accommodated at distances longer than profile length ([approximately]500 km). Thermal destabilization of a stressed, inhomogeneous lithosphere, rather than plate-boundary forces, controlled the evolution of the Northeast German basin.

A study was conducted to determine the time of formation and the metamorphism of quartz-feldspar rocks of the Gnesis-Eclogite Unit (GEU) of the Variscan Erzgebirge, Germany. Results showed that after high pressure/high temperature equilibration, the GEU experienced strong near-isothermal decompression at high temperatures, extensive re-equilibration at medium pressures and fast cooling during continued uplift. Moreover, the tectono-evolution and protolith formation occurred between 470 and 524 Ma.

The clinopyroxenes of the xenoliths from the subcontinental lithospheric mantle under the Eifel in Germany were examined for trace element and Nd-Sr isotope compositions to document intra-suite variations and to constrain the processes involved in the formation of heterogeneities. Results showed that melts parental to the Dreiser Weiher pyroxenites are genetically related to the young alkali basaltic volcanics and these melts can be derived from distinct domains of the mantle.

The epidermal anatomy of Barthelopteris germarii, a late Paleozoic seed fern, is described on the basis of material from the Upper Stephanian of Central France. A number of features are described for the first time for this species. Some have never been reported for late Paleozoic pteridosperms. Although our material is in most respects very similar to previously described material of B. germarii from Germany, there are also some striking differences, especially the peltate glandular trichomes that are very common in the French but completely absent in the German material. Their presence is most probably an ecological adaptation as in many modern plants. This and other epidermal and gross-morphological features (e.g., the presence of papillae on subsidiary cells of the stomata, anastomosing venation) indicate that B. germarii was well adapted to stressed conditions. Of more general interest is the preservation of the material. There appears to exist a clear relationship between the preservation of anticlinal walls and the thickness of the parenchymatic mesophyll; anticlinal walls are very well preserved where parenchyma was thin. Therefore, the absence of anticlinal walls in fossil cuticles, which has often been used as a taxonomic character, is not necessarily a primary feature. Key words: Barthelopteris germarii; Carboniferous; cuticular analysis; ecology; preservation; Pteridosperms; trichomes.

Peraluminous granites of the Erzgebirge-Fichtelgebirge, Germany, are hosts of various members of the monazite group of minerals that display an unprecedented compositional diversity. The Eibenstock S-type granite constitutes the third reported occurrence worldwide of brabantite and the first occurrence of this mineral in a granite. Many new occurrences of cheralite-(Ce), as well as a monazite-group mineral intermediate between monazite-(Ce) and huttonite for which the term huttonitic monazite is proposed, were discovered. Even 'common' monazite-(Ce) may show extreme ranges of actinide and lanthanide element concentrations. The granites that host brabantite and cheralite-(Ce) are highly differentiated, strongly peraluminous, low-temperature residual melts of S-type affinity, which are rich in fluorine and other volatile constituents but depleted in thorium and the light rare-earth elements. Such highly evolved, volatile-rich compositions resemble rare-element pegmatites and appear favorable for the precipitation of cheralite-(Ce) and brabantite, but not of monazite with large amounts of huttonitic substitution. Instead, these minerals occur preferentially in F-poor biotite and F-rich Li-mica granites of A-type affinity. Irrespective of the level of uranium in silicate melts, which may exceed that of thorium, the substitution of uranium in monazite remains limited. The compositional data reported here are consistent with complete miscibility in the monazite-(Ce)-brabantite solid solution series under magmatic conditions. These granites contain monazites that span almost the entire compositional range reported for monazite-group minerals worldwide, and therefore granites appear to be ideal rocks in which to study the crystal chemistry of this mineral group in general.

A kinematic/geometric model for the late- to post-Variscan period at the western border of the Bohemian massif was discussed. The faults and mineralized tension gashes studied revealed the deformation stages, namely, Upper Carboniferous subvertical tension gashes, Upper Carboniferous reverse faults, Cretaceous subhorizontal tension gashes and reverse faults and Neogene normal faults. The Franconian Lineament was also found to play an important role in the lithosphere's strength and in the interplate compression strain localization.

The Caledonian deformation of the Brabant Massif and the Rugen Early Palaeozoic has been compared by structural analysis including strain determinations, X-ray texture analysis, illite crystallinity and vitrinite reflectivity. Both areas have experienced weak internal deformation under anchimetamorphic to very low-grade metamorphic conditions. The deformation of the Brabant Massif is characterized by (a) a pronounced diagenetic foliation which resulted from compaction and weak extensional tectonics; (b) tilting or weak folding of the Cambrian strata around the Cambrian/Ordovician boundary without internal deformation; (c) a main phase of Caledonian deformation in the Lower Devonian which was associated with open folding and an axial-plane pressure solution cleavage; (d) bending of Caledonian structures from northwest-southeast to northeast-southwest. The internal deformation appears homogeneous with decreasing strain values towards upper structural levels. The strain ellipsoid is predominantly prolate with the main axis of extension parallel to the bedding-cleavage intersection lineation. It is interpreted as the result of superposition of compaction, tectonic shortening and volume loss through pressure solution. The Rugen Early Palaeozoic is less deformed and less metamorphosed under anchizonal conditions. While the upper structural level is almost undeformed, towards the deeper structural levels a spaced and then a continuous slaty cleavage is developed which is successively crenulated by a fracture cleavage. The internal deformation appears inhomogeneous due to several thrust zones with somewhat higher strain values. Outside the thrust zones strain values increase towards lower structural levels, but not significantly. The strain ellipsoid is prolate with a strongly varying orientation of the X-axis. The structural inventory of both areas is comparable with other fold-and-thrust belts. While the Rugen Palaeozoic represents an imbricated thrust-fan of an upper structural level with discrete thrusts and inhomogeneous strain, the Brabant Massif represents a deeper structural level dominated by folding and more homogeneous internal deformation.

The mechanisms of silica transport across the membranes of Halichondria panicea were analyzed in starving specimens to determine the effects of the marine sponge on the food web of Kiel Bight, Germany. Analysis of silica uptake in Halichondria panicea populations from Kiel Bight indicated the presence of size-independent individual uptake variations. The uptake of silica by the marine sponge was not influenced by temperature. Furthermore, the uptake of silica by the marine sponge was an energy-consuming process that affected phytoplankton species composition during summers.

High radiogenic ratios of the lead isotopes 206Pb and 204Pb are present in in the megacrysts and melilitites of the Tertiary Urach volcanic field, in southwest Germany. High 207Pb/ 204Pb ratios indicate the absence of old crustal elements. Analysis of the composition of strontium isotopes indicates a long-term source evolution of the megacrysts. Neodymium isotopic ratios for the megacrysts and the melilitites are similar. The rare earth element compositions of the melilitites are similar to those in the ocean island basalts.

Metasomatism in the mantle xenoliths from Gees, West Eifel, Germany, occurs by silicate melts and the carbonatite metasomatism is almost absent. The silicate glass is present in almost all stages of transformations during metasomatism. The remnants of the upper mantle hybrid melts generate the Si-Al-enriched glasses of the xenoliths metasomatized by silicate melts. Ca-enrichment of the xenoliths may be due to low activities of silica.

Equilibration temperatures of 670-750 degrees centigrade and minimum metamorphic pressure of 1.6 GPa were evident in an examination of the petrology and geochronology of eclogites from the Variscan Schwarzwald in the Federal Republic of Germany. A fairly quick metamorphic evolution is likely. Several metamorphic phases during exhumation of the high-pressure rocks are established by reaction textures.

An analysis of data on major elements and 31 trace elements in olivine nephelinites, nepheline basanites, basanitic alkali olivine basalts and their differentiates reveals that a granitic partial melt from the wall rocks of magma chambers is responsible for contamination. This is evident from the Nd- and Sr-isotopic patterns of most of these differentiates from different regions in western Germany.

The north northeast directed thrusting on the East European Platform is caused by a Caledonain deformation, as indicated by a study of boreholes from the Isle of Rugen and the geophysical study of the nearby Baltic Sea. The Caledonain suture zone seems to have been reactivated during the post-Variscan events and hence formed the Romo-Mon Fault Zone. These Caledonian suture zones seem to have been formed during the Variscan age and are covered by Permian, Mesozoic and Cenozoic sequences.

An analysis describing eclogite-facies metasedimentary rocks is presented. The study examined a gneiss complex found in Munchberg, Germany. Examination showed that the formation contained CO2-N2 fluid inclusions with extremely low molar volumes in quartz. However, such rock types are often composed of H2O-rich inclusions correlating with amphibolite-facies conditions. It is shown that fluid composition variations generate local fluid gradients.

Heavy mineral analysis can play an important part in unraveling the extrabasinal (e.g., source area weathering) and intrabasinal processes (e.g., hydraulic processes) that influence the formation of clastic rocks. Various clastic (conglomerates, wackes, arenites, siltstones) and pyroclastic rocks (tuffs, ignimbrites, lahars) spanning the interval from the Upper Carboniferous through the Early Tertiary SE Germany (Bavaria) and the North German Basin were investigated for their transparent and opaque heavy minerals. The samples have been taken from drill cores, percussion holes and outcrops of various environments of deposition which are representative of a cross-section from the basin edge to the basin center (alluvial fan, braided streams, meandering to anastomosing fluvial drainage patterns, swamps, lakes, estuarine and nearshore-marine deposits). Routine heavy mineral analysis may be applied to heavy mineral separates in the grain size fraction from 0.020 mm to 0.200 mm, using heavy liquids of 2.95 g [ml.sup.-1]. The results furnish evidence that the strong points of this method lie in the fields of provenance analysis, paleoenvironmental analysis, and the study of volcanism and hydrothermal alteration. Routine heavy mineral analysis using the petrographic and ore microscope may successfully be combined with trace element analysis using ICPMS (e.g., REE, Th, U, Zr) and isotope studies (e.g., U, Pb). Radiometric age dating and the determination of the chemical composition of detrital apatite in late Paleozoic arenaceous rocks helped to pinpoint the type of source rocks and constrain the age of intrusion of the granites in the provenance area, from which the apatites were derived. This sedimentological method may be of interest to academicians and geologists working in the various fields of applied research alike (e.g., geoengineering, hydrogeology, exploration for hydrocarbons, uranium, coal and placer deposits). Keywords: Germany; heavy minerals; sediment geochemistry; provenance analysis; paleoenvironment; hydrothermal alteration

Conductivity data for pure crustal rocks which were recovered from boreholes in southern Germany reveal that accessory phases such as Fe-Ti oxides and sulphides can increase, or even exceed, the high conductivity level produced by saline fluids. This explains the high electrical conductivity of the lower continental crust as revealed by geophysical measurements.

Crustal strength is larger and resists lithospheric deformation when pore pressure is hydrostatic at mid-crustal depth, as indicated by laboratory friction studies and the study of faulting. Earlier theories held that continental crusts always had low average strengths and had no effect on the lithospheric deformation. The plate driving forces of the lithosphere are communicated through the upper crust, and hence a larger crustal strength resists changes in the lithosphere.

Exploring the Black Forest Photographically It is not because photographers can't find good photographic subject material in their own backyard or within close driving distance from their house, people just [...]

Loess research in Germany has a long tradition dating back to the early works of von Leonhard [von Leonhard, K.C., 1823/1824. Charakteristik der Felsarten. 3 Bde., 772 S. Heidelberg (J. Engelmann).] and his contemporary geoscientists. Ever since that time, German researchers and loess research within Germany have provided important contributions to the international `state of the art'. To date, however, perceptual 'unconformities' have existed in both the continuity of loess research in Germany and the interpretation of the loess record in both the palaeoecological and the stratigraphic sense. This paper briefly highlights some relevant periods of loess research in Germany and the approaches adopted, from the early days to the present. The development of a refined stratigraphy of the last glacial loess in Germany during the second half of the 20th century is reviewed in the contribution by A. Semmel. Fundamental contributions were first published by Schonhals, Freising and Brunnacker. In the course of the subsequent work of the Loess Commission of the International Union for Quaternary Research (INQUA), the stratigraphy of the Wurmian loess has since been refined in almost all loess regions of Germany, and schemes consistent in their fundamental features have been published. In recent years, contributions have focussed on age determination, in particular those based on luminescence dating techniques. Keywords: Loess; Germany; Unconformities

Reflected-light microscopy and fine-scale laser microRaman spectroscopy of shocked garnetcordierite-sillimanite gneisses in suevites of the Ries meteorite impact crater, Germany, led to the discovery of impact diamonds in their pristine graphite-diamond assemblages. Graphite-diamond textural relations permit a clear determination of the solid-state nature of the formation of diamond from graphite, which is estimated to have occurred at a peak-shock pressure between 30 and 40 GPa. Shock-induced transformations were promoted only in unkinked and undeformed graphite booklets at the graphite-garnet, graphite-sillimanite, or graphite-rutile interfaces, where the difference in shock impedance is very high. Reverberations of shock waves with short wavelengths similar to the grain sizes at the phase boundaries are probably important constraints for dynamic graphite-diamond phase transformation. Raman spectroscopic investigations of hard transparent carbon platelets intercalated between fine-grained diamond and deformed graphite revealed the platelets to be Raman inactive. The platelets are either dense amorphous carbon or an unknown dense crystalline carbon phase that is Raman inactive.

Microdiamonds associated with phlogopite, quartz, paragonite, phengite, apatite, and rutile are found as regular constituents of minute polyphase inclusions in garnet of ultrahigh-pressure (P) metamorphic gneiss lenses within migmatites of the gneiss-eclogite unit, Erzgebirge, Germany. These aggregates are interpreted to represent original inclusions of a supercritical dense COH fluid rich in K, Na, and Si[O.sub.2]. From this fluid, diamond was precipitated as a daughter crystal due to cooling at ultrahigh-P conditions. Brittle failure of the garnet host due to overpressure during release of confining pressure is demonstrated by healed radial cracks. During further cooling, the silicate phase assemblage of the inclusions crystallized at reduced internal pressures outside the stability field of diamond, as indicated by the presence of quartz, paragonite, and plagioclase. It is proposed that the mica-dominated mineral assemblage of the inclusions formed by reaction between the fluid and the garnet host, the previously formed diamond daughter crystals being preserved metastably. These diamond-bearing inclusions provide an unequivocal record of dense supercritical COH fluids rich in alkalies and silica within subducted continental crust during ultrahigh-P metamorphism. Keywords: diamond, ultrahigh-pressure metamorphism, supercritical fluid, inclusion, Erzgebirge.

Due to the low permeability and high ductility of rock salt, many salt diapirs, such as those in Germany and the Netherlands, are targeted as long-term repositories for disposal of high-level radioactive and chemical wastes. Geophysical and subsurface data show that the Gorleben salt diapir, which is one of the most extensively investigated diapirs in the world, and other salt diapirs of the Zechstein Formation in Germany contain large blocks (~80 m thick) of high-density anhydrite inclusions. These blocks, which were carried upward by the rising salt, are considered to be detached segments of intercalated layers that initially were deposited with the salt. Results of physical and numerical models, presented here, show that such detached, high-density blocks, which were entrained and carried upward by the diapir at an earlier stage, tend to sink in the late stages of diapiric evolution when the rate of diapiric rise slows down. During their descent, these high-density competent blocks deform by folding and create shear zones at the immediate contact with the less competent salt. The descending blocks initiate a secondary internal flow within the salt diapirs they descend, and they may deform any repository built within such diapirs, which would otherwise be considered as tectonically inactive. Keywords: salt diapir, hazardous waste, models, anhydrite blocks.

Obertiite is a new amphibole species from Bellerberg, Laccher See district, Eifel, Germany. It occurs with tridymite, fluororichterite, hematite, futile, aegirine-augite, kinoshitalite, and fluor-apatite in vugs in volcanic rocks, and crystallized from late-stage hydrothermal fluids associated with recent volcanism. Obertiite occurs as pale-pink elongated blades and divergent aggregates. It is brittle, H = 5, [D.sub.calc] = 3.16 g/[cm.sup.3], has a colorless streak, vitreous luster, and does not fluoresce; it has perfect cleavage on {110} and conchoidal fracture. In plane-polarized light, obertiite is slightly pleochroic in shades of pink to red-orange; X ^ a = 2 [degrees] (in [Beta] obtuse), Z = b, Y ^ c = 12 [degrees] (in [Beta] obtuse) with absorption X ~ Y ~ Z. It is biaxial negative, [Alpha] = 1.643(1), [Beta] =1.657(1), [Gamma] = 1.670(3), 2[V.sub.x] = 81(1) [degrees], no dispersion visible. Obertiite is monoclinic, space group C2/m, a = 9.776(2), b = 17.919(3), c = 5.292(1) [Angstrom], [Beta] = 104.05(2) [degrees], V = 899.3(3) [[Angstrom].sup.3], Z = 2. The strongest ten X-ray diffraction lines in the powder pattern are [d(I,hkl)]: 8.414(10,110), 2.705(7,331,151), 3.390(6,131), 4.467(5,040), 3.117(5,310), 2.531(5,202), 3.255(3,240), 2.577(3,061), 2.163(3,171,261), 4.013(2,111). Analysis by a combination of electron microprobe, SIMS, and crystal-structure refinement gives Si[O.sub.2] 54.53, [Al.sub.2][O.sub.3] 0.15, Ti[O.sub.2] 7.75, [Fe.sub.2][O.sub.3] 2.61, [Mn.sub.2][O.sub.3] 3.27, FeO 3.36, ZnO 0.08, MgO 14.13, [Li.sub.2]O 0.05, CaO 0.52, [Na.sub.2]O 9.51, [K.sub.2]O 0.98, F 0.55, [H.sub.2]O 0.20, O [equivalent] F -0.23, Ni, Cr, V, Cl not detected, sum 97.46 wt%. The formula unit, calculated on the basis of 24(O,OH,F) is ([MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII], and is close to the ideal end-member composition Na [Na.sub.2] ([Mg.sub.3][Fe.sup.3+][Ti.sup.4+]) [Si.sub.8] [O.sub.22] [O.sub.2]. The crystal structure of obertiite was refined to an R index of 2.6% using MoK[Alpha] X-ray intensity data. The M1 site is split into two subsites along the b axis, M1 and M1A; the M1 site is occupied by Mg, and M1A is occupied predominantly by [Ti.sup.4+] and [Mn.sup.3+]; M2 is occupied by Mg, [Fe.sup.2+], and [Fe.sup.3+], and M3 is occupied by Mg. Local bond-valence considerations suggest that [O.sup.2-] at O3 is linked to [Ti.sup.4+]Mg or [Mn.sup.3+][Mn.sup.3+] at the adjacent M1 and/or M1A sites, and that OH or F at 03 is linked to MgMg at the adjacent M1 sites.