Skip to content. | Skip to navigation

Personal tools

You are here: Home

Search results

RSS Subscribe to an always-updated RSS feed.

4822 items matching your search terms.
Filter the results.
Item type



































New items since



Sort by relevance · date (newest first) · alphabetically
Article Reference Magmatic, Magmatic-Hydrothermal, and Deformational Mineral Evolution of Spodumene Pegmatites from the Musha-Ntunga Area (Rwanda)
Pegmatites in the Mesoproterozoic Karagwe-Ankole belt of Central Africa are associated with large granitic complexes that were emplaced around 1 Ga. This study analyzes drill core samples of fresh albite-spodumene pegmatites from the Musha-Ntunga area (East Rwanda), spatially associated with the Lake Muhazi granitic pluton. We combine petrographic and cathodoluminescence microscopy with Raman spectroscopy and elemental geochemistry to study the paragenetic sequence, microtextural variations, and lithium distribution, from the magmatic and magmatic-hydrothermal stages to the hydrothermal stage and during deformation processes. Five textural types of spodumene are distinguished. Coarse-grained spodumene type 1 and symplectitic type 2 are interpreted to have formed during primary magmatic crystallization, whereas spodumene types 3 and 4 formed during magmatic-hydrothermal alteration. Deformation locally affected the pegmatite intrusions. Spodumene type 1 crystals deformed in a brittle and ductile manner, displaying sigma-clast-shaped porphyroclasts (“spodumene fish”) and boudinage textures. The large strained spodumene crystals were also partially recrystallized to fine-grained elongated crystals (type 5), which occur in bands along with mica, quartz, and apatite and define the main orientation of foliation. Montebrasite occurs both as a late primary magmatic phase with spodumene and as a secondary phase that recrystallized during magmatic-hydrothermal alteration and deformation. Eucryptite, lithiophilite, and cookeite occur as late-stage hydrothermal phases, replacing primary lithium assemblages. Associated phases muscovite, apatite, microcline, albite, quartz, and columbite-tantalite further demonstrate the transition from a magmatic to a (magmatic-)hydrothermal and deformational regime. Elevated lithium contents in tourmaline within the metasedimentary host rock indicate dispersion of lithium into the host rock during pegmatite emplacement, subsequent crystallization, and alteration. The results of this multimethod approach demonstrate that different generations of lithium-bearing minerals and associated textures not only record the full transition from a magmatic to hydrothermal regime but also document deformation-related processes that can impact the distribution of metals within pegmatites.
Located in Library / RBINS Staff Publications 2025
Article Reference Magura Cave, Bulgaria: A multidisciplinary study of Late Pleistocene human palaeoenvironment in the Balkans
Abstract Two trenches excavated at Magura Cave, north-west Bulgaria, have provided Late Pleistocene lithic artefacts as well as environmental evidence in the form of large and small mammals, herpetofauna and pollen recovered from Crocuta coprolites. One of the trenches also has a visible tephra layer which has been confirmed as representing the major Campanian Ignimbrite eruption and is accurately dated at the source area to 39,280 ± 55 yrs and radiocarbon determinations have added to chronological resolution at the site. The palaeoenvironment of the region during the Late Pleistocene is discussed in the context of hominin presence and shows a mosaic landscape in a region considered a crucial refugium for both plants and mammals, including hominins.
Located in Library / RBINS Staff Publications 2016
Article Reference Mainstreaming biodiversity conservation into development cooperation—highlights from an ALTER-NET-EKLIPSE workshop
Located in Library / RBINS Staff Publications 2020
Article Reference Major excursions in sulfur isotopes linked to permafrost change in Eurasia during the last 50,000 years.
We identify a major sulfur isotope excursion in Eurasian faunal bone collagen from the last 50,000 years, here termed the Late Pleniglacial Sulfur Excursion. Our analysis suggests this is linked to changing permafrost conditions, presenting the utility of faunal collagen δ34S as a proxy for permafrost dynamics, a critical component of the global carbon cycle. Our findings complicate the use of archaeological faunal sulfur isotopes for mobility and palaeodietary studies.
Located in Library / RBINS Staff Publications 2025
Article Reference Octet Stream Making sense of variation in sclerochronological stable isotope profiles of mollusks and fish otoliths from the early Eocene southern North Sea Basin
Stable isotope sclerochemistry of biogenic carbonate is frequently used for the reconstruction of paleotemperature and seasonality. Yet, few studies have compared intra-and inter-taxon isotope variability and variation within a single depositional environment. We measured seasonal changes in δ18O and δ13C compositions in multiple specimens of two carditid bivalve species, a turritelline gastropod species, and two species of otoliths from demersal fish, from two early Eocene (latest Ypresian, 49.2 Ma) coquinas in the inner neritic Aalter Formation, located in the Belgian part of the southern North Sea Basin (paleolatitude ∼41°N). Results demonstrate considerable variation among taxa in the mean, amplitude, and skewness of δ18O and δ13C values from sequentially sampled growth series. We attribute this variation to factors including differences in seasonal growth over ontogeny, mixing of depositional settings by sediment transport, differences between sedentary and mobile organisms, and differences in longevity of the taxa in question. Growth cessation during winters in turritellines and fishes in particular lead to an incomplete representation of the seasonal cycle in their growth increments, in comparison to carditid bivalves. Ophidiid fish otolith isotope records appear to reflect environmental conditions over a wider range of habitats and environments, and we infer this is due to a combination of sedimentary transport, as these are small structures, and postmortem transport by free-swimming predatory fish. Our study highlights the potential variability encompassed by taxa in the shallow marine realm even when they are found in the same deposits. While this has significant implications for seasonality reconstructions based on conventional isotope profiles, we show that careful study of the ecology and ontogeny of multiple taxa and specimens within a death assemblage can reveal sources of variation and yield a close approximation of conditions in the setting of interest.
Located in Library / RBINS Staff Publications 2025
Article Reference Malachite, an indicator of major Pliocene Cu remobilization in a karstic environment (Katanga, Democratic Republic of Congo)
Located in Library / No RBINS Staff publications
Article Reference Malacological inventory of a sediment sample collected around the 500-meter isobath, southwest of Iceland
Located in Library / RBINS Staff Publications 2025
Article Reference Male spiders control offspring sex ratio through greater production of female-determining sperm
Located in Library / RBINS Staff Publications 2018
Article Reference Mammalian remains from the Upper Palaeolithic site of Kamenka, Buryatia (Siberia)
Located in Library / RBINS Staff Publications
Article Reference Mammals from the Paleocene-Eocene transition in Belgium (Tienen Formation, MP7): Paleobiogeographical and biostratigraphical implications
Located in Library / RBINS Staff Publications