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Multiple tools have been used to determine the sensitivity of phosphates from the early Archaean Barberton greenstone belt to transformation. The assessment of the degree of transformation is crucial for verifying data about the parameters of the paleo-environment. From the obtained results, three generations of phosphates can be distinguished. Group A is observed in cherts and banded iron formation BIF early-generation fluor-hydroxyapatite that precipitated from seawater. It is characterized by flat rare earth element (REE) patterns with a positive Eu anomaly and high Y/Ho ratio in the range of 54–70. Apatites in this group lack any visible indicators of secondary alterations at the micro- and nanoscales. Fourier transform infrared spectra indicate that these apatites are relatively rich in water, and, due to cationic substitution, their OH-stretching regions exhibit complex ordering and numerous component bands. The characteristics observed in the cherts and silicified felsic volcaniclastics of group B imply advanced metasomatic alteration. They exhibit light and heavy REE depletion and an absence of water in the halogen site. Nanoscale investigations reveal cracks, pores, nanofluid inclusions and nanochannel-like structures, as well as inclusions. Group C is represented by igneous-derived apatites that partially reflect their igneous origin. The phosphates are predominantly fluorapatite with typical magmatic apatite REE distribution patterns. Imaging at the micro- and nanoscales indicates that they partially preserve the signature of igneous origin. It seems that some of the analyzed apatite partially preserved their primordial features; therefore, they might be used for the reconstruction of Archaean abiotic systems.

The western part of the late Variscan Strzegom–Sobótka massif exemplifies an intrusion that formed in a multi-component system. The system shows ambiguous isotopic and geochemical signatures and presents a seemingly composite character [biotite granite with negligible amount of hornblende (HBG) and microgranular mafic enclaves (MMEs)]. The melts responsible for forming granitic rock and its MMEs were not derived from contrasting crustal and mantle sources but from different crustal domains. These melts exhibit hybrid characteristics due to subsequent contamination processes. The data suggest two different stages of hybridization of two geochemically distinct magmas corresponding to granite and enclaves. The processes were temporally and spatially distinct. Heterogeneous protoliths and hybridization made these magma isotopic signatures and trace element patterns ambiguous. The main mechanism involved in developing granitic rocks was fractional crystallization (FC); the mechanism responsible for MME composition was mixing, but other local processes were also involved in rock formation. Generally, the FC signature was not obscured by the hybrid mafic melt input. This felsic-mafic melt interaction was a limited one-sided process. Granitic melt was changed by the presence of small mafic magma blobs, but their influence on granite crystallization was negligible. The massif is thus an ideal example of an environment where MMEs coexist with a granitic body, although MMEs do not determine the actual composite character of the pluton. The early stage of Variscan pluton formation within the Bohemian Massif and adjacent areas was shaped by interacting mantle- and crust-derived melts. The pluton described in this paper belongs to the late stage of Variscan magmatism. It is a multi-component system shaped by the participation of melts derived from heterogeneous crustal domains. The presence of enclaves does not explicitly indicate their dominant role in the formation of composite plutons of crust-mantle origin. It is decisive to determine whether the ambiguous signatures appearing in such cases truly indicate both of these sources.

The results of the new Electron Microprobe Analysis of apatite, hornblende and biotite crystals of the hornblende-biotite variety of the Strzegom-Sobótka granite indicate that these rocks experienced several phases during their evolution. During the first phase, the melting of the continental crust was caused by heating from basaltic magma. Nevertheless, the system was closed, and there is no evidence of the influence of any mafic component. The volatile compositions of apatite crystals recorded the signature of this phase. Afterwards, small quantities of mafic material were delivered into the crystallizing melt by ascending basaltic magma. The volatile composition of hornblende, together with dramatic changes in the F/Cl ratios between apatite and hornblende, indicates that the injection of mafic material occurred between the crystallization of both minerals. During the crystallization of hornblende, the system was closed. During the last episode, the volatile composition recorded by biotite indicates that the system opened again. This is represented by the decrease of Cl in the melt. Moreover, the estimated F concentrations in the melt range from ~2000 to ~3000 ppm and do not change significantly within the crystallization interval, whereas the Cl concentrations decreased from 1470-900 ppm at 829-768 °C to as low as 100 ppm at 710-650 °C, most likely due to the continuous exsolution of aqueous fluid from silicate melt or the crystallization of Cl-bearing minerals.

CHOMIK is the name of a penetrator constructed for sampling and retrieval of Phobos surface material. It formed an integral part of the Phobos Sample Return Mission. In this paper we present its construction and intended mode of operation, since the concept is still viable for future missions either to Phobos or to other small bodies of similar dimensions. We take Phobos as an example to describe the science case for such an instrument and how it might be utilized to resolve important open issues regarding the origin of the Martian moons. Concerning the latter, we place emphasis on measurement techniques and analysis tools for mapping trace element concentrations in returned sample.

Alkali feldspar megacrysts from the porphyritic Karkonosze granite (Western Sudetes, Poland) were formed during magma mixing. Barium concentrations in zoned crystals, a sensitive indicator of feldspar migration between coeval magmas, serve to reconstruct the crystallization path of the megacrysts. Based on geochemical data, a double mixing model for the formation of the porphyritic granite and for megacryst growth is constructed. The feldspar growth model supports megacryst nucleation and early crystallization in a hybridized crustal magma of granodioritic composition. The growth model gives credibility of the choice of partition coefficients used in the modelling. Insights gained from mixing models based on whole rock composition and mineral zonation allow the recognition of various hybridization events that are reflected in a variety of megacryst crystallization paths within the pluton. [PUBLICATION ABSTRACT]

: The relationship between suicide and creativity has long been a subject of considerable concern. The author presents evidence indicating that in fact depression, suicide, and creativity are related. Several hypotheses for the relationship are posited. It is suggested that the same changes in the serotonergic system that are associated with depression in general and with impulsive suicides and homicides in the extreme may also be responsible for an element of risk taking that characterizes creativity and innovation in a person psychodynamically predisposed to being creative.