18 research outputs found
U-Pb zircon age of the youngest magmatic activity in the High Tatra granites Central Western Carpathians
Detailed cathodoluminescence (CL) imaging of zircon crystals, coupled with Laser Abla-tion Multi-Collector Inductively Coupled Plasma Mass Spectrometry (LA-MC-ICP-MS) U-Pb zircon dating was used to develop new insights into the evolution of granitoids from the High Tatra Moun-tains. The zircon U-Pb results show two distinct age groups (350±5 Ma and 337±6 Ma) recorded from cores and rims domains, respectively. Obtained results point that the last magmatic activity in the Ta-tra granitoid intrusion occurred at ca. 330 Ma. The previously suggested age of 314 Ma reflects rather the hydrothermal activity and Pb-loss, coupled with post-magmatic shearing
Geochronology and petrogenesis of granitoid rocks from the Goryczkowa Unit, Tatra Mountains (Central Western Carpathians)
The geochemical characteristics as well as the LA-MC-ICP-MS U-Pb zircon age relationship between two granitoid suites found in the Goryczkowa crystalline core in the Western Tatra Mountains were studied. The petrological investigations indicate that both granitoid suites were emplaced at medium crustal level, in a VAG (volcanic arc granites) tectonic setting. However, these suites differ in source material melted and represent two different magmatic stages: suite 1 represents a high temperature, oxidized, pre-plate collision intrusion, emplaced at ca. 371 Ma while suite 2 is late orogenic/anatectic magma, which intruded at ca. 350 Ma. These data are consistent with a period of intensive magmatic activity in the Tatra Mountain crystalline basement. The emplacement of granitoids postdates the LP-HT regional metamorphism/ partial melting at ca. 387 Ma and at 433-410 Ma, imprinted in the inherited zircon cores
Magma hybryzidation in the Western Tatra Mts. granitoid intrusion (S-Poland, Western Carpathians)
In the Variscan Western Tatra granites hybridization
phenomena such as mixing and mingling can be observed
at the contact of mafic precursors of dioritic composition and
more felsic granitic host rocks. The textural evidence of
hybridization include: plagioclase–K-feldspar–sphene ocelli,
hornblende- and biotite-rimmed quartz ocelli, plagioclase
with Ca-rich spike zonation, inversely zoned K-feldspar
crystals, mafic clots, poikilitic plagioclase and quartz crystals,
mixed apatite morphologies, zoned K-feldspar phenocrysts.
The apparent pressure range of the magma hybridization
event was calculated at 6.1 kbar to 4.6 kbar, while the
temperature, calculated by independent methods, is in the
range of 810°C−770°C. U-Pb age data of the hybrid rocks
were obtained by in-situ LA-MC-ICP-MS analysis of zircon.
The oscillatory zoned zircon crystals yield a concordia age of
368±8 Ma (MSWD=1.1), interpreted as the age of magma
hybridization and timing of formation of the magmatic
precursors. It is the oldest Variscan magmatic event in that
part of the Tatra Mountains
Cadomian protolith ages of exotic mega blocks from Bugaj and Andrychów (Western outer Carpathians, Poland) and their palaeogeographic significance
This study presents the first zircon U-Pb LA-MC-ICP-MS ages and whole-rock Rb/Sr and Sm/Nd data from exotic blocks (Bugaj and Andrychów) from the Western Outer Carpathians (WOC) flysch. The CL images of the zircon crystals from both samples reveal typical magmatic textures characterized by a well-defined concentric and oscillatory growth zoning. A concordia age 580.1 ± 6.0 Ma of the zircons from the Bugaj sample is considered to represent the crystallization age of this granite. The zircon crystals from the Andrychów orthogneiss yield an age of 542 ± 21 Ma, in-terpreted as the uppermost Proterozoic, magmatic crystallization age of the granitoid protholith. The initial (at ca. 580 Ma) 87Sr/86Sr ratios of the Bugaj granitoids (0.72997 and 0.72874) are highly radio-genic, pointing to the assimilation of an older, possibly strongly Rb enriched source to the Bugaj melt. The Nd isotope systematics (εNd580 –1.4 and 0.4) also point to a significant contribution of such a dis-tinct mantle source. On the basis of the sequence of magmatic events obtained from U-Pb zircon ages, we suggest that exotic mega blocks deposited to the WOC basins were related to the Brunovistulicum Terrane. They belong to the group of Vendian/Cambrian granitoids representing the latest, post-tectonic expression of the Cadomian cycle
Episodic construction of the Tatra granitoid intrusion (Central Western Carpathians, Poland/Slovakia) : consequences for the geodynamics of Variscan collision and Rheic Ocean closure
The Tatra granitoid pluton (Central Western
Carpathians, Poland/Slovakia) is an example of composite
polygenetic intrusion, comprising many magmatic pulses
varying compositionally from diorite to granite. The U–
Pb LA-MC-ICP-MS zircon dating of successive magma
batches indicates the presence of magmatic episodes at 370–
368, 365, 360, 355 and 350–340 Ma, all together covering a
time span of 30 Ma of magmatic activity. The partial resorption
and recycling of former granitoid material (“petrological
cannibalism”) was a result of the incremental growth
of the pluton and temperature in the range of 750–850 °C.
The long-lasting granitoid magmatism was connected to
the prolonged subduction of oceanic crust and collision of
the Proto-Carpathian Terrane with a volcanic arc and finally
with Laurussia, closing the Rheic Ocean. The differences in
granitoid composition are the results of different depths of
crustal melting. More felsic magmas were generated in the
outer zone of the volcanic arc, whilst more mafic magmas
were formed in the inner part of the supra-subduction zone.
The source rocks of the granitoid magmas covered the compositional
range of metapelite–amphibolite and were from
both lower and upper crust. The presence of the inherited
zircon cores suggests that the collision and granitoid magmatism
involved crust of Cadomian consolidation age (c.
530 and 518 Ma) forming the Proto-Carpathian Terrane, crust of Avalonian affinity (462, 426 Ma) and melted metasedimentary
rocks of volcanic arc provenance
Variscan post-collisional cooling and uplift of the Tatra Mountains crystalline block constrained by integrated zircon, apatite and titanite LA-(MC)-ICP-MS U-Pb dating and rare earth element analyses
LA-ICP-MS U-Pb dating of apatite, titanite and zircon from the metamorphic cover of the Western Tatra granite
was undertaken to constrain the timing of metamorphic events related to the final stages of Variscan orogenesis
and subsequent post-orogenic exhumation. Zircon was found only in one sample from the northern metamorphic
envelope. U-Pb ages from the outermost rims of zircons define a concordia age of 346 ± 6 Ma, while the inner
rims yield a concordia age of 385 ± 8 Ma. Apatite from three samples from the northern metamorphic envelope
yield U-Pb ages of 351.8 ± 4.4 Ma, 346.7 ± 5.9 Ma and 342.6 ± 7.1 Ma. Titanite from an amphibolite from
the southern metamorphic envelope yields a U-Pb age of 345.3 ± 4.5 Ma. The age of c. 345 Ma is interpreted to
represent the climax of metamorphism and the onset of simultaneous exhumation of the entire Tatra Mountains
massif, and is recorded mainly in the northern part of the metamorphic cover.
In the southern metamorphic envelope, distinct populations of apatite can be recognized within individual
samples based on their rare earth element (REE) and actinide contents. One population of apatite (Ap1) yields a
relatively imprecise U-Pb age of 340 ± 31 Ma. This population comprises apatite grains with very similar trace
element compositions to apatite in the northern amphibolite samples, which suggests they crystallized under
similar metamorphic conditions to their northern counterparts. A second apatite population (Ap2) yields an age
of c. 328 ± 22 Ma, which is interpreted as neocrystalline apatite that formed during a late-Variscan (hydrothermal?)
process involving (P, F, Ca, REE)-rich fluid migration. The youngest generation of apatite (Ap3) yields
a U-Pb age of 260 ± 8 Ma and may have resulted from thermal resetting associated with the regional emplacement
of Permian A-type granites. The proposed tectonic model assumes that rapid uplift (and cooling) of the
Tatra block initiated at ca. 345 Ma, contemporaneous with anatexis. Subsequent fluid migration, possibly facilitated
by extension related to the opening of Paleo-Tethys, affected only the southern part of the Tatra block
Geneza i zasięg vistuliańskiego zespołu terasowego Odry-Osobłogi pod Krapkowicami
The system of morphological levels occurs on the slopes of the Odra and Osobłoga valleys in the vicinity of Krapkowice, southern Poland. Their genesis, range and age have been the subject of lively scientific discussion since the 1930s. Geomorphological analysis confirmed the fluvial origin of these flats. The use of LIDAR data allowed for precise height determination and revision of the range of indivi-dual river terraces, which rise above the valley bottom to a height of about 166 m a.s.l. (more or less 6 m above the Osobłoga/Odra channel), 168 m a.s.l. (8 m), 172 m a.s.l. (12 m), 174 m a.s.l. (14 m) and 181 m a.s.l. (21 m) res-pectively. The dating of sediments building the terrace elevated to 172 m a.s.l. using the OSL-SAR method gave a result of 87.7 ± 5.7 ka (GdTL-2820) indicating that it originated from the last cold stage of the Pleistocene. The ter-race surface was shaped by a sand-gravel braided river, which has developed on the substratum of the alluvium do-cumenting the period of intense valley-floor aggradation
Continuous magma mixing and cumulate separation in the High Tatra Mountains open system granitoid intrusion, Western Carpathians (Poland/Slovakia) : a textural and geochemical study
In this study the formation of the polygenetic High Tatra granitoid magma is discussed. Felsic and mafic magma mixing and mingling processes occurred in all magma batches composing the pluton and are documented by the typical textural assemblages, which include: mafic microgranular enclaves (MME), mafic clots, felsic clots, quartz-plagioclase-titanite ocelli, biotite-quartz ocelli, poikilitic plagioclase crystals, chemically zoned K-feldspar phenocrysts with inclusion zones and calcic spikes in zoned plagioclase. Geochemical modelling indicates the predominance of the felsic component in subsequent magma batches, however, the mantle origin of the admixed magma input is suggested on the basis of geochemical and Rb-Sr, Sm-Nd and Pb isotopic data. Magma mixing is considered to be a first-order magmatic process, causing the magma diversification. The cu-mulate formation and the squeezing of remnant melt by filter pressing points to fractional crystallization acting as a second-order magmatic process
O harmonijny rozwój człowieka. Myśl pedagogiczna Profesora Andrzeja Jaczewskiego
Z wprowadzenia: "Andrzej Jaczewski, Profesor Honorowy Krakowskiej Akademii im. Andrzeja
Frycza Modrzewskiego w Krakowie, uczony, który we wrześniu b.r. ukończy
90. rok życia, to najstarszy i jeden z nielicznych obecnie autorytetów naukowych
w dziedzinie badań nad rozwojem seksualnym dzieci i młodzieży. Jego działalność
sytuuje się na pograniczu nauk medycznych i pedagogicznych."(...