A5079288049- Geological and Geochemical Analysis
- Geological Formations and Processes Exploration
- earthquake and tectonic studies
- Geomagnetism and Paleomagnetism Studies
- High-pressure geophysics and materials
- Geology and Paleoclimatology Research
- Paleontology and Stratigraphy of Fossils
- Geological Modeling and Analysis
- Geochemistry and Geologic Mapping
- Hydrocarbon exploration and reservoir analysis
- Geological formations and processes
- Astro and Planetary Science
- Rock Mechanics and Modeling
- Marine and environmental studies
- Pleistocene-Era Hominins and Archaeology
- Geological Studies and Exploration
- Landslides and related hazards
- Geological and Tectonic Studies in Latin America
Charles University
2015-2025
Czech Academy of Sciences, Institute of Geology
2015-2025
Czech Academy of Sciences
2014-2024
Abstract This paper summarizes the current knowledge on nature, kinematics and timing of movement along major tectonic boundaries in Bohemian Massif demonstrates how Variscan plutonism deformation evolved space time. Four main episodes are recognized: (1) Late Devonian–early Carboniferous subduction continental underthrusting Saxothuringian Unit beneath Teplá–Barrandian resulted orogen-perpendicular shortening growth an inboard magmatic arc during c. 354–346 Ma; (2) subduction-driven was...
Abstract The thermal evolution of magmatic systems the Altenberg‐Teplice and Tharandter Wald calderas, which erupted during terminal post‐collisional phase Variscan orogeny in Bohemian Massif, was investigated. zircon saturation temperatures Ti‐in‐zircon thermometer indicate that intrusive extrusive units two calderas were sourced from medium‐ to high‐temperature (∼770–930°C) felsic lower crustal magma. Using an integrated rock‐magnetic paleomagnetic approach through demagnetization stepwise...
Timing of magmatic activity the late-Variscan Altenberg–Teplice Caldera was rather vaguely constrained. In this paper, we present five new laser ablation inductively coupled plasma mass spectrometry (LA–ICP–MS) U–Pb zircon ages, which along with published data indicate ~13 Myr lifetime. Formation commenced emplacement pre-caldera pluton at ~325–319 Ma, and terminated intrusion syn-collapse ring dykes post-collapse granites ~312 Ma. The main ignimbrite volcanism in area ATC occurred ~318–313...
The North American Cordillera is a classic example of accretionary orogen, consisting multiple oceanic terranes attached to the western margin Laurentia during Mesozoic times. Although linear for most parts, terrane boundaries are at high angle overall structural grain in several segments which has been matter longstanding controversy as how and when these orogenic curvatures formed. This paper discusses mechanisms, kinematics, timing initiation one major curvatures, Blue Mountains Province...
The Minarets caldera is a volcano–plutonic complex in the Sierra Nevada, California, that exemplifies interactions between volcanism and tectonic deformation continental-margin arcs. Caldera evolution commenced with emplacement of pre-collapse rhyolitic ash-flow tuff, followed by collapse deposition volcanic breccia rhyodacitic tuff. Subsequently, rocks were deformed along regional Bench Canyon shear zone. centre was then intruded resurgent c. 100 Ma steep-sided Shellenbarger granite pluton,...
Research Article| November 21, 2018 Emplacement dynamics of syn-collapse ring dikes: An example from the Altenberg-Teplice caldera, Bohemian Massif Filip Tomek; Tomek † 1The Czech Academy Sciences, Institute Geology, Rozvojová 269, Prague, 16500, Republic2Institute Geology and Paleontology, Faculty Science, Charles University, Albertov 6, 12843, Republic †filip.tomek@gmail.com Search for other works by this author on: GSW Google Scholar Jiří Žák; Žák 2Institute Martin Svojtka; Svojtka Fritz...
Abstract The relation of plate kinematics to the structural record arc plutons and their host rocks is complex still not fully understood. We address this issue through a combination field mapping, analysis, anisotropy magnetic susceptibility fabric modeling in Late Cretaceous Tuolumne Intrusive Complex, Sierra Nevada, California. A pattern anti‐clockwise rotation from ∼NNW–SSE WNW–ESE steep foliations change ellipsoid shape oblate prolate was revealed successively emplaced Kuna Crest...
Contrasting magnetic fabrics in five successively emplaced syntectonic plutons reveal temporal and spatial variations tectonic strain the oceanic terranes of Blue Mountains province, northeastern Oregon, during Late Jurassic to Early Cretaceous. The inferred regimes changed from: (1) thrusting sinistral shearing at ca. 160 Ma, (2) horizontal stretching 147 Ma (in forearc–accretionary wedge Baker terrane), (3) dextral transpression that started from 140 onward was associated with progressive...
Multiple magnetic fabrics, referred to as F1–F5, were revealed through the anisotropy of susceptibility in an Ocean Plate Stratigraphy (OPS) mélange Neoproterozoic–Cambrian Blovice accretionary complex, Bohemian Massif. The fabrics post-date formation and rotation basalt blocks within matrix are interpreted terms a complex structural history mélange. Excluding local F1 fabric formed earlier along belt, recording shortening wedge front, whereas higher grade F4 pervasively overprinted both SW...
Abstract Many eroded calderas expose associated postcollapse plutons, but detailed fieldwork‐supported studies have rarely focused on the internal structure that can contribute to understanding of emplacement dynamics. The Alamosa River monzonite pluton is a intrusion at Platoro caldera complex erupted six large ignimbrites between 30.2 and 28.8 Ma in Southern Rocky Mountains volcanic field. Magnetic fabrics this indicate pulsed vertically extensive pluton. magmatic pulses are documented by...
The evolution of eruptive vents related to calderas is not fully understood. We focus on a structural, rock-magnetic and geochemical investigation 314 Ma rhyolite dyke swarm associated with the late-orogenic Altenberg–Teplice Caldera, Bohemian Massif, eastern Variscan belt. whole-rock major element, trace element Nd–Pb isotope geochemistry along published U–Pb zircon geochronology link extra-caldera intra-caldera ignimbrites. magnetic fabrics determined using anisotropy susceptibility are...