Grzegorz Ziemniak

Grzegorz Ziemniak
University of Wroclaw | WROC · Instytut Nauk Geologicznych

PhD

About

13
Publications
2,057
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
36
Citations
Citations since 2016
13 Research Items
36 Citations
2016201720182019202020212022051015
2016201720182019202020212022051015
2016201720182019202020212022051015
2016201720182019202020212022051015

Publications

Publications (13)
Article
Full-text available
The northern extent of the Scandinavian Caledonides includes the Skibotn Nappe Complex of still debated structural position. This paper is focused on part of this complex and presents new U-Th-total Pb monazite dating results for the migmatitic gneiss of the Kåfjord Nappe. The rocks show mineral assemblage of garnet + plagioclase + biotite + white...
Article
Full-text available
The timing of Svalbard’s assembly in relation to the mid‐Paleozoic Caledonian collision between Baltica and Laurentia remains contentious. The Svalbard archipelago consists of three basement provinces bounded by N‐S‐trending strike‐slip faults whose displacement histories are poorly understood. Here, we report microstructural and mineral chemistry...
Article
Full-text available
Geochronology of Th-rich minerals is advantageous as it allows use of three isotopic systems (i.e., ²⁰⁶Pb/²³⁸U, ²⁰⁷Pb/²³⁵U, and ²⁰⁸Pb/²³²Th) for accurate data assessment. The ²⁰⁸Pb/²³²Th system is especially advantageous in cases where the dated mineral includes an initial Pb component, as ²⁰⁸Pb/²³²Th is the least sensitive to the effects of initia...
Article
The Arctic archipelago of Svalbard, Norway, plays an important role in tectonic reconstructions of the Cambrian–Devonian Caledonian orogen in the North Atlantic and circum-Arctic regions. To elucidate the Proterozoic geological history of the Southwestern Basement Province of Svalbard and place its origin and displacement history in the context of...
Article
Detrital zircon provenance studies of Precambrian metasedimentary rocks in Wedel Jarlsberg Land and Sørkapp Land, Svalbard’s Southwestern Caledonian Basement Province, were conducted to evaluate local stratigraphic correlations and the role of long-distance strike-slip displacements in assembling the basement of the Arctic Caledonides. The detrital...
Article
Full-text available
The Scandinavian Caledonides comprise nappe stacks of far-travelled allochthons that record the opening and closure of the Iapetus Ocean, culminating with the collision of Baltica and Laurentia. The Seve Nappe Complex (SNC) of the Scandinavian Caledonides comprises relics of the outermost Baltoscandian passive margin that were subducted to mantle d...
Article
The Collisional Orogeny in the Scandinavian Caledonides (COSC) scientific drilling project focuses on mountain building processes in a major mid-Paleozoic orogen in western Scandinavia and its comparison with modern analogues. The transport and emplacement of subduction-related highgrade continent-ocean transition (COT) complexes onto the Baltoscan...
Conference Paper
Full-text available
The central segment of the Scandinavian Caledonides is abundant in outcrops of orogenic ultramafic bodies. This study focuses on ultramafic rocks from the Seve Nappe Complex (SNC) in the northern part of Swedish Jämtland county, representing the hypothetical outermost margin of Baltica. The studied bodies of ultramafics range in size from meters...
Conference Paper
Svalbard of the High Arctic records multiple tectonic events from Proterozoic to Paleogene. It is divided into three fault-bounded provinces with contrasting tectonometamorphic histories. The Southwestern Province possesses two ductile shear zones that each sinistrally juxtaposes Neoproterozoic amphibolite facies rocks against greenschist facies ro...

Network

Cited By

Projects

Projects (3)
Project
Many studies of continental growth and modification have focused on the major phase of growth in the early history of the Earth, but a major goal of our proposed study is to investigate an important, but hitherto little-recognised example of more recent (Phanerozoic) continental growth by accretion in a subduction-collision system – the Caledonian orogen of Scandinavia. Here, crust generated in arcs, back-arcs, fore-arcs and mid-ocean ridges within the Iapetus Ocean has been accreted to the Baltic craton by a combination of arc collisions and final continental collision with Laurentia. The accreted rocks are now preserved in the Köli Nappe Complex (KNC) in Sweden and Norway.
Project
ArcTec proposes to study (1) the westward extent, kinematics and timing of formation, and (2) reactivation–overprint of Timanian (i.e., ca. 600 million years old) faults during subsequent tectonic events in the Arctic, and to (3) insert these faults into a detailed tectonic evolution model for Svalbard, the northwestern Barents Sea and the Fram Strait. The project involves a collaboration between four researchers at UiO (Dr. Koehl and Dr. Anell), McGill University (Canada; Prof. Halverson), and BGR (Germany; Dr. Klitzke). Thus far, remnants of Timanian metamorphism and basement were identified in southwestern (Majka et al., 2008) and northwestern Spitsbergen (Dallmeyer et al., 1990), and a regional (Torrelian) unconformity between Proterozoic and (latest Neoproterozoic–) lower Paleozoic metasedimentary rocks in southwestern and northeastern Spitsbergen, Bjørnøya and Nordaustlandet coeval with Timanian metamorphism suggests major tectonic reorganization occurred in the late Neoproterozoic (Horn and Orvin, 1928; Harland et al., 1992). ArcTec will focus on newly identified WNW–ESE faults and basement heterogeneities in Svalbard and the northern Barents Sea, and combine geophysical (magnetic, gravimetric, bathymetric, seismic) datasets, structural and sedimentological fieldwork, and petrological and geochronological analyses to address the targeted objectives. ArcTec will investigate the impact of WNW–ESE faults on the exhumation–burial history of Svalbard and the northwestern Barents Sea margin, and their relationship with amphibolite facies metamorphism of Timanian age, with the Torrelian unconformity in southwestern and northeastern Spitsbergen and western Nordaustlandet, and with older (e.g., Grenvillian) and younger (e.g., Caledonian and Eurekan) structures and fabrics, such as crosscutting and controlling–controlled relationships (inheritance).
Project
It is widely accepted that the Iapetus Ocean opened in the latest Neoproterozoic, but the exact timing of this event is still debated. Nearly all evidence for such timing and reasoning about it are based on geochronological data obtained from mafic igneous rocks and their contact aureoles. However, the question arises whether the timing of this voluminous igneous activity is indeed representative for true opening of the Iapetus. If so, do we have a stratigraphic record of this event? Even more importantly, what was the role and where was located the centre of the mantle plume that was supposed to contribute to the Iapetus opening process ? To answer these questions, we propose to focus on the Neoproterozoic to Cambrian evolution of Baltica and possible peri-Baltican terranes.