0000000000651511

AUTHOR

Wolfgang Siebel

Carboniferous high-potassium I-type granitoid magmatism in the Eastern Pontides: The Gümüşhane pluton (NE Turkey)

The Gumushane pluton, a high-K calc-alkaline I-type granodionte/granite complex, forms an important component of the pre-Liassic basement of the Eastern Pontides (NE Turkey) In its eastern part, the pluton shows a compositional zonation ranging from biotite-hornblende granodiorite in the NW through biotite-hornblende granite to leucogranite/granophyre in the SE Numerous mafic microgranular enclaves (up to similar to 40 cm in diameter) suggest the former presence of globules of mafic melt during crystallization Emplacement of the pluton occurred during the latest Early Carboniferous, as shown by the 320 +/- 4 Ma Ar-40-Ar-39 bionte/homblende and 324 +/- 6 Ma LA-ICP-MS U-Pb zircon ages. In Har…

research product

Post-collisional adakite-like magmatism in the Ağvanis Massif and implications for the evolution of the Eocene magmatism in the Eastern Pontides (NE Turkey)

In the Anatolia, the Caucasus and northwest Iran, the Eocene epoch is characterized by widespread basic to acidic magmatism, whose temporal and spatial evolutions and origin are poorly understood. In this paper, we provide geochronological and geochemical data on a suite of Early Eocene intrusions from northeast Turkey and discuss their origin within a regional tectonic framework. Post to late-collisional, moderate to small bodies of quartz diorite and leucogranodiorite as well as later dacite porphyries intrude Permo-Triassic low-grade metamorphic rocks in the southern part of the Eastern Pontides very close to the Neo-Tethyan Izmir-Ankara-Erzincan suture. In places, the intrusives display…

research product

“Celtic migrations”: Fact or fiction? Strontium and oxygen isotope analysis of the Czech cemeteries of Radovesice and Kutná Hora in Bohemia

Strontium and oxygen isotope analysis of human remains from the early La Tene (fourth/third century BC) Czech cemeteries of Radovesice I (RAD I), Radovesice II (RAD II), and Kutna Hora were conducted to investigate the importance of residential changes during the period of the historic “Celtic migrations”. In the initial phases (LT A/B), the grave goods of these cemeteries are typical for the core area of the La Tene culture, while around 300 BC (LT B2) an alteration occurs and typical Bohemian styles arise, and connections to Moravia and the Danubian region become visible. The strontium isotope ratios are highly varied with 87Sr/86Sr values between 0.7062 and 0.7153 in Radovesice, and betw…

research product

Evidence for “Celtic migrations”? Strontium isotope analysis at the early La Tène (LT B) cemeteries of Nebringen (Germany) and Monte Bibele (Italy)

Abstract Strontium isotope analysis on human remains from the Iron Age (4th/3rd century BC) cemeteries of Nebringen, Germany and Monte Bibele, Italy were carried out to investigate the role of residential changes during the period of the historic “Celtic migrations”. From an archaeological perspective, the location of the cemeteries in the Celtic core (Nebringen) and expansion area (Monte Bibele), and the distinctive development of their material culture, suggest that the buried populations had differing mobility rates. On the contrary, the strontium results indicate that only few individuals were mobile or non-local. There is, however, a difference in variation of strontium isotope ratios …

research product