Origin, petrogenesis and geodynamic implications of the early Eocene Altınpınar adakitic andesites in the eastern Sakarya Zone, northeastern Turkey

The Sr, Nd, Pb and Hf isotopes and crystallization conditions of the middle Eocene Dağdibi Pluton in the eastern Sakarya Zone, Turkey

“…(Kandemir et al 2019). Adakite-like rocks are the first igneous products of this syn- to post-collisional period (Dokuz et al 2013, 2019; Gücer, 2021). They intruded into the crust in the early Eocene (55–50 Ma) following a magmatic lull up to 10 to 12 Ma after the final subduction-related products at around 72 Ma (Topuz et al 2005; Eyüboğlu et al 2011; Karslı et al 2011).…”

“…Arslan et al 2013; Temizel et al 2016) and slab break-off (e.g. Keskin et al 2008; Dilek et al 2010; Altunkaynak et al 2012; Dokuz et al 2019; Gücer, 2021). The authors consider that the slab-breakoff model best explains the Early Cenozoic post-collisional magmatism in the Sakarya Zone as outlined in Dokuz et al (2019).…”

“…The Dağdibi Pluton is located in the eastern part of the Sakarya Zone, Turkey, a crustal segment lying in the middle parts of the Alpine-Himalayan Orogenic Belt. Although the igneous rocks with ages varying from Carboniferous to Miocene are found in the eastern Sakarya Zone, those formed in the time interval from the Late Cretaceous to the end of Eocene are very common (Sipahi, 2005, 2017, 2019; Arslan & Aslan, 2006; Boztuğ et al 2007; Kaygusuz et al 2012, 2018, 2020; Temizel et al 2012; Aydınçakır, 2014; Sipahi & Sadıklar, 2014; Gücer et al 2017; Dokuz et al 2019; Sipahi et al 2020a, 2020b, 2022; Gücer, 2021). Particularly the eastern part of the Sakarya Zone is therefore regarded as a paleo-magmatic arc and a natural laboratory to study the tectonic and petrogenetic processes that occurred through the time interval from the final stages of subduction to post-collision.…”

“…1a), the cause of the Eocene magmatism is still not fully understood. Late Cretaceous subduction-related magmatism was followed, after a magmatic stagnation of ∼10–12 Ma, by a short-lived adakitic magmatism that occurred in a time span from 56 to 50 Ma with a peak at around 52–50 Ma (Karslı et al 2010; Eyüboğlu et al 2011; Dokuz et al 2013; Gücer, 2021) and then a non-adakitic magmatism varying in age from 50 to 38 Ma (Boztuğ et al 2004; Arslan & Aslan, 2006; Karslı et al 2012; Eyüboğlu et al 2017; Sipahi et al 2017; Kaygusuz et al 2018; Dokuz et al 2019; Sipahi et al 2022).…”

Grain size-dependent pollution levels in clastic sedimentary rocks, the example of the Eocene aged sequence (NE Türkiye)

“…To assess environmental pollution degrees are carried out many methods such as enrichment factor, geo-accumulation index, contamination index, ecological risk index, contamination degree index, and potential ecological risk index (Chester & Stoner, 1973;Müller, 1979Müller, , 1981Hakanson, 1980;Adeboya et al, 2022). The named indices assess the PTE concentrations and de ne whether heavy metals are anthropogenic origin, potential risk degrees, and likely impacts on human health Gücer, 2021). However, the level of potentially toxic elements in these sedimentary units has not been already evaluated, therefore, this research focused on assessing the accumulation of potentially toxic elements.…”