Eruptive recurrence and magma accumulation for Quaternary stratovolcanoes in Central Anatolia

Erciyes Dagi和Hasan Dagi是中安纳托利亚最大的两座层状火山。这两座火山都被认为是活跃的，仅Erciyes Dagi附近就有100多万人居住。这一评估在很大程度上是基于土耳其对人类存在的独特而持久的考古记录，该记录初步证明了Erciyes Dagi和Hasan Dagi从史前到历史时代的同时代火山喷发。然而，这两座火山的喷发年龄都没有得到很好的量化，因此它们对过去文化演变和现代社会潜在威胁的影响仍然微乎其微。本文旨在研究额尔次耶斯达吉和哈桑达吉晚更新世至全新世火山活动的时间和岩浆作用过程。对于两座火山的最新矿床，将对副矿物锆石进行铀系不平衡和(U-Th)/He测年，以准确地约束喷发复发。为了更好地了解支撑这两座火山的岩浆系统的长期演化，将使用铀系锆石结晶年龄以及锆石的化学和同位素组成。锆石是唯一一种惰性的，不会扩散地质年代学和地球化学学上重要的微量元素，因此它可以记录绝对和长期时间尺度上岩浆的热和成分演化的时间。这超越了传统的火山岩分析，后者只能瞬时观察喷发前岩浆的物理和化学状态。由于锆石在岩浆中结晶的温度依赖性，锆石非常适合用来量化岩浆堆积和冷却的速度。通过对两座相邻火山的比较研究，可以测试有关外生过程的重要性的模型，如冰川-消融循环对火山喷发频率的影响。总的来说，这些数据对于重新评估东地中海和黑海地区的第四纪Tephra记录至关重要，对气候和考古档案的年代测定以及对该地区火山灾害的评估都有影响。这项建议的更广泛影响是与土耳其科学家进一步开展关于安纳托利亚中部火山的合作研究，促进学生和研究人员的国际交流，并提高公众对位于欧亚十字路口的重要地区火山危害的认识。

Erciyes Dagi and Hasan Dagi are the two largest stratovolcanoes in Central Anatolia. Both volcanoes are considered active, with more than 1 Million people residing in close proximity to Erciyes Dagi alone. This assessment is largely based on Turkey's uniquely protracted archaeological record of human presence which yielded tentative evidence for coeval volcanic eruptions of Erciyes Dagi and Hasan Dagi from prehistoric to historic times. Eruption ages of both volcanoes, however, are poorly quantified, and their impacts on past cultural evolution and potential threats for modern society therefore remain tenuous. This proposal is to study the timing and underlying magmatic processes of late Pleistocene to Holocene volcanism of Erciyes Dagi and Hasan Dagi. For the most recent deposits of both volcanoes, combined uranium series disequilibrium and (U-Th)/He dating will be applied to the accessory mineral zircon to accurately constrain eruptive recurrence. To better understand the long-term evolution of the magmatic systems underpinning both volcanoes, uranium series zircon crystallization ages, as well as the chemical and isotopic composition of zircon will be used. Zircon is uniquely inert against diffusion of geochronologically and geochemically important trace elements so that it can record the timing of the thermal and compositional evolution of magmas at absolute and protracted timescales. This transcends conventional analysis of volcanic rocks, which can only yield an instantaneous view into the physical and chemical state of magma immediately before eruption. Because of the temperature dependence of zircon crystallization in magmas, zircon is ideally suited to quantify rates of magma accumulation and cooling. The comparative investigation of two neighboring volcanoes allows testing of models regarding the importance of exogenic processes such as glaciation-deglaciation cycling on the frequency of volcanic eruptions. Collectively, these data are critical for the re-evaluation of Quaternary tephra records in the Eastern Mediterranean and Black Sea regions, with implications for dating of climate and archaeological archives and the assessments of volcanic hazards in this region. Broader impacts of this proposal are to further develop collaborative research on volcanoes in Central Anatolia with Turkish scientists, to promote international exchange of students and researchers, and to raise public awareness for volcanic hazards in an important region at the crossroads between Europe and Asia.