Tephrochronology of lacustrine ash layers in Lake Petén Itzá sediments: Implications for regional volcanology and Central American palaeoclimate

对危地马拉Petén Itzá湖深钻计划沉积物的拟议研究结合了火山学、古气候学、古生态学等领域，以建立中美洲最长的气候代用品古记录，并延续火山灰记录超过200 ka。基于主要元素指纹的Petén Itzá灰烬的初步年代学将通过微量元素相关性得到加强。此外，与中美洲火山前缘喷发的相关性将大大有助于确定这些喷发的规模，因为特别是喷发沉积物的远端部分保留了更好地限制喷发量的关键。湖相火山熔岩的直接年龄测定，以及整个地区的主要关键层Los Chocoyos火山熔岩的年龄测定，将进一步帮助和校准由此产生的年龄模型。该建议的另一个方面是将海洋和湖泊火山灰地层学联系起来，因此也将大型大陆和海洋钻井计划联系起来，其中与中美洲的野外火山灰的相关性超出了已知的火山弧火山灰继承。

The proposed research on sediments from the deep drilling program at lake Petén Itzá, Guatemala, combines the fields of volcanology, paleoclimate, paleoecology, in order to establish the longest paleo-record for climate proxies in Central America as well as a continuation of the tephra record beyond 200 ka. Preliminary tephrachronology of the Petén Itzá ashes based on major element fingerprinting will be strengthend by trace lement correlations. Additionally the correlations to eruptions of the Central American volcanic front will contribute greatly to the determination of the magnitude of those eruptions since especially the distal part of the eruption deposits preserves the key to better constraint eruptive volumes. Direct age dating of lacustrine tephras but also the Los Chocoyos tephra, a major key bed in the entire region, will further assist and calibrate the resulting age model. Another aspect of the proposal is to link marine and lacustrine tephrostratigraphy, and therefore also the large continental and marine drilling programs, where the correlation to field tephras from Central America is beyond the known well-constrained tephra succession from the volcanic arc.