Establishing a new and detailed mid-Cretaceous palaeoceanographic record for the SE Pacific domain from Peru - Phase 2

我们对东太平洋地区白垩纪中期(阿普提安至图罗尼亚)古海洋学的了解严重受阻于从OPD和IODP岩心材料中恢复的远洋层序很差，以及陆上研究的数量有限。目前，仅有数量非常有限的墨西哥和哥伦比亚的研究存在。因此，关于东南太平洋白垩纪中期缺氧事件(OAE)影响的严格限制的数据极其罕见，这一特征突出了大西洋和特提斯案例研究的不成比例的区域偏见。由于秘鲁博士生胡安·巴勃罗·纳瓦罗·拉米雷斯先生获得DAAD奖学金3.5年，以及DFG的慷慨支持(建议BO 3655/2)，我们已经能够进行第一阶段的野外工作，并编制了卡哈马卡地区最新的阿普提安-图罗尼亚段的合成化学地层剖面。我们已经清楚地证明，秘鲁的野外工作是可以实现的，而且大量的泥晶碳同位素剖面具有欧洲和其他地方研究得很好的区段的特征。在此，我们申请DFG(本项目第二阶段)的新一轮支持，计划持续27个月。我们想进行第二个实地工作阶段，目的是评估秘鲁南美洲广阔的浅海陆架碳同位素特征的空间差异，从而评估当地的碳信号。它还旨在了解区域与全球营养水平变化在秘鲁有机物质生产和保存中的作用。

Our understanding of the mid-Cretaceous (Aptian to Turonian) paleoceanography of the east Pacific realm is severely hampered by the poor recovery of pelagic sequences from OPD and IODP core material and a limited number of land-based studies. At present, only a very limited number of studies from for example Mexico and Columbia exist. Therefore, well-constrained data on the impact of mid-Cretaceous anoxic events (OAE) in the SE Pacific are extremely rare, a feature that highlights the disproportional regional bias of Atlantic and Tethyan case studies. As a result of a DAAD scholarship obtained by the Peruvian PhD student Mr. Juan Pablo Navarro Ramirez for 3.5 years, and thanks to the generous support of the DFG (proposal BO 3655/2), we have been able to perform a first phase of fieldwork and compile a synthetic chemostratigraphic sections spanning the latest Aptian - Turonian interval in the Cajamarca region. We have clearly documented that fieldwork in Peru is achievable and that bulk micrite carbon isotope sections bear the characteristics of well-studied intervals in Europe and elsewhere. Here, we apply for a renewed support of the DFG (phase 2 of this project), scheduled to last 27 months. We would like to perform a second fieldwork phase that aims at assessing the spatial differences in the carbon isotope signature, and hence local carbon signals, of the vast epeiric neritic shelf of South America in Peru. It also aims at understanding the role of regional vs. global nutrient level changes in the production and preservation of organic matter in Peru.