Traces of explosive eruptions in Cretaceous to Quaternary Indian Ocean sediments.

白垩纪至第四纪印度洋沉积物中爆​​炸性喷发的痕迹。

• 批准号: 407425515
• 负责人: Privatdozent Dr. Steffen Kutterolf
• 金额: --
• 依托单位: Forschungseinheit Magmatische und Hydrothermale Systeme
• 依托单位国家: 德国
• 项目类别: Infrastructure Priority Programmes
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/407425515?language=en
• 关键词: Traces; explosive; eruptions; Cretaceous; Quaternary

During IODP Expeditions sediments with intercalated tephra layers have been drilled and sampled that reach down to the Campanian. The drill sites are located ~800 km west of the volcanic front of the Sunda arc in the Indian Ocean. The objectives of the cruises were to determine the material properties causing the seismogenic slip and to reconstruct and understand changes in Indian monsoon circulation. In this project we aim to establish a marine tephrostratigraphic framework for the entire region by correlating widespread tephra layers between the different sites and if possible, to terrestrial eruptions. Therefore we will combine the tephra records of Expeditions with marine tephra layers from previous ODP drillings from the whole Indian Ocean, and on the Ninetyeast Ridge in particular. Geochemical, petrological and volcanological approaches for tephra and sediment characterization will be used to quantitatively and qualitatively decrypt their provenance and the eruption succession. Additionally, we will perform absolute age dating to improve and confirm the existing age models. Robust age models are needed to study the temporal and spatial changes in eruption processes, magnitudes and frequencies of large volcanic eruptions from the Sunda arc, or so far unknown volcanic sources.This study will help to learn more about the temporal evolution of different volcanic systems and establish long time series of explosive volcanism in this region. Within our record we will identify large, known, but also previously unknown, eruptions, which will enable us to study the respective recurrence rates from Pleistocene volcanic centres of the Sumatran arc and to elaborate on cyclicities in the tephra record. Finally, we will also study the Miocene to Pleistocene sediment record of the Nicobar Fan to detect potential episodes of enhanced volcanism or single events hidden in the background sedimentation. Especially the determination of the amount and character of volcanic matter that is incorporated in the sediments is important to characterize the material and how it acts, when it is subducted at the seismogenic and tsunamogenic Sumatran convergent margin.

在 IODP 探险期间，对带有夹层火山灰层的沉积物进行了钻探和取样，一直延伸到坎帕尼亚。钻探地点位于印度洋巽他岛弧火山前缘以西约 800 公里处。巡航的目的是确定导致地震滑移的物质特性，并重建和了解印度季风环流的变化。在这个项目中，我们的目标是通过将不同地点之间广泛分布的火山灰层（如果可能的话）与陆地喷发联系起来，为整个地区建立一个海洋火山地层框架。因此，我们将把探险队的火山灰记录与之前在整个印度洋（尤其是九十东海脊）进行的 ODP 钻探中的海洋火山灰层结合起来。用于火山灰和沉积物表征的地球化学、岩石学和火山学方法将用于定量和定性地解密其来源和喷发序列。此外，我们将进行绝对年龄测定，以改进和确认现有的年龄模型。需要稳健的年龄模型来研究巽他岛弧大型火山喷发或迄今为止未知的火山源的喷发过程、强度和频率的时空变化。这项研究将有助于更多地了解不同火山系统的时间演化并建立该地区爆发性火山活动的长期序列。在我们的记录中，我们将识别大型、已知但以前未知的喷发，这将使我们能够研究苏门答腊岛弧更新世火山中心各自的复发率，并详细说明火山灰记录中的周期性。最后，我们还将研究尼科巴扇的中新世至更新世沉积物记录，以检测潜在的增强火山活动或隐藏在背景沉积中的单一事件。尤其是确定沉积物中火山物质的数量和特征，对于表征该物质及其在地震和海啸苏门答腊汇聚边缘俯冲时的作用非常重要。