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考察期间，对具有火山灰夹层的沉积物进行了钻探和取样，这些沉积物一直延伸到坎帕阶。钻探地点位于印度洋巽他弧火山前缘以西约800公里处。考察的目的是确定引起地震滑动的物质特性，并重建和了解印度季风环流的变化。在这个项目中，我们的目标是建立一个海洋火山灰地层框架，整个地区的相关广泛火山灰层之间的不同网站，如果可能的话，陆地喷发。因此，我们将联合收割机的火山碎屑记录与海洋火山碎屑层从以前的ODP钻探从整个印度洋，特别是在Ninetyeast海岭。火山灰和沉积物特征的地球化学，岩石学和火山学方法将用于定量和定性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弧或迄今为止未知的火山源的大型火山喷发过程、震级和频率的时空变化。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作用的长时间序列。在我们的记录中，我们将确定大的，已知的，但也是以前未知的，喷发，这将使我们能够研究各自的复发率从更新世火山中心的苏门答腊弧，并详细说明火山灰记录的周期性。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。特别是确定火山物质的数量和性质，这是纳入沉积物是重要的，以表征材料和它是如何行动的，当它是俯冲在地震和海啸的苏门答腊收敛边缘。