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，已经钻了带有插图的Tephra层的沉积物，并采样到达Campanian。钻头位于印度洋Sunda弧线的火山阵线以西约800公里。巡航的目标是确定引起地震源性滑移的物质特性，并重建和理解印度季风循环的变化。在这个项目中，我们旨在通过将不同地点之间的广泛的tephra层与地面喷发相关联，以建立整个地区的海洋tephrospraphicraphic框架。因此，我们将将探险队的Tephra记录与整个印度洋以前的ODP钻探的海洋Tephra层相结合，尤其是在九十山脊上。用于tephra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出处和喷发继承。此外，我们将进行绝对年龄的日期，以改善和确认现有的年龄模型。需要健壮的年龄模型来研究喷发过程的时间和空间变化，Sunda Arc的大型火山喷发的大小和频率，或迄今为止未知的火山源。这项研究将有助于更多地了解有关不同火山系统的时间演化，并在该地区建立了长时间的爆炸性火山主义。在我们的记录中，我们将确定大型，但以前未知的喷发，这将使我们能够研究苏门答腊弧的更新世火山中心的复发率，并详细介绍Tephra记录中的循环。最后，我们还将研究尼科巴风扇的中新世至更新世沉积物记录，以检测隐藏在背景沉积中的增强的火山或单个事件的潜在发作。特别是确定在沉积物中纳入的火山物质的数量和特征对于表征材料及其作用的表征很重要，当它在地震生成和海藻发育性苏门答腊融合缘以俯冲时。