Physical properties, in situ structure and cyclicity of 1300 m Early Jurassic mudstones from geophysical logs in the ICDP Mochras borehole, West Wales

西威尔士 ICDP Mochras 钻孔地球物理测井中 1300 m 早侏罗世泥岩的物理性质、原位结构和循环性

• 批准号: 398741931
• 负责人: Dr. Christian Zeeden, since 4/2023
• 金额: --
• 依托单位: Leibniz-Institut für Angewandte Geophysik (LIAG)
• 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 2023-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/398741931?language=en
• 关键词: Physical; properties; situ; structure; cyclicity

The JET project is a large-scale, multi-faceted, international programme of research with about 50 project partners from 13 countries on the functioning of the Earth system at a key juncture in its history – the Early Jurassic – when it was subject to distinctive tectonic, magmatic, and orbital forcing, and fundamental aspects of the modern biosphere were becoming established in the aftermath of the end Permian and end Triassic mass extinctions. It is planned drilling a 1.9-km-deep borehole at Mochras, West Wales, to recover a 1.3-km-long core representing 27 Ma of Early Jurassic time. The overarching goal of the JET project is to generate a unique Early Jurassic record allowing investigation of the Earth system at a scale and resolution hitherto only attempted for the Cenozoic (i.e. archive sedimentation rate = 5 cm/ka or 20 a/mm), and to use that unique record together with existing data and an integrative modelling approach to produce a step-change in understanding of Early Jurassic Earth system dynamics.Our interpretation of (a) downhole logging data, (b) some additionally acquired physical properties on selected core plugs and (c) seismic reflection data will focus on the following objectives:• the characterisation of the lithology of the sediments including the detection of unconformities and lithological boundaries,• the determination of the paleoclimatic and paleoenvironmental history of this area,• the description of sediment facies and sedimentary cycles; compaction,• the improvement in knowledge about neotectonics and contemporary tectonics,• the integration and calibration of seismic reflection profiles and 3D modelling around the boreholes,• the calibration of sediment core logging properties to the ‘true depths’ of features in the borehole,• to maximize stratigraphic recovery in the most cost-effective manner.

JET项目是一个大规模、多方面的国际研究方案，有来自13个国家的约50个项目合作伙伴，研究地球系统在其历史上的一个关键时刻-早侏罗世-的运作，当时地球系统受到独特的构造、岩浆和轨道作用力，在二叠纪末和三叠纪末的大规模灭绝之后，现代生物圈的基本方面开始建立起来。计划在西威尔士的Mochras钻一个1.9公里深的钻孔，以恢复一个1.3公里长的岩心，代表早侏罗世27 Ma的时间。JET项目的首要目标是生成一个独特的早侏罗世记录，从而能够以迄今为止仅尝试用于新生代的规模和分辨率对地球系统进行调查（即档案沉降速率= 5 cm/ka或20 a/mm），并利用这一独特的记录，结合现有数据和综合建模方法，我们对（a）井下测井数据、（B）在选定的岩心塞上额外获得的一些物理性质和（c）地震反射数据的解释将集中于以下目标：·沉积物岩性的表征，包括不整合面和岩性边界的检测，·确定该地区的古气候和古环境历史，·描述沉积相和沉积旋回;压实，·关于新构造和当代构造的知识的改进，·地震反射剖面和钻孔周围的3D建模的集成和校准，·将沉积物岩心测井特性校准到钻孔中特征的“真实深度”，·以最具成本效益的方式最大化地层恢复。