IODP Expedition 381 Corinth Rift: FEC Co-Chief Scientist Duties and Post-Moratorium Research

IODP 科林斯裂谷 381 号探险队：FEC 联合首席科学家职责和暂停后研究

• 批准号: NE/R016550/1
• 负责人: Lisa McNeill
• 金额: $ 12.9万
• 依托单位: University of Southampton
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2017
• 资助国家: 英国
• 起止时间: 2017 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FR016550%2F1
• 关键词: IODP; Expedition; 381; Corinth; Rift

The discovery of plate tectonics in the 1960's has provided geologists with insight into the causes of earthquakes and the continued re-organisation of the continents. An important part of plate tectonic theory is continental rifting and breakup, the process that begins the process of breaking apart a continent and ultimately can result in the formation of a new ocean. There are many continental margins on Earth where we know rifting has acted in the past and these margins are the source of much of the world's oil and gas resources, but there are limited places where we can witness the active processes that presently characterise the formation of a rift valley. Of the relatively small number of places on Earth where the process of continental rifting is just starting, the Gulf of Corinth, Greece stands out as a rare location of earthquake activity, high rates of the plate being split apart and a record of the rifting process contained in the sediments now filling the rift basin. Therefore it holds vital clues as to how a tectonic plate stretches and splits into two. The Corinth Rift has been studied for several decades, with scientists investigating its rift deposits and active fault traces exposed on land. But much of the activity is hidden below the inland sea of the Gulf of Corinth and in order to investigate this part of the rift, researchers have used marine geophysics to image the faults and sedimentary layers below the seafloor. They have also sampled the shallowest sediments using coring techniques. The has allowed us to see how faults have developed to create the basin and cause it to gradually subside as the rifting process evolves. We can also see how the sediment, eroded from the land surrounding the basin, has gradually filled the subsiding basin and records the movement of the faults through time. What has been lacking is direct sampling of these sediments over a significant part of the time since rifting began. This would enable us to determine how old the different sedimentary layers are and therefore how fast the faults are moving and how quickly the rift is opening and changing. Sampling and investigating the plants and animals living within and around the basin would also tell us the environment of the basin - was it a marine sea, a freshwater lake, or a series of river and delta systems and how has this changed as the rift has developped? These flora and fauna would also tell us about the local climate of this part of the Eastern Mediterranean and how this related to changes in the global climate in the last 1-2 million years, and how climate might have affected how and how much sediment was eroded and transported into the basin.The Integrated Ocean Discovery Program (IODP) will be drilling 3 boreholes in order to sample these rift basin sediments to answer the problems and questions raised above. This method, using a drillship, is the only way these sediments can be accessed. Approximately 32 scientists of a wide range of geoscience disciplines will analyse the cores and log data (which give information on the physical properties of the sediments) together over a period of 3 months offshore and onshore and then over a period of 3-4 years after the expedition. In addition, McNeill will take some of the drilling results and compare them with the already collected marine geophysical data to get a better idea of how fast faults are slipping, the basin is opening up, and how fast it has been subsiding, which can tell us how much the continental crust of the plate has thinned since the start of rifting. The results will be very relevant to understanding the potential for earthquake hazards in the region (how fast faults move is a major control on earthquake potential) and also to understanding how and where hydrocarbon resources collect within the earliest and deepest part of a rift system.

20世纪60年代板块构造的发现使地质学家们对地震的成因和大陆的持续重组有了深入的了解。板块构造理论的一个重要组成部分是大陆裂谷和分裂，这一过程开始了大陆分裂的过程，并最终导致新海洋的形成。地球上有许多大陆边缘，我们知道裂谷作用在过去发生过，这些边缘是世界上大部分石油和天然气资源的来源，但我们可以看到目前形成裂谷的活跃过程的地方有限。在地球上大陆裂谷过程刚刚开始的相对较少的地方中，希腊的科林斯湾是一个罕见的地震活动地点，板块分裂的速度很高，现在填充裂谷盆地的沉积物中包含了裂谷过程的记录。因此，它掌握了构造板块如何伸展并一分为二的重要线索。科林斯裂谷已经被研究了几十年，科学家们调查了它的裂谷沉积物和暴露在陆地上的活动断层痕迹。但是，大部分活动都隐藏在科林斯湾的内海下面，为了调查裂谷的这一部分，研究人员利用海洋地球物理学对海底以下的断层和沉积层进行了成像。他们还利用取芯技术对最浅的沉积物进行了取样。这使我们能够看到断层是如何发展形成盆地的，并随着裂谷过程的发展而逐渐消退。我们还可以看到沉积物是如何从盆地周围的土地上侵蚀出来的，逐渐填充了下沉的盆地，并记录了断层的运动。一直缺乏的是直接采样的这些沉积物在相当大的一部分时间以来裂谷开始。这将使我们能够确定不同沉积层的年龄，从而确定断层移动的速度以及裂谷打开和变化的速度。对生活在盆地内部和周围的植物和动物进行取样和调查也会告诉我们盆地的环境--它是海洋、淡水湖还是一系列的河流和三角洲系统，以及随着裂谷的发展，这些系统是如何变化的？这些植物群和动物群也会告诉我们东地中海这一部分的当地气候，以及这与过去1-2百万年全球气候变化的关系，以及气候可能如何影响沉积物被侵蚀和输送到盆地的方式和数量。综合海洋发现计划（IODP）将钻探3个钻孔，以便对这些裂谷盆地沉积物进行取样，以回答上述问题。这种使用钻探船的方法是获取这些沉积物的唯一途径。大约32名来自各种地球科学学科的科学家将在海上和陆上3个月的时间内，然后在考察后3-4年的时间内，共同分析岩心和测井数据（提供关于沉积物物理性质的信息）。此外，麦克尼尔还将获取一些钻探结果，并将其与已经收集到的海洋地球物理数据进行比较，以更好地了解断层滑动的速度、盆地张开的速度以及沉降的速度，这可以告诉我们自裂谷开始以来，板块的大陆地壳变薄了多少。研究结果将有助于了解该地区地震灾害的可能性（断层移动的速度是地震可能性的主要控制因素），也有助于了解油气资源如何以及在裂谷系统最早和最深的部分聚集。

项目成果

A new deglacial climate and sea-level record from 20 to 8 ka from IODP381 site M0080, Alkyonides Gulf, eastern Mediterranean

• DOI: 10.1016/j.quascirev.2023.108192
• 发表时间: 2023-08
• 期刊: Quaternary Science Reviews
• 影响因子: 4
• 作者: I. Mazzini;T. Cronin;R. Gawthorpe;R. E. Ll Collier;Gino de Gelder;A. Golub;M. Toomey;R. Poirier;Huai-Hsuan May Huang;M. P. Phillips;L. McNeill;D. Shillington

Author Correction: High-resolution record reveals climate-driven environmental and sedimentary changes in an active rift.

作者更正：高分辨率记录揭示了活跃裂谷中气候驱动的环境和沉积变化。

• DOI: 10.1038/s41598-019-42749-y
• 发表时间: 2019
• 期刊: Scientific reports
• 影响因子: 4.6
• 作者: McNeill LC

Corinth Active Rift Development

科林斯活动裂谷发育

• 发表时间: 2019
• 作者: McNeill LC

Preliminary results from IODP Expedition 381: Development of the active Corinth Rift, Greece

IODP 第 381 次探险的初步结果：活跃的希腊科林斯裂谷的发育

• 发表时间: 2018
• 作者: McNeill LC

Rift history, syn-rift sedimentation and paleoenvironment of the Corinth Rift basin: IODP Expedition 381 preliminary results

科林斯裂谷盆地的裂谷历史、同裂谷沉积和古环境：IODP Expedition 381 初步结果

• 发表时间: 2018
• 作者: McNeill LC