Controls on sedimentary architecture of basin margins

盆地边缘沉积构造的控制

• 批准号: 6088-2009
• 负责人: Hiscott, Richard
• 金额: $ 2.94万
• 依托单位: Memorial University of Newfoundland
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2012
• 资助国家: 加拿大
• 起止时间: 2012-01-01 至 2013-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=513226
• 关键词: Controls; sedimentary; architecture; basin; margins

Earth history is recorded in sedimentary basins where detritus from surrounding lands accumulates along with particulate organic matter and biological remains that may later be transformed into oil, natural gas, or coal. The margins of basins are transitional areas where accumulation of detritus is regulated by fluctuating sea levels, wave and current erosion, and downslope transport of suspended sediment by gravity-driven density underflows called "turbidity currents". The small seas of western Turkey (Black Sea, Marmara Sea, Aegean Sea) provide unparalleled opportunities to study geological processes important to the evolution of ALL sedimentary basins. Periods of isolation of low-salinity water bodies from the global ocean, then reconnection, have generated strong chemical and biological signals in the sedimentary record that can be used to understand geological processes. Hiscott and collaborator Aksu have collected >100 sediment cores totaling >400 m in combined length in this region - several cores will be used for new graduate-student projects. A key part of the 2009-2014 research is monitoring of a unique saline underflow formed by dense Mediterranean water as it crosses the SW shelf of the low-salinity Black Sea. This is the only place on Earth where a density underflow with properties similar to deep-sea turbidity currents is assessible for monitoring in water depths <100 m. Key questions relate to the velocity structure of such currents and their interaction with bends of sinuous channels so common in the deep sea. The associated channel network was mapped in 2005 & 2008; a sophisticated program of monitoring and seabed sampling will be undertaken in 2010 & 2011 with British collaborators using the UK autonomous submersible AutoSub3. Other work in the region will address questions of organic-matter deposition, sources of sediment in the saline-channel banks and bars, and timing of major floodwater events in the last 15,000 years as the climate of central Asia shifted from a glacial to interglacial mode. Two current PhD students and four new students will receive training in multiple aspects of marine geoscience - several will participate in research cruises and learn practical sampling and surveying methods.

地球的历史记录在沉积盆地中，来自周围陆地的碎屑沿着与颗粒有机物和生物遗骸一起积累，这些物质后来可能转化为石油，天然气或煤炭。盆地的边缘是过渡区，碎屑的积累受到海平面波动、波浪和水流侵蚀以及被称为“浊流”的重力驱动的密度底流引起的悬浮沉积物的下坡输运的调节。土耳其西部的小海（黑海、马尔马拉海、爱琴海）为研究对所有沉积盆地的演变都很重要的地质过程提供了无与伦比的机会。低盐度水体与全球海洋隔离的时期，然后重新连接，在沉积记录中产生了强烈的化学和生物信号，可用于了解地质过程。Hiscott和合作者阿克苏在该地区收集了超过100个沉积物岩心，总长度超过400米-其中几个岩心将用于新的研究生项目。2009-2014年研究的一个关键部分是监测一个独特的盐水底流，该底流是由密集的地中海水穿过低盐度黑海的西南陆架形成的。这是地球上唯一一个可以在水深<100米的地方进行监测的地方，其密度底流具有类似于深海浊流的特性。关键问题涉及这种海流的速度结构及其与深海中常见的弯曲水道的相互作用。2005年和2008年绘制了相关的航道网络图; 2010年和2011年将与英国合作者利用英国自动潜水器AutoSub 3开展一项复杂的监测和海底取样方案。该地区的其他工作将解决有机物沉积、盐槽河岸和沙洲沉积物来源以及过去15，000年来中亚气候从冰期向间冰期转变时重大洪水事件的时间等问题。模式。两名现任博士生和四名新生将接受海洋地球科学多方面的培训-其中几名将参加研究巡航并学习实用的采样和测量方法。