Determining the palaeodrainage history of the Nile River: investigating rift tectonics and land-ocean-atmosphere interactions.

目的：该项目的目的是确定尼罗河的起源时间和古排水历史。尽管未公布的石油公司数据显示尼罗河三角洲的沉积物可追溯到渐新世，但关于这些沉积物的来源仍存在争议。许多研究人员认为，这些更古老的沉积物在当地来源于红海山，而一个广泛的尼罗河排水网络的开始，一直向南延伸到埃塞俄比亚和乌干达，直到后来才开始，估计范围从中新世到第四纪。研究的环境和经济影响：确定尼罗河的古水系对于更好地理解陆地-海洋-大气的相互作用至关重要，因为河流的水文直接受到大规模海洋和气候变化的影响。此外，这条河的排水有可能区分出与裂谷有关的隆起的羽流控制和均衡控制，而且它的排水也被认为影响了人类的扩散和古代文明。在经济上，该研究将有助于更好地了解大河如何影响海洋缺氧的发展和重要的烃源岩-岩浆岩的发展。具体到尼罗河三角洲的油气潜力，对岩心成分变化的记录可以评估：1)孔隙度/渗透率变化的时间变异性，从而预测油气远景；2)与沉积物分布相关的空间变异性，从而影响储层系统的井对比和分布。方法：来自新元古代红海山岛弧岩石的尼罗河三角洲沉积物与来自渐新世埃塞俄比亚洪水玄武岩（由青尼罗河排出）和太古宙-新元古代撒哈拉克拉通（由白尼罗河排出）的尼罗河源头的沉积物具有不同的岩石学、同位素和地球化学特征。从白尼罗河、青尼罗河和汇入红海山的河流中收集的现代河流沉积物将采用岩石学、同位素和地球化学技术（见表1；支持的理由）来描述这些潜在源区的特征。然后将数据与对始新世至近代尼罗河三角洲岩心样本的分析进行比较，并确定碎屑的来源。因此，从尼罗河源头开始向三角洲输入的时间可以推断出来，并记录了输入的变化随时间的变化。这些数据将与地下井和地震数据相结合，以产生沉积物输入和分布的区域时空理解。培训：学生将接受以下培训：1)地下数据分析，岩心描述，解释和采样；2)地球化学，同位素和岩石学技术；3)现代河流沉积物收集中的现场采样技术；4)通用的“可转移”技能。培训细节在单独的部分提供。学生将由经验丰富的主管和分析师进行培训。首席主管Najman（兰开斯特）在综合和解释多种技术的物源研究方面有20多年的经验。联合主管Butterworth （BP埃及）和Kneller（阿伯丁）都有超过20年的地下数据和深水系统工作经验，包括尼罗河三角洲。将进行同位素分析的NIGL是一个重视培训的世界级研究机构。在曼彻斯特和爱丁堡，地球化学分析将进行，提供由专门的实验室管理人员管理的最先进的设施。岩石学将在Garzanti（米兰-比可卡大学）的指导下进行，他在研究尼罗河和红海丘陵的河流的沙子方面有丰富的经验。

Aim: The aim of the project is to determine the time of initiation, and paleodrainage history, of the Nile River. Although unpublished oil company data show Nile delta sediments as old as Oligocene, debate exists as to the source of such sediment. Many workers consider that these older deposits are locally derived from the Red Sea Hills, and that initiation of an extensive Nile drainage network, extending as far south as Ethiopia and Uganda, did not occur until later, with estimates ranging from Miocene to Quaternary. Environmental and economic impact of the research: Determination of the Nile's palaeodrainage is critical to better understanding of land-ocean-atmosphere interactions since the river's hydrology is directly forced by large-scale oceanographic and climatic changes. Additionally, the river's drainage has the potential to allow discrimination between plume versus isostatic control on rift-related uplift, and its drainage is also thought to have influenced hominid dispersal and ancient civilisations. Economically, the study will contribute to a better understanding of how large rivers influence the development of ocean anoxia and development of sapropels which are important oil source rocks. Specific to Nile delta hydrocarbon potential, documentation of variation in the core's composition allows evaluation of 1) temporal variability of resultant changes in porosity/permeability and hence hydrocarbon prospectivity, 2) spatial variability, related to sediment distribution, with implications for well correlation and distribution of reservoir systems. Approach: Nile delta sediments locally sourced from the Neoproterozoic Red Sea Hills island arc rocks have a different petrographic, isotopic and geochemical signature from those derived from the Nile's headwaters of the Oligocene Ethiopian Flood Basalts (drained by the Blue Nile) and Archaean-Neoproterozoic Saharan Craton (drained by the White Nile). Modern river sediment collected from the White Nile, Blue Nile and rivers draining the Red Sea Hills will be subject to petrographic, isotopic and geochemical techniques (see Table 1; Case for Support) to characterise the signature of these potential source regions. Data will then be compared with analyses conducted on Nile delta core samples of Eocene to Recent age and the provenance of the detritus determined. Thus the time of initiation of input to the delta from the sources which are today at the Nile's headwaters can be deduced, and changes in input documented through time. These data will be coupled with subsurface well and seismic data to produce a regional temporal and spatial understanding of sediment input and distribution. Training: The student will be trained in 1) subsurface data analysis, and core description, interpretation and sampling, 2) geochemical, isotopic and petrographic techniques, 3) field sampling techniques during modern river sediment collection and 4) generic 'transferable' skills. Training details are provided in a separate section. The student will be trained by experienced supervisors and analysts. Lead supervisor Najman (Lancaster) has more than 20 years experience in the integration and interpretation of multi-technique provenance studies. Co-supervisors Butterworth (BP Egypt) and Kneller (Aberdeen) both have more than 20 years experience working on subsurface data and deepwater systems including the Nile delta. NIGL, where the isotopic analyses will be undertaken, is a world class research institute with emphasis on training. Manchester and Edinburgh, where geochemical analyses will be undertaken, provides state of the art facilities run by dedicated lab managers. Petrography will be carried out under the guidance of Garzanti (University of Milano-Bicocca) who has substantial experience in the study of sands from the Nile River and from rivers draining the Red Sea Hills.