Sediment routing controls on CO2 mineralisation potential

沉积物路由对二氧化碳矿化潜力的控制

• 批准号: 2892630
• 金额: --
• 依托单位: Imperial College London
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2023
• 资助国家: 英国
• 起止时间: 2023 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2892630
• 关键词: Sediment; routing; controls; CO2; mineralisation

Geological storage of CO2 has the potential to decarbonise much energy production and heavy industry. The most secure mechanism for permanent trapping of CO2 is mineralisation. Its effectiveness depends on: (1) the reactivity of mineral grains to injected CO2, and (2) rock texture, which controls dispersal of injected CO2 and the grain surface area available for mineralisation. Saline aquifers are the most attractive targets for storing injected CO2 at industrial scale, but many saline aquifers lack data required to characterise their mineralisation potential.This project will use sediment routing concepts to develop a first-order predictive model of the mineralisation potential of sandstones, based on upstream-to-downstream trends in depositional grain size, sorting and mineralogical composition. These trends arise from selective deposition of coarse grain sizes and variations in the physico-chemical durability of different minerals during sediment transport. The grain sizes, sorting and mineralogy of sand deposited in different segments of a sediment routing system are primary controls on the sandstone textures and geochemical characteristics that develop during burial diagenesis, and thus on their mineralisation potential. The project will focus on feldspathic sandstones, which contain calcium- and potassium-rich feldspars that react with and trap injected CO2 by precipitation of carbonate and clay minerals. However, feldspar grains also break down more rapidly than quartz during transport - thus decreasing reactive mineral content and mineralisation potential.1) The project will characterise trends in grain size, sorting and mineralogy in a modern sediment routing system draining the feldspar-rich, granitic and gneissic Iberian Massif, Spain. The student will collect field data to develop a self-similarity-based depositional model for grain size, coupled to feldspar content evolution as a function of transport distance and climate.2) The resulting model will be tested and calibrated against an ancient sediment routing system with CO2 storage potential. The feldspathic Sherwood Sandstone records deposition in fluvial, aeolian and lacustrine segments of the "Budleighensis" sediment routing system, which spanned the Wessex, Worcester, Cheshire, East Irish Sea, Solway and Carlisle basins, UK. CO2 storage is planned or proposed in Sherwood Sandstone saline aquifers and/or depleted hydrocarbon reservoirs in these basins. Previous work implies that feldspar content in the sandstones decreases downsystem, from 20-50% in Wessex Basin to 5-8% in the Solway and Carlisle basins. The student will interpret seismic, well, core and outcrop data to document the sediment volumes, grain size characteristics and petrography of sandstones in the "Budleighensis" sediment routing system. Results will have specific applications to CO2 storage projects in the UK, and also to generic assessment of CO2 mineralisation potential in sedimentary basins globally.

二氧化碳的地质储存有可能使许多能源生产和重工业脱碳。永久捕获二氧化碳的最安全机制是矿化。其有效性取决于：（1）矿物颗粒对注入CO2的反应性，以及（2）岩石结构，其控制注入CO2的分散和可用于矿化的颗粒表面积。咸水层是工业规模储存注入CO2的最有吸引力的目标，但许多咸水层缺乏验证其矿化潜力所需的数据。该项目将使用沉积物路线概念，根据沉积物粒度、分选和矿物成分的上游至下游趋势，开发砂岩矿化潜力的一阶预测模型。这些趋势是由于粗粒度矿物的选择性沉积和沉积物搬运过程中不同矿物的物理化学耐久性的变化造成的。沉积物路径系统不同段中沉积的砂的粒度、分选和矿物学是埋藏成岩作用过程中形成的砂岩结构和地球化学特征的主要控制因素，从而控制其矿化潜力。该项目将侧重于富钙和富钾长石砂岩，这些砂岩与注入的二氧化碳发生反应，并通过碳酸盐和粘土矿物的沉淀而捕获二氧化碳。然而，长石颗粒在运输过程中也比石英更快地分解-从而降低了活性矿物含量和矿化潜力。1）该项目将在现代沉积物路由系统中揭示粒度、分选和矿物学的趋势，该系统将对西班牙伊比利亚地块富含长石、花岗岩和片麻状岩石进行排水。学生将收集现场数据，以开发基于自相似性的粒度沉积模型，并将长石含量演变作为运输距离和气候的函数。2）将根据具有CO2储存潜力的古代沉积物路由系统对所得模型进行测试和校准。“Budleighensis”沉积物路径系统的河流、风成和湖泊段沉积物中的灰岩型舍伍德砂岩记录，该沉积物路径系统横跨英国威塞克斯、伍斯特、柴郡、东爱尔兰海、索尔韦和卡莱尔盆地。在这些盆地的舍伍德砂岩含盐含水层和/或枯竭油气藏中计划或提议进行CO2储存。以前的研究表明，砂岩中长石的含量沿系统向下降低，从威塞克斯盆地的20-50%降低到索尔韦和卡莱尔盆地的5-8%。学生将解释地震，井，岩心和露头数据，以记录沉积物体积，粒度特征和砂岩的岩相学在“Budleighensis”沉积物路由系统。结果将有具体的应用，在英国的二氧化碳储存项目，也在全球沉积盆地的二氧化碳矿化潜力的一般评估。