Climatic indications from soils and sands, and their lithified equivalents

沉积物是了解地球随时间和空间变化的气候条件的重要资源。具体的大气指标包括：1)土壤风化剖面；2)重矿物组（密度为> - 2.9的矿物）的分布；3)稳定的碎屑矿物（如石英）的比例；4)对风化高度敏感的铝硅酸盐（粘土矿物）。砂和砂岩特别适合于组分研究（即矿物和岩石碎片），而细粒度组分则可用于主要元素和微量元素地球化学以及稳定同位素分析。这项研究计划的目的是双重的，包括：1)确定在地球历史上特定时期控制沉积物形成和沉积的气候条件；2)研究现代环境中不同的气候条件如何控制沉积物组成。这个研究项目代表了项目和分析技术的整合，将有助于更清楚地了解地球的气候演变。建议进行以下项目：i)加拿大西部沉积盆地晚阿尔比世“正常”和“超级”古土壤的区分及其对气候条件和海侵的影响；ii)新西兰中奥塔哥地区晚白垩世-中新世气候变化的多重古土壤证据；iii)玄武岩上发育的现代含芯土剖面中微量元素的分布；气候对纳米比亚和新西兰现代干旱和温带冲积扇沉积物组成和质地的影响。样品将使用主要和微量元素地球化学和稳定同位素分析，扫描电子显微镜和阴极发光光谱分析。拟议的研究项目将资助两名博士生、两名硕士和一名博士后。这个研究项目意义重大，因为在地球演化过程中，影响沉积物组成的最重要的过程是气候，因为气候直接影响着地球上生物群的发展。

Sedimentary deposits are a significant resource for understanding Earth's changing climatic conditions through time and space. Specific atmospheric indicators are represented by 1) soil weathering profiles 2) the distribution of heavy mineral suites (minerals with densities >2.9), 3) proportions of stable detrital minerals, such as quartz, and 4) aluminosilicate (clay) minerals that are highly sensitive to weathering. Sands and sandstones are particularly favourable for componentry studies (i.e. minerals and rock fragments), whereas finer-grained fractions are useful for major and trace element geochemistry, and stable isotope analysis. The aim of this proposed research program is two-fold and involves, i) determining the climatic conditions that governed sediment formation and deposition at specific times in Earth history, and ii) examining how different climatic conditions in modern settings control sediment composition. This research program represents a consolidation of projects and analytical techniques that will contribute toward a clearer understanding of Earth's climatic evolution. The following projects are proposed: i) Distinguishing between Late Albian "normal" and "super" palesols in the Western Canada Sedimentary Basin, and their implications for climate conditions and marine transgression, ii) Climatic variations during the Late Cretaceous-Miocene Central Otago region, New Zealand as evidenced from multiple paleosols, iii) The distribution of trace elements in modern corestone-bearing soil profiles developed on basalt, and iv) The effects of climate on the composition and textures of modern arid and temperate alluvial fan deposits of Namibia and New Zealand. The samples will be analyzed using major and trace element geochemistry and stable isotope analysis, scanning electron microscopy, and cathodoluminescence spectroscopy. The proposed research program will fund two Ph.D. students, two M.Sc. students and one Post-doctoral Fellow. The research program is significant because the most important process governing sediment composition with respect to Earth's evolution is climate, as it directly affects the development of biota on our planet.