Assessing the sediment factory: The role of single grain analysis
Assessing the sediment factory: The role of single grain analysis
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DOI：
10.1016/j.earscirev.2012.08.001
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发表时间：
2012-10
影响因子：
12.1
通讯作者：
H. Eynatten;I. Dunkl
中科院分区：
文献类型：
--
作者：
H. Eynatten;I. Dunkl
沉积物生成的类型和数量与当今地球表面以及整个地质历史中活跃的构造和气候过程密切相关。来自年代确定的沉积地层的碎屑单颗粒（砂至非常粗的粉砂大小）可作为沉积系统中的矿物示踪剂，并记录沉积物形成过程。在这篇评论中，选择的个别方法可提取岩石和年代学信息的碎屑矿物颗粒的汇编。重点放在技术，概念，和他们的可能性和缺点，在定义类型和地质历史的源岩，以及沉积物被侵蚀和交付盆地的速度和相对比例。统计问题本质上耦合到解释的碎屑单颗粒分布的突出，以及新兴的技术。这些方法包括对例如钛铁矿、独居石或金红石等相的地质年代学，以克服对磷灰石或锆石的常见限制，以及任何类型的双重或三重定年，以从相同的碎屑颗粒中提取高温和低温热年代学信息。矿物对特别适合于量化定义明确的源岩或区域对沉积物的相对贡献，当这两个阶段（i）发生在对比的岩石类型中，（ii）在沉积条件下相对稳定，（iii）允许提取源岩岩石学和年代学的重要和详细信息。然而，一般来说，多方法的方法是唯一的方法来克服模糊的信息从沉积记录。结合来自单颗粒热年代学的关于沉积通量或侵蚀速率的独立信息，可以适当地评估沉积物形成过程及其控制机制和总体地质背景。
Type and amount of sediment generation are intimately connected to tectonic and climatic processes active at the earth's surface today as well as throughout the geologic past. Detrital single grains (sand to very coarse silt sized) from well-dated sedimentary formations serve as mineral tracers in sedimentary systems and record the sediment-forming processes. In this review, a selection of individual methods available to extract petrogenetic and chronological information from detrital mineral grains is compiled. Emphasis is placed on techniques, concepts, and their possibilities and shortcomings in defining the type and geologic history of source rocks, as well as the rates and relative proportions at which sediments are being eroded and delivered to basins. Statistical issues intrinsically coupled to the interpretation of detrital single-grain distributions are highlighted, as well as new emerging techniques. These include geochronology of phases like e.g. titanite, monazite, or rutile to overcome the common restriction to apatite or zircon bearing lithologies, as well as any kind of double or triple dating to extract both high-T and low-T thermochronological information from the very same detrital grains. Mineral pairs are especially suited to quantify the relative contributions of well-defined source rocks or areas to the sediment when the two phases (i) occur in contrasting rock types, (ii) are relatively stable under sedimentary conditions, and (iii) allow for extracting significant and detailed information on source rock petrology and chronology. In general, however, multi-method approaches are the only way to overcome ambiguous information from the sedimentary record. In combination with either independent information on sediment flux or erosion rates derived from single-grain thermochronology, the sediment-forming processes as well as their controlling mechanisms and overall geologic settings can be properly assessed.