Regional Paleosol Variability on a Dissected Alluvial/Coastal Plain: A Proposal to Develop an Empirical Paleosol-Landscape Model for Nonmarine Sequence Stratigraphy

解剖冲积/沿海平原的区域古土壤变化：开发非海洋层序地层经验古土壤景观模型的建议

• 批准号: 0229196
• 负责人: Paul McCarthy
• 金额: $ 11.58万
• 依托单位: University of Alaska Fairbanks Campus
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-01-01 至 2005-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0229196&HistoricalAwards=false
• 关键词: Regional; Paleosol; Variability; Dissected; Alluvial

Regional Paleosol Variability on a Dissected Alluvial/Coastal Plain:A Proposal to Develop an Empirical Paleosol-Landscape ModelFor Nonmarine Sequence Stratigraphy and Terrestrial Basin AnalysisPaul McCarthyEAR-0229196 The use of paleosols (fossil soils) for partitioning continental rocks and understanding changing sedimentation rates in terrestrial sedimentary basins is now firmly established. Early successes in applying paleopedological techniques to the recognition and correlation of terrestrial unconformities (sequence boundaries) have built largely upon paleosol-landscape models that were developed primarily from aggradational basin settings. In contrast, relatively little attention has been paid to paleosol variability in an alluvial/coastal plain undergoing dissection during the falling stage on the relative sea level curve. This research will document the spatial variability of paleosols across a single interfluve surface in the Cretaceous (Cenomanian) Dunvegan Fm. with respect to distance from associated valley margins and the coeval paleo-shoreline. The Dunvegan Fm. is ideally suited for this study because it is both spatially extensive and stratigraphically well understood; because coeval shallow marine and shoreline environments can be confidently correlated with nonmarine deposits updip; and because paleo-valley deposits have been mapped in detail and the distance from any interfluve paleosol to the valley margin can be fairly accurately determined. Ten paleosols will be sampled from a single interfluve at distances from less than 1 km to more than 20 km from adjacent valley margins along a transect extending more than 250 km updip from the coeval shoreline. Paleosols will be described in the field and analyzed for micromorphological features, geochemistry and mineralogy. Micromorphological features will be quantified and paleosols will be objectively compared using a soil micromorphology index. These paleopedological data will be used to reconstruct the pedosedimentary histories of these paleosols, to develop a paleosol-landscape model for dissected alluvial/coastal plain settings, and to assess the value of the soil micromorphology index for objective description and comparison of paleosols both within and between basins.

区域古土壤变异性的一个解剖冲积/沿海平原：一个建议，以发展一个经验性的古土壤景观模型为Nonmarine层序地层学和陆地盆地analysisPaul麦卡锡-0229196使用古土壤（化石土壤）划分大陆岩石和了解变化的沉积速率在陆地沉积盆地现在已经牢固确立。 应用古土壤学技术识别和对比陆地不整合面（层序边界）的早期成功主要建立在古土壤景观模型上，这些模型主要是从加积盆地环境中开发的。 相比之下，相对较少的关注已经支付给古土壤的变化，在相对海平面曲线的下降阶段，在一个冲积/沿海平原进行解剖。这项研究将记录在白垩纪（Cenomanian）Dunvegan组的古土壤在一个单一的河间表面的空间变异性。相对于相关的山谷边缘和同时代的古海岸线的距离。 Dunvegan FM。非常适合这项研究，因为它是空间上的广泛和地层上的理解，因为同时代的浅海和海岸线环境可以确信相关的非海洋沉积物上倾，因为古河谷沉积物已详细绘制，从任何河流间古土壤到山谷边缘的距离可以相当准确地确定。 从同一时期海岸线上倾超过250 km的一个断面上，沿沿着距离相邻谷缘不到1 km至20 km的单一河间带采集10种古土壤样本。 古土壤将在野外进行描述，并进行微形态特征、地球化学和矿物学分析。 微形态特征将被量化，古土壤将使用土壤微形态指数进行客观比较。 这些古土壤学数据将被用来重建这些古土壤的土壤沉积历史，开发一个古土壤景观模型解剖冲积/沿海平原设置，并评估客观的描述和比较古土壤的土壤微形态指数的价值和盆地之间。