当前位置: X-MOL 学术J. Sediment. Res. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Sequence stratigraphic interpretation in marginal marine settings by the approach of parasequence-thickness-to-sandstone-fraction ratio: Case studies of the Gallup and Ferron outcrops in the Western Interior Basin, U.S.A.
Journal of Sedimentary Research ( IF 2 ) Pub Date : 2022-02-28 , DOI: 10.2110/jsr.2021.011
Tuoyu Wu 1 , Janok P. Bhattacharya 1 , Logan Jung-Ritchie 1
Affiliation  

The parasequence-thickness-to-sandstone-fraction ratio (TSF) is a simple but potentially powerful tool to identify stratal stacking patterns and associated systems tracts in siliciclastic paralic sequences. Parasequence thickness (T) reflects accommodation, and the sandstone fraction (SF) may serve as a proxy for the rate of sediment supply. Although previous research shows the effectiveness of applying TSF techniques to sequence stratigraphic analyses in siliciclastic depositional environments, constraints and analytical procedures of the technique are still not clearly illustrated. The paleogeography and sequence stratigraphy of the Cretaceous Gallup system and Ferron Notom deltaic complex in the Western Interior Basin have been extensively studied, providing an opportunity to explore the applicability and detailed workflow of the TSF method. TSF analyses are conducted first on two representative measured sections from the Gallup and the Ferron outcrops, respectively. The TSF analyses of the two one-dimensional (1D) sections are capable of identifying transgressive–regressive (T-R) cycles of the two deltas. However, the 1D sections can reflect the accommodation and sediment supply change only at single locations, which limits their usefulness in identification of stratigraphically consecutive parasequences and composite bounding surfaces. The utility of TSF analyses on cross sections is then tested on a depositional-dip transect of the Gallup delta, as well as dip-oblique and strike-oblique cross sections of the Ferron Notom delta. Parameters of T and SF are acquired from measured sections as well as interpolated virtual sections. For both the Gallup system and the Ferron Notom deltaic complex, the cross-sectional TSF analyses are more effective in recognizing systems tracts and associated bounding surfaces than the TSF analyses in 1D sections. Because dip-oriented cross sections usually encompass both proximal and distal parts of parasequences, and preserve stratigraphically continuous successions, they can provide more complete information for TSF interpretations than strike-oriented cross sections. Above all, TSF analysis via both measured and virtual sections along a depositional-dip profile is inclined to result in sequence stratigraphic categories that best match those based on the full set of geological observations.TSF analyses can also be used to identify general direction of shoreline trajectories in both the Gallup and Ferron Notom deltas. Parameterization of T, SF, and maximum progradation distance for both the Gallup and Ferron Notom parasequences are used to indicate shelf gradients throughout their deposition. The prominent differences of the shelf gradients between different deltaic parasequences indicate differences in allogenic and autogenic controls on the development of T-R sequences in these two deltas.

中文翻译:

用准层序厚度砂岩分数比的方法解释边缘海洋环境中的层序地层:美国西部内陆盆地盖洛普和费伦露头的案例研究

准层序厚度与砂岩分数比 (TSF) 是一种简单但潜在的强大工具,可用于识别硅质碎屑层序中的地层堆积模式和相关系统域。平行层序厚度 (T) 反映了适应性,砂岩分数 (SF) 可以作为沉积物供应速率的代表。尽管先前的研究表明在硅质碎屑沉积环境中应用 TSF 技术进行层序地层分析的有效性,但该技术的限制条件和分析程序仍未清楚说明。对西部内陆盆地白垩纪盖洛普体系和 Ferron Notom 三角洲复合体的古地理和层序地层学进行了广泛研究,为探索 TSF 方法的适用性和详细工作流程提供了机会。TSF 分析首先分别在盖洛普和 Ferron 露头的两个代表性测量剖面上进行。两个一维 (1D) 剖面的 TSF 分析能够识别两个三角洲的海进-海退 (TR) 旋回。然而,一维剖面只能反映单个位置的适应和沉积物供应变化,这限制了它们在识别地层连续平行序列和复合边界表面中的有用性。然后,在盖洛普三角洲的沉积倾角横断面以及 Ferron Notom 三角洲的倾角倾斜和走向倾斜截面上测试 TSF 分析对横截面的效用。T 和 SF 的参数是从测量截面以及插值的虚拟截面中获取的。对于盖洛普系统和 Ferron Notom 三角洲复合体,横截面 TSF 分析在识别系统域和相关边界表面方面比一维截面中的 TSF 分析更有效。因为倾角横断面通常包括近端和远侧层序的部分,并保持地层连续演替,它们可以为 TSF 解释提供比走向横断面更完整的信息。最重要的是,通过沿沉积倾角剖面的测量剖面和虚拟剖面进行的 TSF 分析倾向于产生与基于全套地质观测结果最匹配的层序地层类别。TSF 分析也可用于确定海岸线的大致方向Gallup 和 Ferron Notom 三角洲的轨迹。T的参数化,SF 和 Gallup 和 Ferron Notom 副序列的最大前进距离用于指示整个沉积过程中的陆架梯度。不同三角洲准序列之间陆架梯度的显着差异表明了同种异体和自体控制对这两个三角洲TR序列发育的差异。
更新日期:2022-02-01
down
wechat
bug