weight: bold; mso-font-kerning: 18.0pt" lang=EN-US>Sedimentary Architecture Characteristics of Tidal Bars and Dunes: Taking Roda Sandstone in Pyrenean Foreland Basin, NE Spain as an Example

• 责任者：Ruan Wei (School of Energy Resources ; China University of Geosciences ; Beijing 100083 ; China) ; Huang Jie
• 刊名：Acta Sedimentologica Sinica
• 出版年：2010
• 卷期：28(1)
• 关键词：砂体 ; sand bodies ; 沉积构造 ; sedimentary structure ; 西班牙 ; Spain
• 页码：p.118-127
• 图表：19 illus., 27 refs.
• 分类号：0803
• issnNo：ISSN1000-0550
• isbnNo：CN62-1038/P

The outcrops of Roda Sandstone Ⅲ are located in the southern Pyrenean Foreland Basin, in the northeast of Spain. The key sedimentary structures of the tidal ridges or waves are stacked sets of large scale wedge and tabular cross-strata as well as plane-parallel lamination, ripple lamination. In vertical section, the tidal ridges or waves show a trend of thickening and coarsening upwards. The thickness of tidal bunches vary periodically and the reactivation surfaces are common; double mud drapes are rare, but herringbone cross-strata can be. Bioturbation can be intense in the bottomsets of the cross-bedding. Shell fragments and mud clasts are common. The directions of paleocurrent were polydirectional, but most concentrated on westward direction, which is parallel to acute angle with the orientation of the progradation of delta front. The result suggests the tidal ridges and waves coexisted.