RESUMEN· La cuenca de Vallcebre (cabecera del río Llobregat) muestra una importante variedad de usos del suelo y ambientes geomorfológicos: bosques, pastos, terrazas cultivadas y abandonadas, y cárcavas. Esto ha llevado a la selección de tres cuenca integradas (Cal

The Spanish Mediterranean river basin provides a good background for studying floods from documentary and bibliographical sources within the specialty of historical climatology. This study region's long history of human occupation and climatic conditions together determine a high risk of flooding. As a result, there exists an enormous amount of documentary heritage containing flood information. However, the heterogeneity of documentary sources and different approaches to classifying floods through historical documents can generate some biases and uncertainties about the quantity and quality of the available data. For this reason, this paper proposes a methodology for reconstructing historical floods based on cross-referencing documentary sources. This approach, together with additional archival work, has allowed us to increase the number of flood series for the Spanish Mediterranean coast by 17% and has generated a surprising increase of 233% in the number of flood cases detected. The data obtained have allowed us to analyze the variability of floods and their relationship with climatic and social factors from the fourteenth century to the present. Different climatic oscillations related to the Little Ice Age are detected between the 14th and 19th centuries. Additionally, we detected a strong influence of the defense infrastructures and urban growth, which explain the recent flood trends. However, the difficulty in analyzing the influence of social factors on long-term flood behavior invites us to reflect on the need for further work for emphasizing these issues.

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The eastern sector of the epicontinental Iberian platform underwent restriction after the sedimentation of the lower Muschelkalk carbonates (Middle Triassic) under extensional regime. This resulted in the accumulation of the marine evaporites and the alluvial siliciclastics of the middle Muschelkalk facies in the Triassic Catalan basin, which varied between 100 and 120 m in thickness. This facies consists of three lithostratigraphic units sedimented at basin scale (Lower, Middle and Upper), each of which includes a distinct evaporite unit. In the Lower Unit, the evaporitic sedimentation started as a transgressive sulfate lagoon (Paüls Gypsum unit). During the Middle Unit time, a regressive evaporitic mudflat, made up of a mosaic of shallow gypsum salinas surrounded by anhydrite sabkhas (Arbolí Gypsum unit) developed; in the northeastern half of the basin, an alluvial plain was formed by siliciclastics (Guanta Sandstone unit) of a west and northwest provenance (Lleida High). During the Upper Unit time, a new transgressive sulfate lagoon occupied the southern half of the basin (Camposines Gypsum), whereas an evaporitic mudflat of red-to-variegated mudstones, marls, and lacustrine carbonates developed in the northern half. Cyclic sedimentation was mainly recorded in the evaporitic mudflat-alluvial plain complex of the Middle Unit. The sulfur isotopic values of gypsum in the three evaporite units show a decrease in δ 34 S with time and also a clear distinction from the values of the Keuper facies in the basin. A division of the lithostratigraphic succession into two third-order depositional sequences is proposed. The middle Muschelkalk succession in the Catalan basin is compared with the equivalent one in the subsurface of the adjacent Triassic Maestrat basin, which was filled with >600 m of marine evaporites.