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The predominantly carbonate nature of the mountains near the coast of Málaga and Marbella (Costa del Sol, southern Spain) and the presence of springs have favored the formation of travertine buildups during the Quaternary. The geomorphic characteristics of the slopes and the location of the springs have determined the development of three types of travertine growths: (1) spring travertines, located preferentially on the south mountainside, where the slope is steepest; (2) pool-dam-cascade travertines, which form along the north and east edges, far from the carbonate relief and with a gentler slope; and (3) river-valley travertines, formed in the courses of the springs of any sector. Field observations combined with new amino acid racemization (AAR) dating of Helicidae gastropods show that most of the travertine formations are polyphasic and that their development was interrupted by stages of erosion and incision. Five stages of travertine development are evident, most of which are related to warm, moist episodes corresponding to marine oxygen isotope stages (MIS) 7, 5, 3, and 1, although local travertine growth also occurred during MIS 6 and during the transition from MIS 3 to 2. [ABSTRACT FROM AUTHOR]

• Based on alkane indices, three geochemical units (GU) were identified. • GUs represent major contribution of aquatic macrophytes or terrestrial plants. • Paleoenvironmental episodes (PE) produced oscillations in the marsh water level. • PEs were related to sea level and climatic changes, and recent tectonics. • Emersion led to increased amounts of short-chain and branched fatty acids. We reconstructed the paleoenvironmental conditions of the Mazarrón Basin during MIS 7 and MIS 1 based on their alkane and fatty acid contents, their mineralogy and the fossil content of an amino-acid-dated sediment sequence. The n- alkane and fatty acid indices proved to be excellent paleoenvironmental proxies for studying the paleo-hydrogeological and paleoclimatological evolution of this marshland. Three geochemical units (GUs) were identified from the abundance of the C 25 n -alkane and the ACL, TAR HC and P aq values, confirming the importance of phases with terrestrial plant input or aquatic macrophyte predominance. These GUs were used to define three paleoenvironmental episodes (PEs) during MIS 7. In PE7.1, the contribution of algal and aquatic macrophytes predominated in a temporarily flooded saline muddy plain. In PE7.2, the major contribution was from aquatic macrophytes (flooded marsh), although it was marked by episodes of emersion with greater terrestrial contribution. At the top of the MIS 7 record (PE7.3), there was a significant reduction in the water depth, with the main input deriving from terrestrial plants in a muddy alluvial plain. Six PEs were established during MIS 1 (Holocene), of which three predominately received organic matter derived from aquatic macrophytes, while the major contribution in the other three came from terrestrial plants. The two sets of PEs were linked to episodes of increased and decreased water level, respectively. This interpretation is consistent with the characteristics of the sediment facies, with PE1.1, 1.3 and 1.5 corresponding to a marsh with deeper water and a greater input of detrital materials, and PE1.2, 1.4 and 1.6 to a shallow environment with carbonates and gypsum deposits. Direct marine influence was limited, so the oscillations in the water level in the marsh were likely to be more related to climatic changes (drier/wetter phases) and recent tectonics than to large changes in sea level. Emersion led to degradation of the organic matter and enrichment in short-chain and branched saturated fatty acids. [ABSTRACT FROM AUTHOR]

A multiproxy study based on sedimentology, mineralogy, magnetic susceptibility, organic geochemistry and fossil content allowed to establish the sedimentary evolution of palustrine basins and to study the interplay between tectonic and climatic forcings in the sedimentation and facies arrangement that can be extrapolated to other coal-bearing basins. The reinterpretation of the data from 18 cores allowed to determine the facies distribution and to model the sedimentary evolution of the Padul Basin, with the longest continuous continental Quaternary record in the Southwestern Mediterranean region. The Padul Basin sediment record and facies successions provide an outstanding example of tectonically and environmentally controlled sedimentation. The sedimentary characteristics of the cores and thickness distribution revealed that recent tectonics was a more important forcing than other processes (e.g. climate). The influence of recent tectonics was determinant in facies arrangement, that is to say that the activity of a rotated fault produced a differential subsidence, causing more than 100 m of palustrine deposits to stack. On the basis of the sedimentological record combined with data on the mineralogy, fossil content, magnetic susceptibility and total organic carbon, three main sedimentary units were identified, linked to diverse subsidence rates and paleoenvironmental oscillations. The magnetic susceptibility was likely to have been controlled by the organic matter content (TOC values), linked to oxic/anoxic conditions. In the lower part of the record, Unit A (107.0–68.7 m), shallow lacustrine conditions were dominant, with an important influx associated with considerable runoff from active alluvial fans, linked to a higher subsidence rate. Unit B (68.7–37.6 m) had a transitional character, with a considerable decrease in the influence of the alluvial fan system. The lake recharge through overland flow markedly diminished and pre-existing groundwater recharge was dominant. A sudden change to peaty materials indicated that surface runoff was directly diverted to the recently excavated Dúrcal River gorge, thereby precluding the basin from becoming a swampy environment with stagnant waters. Unit C (upper 37.6 m) was almost exclusively fed by bicarbonate groundwater and subsurface runoff through the highly permeable coarse alluvial fan deposits. Within these main sedimentary units, minor mud-peat shallowing-upward sequences were identified. • The facies distribution and sedimentary evolution model along 1 Ma were determined • Recent tectonics was the dominant forcing and determinant in facies arrangement • The Garrido rotated Fault produced a differential subsidence at the NE corner • Sedimentary units showed distinct hydrogeological patterns linked to recent tectonics • Lacustrine conditions dominated at >400 ka; palustrine conditions occurred at <400 ka [ABSTRACT FROM AUTHOR]