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La sedimentación durante el Jurásico terminal y el Cretácico inferior en la Cuenca de Los Cameros se desarrolla en cuatro Secuencias deposicionales de forma tal que todas comienzan con facies siliciclásticas fluviales y terminan (excepto la IV) con facies calcáreas de origen lacustre. El control tectónico durante la sedimentación es muy claro y se manifiesta de diversas maneras y escalas, pero el control eustático también parece jugar un papel importante. Para estudiar estos factores se ha analizado con detalle una de las etapas lacustres en la cuenca, concretamente la que termina la Secuencia deposicional III (Barremiense - Aptiense), y se ha elegido la franja mas nororiental de la misma. En esta unidad (la Formación Calizas de Leza), y en ese sector, se ha realizado un análisis sedimentológico detallado identificando cuatro grupos de facies que corresponden a la sedimentación en lagos carbonáticos costeros, con etapas de influencia marina neta. También se ha reconstruido la cuenca para la etapa Barremiense - Aptiense, que formaba una gran rampa basculada hacia el NE, en cuyo borde nororiental se desarrollaba la sedimentación lacustre-costera que nos ocupa. La influencia marina proviene del SE, del Tetis, ya que durante esa etapa en el resto de la cuenca Ibérica se produjo la mas importante transgresión del Cretácico inferior en la zona. Por otro lado, la Formación Leza está formada por seis litosomas carbonáticos claramente diferenciados, limitados por paleofracturas que funcionaron durante la sedimentación de la unidad y que fueron fosilizadas posteriormente. El control tectónico está ejercido por una fractura de bajo ángulo en el margen noreste, buzando hacia el sur, que durante la etapa distensiva, de formación de la cuenca, actuó como “detachment” y que durante la etapa de inversión alpina actuó de nuevo originando un cabalgamiento de cerca de 30 km claramente apreciable en los perfiles sísmicos disponibles., The sediment infilling of the Cameros Basin during the Latest Jurassic and Early Cretaceous can be separated into four depositional sequences, using unconformities as the key. Each sequence starts with rocks of fluviatile facies and ends with lacustrine carbonates. The Leza Formation belongs to the Depositional sequence III (Barremian - Aptian) and corresponds to the lacustrine facies that developed in the northeastern margin of the basin in the upper part of the sequence. It is a particularly suitable unit for studying the main factors that controlled sedimentation (tectonic and eustasy) because it shows marine influence at several levels (the age of which has been determined), and the synsedimentary tectonic (growth faults and slumps) were very active in that margin, due to the existence of a low angle main listric fault which limited the basin in the NE. The sedimentological analysis of facies and palaeogeographical maps show that the Leza Formation is divided into six bodies or lithosomes, corresponding to six paleolakes, limited by synsedimentary faults. These were finally buried and preserved by the overlying formation. However, the lakes were not isolated as the marine transgression, coming from the southeast (Tetbys), afected aH of them. This transgresion occurred during the Lower Aptian, the moment when the sea level was highest in the Iberian Trough during the Early Cretaceous, so that, the drainage from the continental aeras was insuficient (great amounts of water were retained in the basin and, therefore, led to the development of important acumulations of rocks of lacustrine facies). The major tectonic control was due to the movement of the low angle listrie fault (NW - SE) that dips southwestwards, that actuated as a detachment during the distensive stage (basin formation). That event was acompanied by the development of a systcm of parallel and orthogonal faults that produced the small basins where sedimentation of the rocks of the Leza Formation took, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

© 2015This review provides a synopsis of ongoing research and our understanding of the fundamentals of sea-level change today and in the geologic record, especially as illustrated by conditions and processes during the Cretaceous greenhouse climate episode. We give an overview of the state of the art of our understanding on eustatic (global) versus relative (regional) sea level, as well as long-term versus short-term fluctuations and their drivers. In the context of the focus of UNESCO-IUGS/IGCP project 609 on Cretaceous eustatic, short-term sea-level and climate changes, we evaluate the possible evidence for glacio-eustasy versus alternative or additional mechanisms for continental water storage and release for the Cretaceous greenhouse and hothouse phases during which the presence of larger continental ice shields is considered unlikely. Increasing evidence in the literature suggests a correlation between long-period orbital cycles and depositional cycles that reflect sea-level fluctuations, implying a globally synchronized forcing of (eustatic) sea level. Fourth-order depositional sequences seem to be related to a ~ 405 ka periodicity, which most likely represents long-period orbital eccentricity control on sea level and depositional cycles. Third-order cyclicity, expressed as time-synchronous sea level falls of ~ 20 to 110 m on ~ 0.5 to 3.0 Ma timescales in the Cretaceous, are increasingly recognized as connected to climate cycles triggered by long-term astronomical cycles that have periodicity ranging from ~ 1.0 to 2.4 Ma. Future perspectives of research on greenhouse sea-level changes comprise a high-precision time-scale for sequence stratigraphy and eustatic sea-level changes and high-resolution marine to non-marine stratigraphic correlation.

© 2015 Elsevier LtdIn their recent paper, Farouk and El-Sorogy (2015) present a reconstruction of the Danian–Selandian relative sea-level changes for the Western Desert of Egypt and an interpretation of eustatic versus tectonic controls on the latter. However, the relative sea-level changes should be distinguished from the shoreline shifts (also for the purposes of inter-regional comparisons). From three alternative global curves, two confirm the authors’ conclusions, although it is questionable whether these curves are suitable for the purposes of such an analysis. It cannot be excluded that the relative sea-level fall in the late Danian was caused by the same regional tectonic uplift that resulted in the hiatus at the Danian/Selandian boundary. More research (including quantitative palaeobathymetric modelling) is necessary to understand the relative importance of the eustatic and tectonic controls on the sea-level changes established in the Western Desert of Egypt.

© 2015. This review provides a synopsis of ongoing research and our understanding of the fundamentals of sea-level change today and in the geologic record, especially as illustrated by conditions and processes during the Cretaceous greenhouse climate episode. We give an overview of the state of the art of our understanding on eustatic (global) versus relative (regional) sea level, as well as long-term versus short-term fluctuations and their drivers. In the context of the focus of UNESCO-IUGS/IGCP project 609 on Cretaceous eustatic, short-term sea-level and climate changes, we evaluate the possible evidence for glacio-eustasy versus alternative or additional mechanisms for continental water storage and release for the Cretaceous greenhouse and hothouse phases during which the presence of larger continental ice shields is considered unlikely. Increasing evidence in the literature suggests a correlation between long-period orbital cycles and depositional cycles that reflect sea-level fluctuations, implying a globally synchronized forcing of (eustatic) sea level. Fourth-order depositional sequences seem to be related to a ~. 405. ka periodicity, which most likely represents long-period orbital eccentricity control on sea level and depositional cycles. Third-order cyclicity, expressed as time-synchronous sea level falls of ~. 20 to 110. m on ~. 0.5 to 3.0. Ma timescales in the Cretaceous, are increasingly recognized as connected to climate cycles triggered by long-term astronomical cycles that have periodicity ranging from ~. 1.0 to 2.4. Ma. Future perspectives of research on greenhouse sea-level changes comprise a high-precision time-scale for sequence stratigraphy and eustatic sea-level changes and high-resolution marine to non-marine stratigraphic correlation.

© 2014 Elsevier B.V. A methodical approach to identifying major abiotic events in the siliciclastic succession accumulated in the shallow epicontinental basin on the Eastern Russian Platform during the Early Cretaceous is presented. On the basis of a reliable chronostratigraphic framework a comparison between global and regional sea level curves was undertaken. The intervals during which the global and regional sea level curve trends are similar correspond to a predominance of eustasy in the particular basin. Alternatively, tectonic activity dominates during intervals when there is no similarity between the trends of the global and regional sea level curves. Three intervals of noncoincidences of trends of these two curves matched with major tectonic events that took place within the Eastern Russian Platform in the Early Cretaceous: the Early Hauterivian tectonic uplift, subsequent Late Hauterivian subsidence and the Late Albian uplift. The main consequences of the tectonic activity were two large regional unconformities and hiati. The comparison of main global and regional sea level trends also reveals major climatic events. "The cold snaps" that occurred during the Early Cretaceous greenhouse world (Hu et al., 2012) coincided with simultaneous global and regional sea level lowstands, peak shallowing of the basin and the almost complete absence of sediments. "The cold snap" is identified in the Late Aptian sedimentary sequences on the Eastern Russian Platform.

© 2015 Elsevier Ltd. In their recent paper, Farouk and El-Sorogy (2015) present a reconstruction of the Danian-Selandian relative sea-level changes for the Western Desert of Egypt and an interpretation of eustatic versus tectonic controls on the latter. However, the relative sea-level changes should be distinguished from the shoreline shifts (also for the purposes of inter-regional comparisons). From three alternative global curves, two confirm the authors' conclusions, although it is questionable whether these curves are suitable for the purposes of such an analysis. It cannot be excluded that the relative sea-level fall in the late Danian was caused by the same regional tectonic uplift that resulted in the hiatus at the Danian/Selandian boundary. More research (including quantitative palaeobathymetric modelling) is necessary to understand the relative importance of the eustatic and tectonic controls on the sea-level changes established in the Western Desert of Egypt.

© 2014. This study presents new data on transgressive-regressive and accommodation-sedimentation regimes in the eastern Russian Plate during the Middle Jurassic-Lower Cretaceous. The proposed generalized scheme illustrating the combined effects of three major factors (eustasy, tectonic "noise", and depositional gradient) controlling the deposition of sequences with different stratal architecture allowed us to quantify the parameters of sedimentation (5S) and accommodation (5A) for second- and third-order cycles. A distinctive feature of the evolution of the Middle Jurassic-Lower Cretaceous sedimentary basin is the excess of accommodation space over sediment supply, which was not conducive to creation of clinoforms. The difference between stacking patterns in individual time intervals and the estimated values of 5A/5S may be indicative of the presence of unidentified stratigraphic breaks in the Bathonian and Late Tithonian-Berriasian, which were accompanied by erosion and reworking of sand strata. The stepwise regressive-transgressive deepening during the Oxfordian-Early Tithonian and transgressive-regressive shallowing during the Late Tithonian-Berriasian were probably caused by short-term manifestations of local tectonic "noise", and depositional hiatuses accompanied by the erosion of missing elements in the structure of third-order cycles. The Lower Cretaceous succession exhibits no mismatch between transgressive-regressive and retrogradational-progradational cycling, which provides another supporting evidence for a quiet tectonoeustatic and sedimentation regime during the Early Cretaceous compared to that of Middle-Late Jurassic time.

© 2015This review provides a synopsis of ongoing research and our understanding of the fundamentals of sea-level change today and in the geologic record, especially as illustrated by conditions and processes during the Cretaceous greenhouse climate episode. We give an overview of the state of the art of our understanding on eustatic (global) versus relative (regional) sea level, as well as long-term versus short-term fluctuations and their drivers. In the context of the focus of UNESCO-IUGS/IGCP project 609 on Cretaceous eustatic, short-term sea-level and climate changes, we evaluate the possible evidence for glacio-eustasy versus alternative or additional mechanisms for continental water storage and release for the Cretaceous greenhouse and hothouse phases during which the presence of larger continental ice shields is considered unlikely. Increasing evidence in the literature suggests a correlation between long-period orbital cycles and depositional cycles that reflect sea-level fluctuations, implying a globally synchronized forcing of (eustatic) sea level. Fourth-order depositional sequences seem to be related to a ~ 405 ka periodicity, which most likely represents long-period orbital eccentricity control on sea level and depositional cycles. Third-order cyclicity, expressed as time-synchronous sea level falls of ~ 20 to 110 m on ~ 0.5 to 3.0 Ma timescales in the Cretaceous, are increasingly recognized as connected to climate cycles triggered by long-term astronomical cycles that have periodicity ranging from ~ 1.0 to 2.4 Ma. Future perspectives of research on greenhouse sea-level changes comprise a high-precision time-scale for sequence stratigraphy and eustatic sea-level changes and high-resolution marine to non-marine stratigraphic correlation.

© 2015 Elsevier LtdIn their recent paper, Farouk and El-Sorogy (2015) present a reconstruction of the Danian–Selandian relative sea-level changes for the Western Desert of Egypt and an interpretation of eustatic versus tectonic controls on the latter. However, the relative sea-level changes should be distinguished from the shoreline shifts (also for the purposes of inter-regional comparisons). From three alternative global curves, two confirm the authors’ conclusions, although it is questionable whether these curves are suitable for the purposes of such an analysis. It cannot be excluded that the relative sea-level fall in the late Danian was caused by the same regional tectonic uplift that resulted in the hiatus at the Danian/Selandian boundary. More research (including quantitative palaeobathymetric modelling) is necessary to understand the relative importance of the eustatic and tectonic controls on the sea-level changes established in the Western Desert of Egypt.

© 2014. This study presents new data on transgressive-regressive and accommodation-sedimentation regimes in the eastern Russian Plate during the Middle Jurassic-Lower Cretaceous. The proposed generalized scheme illustrating the combined effects of three major factors (eustasy, tectonic "noise", and depositional gradient) controlling the deposition of sequences with different stratal architecture allowed us to quantify the parameters of sedimentation (5S) and accommodation (5A) for second- and third-order cycles. A distinctive feature of the evolution of the Middle Jurassic-Lower Cretaceous sedimentary basin is the excess of accommodation space over sediment supply, which was not conducive to creation of clinoforms. The difference between stacking patterns in individual time intervals and the estimated values of 5A/5S may be indicative of the presence of unidentified stratigraphic breaks in the Bathonian and Late Tithonian-Berriasian, which were accompanied by erosion and reworking of sand strata. The stepwise regressive-transgressive deepening during the Oxfordian-Early Tithonian and transgressive-regressive shallowing during the Late Tithonian-Berriasian were probably caused by short-term manifestations of local tectonic "noise", and depositional hiatuses accompanied by the erosion of missing elements in the structure of third-order cycles. The Lower Cretaceous succession exhibits no mismatch between transgressive-regressive and retrogradational-progradational cycling, which provides another supporting evidence for a quiet tectonoeustatic and sedimentation regime during the Early Cretaceous compared to that of Middle-Late Jurassic time.

© 2015 Elsevier Ltd. In their recent paper, Farouk and El-Sorogy (2015) present a reconstruction of the Danian-Selandian relative sea-level changes for the Western Desert of Egypt and an interpretation of eustatic versus tectonic controls on the latter. However, the relative sea-level changes should be distinguished from the shoreline shifts (also for the purposes of inter-regional comparisons). From three alternative global curves, two confirm the authors' conclusions, although it is questionable whether these curves are suitable for the purposes of such an analysis. It cannot be excluded that the relative sea-level fall in the late Danian was caused by the same regional tectonic uplift that resulted in the hiatus at the Danian/Selandian boundary. More research (including quantitative palaeobathymetric modelling) is necessary to understand the relative importance of the eustatic and tectonic controls on the sea-level changes established in the Western Desert of Egypt.

© 2014 Elsevier B.V. A methodical approach to identifying major abiotic events in the siliciclastic succession accumulated in the shallow epicontinental basin on the Eastern Russian Platform during the Early Cretaceous is presented. On the basis of a reliable chronostratigraphic framework a comparison between global and regional sea level curves was undertaken. The intervals during which the global and regional sea level curve trends are similar correspond to a predominance of eustasy in the particular basin. Alternatively, tectonic activity dominates during intervals when there is no similarity between the trends of the global and regional sea level curves. Three intervals of noncoincidences of trends of these two curves matched with major tectonic events that took place within the Eastern Russian Platform in the Early Cretaceous: the Early Hauterivian tectonic uplift, subsequent Late Hauterivian subsidence and the Late Albian uplift. The main consequences of the tectonic activity were two large regional unconformities and hiati. The comparison of main global and regional sea level trends also reveals major climatic events. "The cold snaps" that occurred during the Early Cretaceous greenhouse world (Hu et al., 2012) coincided with simultaneous global and regional sea level lowstands, peak shallowing of the basin and the almost complete absence of sediments. "The cold snap" is identified in the Late Aptian sedimentary sequences on the Eastern Russian Platform.

© 2015. This review provides a synopsis of ongoing research and our understanding of the fundamentals of sea-level change today and in the geologic record, especially as illustrated by conditions and processes during the Cretaceous greenhouse climate episode. We give an overview of the state of the art of our understanding on eustatic (global) versus relative (regional) sea level, as well as long-term versus short-term fluctuations and their drivers. In the context of the focus of UNESCO-IUGS/IGCP project 609 on Cretaceous eustatic, short-term sea-level and climate changes, we evaluate the possible evidence for glacio-eustasy versus alternative or additional mechanisms for continental water storage and release for the Cretaceous greenhouse and hothouse phases during which the presence of larger continental ice shields is considered unlikely. Increasing evidence in the literature suggests a correlation between long-period orbital cycles and depositional cycles that reflect sea-level fluctuations, implying a globally synchronized forcing of (eustatic) sea level. Fourth-order depositional sequences seem to be related to a ~. 405. ka periodicity, which most likely represents long-period orbital eccentricity control on sea level and depositional cycles. Third-order cyclicity, expressed as time-synchronous sea level falls of ~. 20 to 110. m on ~. 0.5 to 3.0. Ma timescales in the Cretaceous, are increasingly recognized as connected to climate cycles triggered by long-term astronomical cycles that have periodicity ranging from ~. 1.0 to 2.4. Ma. Future perspectives of research on greenhouse sea-level changes comprise a high-precision time-scale for sequence stratigraphy and eustatic sea-level changes and high-resolution marine to non-marine stratigraphic correlation.