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[1] Oxygen isotope compositions of phosphate from vertebrate tooth enamel were measured to determine the evolution of tropical sea surface (<$200 m depth) O values of fish tooth enamel (up to 22.3%) could reflect the arrival of a cold water current from the Arctic during the opening of the North Sea rift. An apparent large drop of temperatures from 28 to 21°C is identified at the Callovian-Oxfordian boundary over no more than %2-3 Myr. This cooling is compatible with previous paleobotanical and geochemical studies and can be precisely correlated with the migration of boreal ammonites into the Tethyan domain. Because isotopic sea surface temperatures are probably too low to be compatible with tropical climatic conditions, the d 18O value of seawater could have been >0% owing to limited growth of continental ice during the early middle Oxfordian. The resulting sea level fall is estimated to be at least 50 m and is compatible with a global regression stage. The middle Oxfordian thermal minimum is followed by a new warming stage of 3-4°C from the middle to the late Oxfordian.

A new and simple method is developed to efficiently quantify erosion and deposition rates based on stock unearthing measurements. This is applicable to spatial scales ranging from plot to hillslopes, and to time scales ranging from single hydrologic events to centennial scales. The method is applied to a plot area on vineyard hillslopes in Burgundy (Monthélie, France), with measurement of 4328 vine plants. A sediment budget established at the plot scale shows a mean soil lowering of 3.44 ± 1 cm over 20 years, involving a minimal erosion rate of 1.7 ± 0.5 mm yr − 1 . Locally, erosion rates can reach up to 8.2± 0.5 mm yr − 1 .This approach allows the sediment redistribution to be mapped and analyzed at 1-m resolution. It provides novel insights into the characterization of erosion patterns on pluri-decennial scales and into the analysis of spatial distribution of erosion processes on cultivated hillslopes.

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The purpose of this paper is to provide a sediment-flux quantification in a vineyard context (Vosne-Romanée, Burgundy, France) where medium-term soil budget and sustainability are controlled by complex interactions between natural processes (rill erosion) and anthropogenic processes (earth supply transferred back into the rills by the winegrowers). Concentrated overland flows during the rainfall event resulted in the incision of 13 major rills in the inter-rows, carrying a sediment volume of about 4.77 m 3. Most of the rills were rectilinear and displayed a U shape with strong vertical walls. Rill incision began about 30 m from the upper plot boundary. In the buffer zone located at the lower border of the plot, seven fan systems developed from the material originating in one or two contributory rows. Accumulated volume is estimated at 1.6 m 3. Data from grain-size distribution, and rill and fan volumes, show that erosion is dominated by rilling (70% of the sediment yield) over sheet process (30% of the sediment yield). The net exported soil loss, corresponding to the balance between natural soil loss and anthropogenic supply, ranges between 24 ± 3 t ha − 1 and 48 t ha − 1 , over the plot during one hydrologic event. Analyses of the grain-size distribution in the reference soil sample and in the fans reveal that size selectivity has occurred, with preferential export of the fine material (b 63 μm) out of the plot, and preservation of the coarsest fractions (N 2 mm) in the fans. To evaluate the relative importance in grain-size distribution of natural processes (material loss) over anthropogenic processes (rill-filling by winegrowers), we simulated the temporal evolution of grain-size distribution in surface soil during five successive rainfall events. Our results clearly show that more than 30% of fine material in surface soil was lost in these few events, despite anthropogenic rill filling. This fine-fraction removal may have considerable impact on vineyard sustainability.

Displacement rates of normal faults deduced from stratigraphic data are often unreliable. Here we calculate the velocity of motion on a normal fault from the variations in accommodation potential on both sides of the fault within a high‐resolution time‐frame established by biostratigraphy and physical stratigraphy. Our example is the Ornon normal fault bounding the Early Jurassic Bourg‐d'Oisans Basin formed during Tethyan rifting. We show that motion on the fault was discontinuous when examined at high resolution and over a long time interval. During a first interval (Hettangian to Sinemurian Arietites bucklandi zone) a low rate of displacement (=202–423 m Myr−1) coeval with diffused extensional deformation throughout the sedimentary basin is observed. A second interval of localized deformation (Early Sinemurian Caenisites turneri zone) is characterized by higher rates of displacement on the fault (1846 m Myr−1). Our results concur with recent numerical models identifying the main stages of extensional deformation.