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@Article{RossettiAlveVale:2017:TeLaHo,
               author = "Rossetti, Dilce de F{\'a}tima and Alves, F{\'a}bio C. and 
                         Valeriano, M{\'a}rcio de Morisson",
          affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and {Instituto 
                         Nacional de Pesquisas Espaciais (INPE)} and {Instituto Nacional de 
                         Pesquisas Espaciais (INPE)}",
                title = "A tectonically-triggered late Holocene seismite in the southern 
                         Amazonian lowlands, Brazil",
              journal = "Sedimentary Geology",
                 year = "2017",
               volume = "358",
                pages = "70--83",
                month = "Aug.",
             keywords = "Soft-sediment deformation structureMorphostructural 
                         analysisSeismiteFault reactivationAmazonia.",
             abstract = "Definitive criteria for identifying the triggers of soft-sediment 
                         deformation structures (SSDSs) from sedimentary deposits are still 
                         under construction. In this work, we aimed to contribute to 
                         advancing this issue describing the sedimentological 
                         characteristics of an interval of SSDSs formed in a region of the 
                         Amazonian lowlands having numerous morphostructural evidences of 
                         neotectonic reactivation. The deformed interval is 1.5 m thick and 
                         consists of load and flame structures interbedded with massive 
                         beds sandwiched between well-stratified deposits of a fluvial 
                         sandy channel succession with a radiocarbon age of 13011382 cal yr 
                         BP. The SSDSs are intercepted by numerous small-scale, normal 
                         graded-faults. The most interesting is that these faults display 
                         segmented, NW-SE trending planes that propagate upward after 
                         horizontal displacements of a few millimeters. Processes intrinsic 
                         to channel dynamics could not justify this fault morphology, which 
                         is related to recurrent short-lived seismic perturbations with 
                         intervening sedimentation following a main tremor. A relation to 
                         fault reactivation is proposed with basis on the fault trend 
                         compatible with the regional structural pattern and the numerous 
                         morphostructural anomalies verified in the study area, including: 
                         trellis and sub-trellis drainage; rectangular and, to a less 
                         extent, annular channels; anomalously enlarged channels; 
                         orthogonal channels and valleys; channel captures; sudden changes 
                         in channel morphology; moderate to high basin asymmetry factor (AF 
                         between 10 and 27); moderate to high transverse topography 
                         symmetry factor (T = 0.30.5); and anomalous longitudinal river 
                         profiles, with concavity values (11 to 30%) indicative of rivers 
                         in process of adjustments. The morphology of the fault-graded beds 
                         described herein might constitute a feature of relevance for 
                         identifying seismites in other fluvial deposits.",
                  doi = "10.1016/j.sedgeo.2017.07.003",
                  url = "http://dx.doi.org/10.1016/j.sedgeo.2017.07.003",
                 issn = "0037-0738",
             language = "en",
           targetfile = "rossetti_tectonically.pdf",
        urlaccessdate = "30 nov. 2020"
}


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