The assignment of drainage direction over flat surfaces in raster digital elevation models

Characterization of fluvial activity in Parana Valles using different age-dating techniques

“…The original algorithm is called the D8 flow model, but there have been several advances of this model through time that allow better computation of divergent flows on hillslope, such as the D-1 model (Tarboton, 1997) and the Mass Flux Method (Costa-Cabral and Burges, 1994), as well as flow over flat terrain (Garbrecht and Martz, 1997). For simplicity, we only describe the D8 flow model, which determines the flow direction from every grid cell in a DEM by calculating the steepest downhill slope from a grid cell to the eight surrounding grid cells.…”

Development and application of a new algorithm for automated pit removal for grid DEMs

“…Consequently, after pit removal, both inherent and newly introduced flat surfaces need further processing. Tribe (1992) and Garbrecht & Martz (1997) have proposed elevation modification methods to generate convergent flow patterns over flat areas, and Nogami (1998) presented a random method to process flat areas. However, the elevation increments and hence related drainage slopes in these methods also lack a physical basis.…”

“…Hutchinson (1989) has proposed an algorithm to create pit free DEMs, but most grid DEMs have not been created by this method (Tribe, 1992). In natural landscapes, particularly in those that are large scale, pits and flat surfaces are relatively rare (Mark, 1984;Garbrecht & Martz, 1997;Tribe, 1992), but in currently available grid DEMs, about 5% of grid points are pits (as found in a preliminary investigation by the authors). It is recognized that pits originate from errors of data collection systems, and/or from horizontal and vertical resolutions of DEMs (O'Callaghan & Mark, 1984).…”

Extraction and representation of nested catchment areas from digital elevation models in lake‐dominated topography

“…During pit filling, a surface is formed by filling a pit to some new pour height. This produces a surface through which flow paths can be inferred from the surrounding topography [Garbrecht and Martz, 1997]. Slope tolerances permit flow connections as long as the slope gradient of a cell is below some threshold value.…”

“…Features that fail to completely mark during the optimization process after a fixed number of iterations are marked using the lake boundary following algorithm. An alternative solution could use a Gatbrecht and Martz [1997] or a similar algorithm in these areas, since they are identified prior to slope tracking. (Table 1).…”