Spatial Distribution of Sedimentation Rates

The obtained linear sedimentation and bulk sediment accumulation rates represent average values for the past 100 years. The respective values are 93.4 66.1 mm/100 year for the longterm linear sedimentation rate and 129 111.3 gZ/m year) for the sediment accumulation rate (Hille et al., 2006). 

Both the long-term linear sedimentation and the sediment accumulation rates show similar spatial patterns (Fig. 14.8). 

They reach their highest values in the NE part of the study area and have a second, but much smaller, local maximum in the SW part. The remaining areas are characterized by much lower rates. The variability in both cases is extremely high. The differences between the lowest and highest values for each parameter are in the order of one magnitude. 

We hypothesize that the development of nonuniform distribution of both linear and sediment accumulation rates is related to the course of the rim current at the Gotland Deep. Empirical measLuements of near-bottom currents are rare (e.g., Hagen and Feistel, 2001 Hagen and Feistel, 2004). Hence, near-bottom velocities were derived from a 3D model (Fig. 14.9 Schmidt, personnel communication). 

FIGURE 14.8 Spatial distribution of long-term average (100 years) linear sedimentation rates (LSRIOO) and sediment mass accumulation rates (MAR). Gray crosses indicate the location of sampling stations. 

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