FIGURE 4

Figure 4: Comparison of accumulation rate data derived from NBCP cyclostratigraphy (a) and various basin-filling models (b and c). The various accumulation rate data sets were normalized by the maximum accumulation rate in each data set to facilitate comparisons. The numbered curves in (b) and (c) were derived from vertical drill holes through the model rift basin shown in (c). NBCP data in (a) are based on a composite reference section scaled to the Rutgers core. Curve 2 in (b) fits the Newark basin data best, but fails to reproduce the marked increase in accumulation rates at ~27.5 M.yr. since the onset of extension (Early Jurassic extrusive interval). (d) Cumulative stratigraphic thickness versus geologic age for various exposed rift basins in eastern North America. The Culpeper (C), Deerfield (D), Fundy (F), Hartford (H), and Newark (N) basins all show pronounced increases in stratal thickness in earliest Jurassic time (extrusive interval). Other abbreviations are DR, Deep River; DV, Danville; and R, Richmond basins. Modified from Schlische and Anders (1996) and Schlische (1999).