Figure 8    Vertical aerial photography (left panel) and preliminary morphostratigraphic map (right panel) of Galena Canyon alluvial fan in Death Valley. The morphostratigraphic map is modified after Liu and Dorn (1996). Fan units Qu1 to Qu8 are mapped on the basis of the oldest layering units LU-1 to LU-8 (respectively) observed in varnish microstratigraphy from sampled fan surfaces. Because fan deposits younger than Qu4 (0-24 ka) are difficult to discriminate on the scale of this map, we simply map them as a collective fan unit of Qu1-3. Type layering sequences in varnish from the sampling sites on these fan units (denoted by letters A-F) and their VML age estimates are given in Fig. 9. Note that fan unit Qu8+ was cosmogenically ¹⁰Be dated, yielding two ages of 318 ± 12 and 320 ± 14 ka (Nishiizumi et al., 1993) that are largely consistent with our VML age estimate of > 303 ka for this fan unit.