Estimate the background “inheritance” of ¹⁰Be in the Highway 1 terrace profile (Figure 18.11), and use this to estimate the mean erosion rate in the catchments that once supplying beach sand to this terrace. Assume that the majority of the inheritance arises from exposure during exhumation on hillslopes rather than during translation in the fluvial and littoral systems.

Figure 18.11

Transcribed Image Text:

(a) Depth (cm) 50 F 100 0 200 250 +0 150 OD 300 350 (c) Depth (cm) (e) Depth (cm) 0 0 20 40 60 80 100 120 140 0 0 0 100 200 300 400 500 O 8 0 2 O O 7 1 All terraces tea 4 6 [10Be] 105 atoms g + Terrace 2 Western HOH OH HON e 2 HOM HOH 3 101 H HOH T5 T4 OT3 T2 OT1 8 tot 0.5 1.0 1.5 2.0 2.5 3.0 012 3 4 5 6 7 8 4 H 107 1 2 3 [26 Al] 106 atoms g- OTH Terrace 4 Blackrock 10 5 4 (b) Depth (cm) (d) Depth (cm) (f) 0 0 50 Depth (cm) 100 150 200 250 300 0 50 100 150 0 200 100 150 0.5 200 250 [0Be] 105 atoms g- 0 Terrace 1 Highway 1 0.4 HO 1.0 1.5 2.0 2.5 THO HOM 1 Terrace 3 Wilder JOI 50 Terrace 5 Quarry OP HOM O O KOH H HOM 1 2 3 4 5 6 a 0.8 HOI 11 HH I 1.2 HCH TOPH 0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 HHHH 0 2 4 6 8 10 12 0 HOH IOI HOH 101 M H 1.6 FOT TOIN HOH N FORT HOBH H 2 3 4 5 [26 Al] 106 atoms g- 3.0 HO 7 HH 6 7