Reply to Comment on "On the importance of opal, carbonate, and lithogenic clays in scavenging and fractionating ²³⁰Th, ²³¹Pa and ¹⁰Be in the ocean"

We extend our analysis of the Chase et al. data [Earth and Planetary Science Letters 204 (2002) 215-229] to those other than from the equatorial Pacific and the Southern Ocean. The analysis offers support to our previous conclusion that K_d(Th) for carbonate is on the order of ∼ 1.0 × 10⁶ g/g, or about two orders of magnitude smaller than that for open-ocean lithogenics. There is a lowering of K_d(Th) of lithogenics at high-lithogenic sites attributable to factors including the sediment remobilization from ocean-margin deposits. But the lowered K_d(Th) of lithogenics is still about one order of magnitude greater than that of carbonate at those high-lithogenic sites. Using an independent method, we estimate that K_d,l(Th) is > (2.2 ± 0.9) × 10⁸ g/g at stations adjacent to our EqPac sites, reinforcing our conclusion that the major scavenger for ²³⁰Th is lithogenic, not carbonate particles, even in the low-lithogenic open ocean.