『Abstract
Basaltic bedrock dissolves quickly, and its weathering rate is therefore important towards controlling the composition of natural waters, soil formation, and CO2 concentrations in the atmosphere. despite its importance, however, few reports of basalt or diabase and gabbro weathering rates exist in the literature, and most have been measured in laboratory dissolution experiments or based on watershed studies. Here, using elemental profiles measured through regolith on a Jurassic diabase dike in south-central Pennsylvania,we calculate time-integrated log dissolution rates (mol m^-2 s^-1) of the primary minerals plagioclase (-14.9 s^-1) and augite (-14.8), and of smectite (-17.6), a secondary clay mineral formed in the soil. Characteristic patterns in elemental profiles are consistent with preserved signatures of corestone formation. Elemental and mineral signatures of the soils relative to the parent rock are compared to predictions from citrate-containing basalt column dissolution experiments. Depletion of apatite and of Al,Fe, Mn, Ti, P, Y, Ni, Cr, Sc, V, Ga, Cu, Zn, and La are observed in the upper meter of the profile relative to the parent rock.

Keywords: Basalt; Diabase; Weathering; Trace elements; Biosignature』

1. Introduction
2. Methods
　2.1. Field site and sample collection
　2.2. Bulk chemistry
　2.3. Scanning electron microscopy
　2.4. X-ray diffraction (XRD)
　2.5. Water content and bulk density
　2.6. Pore water concentrations and pH
3. Results
　3.1. Parent material and soil characterization
　3.2. Mass-element transfer coefficient
　3.3. SEM
　3.4. Model mineral abundances　
　3.5. Mineralogical profiles
　3.6. Water content and pore water chemistry
　3.7. Clay fraction percentage and bulk density
4. Discussion
　4.1. Elemental and mineralogical weathering profiles
　4.2. Surface-area normalized dissolution rates
　4.3. Trace elements as organomarkers
5. Conclusions
Acknowledgements
Appendix A. Supplementary data
References