highly significantp<0.0001
Such a mechanism is further suggested by the highly significant regressions (p<0.0001) between log(pCO 2 ) and the estimated contribution of carbonate weathering to TA (R 2 = 0.38), or with Si/Ca 2+ ratios (R 2 = 0.35), i.e.,rock weathering would explain close to 35% of the variance of pCO 2 .