Short Communication: Evidence for non-Gaussian distribution of rock weathering rates

S. Emmanuel*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

5 Scopus citations

Abstract

The weathering of rocks influences the geochemistry of the oceans, the erosion of landscapes and man-made structures, and even the global climate. Although a high degree of variance is often observed in rate measurements, little is understood about the statistical characteristics of weathering rate distributions. This preliminary study demonstrates that the weathering rates of limestone, determined from measurements of an ancient eroded limestone edifice, can exhibit highly non-Gaussian behavior. While a Gaussian model produced a poor fit with the data, an alternative model - the generalized extreme value (GEV) framework - was capable of capturing the asymmetric long-tailed distribution, in good agreement with the measured curve. Furthermore, the non-Gaussian distribution of these field rates was found to have similar characteristics to the distribution of rates measured over much smaller microscopic regions of limestone surfaces in laboratory experiments. Such similar behavior could be indicative of analogous chemical and mechanical weathering processes acting over a range of spatial and temporal scales. Moreover, highly asymmetric rate distributions with high variance could be characteristic of rates not only in carbonate rocks, but also in other rock types, suggesting that the use of a small number of measurements to determine field weathering rates may be insufficient to fully characterize the range of rates in natural systems.

Original languageAmerican English
Pages (from-to)441-445
Number of pages5
JournalEarth Surface Dynamics
Volume3
Issue number3
DOIs
StatePublished - 1 Sep 2015

Bibliographical note

Publisher Copyright:
© Author(s) 2015.

Fingerprint

Dive into the research topics of 'Short Communication: Evidence for non-Gaussian distribution of rock weathering rates'. Together they form a unique fingerprint.

Cite this