Controls on dripwater chemistry of Oregon Caves National Monument, Northwestern United States

Rushdi, Ahmed, Ersek, Vasile, Mix, Alan and Clark, Peter (2018) Controls on dripwater chemistry of Oregon Caves National Monument, Northwestern United States. Journal of Hydrology, 557. pp. 30-40. ISSN 0022-1694

[img] Text
Rushdi-2018-J_Hydrology.pdf - Accepted Version
Restricted to Repository staff only until 6 December 2018.

Download (895kB) | Request a copy
Official URL: https://doi.org/10.1016/j.jhydrol.2017.12.006

Abstract

Cave dripwater chemistry of Oregon Caves National Monument (OCNM) was studied, where the parameters pH, total alkalinity, calcium, magnesium, strontium, sodium and barium were analyzed at quasi-monthly intervals from 2005 to 2007. Different statistical analyses have been used to investigate the variability of the chemical parameters in the different sites in the OCNM cave system. The dripwater varies in response to seasonal changes in rainfall. The drip rates range from zero in summer to continuous flow in winter, closely following the rainfall intensity. Spatial variations of dripwater chemistry, which is nonlinearly related to dripwater discharge likely, reflect the chemical composition of bedrock and overlying soil, and the residence time of the ground water within the aquifer. The residence time of infiltrated water in bedrock cracks control the dissolution carbonate bedrock, reprecipitation of calcium carbonate and the degree of saturation of dripwater with respect to calcium carbonate minerals. Spatiotemporal fluctuations of dripwater Mg/Ca and Sr/Ca ratios are controlled by dissolution of carbonate bedrock and the degree of calcite reprecipitation in bedrock cracks. This suggests that trace elements in speleothem deposits at the OCNM may serve as paleoclimatological proxies for precipitation, if interpreted within the context of understanding local bedrock chemistry.

Item Type: Article
Uncontrolled Keywords: OCNM; Oregon; Speleothem; Geochemistry; Dripwater; Mg/Ca; Sr/Ca
Subjects: F100 Chemistry
F800 Physical and Terrestrial Geographical and Environmental Sciences
Department: Faculties > Engineering and Environment > Geography and Environmental Sciences
Depositing User: Becky Skoyles
Date Deposited: 11 Dec 2017 11:34
Last Modified: 12 Apr 2018 12:41
URI: http://nrl.northumbria.ac.uk/id/eprint/32777

Actions (login required)

View Item View Item

Downloads

Downloads per month over past year

View more statistics


Policies: NRL Policies | NRL University Deposit Policy | NRL Deposit Licence