Hydrogeology of Montserrat review and new insights

Hemmings, Brioch; Whitaker, Fiona; Gottsmann, Joachim; Hughes, Andrew. 2015 Hydrogeology of Montserrat review and new insights. Journal of Hydrology: Regional Studies, 3. 1-30. 10.1016/j.ejrh.2014.08.008

Before downloading, please read NORA policies.

Preview

Text (Open Access Paper) 1-s2.0-S2214581814000299-main.pdf - Published Version Available under License Creative Commons Attribution. Download (4MB) | Preview

Abstract/Summary

Study region The tropical, active volcanic arc island of Montserrat, Lesser Antilles, Caribbean. Study focus New insights into hydrological recharge distribution, measurements of aquifer permeability, and geological and hydrological field observations from Montserrat are combined with a review of the current understanding of volcanic island hydrology. The aim is to begin to develop a conceptual model for the hydrology of Montserrat, and to inform and stimulate further investigation into the hydrology of volcanic arc islands, by combining a review of the current understanding of essential components of the hydrological system with fresh analysis of existing data, and new observations, data collection and analysis. This study provides new insights into hydrological recharge distribution, measurements of aquifer permeability, and geological and hydrological field observations from Montserrat. New hydrological insights for the region A new groundwater recharge model predicts whole island recharge of 266 mm/year, between 10% and 20% of annual rainfall. Core scale permeability tests reveal ranges from 10−14 to 10−12 m2 for volcaniclastic rocks with coarse matrix, to a minimum of 10−18 m2 for andesitic lavas and volcaniclastics with fine or altered matrix. Analysis of historical pumping tests on aquifers in reworked, channel and alluvial sediment indicate permeabilities ∼10−10 m2. Springs at elevations between 200 and 400 m above mean sea level on Centre Hills currently discharge over 45 L/s. High discharge require a reasonably laterally continuous low permeability body. Contrasting conceptual models are presented to illustrate two potential hydrogeological scenarios. New field observations also reveal systematic spatial variations in spring water temperature and specific electrical conductivity indicating that meteoric waters supplying the springs are mixed with a deeper groundwater source at some sites.

Item Type:	Publication - Article
Digital Object Identifier (DOI):	10.1016/j.ejrh.2014.08.008
ISSN:	22145818
Additional Keywords:	GroundwaterBGS, Groundwater, Groundwater resources, Groundwater development
Date made live:	13 Jan 2015 14:31 +0 (UTC)
URI:	https://nora.nerc.ac.uk/id/eprint/509378

Actions (login required)

View Item

Document Downloads

More statistics for this item...