Home / Regular Issue / JST Vol. 20 (2) Jul. 2012 / JST-0284-2011

 

Groundwater from Fractured Granite and Metasedimentary Rocks in the West Coast of Peninsular Malaysia

Nasiman Sapari, Raja Zainariah Raja Azie and Hisyam Jusoh

Pertanika Journal of Science & Technology, Volume 20, Issue 2, July 2012

Keywords: Discharge rates, groundwater, granite, sedimentary rocks, tubewells, usage

Published on:

Hard rock formations consisting of granite and metasedimentary rocks in Peninsular Malaysia, have beenconsidered to be of poor aquifers. The map of shows the area underlain by hard rock as having poorto moderate potential for groundwater production (<230m3/well/day). This paper presents a finding ofproductive hard rock aquifers in the west coast of Peninsular Malaysia. Data from tubewell drillingscarried out for industrial water supply were analyzed. It was found that the hard rocks could yieldfresh water up to a maximum of 890m3/well/day. The wells were between 50 m and 200 m deep. Highdischarge rates of groundwater above 300m3/well/day were encountered from wells that penetrate majorfracture zones. The hard rocks are generally fractured at various depths. Groundwater in interconnectedfractures has a steady flow that sustains production during pumping tests and actual usage of the wells.This phenomenon indicates that the groundwater is being recharged by infiltration of rainwater throughthe overlying weathered rocks and soils. Tubewells in hardrock of West Coast of Peninsular Malaysiawere found to have an average discharge rates of 343m3/well/day. However, deep tubewells penetratedonly weathered granite, are generally non productive (<70m3/well/day). Limited fracture openings andrestricted recharge areas are likely to be the reason for the low discharge. Clay particles in fractureswere observed to be the factor for the low success rate and poor quality of the water particularly inmetasedimentary areas.

ISSN 0128-7680

e-ISSN 2231-8526

Article ID

JST-0284-2011

Download Full Article PDF

Share this article

Recent Articles