On the hydrology of the bauxite oases, Cape York Peninsula, Australia

Leblanc, M., Tweed, S., Lyon, B.J., Bailey, J., Franklin, C.E., Harrington, G., and Suckow, A. (2015) On the hydrology of the bauxite oases, Cape York Peninsula, Australia. Journal of Hydrology, 528. pp. 668-682.

[img] PDF (Published Version) - Published Version
Restricted to Repository staff only

View at Publisher Website: http://dx.doi.org/10.1016/j.jhydrol.2015...
 
11
3


Abstract

One of the world's largest bauxite deposits is located in the Cape York Peninsula, North-East Australia. Little is known about the hydrology of these remote bauxite deposits. Here, we present results from a multidisciplinary study that used remote sensing, hydrochemistry, and hydrodynamics to analyse the occurrence of several large oases in connection with the bauxite plateaus. Across this vast region, otherwise dominated by savannah, these oases are sustained by permanent springs and support rich and diverse new sub-ecosystems (spring forests) of high cultural values to the local indigenous population. The spring water chemistry reveals a well-mixed system with minor inter-spring variation; TDS values of spring waters are low (27–72 mg L−1), major ion compositions are homogenous (Na–Si–DIC–Cl) and δ18O and δ2H values are reflective of rainwater origin with little evaporation prior to recharge. Dating of spring waters with anthropogenic trace gases (CFC-12 and SF6) indicates mean groundwater residence times ranging from <1 to 30 years. An artificial tracing experiment highlighted the existence of a flow pathway from the bauxite land surface to the sandy aquifer that feeds the springs through discontinuities in the ferricrete layer. In addition, the soil infiltrability tests showed the bauxite land surface has very high infiltrability (15 mm min−1), about four times greater than other adjacent land surfaces. Across the lower part of the Wenlock Basin, satellite data indicate a total number of 57 oases consistently located on the edge of the bauxite plateaus. This super-group of permanent hillslope springs and their ecosystems adds another important attribute to the list of natural and cultural values of the Cape York Peninsula.

Item ID: 41857
Item Type: Article (Research - C1)
ISSN: 0022-1694
Keywords: bauxite; springs; ecohydrology; remote sensing; hydrogeochemistry; groundwater dating
Date Deposited: 08 Dec 2015 14:13
FoR Codes: 04 EARTH SCIENCES > 0406 Physical Geography and Environmental Geoscience > 040603 Hydrogeology @ 100%
SEO Codes: 96 ENVIRONMENT > 9609 Land and Water Management > 960908 Mining Land and Water Management @ 100%
Downloads: Total: 3
More Statistics

Actions (Repository Staff Only)

Item Control Page Item Control Page