Territory Stories

Development of a Groundwater Model for the Western Davenport Plains

Details:

Title

Development of a Groundwater Model for the Western Davenport Plains

Creator

Knapton, Anthony; CloudGMS Pty Ltd

Commissioned by

Northern Territory. Department of Environment, Parks and Water Security

Collection

E-Publications; E-Books; PublicationNT; WRD Technical Report 27/2017

Date

2018-03

Location

Western Davenport Water Control District

Abstract

CloudGMS has been commissioned by DENR to develop a numerical groundwater model of the aquifers within the central area of the WDWCD to improve confidence in the sustainability of the groundwater resources, as this is the area within the WCD with greatest potential for intensive development.

Notes

Made available by via Publications (Legal Deposit) Act 2004 (NT); Prepared for Dept Environment and Natural resources

Table of contents

Executive summary -- 1 Background -- 2 Physical -- 3 Available data -- 4 Conceptual model -- 5 Model design & construction -- 6 Parameter estimation -- 7 Water balances -- 8 Sensitivity analysis -- 9 Predictive scenarios -- 10 Conclusions -- 11 Reference -- 12 Document history and version control -- Appendix A - Groundwater level hydrographs - Appendix B - Alek range horticultural farm sub-regional modelling

Language

English

Subject

Groundwater; Northern Territory; Western Davenport Water Control District; Conceptual mode

Publisher name

Northern Territory Governmnet

Place of publication

Palmerston

Edition

version 2.0

Series

WRD Technical Report 27/2017

Format

ix, 127 pages : colour illustration and maps ; 30 cm

File type

application/pdf

ISBN

9781743502976

Use

Attribution International 4.0 (CC BY 4.0)

Copyright owner

Northern Territory Government

License

https://creativecommons.org/licenses/by/4.0/

Related links

https://hdl.handle.net/10070/842058 [LANT E-Publications: Development of a Groundwater Model for the Western Davenport Plains, version 1.1]

Parent handle

https://hdl.handle.net/10070/858845

Citation address

https://hdl.handle.net/10070/858846

Page content

Western Davenport WCD Groundwater Model (v2.0) Available Data CloudGMS 22 3.4.6. Ordivician Hanson River Beds (Oh) Four lithological units were identified in Hanson River Beds by Kennewell and Huleatt (1980), where a very detailed description of their lithology is included. Sandstone, fine to coarse grained, generally poorly sorted and angular, but well sorted and rounded in parts, very silicified in parts; siltstone, generally light green where fresh but weathers brown, sandy or clayey in parts, micaceous, fissile, minor glauconite in parts; dolomite, medium crystalline, white, light brown, yellow, red-brown, or black; dolomite, finely crystalline, white, chalcedonic in parts; coarse grained dolarenite: marine and possibly fluvial. The upper 10 m of the Hanson River Beds are red-brown in BMR Lander River 1, suggesting weathering below the contact. Thickness may be up to 800 metres in the Lander Trough (Kennewell & Huleatt, 1980). 3.4.7. Devonian Dulcie Sandstone (Dud) The Dulcie Sandstone occurs in the south-eastern portion of the WDWCD and disconformably overlies the Tomahawk beds. No overlying unit is exposed, it being the youngest formation of the Georgina Basin. The Dulcie Sandstone consists of strongly cross-bedded, well-sorted, fine- to medium-grained, medium- to very thick-bedded quartzarenite. The arenite contains minor tourmaline, muscovite, kaolinite and oxides. The formation shows very little lithological variation although very thin coarsegrained gritty intervals have been observed at the base of some cross-bed sets. Individual cross-bed sets range up to four metres in thickness with moderate to high angle forsets displaying divergent dip directions and common avalanche structures. 3.4.8. Devonian Lake Surprise Sandstone (Pzl) Devonian aged Lake Surprise Sandstone occurs in the north-eastern portion of the WDWCD and is lithologically very similar to Dulcie Sandstone. The Lake Surprise Sandstone unconformably overlies the Hanson River beds capping the Wiso Basin sequence. The formation is confined to the Lander Trough and consists of feldspathic clayey sandstone, white, grading to dark brown if ferruginised, very fine to medium grained, subangular to moderately well rounded, commonly bimodally sorted with silt and clay matrix in parts and altered feldspar grains are common, silicified and/or ferruginised in some outcrops, generally cross bedded, low angle cross bedding common, slight to extreme slumping in some outcrops. The Lake Surprise Sandstone is mostly flat lying with a maximum thickness of approximately 350 m and is interpreted to have been deposited in a shallow marine or beach environment (Wyche & Simons, 1987). 3.4.9. Cenozoic sediments Quaternary deposits are typically thin and are probably less than 10 metres thick and are dominated by a blanket of red aeolian sand (Dodson & Gardener, 1978). Twelve Cenozoic units have been mapped in the area. The distributions of three of them are of particular interest to this study. Alluvial deposits (Qa) occur in active channels and floodplains such as Taylor Creek, Wycliffe Creek and Skinner Creek. Aeolian sand (Qs) is ubiquitous throughout most of the interior of Australia. In the Western Davenport area, a widespread blanket of unconsolidated late Quaternary aeolian sand mantles large sections of the lowland surfaces. These sands are typically fine to medium grained and