MAP 21 − HYDROGEOLOGICAL INVENTORY Tasmania ENERGY and RESOURCES DEPARTMENT of INFRASTRUCTURE
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MINERAL RESOURCES TASMANIA MUNICIPAL PLANNING INFORMATION SERIES TASMANIAN GEOLOGICAL SURVEY MINERAL RESOURCES TASMANIA MAP 21 − HYDROGEOLOGICAL INVENTORY Tasmania ENERGY and RESOURCES DEPARTMENT of INFRASTRUCTURE 300 B a 2 y 0 1 0 200 00 WAY GH HI Pt Home Lookout Prosser Bay Orford River Ile du 300 Nord 00 2 Quarry Pt Shelly Beach CAPE BOULLANGER River 10 0 Spring Fossil Bay Beach MAN 20 TAS 0 3 100 0 4 0 100 00 0 30 Buckland Johnsons Pt 200 TIER 200 SH FLA MT 6 MARIA00 500 300 100 Carrickfergus GE MARIA A 4 00 1 S 00 200 100 Bay S A P ISLAND Booming 2 00 200 Bay Sandspit Pt MISTAKEN CAPE Pt 50 Lesueur 0 3 300 Little Raggedy 00 PROSSERS Shoal Cape des Head 300 SUGARLOAF Riedle Tombeaux 200 Bay Pt des Galets Bay ay B 700 300 30 0 400 Y 4 R ster 00 y Cockle Bay U O 4 00 C 20 0 GLA 400 MORGAN / SPRI 300 NGBAY Nugent 400 MER SORELL Cape Bald 300 Green 40 Bluff 0 200 CAPE MAUROUARD 400 300 CAPE BERNIER Barren 00 4 Head 0 10 200 00 300 00 3 2 100 Hellfire Bluff CAPE PERON 200 Pt du Ressac Wattle 0 Hill 10 3 00 300 300 100 Kellevie er iv R MARION ARTHU R 300 100 BAY 0 200 Forcett 300 10 200 100 100 HIGH WAY Copping Lewisham 100 on lt Car A 2 00 E CAPE PAUL 200 LAMANON S 200 Dodges y Ferry Ba Park North Beach CAPE FREDERICK Carlton 300 100 Bay HENDRICK 100 an Connellys Carlton Marsh Blackm Bluff Dodges Primrose 00 Bangor Pt Sands 1 Dunalley Ferry SORELL TAS Park MAN Beach Primrose Point Fulham Dunalley MT 2 Carlton Point 00 Bay FORESTIER 200 300 HIGH ARTH 200 YELLOW 0 U 200 40 R BLUFF Green Head 100 Sloping Smooth Island Island Lime FORESTIER 200 300 Sound Murdunna Bay CAPE SURVILLE George PENINSULA King 400 RANGE Lobster Point Monk Bay Ironstone 100 Point 400 HI YS G L H R WAY 500 0 20 FAZACKE Flinders Bay NORFOLK 200 0 BAY 10 100 Deer Pt Saltwater Eaglehawk Bay Eaglehawk Neck River Dart Is. Pirates Halfway Bay Prices Bluff Penzance Bay 20 Doo 0 0 100 10 Town 10 Cascades 0 2 Bay 00 Taranna 200 Premaydena N Waterfall Bay 300 Koonya 40 0 0 200 0 1 200 500 HIGHWAY OUTER 20 00 2 NORTH 0 HEAD TATNELLS S M A HILL O'Hara Bluff A 0 10 Roaring Beach 100 T Bay 300 0 Nubeena 40 WEDGE TASMAN Oakwood Thumbs Pt UR BAY 00 4 PENINSULA TH 0 10 AR 0 NU 20 BEENA 0 Hippolyte 20 Dolomieu Pt Rocks Wedge 200 Fortescue Island Bay ROA D PORT CAPE HAUY Port Highcroft Arthur 200 ARTHU Two Island 00 4 300 Bay R 2 00 00 2 0 40 0 30 400 Stormlea 100 1 00 Curio Bay MUNRO 300 Budget Head BIGHT Salters Pt MT RAOUL Haines West Arthur Bight 0 Head 0 0 300 40 3 Black Head Raoul 0 20 CAPE PILLAR Bay MAINGON BAY 200 Tasman Island CAPE RAOUL Scale: 1:100000 MEAN ANNUAL RAINFALL 0 2 4 6 8 10km Feature type Yield 11 and accuracy Salinity − TDS AGD66 − AMG Zone 55 PROSPECTIVITY VULNERABILITY TO POLLUTION Contour Interval: 100 metres These maps are complimentary to the 1:250 000 scale hydrogeological maps which use as a basis, a compiled 1:250 000 scale geology layer (derived from 1:25 000, 1:50 000, 1:63 360 scale AQUIFER TYPE (Whole of Tasmania) ROCK GROUPS geological maps together with some areas where only reconnaissance mapping is available). These 1:100 000 scale maps are easier to read and use the regional groundwater prospectivity 17 boundaries from the 1:250 000 scale maps as background information in the absence of more detailed uniform hydrogeological coverage across the whole State. They should be used in Borehole location accuracy Borehole location accuracy conjunction with the 1:250 000 scale maps and other more detailed hydrogeological maps and site specific reports, if available, as a preliminary to more intensive groundwater studies in a Quaternary aeolian deposits marginal to the coast High. 1 − 500 metres 500 − 2000 metres particular area. If additional projects are undertaken in targeted prioritised areas of the State, these maps can be further developed and made more site specific. consisting of fine to medium grain size sand. POROUS Spear point location accuracy Spear point location accuracy Boreholes shown on the map are those with locations mainly supplied by drillers and from location in the field by MRT staff. There are many spear bores installed for investigation and production (INTERGRANULAR) HIGH 1 − 500 metres 500 − 2000 metres 16 purposes in coastal sand deposits in Tasmania that may not be shown on these maps at this stage. Boreholes with yields >0.03 L/s have been considered as successful bores. Outputs of bores Well, dug well location accuracy Well, dug well location accuracy are those supplied by drillers and are mostly the result of short term pumping measurements. Some bores have been successful but outputs have not been reported. Boreholes reported as dry 1 − 500 metres 500 − 2000 metres holes ususally have a small unreported yield (<0.05 L/s). Quaternary coastal plain deposits consisting of sand, Moderate to high. 21 Small elevated areas of any hydrogeological unit will usually have lower prospectivity because of limited storage and high drainage rates. In areas where there is little or no water bore data (e.g. POROUS MODERATE − clayey sand, shelly deposits and gravel underlying Depends on permeability of the material Southwest Tasmania), the groundwater prospectivity has been assumed to be similar to that in the areas where data are widely available. In areas of low rainfall, water quality can be poorer and (INTERGRANULAR) HIGH areas near the coast. that overlies the aquifer. water usage may be limited. Probable marine origin. These maps provide some additional information to the 1:250 000 scale hydrogeological maps in that there are some subdivisions of Permian and Triassic age units. There is some difference in hydrogeological properties and prospectivity between these units. For example the Upper Triassic lithic sandstone, mudstone and coal measures has lower prospectivity and poorer quality Unknown groundwater than the Lower Triassic and Permian rocks in most locations. The three dimensional shade effect enables users to understand the spatial relationship between adjoining Quaternary alluvium (clay, sand and gravel with varying Low to high. 0 (Dry) 20 hydrogeological units shown on the map and in some cases their relative thickness. POROUS LOW − clay content) and talus (boulder deposits). Low where clay material overlies aquifer. There is usually a degree of vertical stratification in the groundwater quality within the aquifers and results presented represent a composite value of salinity from drill holes at a particular time. (INTERGRANULAR) MODERATE Sand, gravel and mud of alluvial, lacustrine and littoral High where there is no clay. <= 0.05 Limited use for domestic and stock Natural groundwater quality is influenced by annual rainfall and the evaporation (e.g. high rainfall, low evaporation areas tend to have better quality groundwater then low rainfall, high evaporation origin. 0.05 − 0.5 areas), the composition of the rock types through which the groundwater passes and is stored in and by physical properties of the rocks such as permeability and porosity. Human activities such Minor windblown sands on sloping bedrock. as extensive groundwater pumping, pollution from various waste disposal activities and use of chemicals (agriculture, forestry, industry etc.) also may have negative effects on groundwater quality. 0.5 − 1.5 The geology (including aquifer prospectivity), geomorphology and the inter−relation between surface water, groundwater and rainfall in a particular area are important considerations in resource and Tertiary sediments: clay, sand and gravel of non marine Low to high. 1.5 − 5.0 Low where clay overlies aquifers. other groundwater/surface water studies. The attached average rainfall map can be used to make some general deductions about the possible links between the above−mentioned water balance POROUS LOW − HIGH origin (lacustrine alluvial deposits). Minor limestone factors. Climate has an affect on quantity and quality of both groundwater and surface water, as base flow in streams and spring water is largely, if not all groundwater derived under most conditions. (INTERGRANULAR) (marine origin). Variable thickness up to several hundred High where gravel aquifers come to the 5.0 − 10.0 In areas with unconfined shallow aquifers groundwater pumping near the rivers may result in the reverse water flow from the river towards the groundwater and result in decreased river flow. These metres. surface. maps provide preliminary information for more detailed groundwater and surface water studies. (High in NW The rainfall map shows the mean annual rainfall over Tasmania for the standard 30−year period from 1961 Moderate − high in NE > 10.0 to 1990. It was derived by the Climate and Consultancy Section in the Tasmania and Antarctica Regional Low − high in SE) Office of the Bureau of Meteorology, from a gridded analysis prepared by the Bureau’s National Climate Centre. The analysis system blends measured rainfall with topography to give estimates of rainfall for High − unless a layer of low permeability each area. The results will be less accurate in mountainous or data−sparse regions, and may differ FRACTURED ROCK Triassic, quartzose and lithic sandstones, mudstone, from the observations at individual locations. minor coal. Terrestrial origin (R, Rv, Rq). material overlies the aquifer. (Intergranular on HIGH some horizons) INDEX TO ADJOINING MAP SHEETS Permian mudstone, siltstone and sandstone (often pebbly), minor limestone, conglomerate and tillite.