Geography
The Mid West Region of Western Australia extends along the west coast from Green Head to Kalbarri and more than 800km inland to Wiluna in the Gibson Desert. Its area of 468,712km² covers nearly one fifth of the State, comprising 17 local government authorities. The City of Greater Geraldton is the region's commercial, administrative and service centre. The diversity of natural resources in the Mid West has resulted in a wide range of land uses and a broad economic base.
Population distribution and density is related to the intensity of land use. The higher rainfall areas closer to the coast tend to support more intensive agricultural land uses including horticulture and mixed cop/livestock farming. The smaller farms result in relatively higher rural populations, which support larger, more closely spaced service centres. As intensity of land use decreases into pastoral and mining areas, local populations decline markedly.
The Mid West includes a diversity of geographic features. Ranges include the flat topped Moresby Ranges near Geraldton, the Weld, Nicholas, Dividing, Montague, and Robinson ranges. However, these are minor and with a few other exceptions including the dissected Northampton Block and small areas of breakaway country, the region tends to be relatively flat. Apart from these `outcrops', the most prominent landform features in the region are the river valleys formed by the Greenough, Chapman and Irwin rivers and the spectacular gorges carved by the Murchison River in the sedimentary rock layers near Kalbarri. In eastern parts of the region, the absence of external river systems has resulted in the formation of numerous salt lakes.
The coastal areas experience a mild Mediterranean climate with hot/dry summers and cool/wet winters. Inland areas are subject to an arid climate with very hot/dry summers and cold/dry winters.
The relatively low rainfall of the region makes groundwater resources extremely valuable. Generally, groundwater is available throughout the region with southern coastal areas having access to higher yields and quality. The quality and quantity of groundwater in inland areas and other areas such as the Northampton Block varies.
Soils in the agricultural zone tend to be mainly sands on the plains with more fertile loam valleys.
The sandplain soils require higher inputs of fertilisers (including trace elements) to be productive. Much of the pastoral area accommodates shallow loams and deep sands. With adequate water some of these soils have been able to support commercial horticultural activities.
Source: Mid West Geographic Perspectives