In Western Australia Gibb Maitland set up a geological survey, mining record office and public museum. He instituted a program of systematic mapping, and led from the field. In particular he paid attention to locating underground water sources, some bores between Geraldton and North West Cape still supplying water. He also predicted artesian water under the Nullarbor. Gibb Maitland spent several long periods in the Kimberleys and Pilbara, establishing stratigraphic order in the old rocks. By the time of his retirement more than half the state had been mapped at least in reconnaissance by members of the survey, who endured extraordinary conditions in the field.
Gibb Maitland edited The Mining Handbook of Western Australia (1919), but his major publications were his Summary of the Geology of Western Australia (also 1919) and three bulletins on the Pilbara. Also the WA Geological Survey, under his direction, produced significant reports on the Kalgoorlie, Coolgardie and Murchison goldfields, and the Collie coalfield.
The Gibb Maitland Medal is awarded by the Western Australia Division of the Geological Society of Australia in order to recognize individuals who have made substantial contributions to geoscience in Western Australia. The Gibb River (and Road) and the Maitland Range, and some invertebrate fossils are named for Gibb Maitland. The mineral known as maitlandite, named by E.S. Simpson, is now known to be thorogummite.
Maitland was lucky in his earliest days in W.A. to have Government support with the immediate appointment of two assistant geologists, but his talent for organisation and commitment to economic geology resulted in a very productive period for the Geological Survey.