The increase was a mere 0.4%, or A$2.2 million, to $554.4 million.
The largest contributor to the increase in the trend estimate this quarter was Western Australia, up 0.6%.
The current quarter estimate is 16.1% higher than the December quarter 2017 estimate.
The seasonally adjusted estimate for mineral exploration expenditure also rose 0.4% to $549.4 million in the December quarter, with the largest contributor being the Northern Territory, up 16.8%.
In original terms, mineral exploration expenditure fell 0.3% to $582.8 million in the December quarter.
Gold attracted the largest proportion of expenditure, at $243 million, followed by base metals ($148.9 million).
Exploration on areas of new deposits rose 4.5% and expenditure on areas of existing deposits fell 3.3%.
In original terms, the largest decrease by minerals sought came from expenditure on iron ore, which was down 12.5%. That may change in the next set of figures, due out in June, as a result of higher prices in the wake of Vale's tailings dam collapse.
The trend estimate for metres drilled rose 0.8% in the December quarter, while the current quarter estimate is 16.5% higher than the December quarter 2017 estimate.
The seasonally adjusted estimate for metres drilled fell 4.9%, while in original terms, metres drilled fell 10.7%.
Drilling in areas of new deposits fell 8.9% and drilling in areas of existing deposits fell 12.3%.
The Minerals Council of Australia said the latest statistics "confirms Australia as world-leading resources destination, creating highly-paid, highly-skilled jobs which sustain and strengthen regional communities".
