News Microfossils from the earliest land plants provide clues about Australias petroleum potential

Microfossils derived from the earliest land plants and extinct marine groups have been recovered from 42 samples taken from the Barnicarndy 1 well, drilled in partnership with the Geological Survey of Western Australia in the onshore Canning Basin in Western Australia.

The fossils were found as part of Geoscience Australias Exploring for the Future program work in the Barnicarndy Graben, which aimed to understand the history of the sedimentary fill and hydrocarbon prospectivity of the underexplored southern Canning Basin.

Geoscience Australias Branch Head of Basin Systems David Robinson said the study uncovered evidence of some of the Earths oldest land plants.

The team set out to find and compare microfossils in the Barnicarndy 1 well to better understand the resource potential of the area, Dr Robinson said.

Incredibly, the microfossils we found are estimated to be about 482 million years old. The fossils include extinct micro-organisms such as acritarchs, probable cyanobacteria and cryptospores.

Of importance is the identification of cryptospores, the fossilised remains of early land plants which document the emergence of plants onto wetlands in the Early Ordovician Period (about 475 to 482 million years ago). These land plant spores are the oldest weve found in Australia and mark the initial colonisation of the Earths land surface by plants.