Origin of Kimberley zebra rocks

Ascertain the geological processes responsible for the formation of Kimberley zebra rocks—including whether the alternating hematite-rich and silica-rich bands and associated patterns arise from hydrothermal alteration, acid sulfate soil weathering, or liquid-crystal-like mineral ordering.

Background

Zebra rocks from the Kimberley region of Western Australia display highly regular banding and related spot and pillar patterns in fine-grained clay-rich siltstone. Several formation mechanisms have been proposed, including hydrothermal alteration, acid sulfate soil weathering, and liquid-crystal phase behavior.

The review explicitly states that the geological processes leading to these rocks are not known, underscoring the need to resolve among competing hypotheses.

References

Furthermore, the geological processes that led to the formation of these rocks are not known, although several have been proposed from their first description in 1925 .

— Self-Organized Pattern Formation in Geological Soft Matter (2412.18999 - Cartwright et al., 25 Dec 2024) in Subsection Zebra rock