Dunkheld Quarry, Bathurst, NSW
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This is a columnar jointed Dyke 1. This dyke is of virtually the same composition as the basalt that it has intruded and this
dyke and the 2 other dykes that were identified were derived from the cooling basalt lava and likely injected in the late stage of the
cooling of the basalt flow.
It is slighly more silicic as indicated by its lighter colour. Note that columns are formed perpendicular to a cooling surface
so that you can see that the side of the dyke was a cooling surface, indicatuing that this blocky part of the flow was hard and cool when this dyke was intruded. |
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