This rhyodacitic dyke crops out in the Halls Creek vicinity between Bendemeer and Manilla in New South Wales. It is near vertically dipping, with a strike of ~120° and a strike length of at least 10 kilometres. Thickness varies from ~one up to several metres. Petrologically, it is thought to be related to the nearby Attunga Creek Monzogranite, a member of the Moonbi Plutonic Suite. At this locality near the western end of its extent, it is seen to intrude interbedded cherts and siliceous siltstones of the Woolomin Beds.
Internally, the structure of the dyke is largely massive, but at this location it displays prominent flow banding parallel to the intrusive contact. Additonally, there appears to be at least two pulses of intrusion, and flow banding in the central section of the dyke has been deformed into an asymmetric fold structure, indicating that sinistral shear affected the intrusion while it was still partly molten. The structure is reminiscent of soft sediment deformation. Updated 15/12/2021
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