ERTH3104 Virtual Field Trip to New England Orogen
Stop name: Flynns Beach
Location: North of the Flynns Beach (Port Macquarie) along the coast. Need to watch out for tides - outcrops are best accessible when the tide is low.
Coordinates: 31°26'13.51"S, 152°55'31.97"E
What to see: Following what we see at the Lighthouse Beach, at Flynns Beach you will see a more diverse range of blocks within this melange. Large blocks of pillow basalt (blocks of tens of metres in size), chert, high-pressure metamorphic rocks.
Additional Data:
A petrographic thin-section of blueschist/eclogite taken from the Flynns Beach (PM-01 at Thin section collection).
Zircon U-Pb geochronologic results from an eclogite sample (Click to download the Excel data file). Hints on what to do: calculate a concordant age and/or a weighted mean age with IsoplotR and preliminarily discuss what this age means.
(Above) Pillow basalt (photo taken facing south). (Photo by R. Zhou)
(Above) Pillow basalt. Could you tell the original upside direction? (Photo by C. Fu)
(Above) Pillow basalt (surface morphology). (Photo by C. Fu)
(Above) Hydrothermal red chert (called ‘Jasper‘) infilling between pillows. Would you expect to find any radiolarians in these cherts? (Photo by C. Fu)
(Above) Serpentinite matrix melange with smaller blocks. Blocks are mostly serpentinized ultramafic rocks.
(Above) Serpentinite matrix melange with smaller blocks. Blocks are mostly serpentinized ultramafic rocks.
(Above) A gabbro block in the melange. (Photo by Y. Chen)
(Above) A chert block in the melange. (Photo by Y. Chen)
(Above) A chert block (an isoclinal fold) in the melange. (Photo by R. Zhou)
Melange matrix
Folded chert block within this melange
Minor fault plane coated with secondary minerals (slickenline)
(Photo by R. Zhou)
Minor fault plane coated with secondary minerals (slickenline)
(Photo by R. Zhou)
(Above) 3D model for the eclogite outcrop. This is a block within this melange. Additonal data (thin section PM-01 and zircon U-Pb ages) are from this outcrop.
(Above two models) 3D outcrop scans at the Flynns Beach showing the blueschist block.
There is a geological walk developed along the coast of Port Macquarie. Check it out next time you’re there! Here is a guide.