|Hawkesbury sandstone, Fairlight Sydney, showing bedding,|
cross-bedding and vertical joints.
The sand that would become this sandstone was laid down in a time when plants were ferns, reptiles were becoming dinosaurs, and mammals were only just being thought about. True, there are some remnants of more recent volcanoes around, but almost everything that you can see is good old-fashioned sedimentary rock, lying in almost horizontal layers.
|The heat of the lava 'baked' the sandstone, changing it to|
quartzite. This is called contact metamorphism.
, but the shale lenses and volcanic rocks are very much the exception, and Sydney is Sandstone City.
|Sundew, Drosera spatulata.|