I have the following image of metasedimentary outcrop from a Proterozoic continental rift-fill sequence:

enter image description here

The middle layer has a pelitic composition and contains abundant cordierite porphyroblasts (visible as weathered depressions). The layers above and below this layer are more psammitic. The lower layer appears to display inclined cross bedding, whereas the top layer seems to be more massive. I suspect that this outcrop preserves a 'fining upwards' sequence with the psammitic layers representing the coarser (high-energy) deposition and the cordierite-rich layer representing a finer (low-energy) depositional phase.

What I'm not sure of is which way this outcrop is younging. Are the cross bedded layers deposited on top of the pelitic layer (i.e. the image is 'upside-down')?

Or, was the pelitic layer deposited on top of the lower layer cross beds?


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