The Sphinx itself has erosion, not just the enclosure. If it were just the enclosure with vertical erosion then maybe it could be connected but its not. The only way this channel could be connected to the vertical erosion channels on the Sphinx itself is if they had somehow fashioned a pump and giant shower head to spray it from above.
What about the horizontal erosion?
The only way this channel could be connected to the vertical erosion channels on the Sphinx itself is if they had somehow fashioned a pump and giant shower head to spray it from above.
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Explanation is that there was silt build-up around the Sphinx, and the silt was dredged out vertically over hundreds of years leaving the vertical erosion. There were numerous yearly religious ceremonies which involved a boat going around the monument so the silt had to be removed.
R.Temple 2009 “The Sphinx Mystery”.