Halfway through and have ground to a halt. Could do with a kickstart viz
S American native sweet and unsophisticated at the outset (4) A????
9 Across (7) local area hosting a team that has Brazilian roots? P??????
10 down Historic charter of university managed blunder; blame belonging to Fellow close to Provost (13) ??A?O???E???T
23 down (4) certain familiar old US rock band recalled Out of Time ???Z
Hi Lie-inking, many thanks - I had Alpine Hare for 1 down (mountain dweller's hot female mates. not married and I had Epeirogenesis for 21 across (records on kept about personnel - old info - a cause of major faults) I had taken this clue to refer to earthquakes! It accounted for the erroneous E in 10 down.