You had a 50GRC UTXO which staked and you earned a 10GRC block reward and 1.02000124GRC in research rewards. The transaction always looks like this. The original utxo is deducted so that the new utxo with the additional GRC can be created all as one. The was no nefarious anything going on, but the raw staking transaction info can be a bit cryptic if you aren't used to seeing it.