The 36-year-old, who joined the Mariners in September, has been an ever-present under Paul Hurst and current boss Marcus Bignot.
The former Premier League defender has helped to shore-up the Town defence since his arrival, helping the Mariners to seven clean sheets in 15 games played.
Speaking about the move, the player said: "I’ve signed until the end of the season with talks about next season as well at the minute.
“I am happy – I have been enjoying my football here.
“I’ve played nearly every game and I feel that I have done well.
“It’s just nice to be out there, playing football and enjoying it at my age.”