Welcome to Rootschat, and to the Armed Forces board...

I reckon that this chap is Royal Marine Light Infantry from betwixt 1878 and 1902...As he has a Glengarry, we can narrow down a little to 1878-1897
I can't make out the helmet plate too well, but the Glengarry double badge thing may well confirm...
As the wording around the belt buckle, and the apparent Globe and Laurel on his epualletes may also confirm...
I think the buckle has "Gibraltar" and "Per Mare Per Terram"...