Can i do a phd in UK ? i have a msc(1st class) + 3rd class BSc degree

I will be getting a 1st class MSc in Engineering Geology from a Sri Lankan university soon (one of the top unis in the country and i consider myself extreamly lucky for getting selected for the course after a getting a 3rd for my BSc) but I made a mess during my BSc and got only a 3rd class..i did my BSc (Geology) in England (bristol)..Prior to that I managed to get 3A's and a B for ALs and 9A s for GCSE

+ these i have one year experience in working as a Geologist in Sri Lanka

However i am so concerened about the 3rd class degree i got and I feel that its going to prevent me from having a good career in any developed country..What are my possibilities ? Can I do a PHD in UK/USA/Aus with my qualifications ? Will that make up for my 3rd class BSc degree when it comes to employment ?