I see them as different axes. A service can be small, and it can be the only service. SOA means your larger service is comprised of smaller services, but says nothing about the size of those services.
An URL shortener is a micro service without SOA. A huge web application with four services that are half a million LOC each is SOA, but not micro services.
An URL shortener is a micro service without SOA. A huge web application with four services that are half a million LOC each is SOA, but not micro services.
I wonder what Martin Folwer has to say...