My oak floor is 15 years old and I believe it may have been installed with no expansion gaps at the edges. There is one area where the floor is noticeably higher than the surrounding floor and there are creaks in some floor areas. It is installed over OSB and floor joists below. It is 2.5 inch tongue and groove planks.

I'm assuming this was kiln dried oak and would naturally expand over time. Is this kind of buckling normally caused by this situation? Is there a fix other than removal and reinstall?

Buckling happens after extreme cupping, where the flooring becomes detached from the floor. A loose spot or squeaks or crackling doesn't mean it has buckled. Kiln drying to the correct moisture content of wood acclimated to ambient conditions will absorb and release moisture without changing dimension. If the flooring was dried below the moisture content of acclimation it can expand a certain percentage for each board, on average. This is the reason for acclimating to each job site. A responsible installer will have an idea of the targeted moisture content for the floor to meet conditions without too much expansion or shrinkage. There is a range of moisture content in flooring where the installation will be acceptable over time. The flooring can be "tight" or "loose" depending on the humidity during the year.
I hope your floor has not completely failed. If it has buckled it would be time to take almost all of it up and lay the floor over again. You could use the same flooring after de-nailing. It would be acclimated to the work site.