I have a master's degree in Geography and Urban Planning with mediocre GPA scores (15.5/20 or B). I graduated from a public university in the middle of nowhere that has a strict test system in which university professors cannot evaluate their students. A central assessment office introduces two to 5 books for each course at the beginning of each semester and a uniform strict exam (something like a national entrance exam) is carried out. I have never seen anyone obtain an A in this university.
I have published three ideas in prestigious peer-reviewed journals (for all of them I am the first and corresponding author). These contributions are significant. the problem is, they are important for various fields, not one. And none of them is closely related neither to Geography, nor Urban Planning. One of them solves a famous geometric calculation problem in computing cumulative viewshed of a large region. So it is related to GIScience. The other is to increase the spatial resolution of SAR data. Therefore, it is related to remote sensing. And another is a novel spatial regression model that eliminates aggregate errors. All of them solve problems that haven't been solved before. And I was nerdy enough to waste my time this way.
I want to further my studies (attend a Ph.D. position), preferably in one of the Nordic countries, in geography or urban planning but I do not think I am a good fit with the Frankenstein research background I have. Plus, my grades are not good too. The university I graduated from is not good either (it is ranked 350<400 worldwide). In most Nordic universities, the Ph.D. topics are pre-determined. Their topics are often popular concepts that are completely relevant to geography or urban planning.
Is my dream of getting a Ph.D. a mere fantasy with regard to these facts? If not, what a proper strategy could be?