I need some terminology help as I am still learning GIS.

I have two datasets. One with the address of every fire and it's latitude/longitude of small census tract. One with the location of every parcel of land (property) within that census tract. I need to join or match the two datasets so I end up with a map of every property that has ever had a fire and a list of the properties without ever having a fire. I thought it might be similar nearest neighbor or involve R-trees. However, every time I look for a way of doing this I run into methods of "matching point within the same dataset" not what I need. I have to use two different datasets.

What exactly is this type of matching or joining between nearest lat/long of different datasets called in GIS terminology?

To help answer this question let me show two different dataset with slightly different situations: (It took me a minute of searching to find these polygons) First is the my actual GA data. This data is only of 3 months:

Dekalb GA County Fires

In it, every green point is a building fire, while every brown shape is a building. About 95%-98% of the data overlays a parcel, so I think is a point in polygon overlay.


Assuming that your fire addresses are point locations and that your properties are polygons, this sounds like a point-in-polygon overlay analysis.

Tools for doing this typically have names like intersect or spatial join.

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