So, the geological classification shapefile of the Philippines has the
'DESCRIPT' field which contains the geological time scale of each feature.
- "Oligocene-miocene" and "Oligocene-miocene (igneous Rocks)" and "Oligocene-miocene (sedimentary & Metamorphic Rocks)"
- "Paleocene(?)-eocene (igneous Rocks)" and "Paleocene-eocene (sedimentary & Metamorphic Rocks)"
- "Undifferentiated" and "Undifferentiated (igneous Rocks)"
However, some attributes have varying but same time scale.
How could the "same" time scales categorized by creating another field which contains the category?
Categorizing the features by spotting if a keyword is in the feature or specifying the exact name of the feature.