It’s time to talk about fingerprint lakes. I’ve already discussed bifurcations, ridge endings, and minutiae, after all.
If you haven’t had the opportunity to read my prior three posts, suffice it to say that when ridges end or bifurcate (split in two), the point at which this happens is a minutia.
But what if a ridge bifurcates and immediately rejoins? Then you get a fingerprint lake, or enclosure.
No, not that kind of lake.
Now forensic friction ridge examiners don’t care whether the detail is a ridge ending, bifurcation, trifurcation, lake, or something else. (Well, they do.) They document what they see, and lakes (when clearly visible on both prints) are extremely helpful in identification.
But computerized automated fingerprint identification systems DO care. If the lake is only a puddle—perhaps a dot or short ridge depending on pixel/ridge width resolution—the AFIS may or may not assign minutiae. If the AFIS chooses to mark them, it will show two opposing bifurcations at either end of the lake.
But in conclusion, that’s a lake. Hope that helps. Perhaps I will explore additional friction ridge geography later.
