Fingerprint Patterns Flashcards
Arch - Plain
A fingerpint pattern in which the friction ridges enter on one side of the impression and flow, or tend to flow, out the other side with a rise or wave in the centre.
Arch - Tented
A type of fingerprint pattern that possesses either an angle, an upthrust, or two of the three basic characteristics of the loop.
Core
The approximate centre of a pattern.
Delta
The point on a friction ridge at or nearest to the point of divergence of two types lines, and located at or directly in front of the point of divergence (SWGFAST).
(Triradius) Area on the friction ridges where three ridge systems meet (Ashbaugh)
Loop - Ulnar
A type of pattern in which one or more friction ridges enter upon either side, recurves, touch or pass an imaginary line between delta and core and flow out or tend to flow out, on the same side of the friction ridges entered. The flow of the pattern runs in the direction of the ulna bone of the forearm (toward little finger).
Loop- Radial
A type of pattern in which one or more friction ridges enter upon either side, recurves, touch or pass an imaginary line between delta and core and flow out or tend to flow out, on the same side of the friction ridges entered. The flow of the pattern runs in the direction of the radial bone of the forearm (toward thumb finger).
Whorl - Accidental
With the exception of the plain arch, a fingerprint pattern consisting of two different types of patterns with two or more delta. A pattern that possesses some of the requirements for two or more different types. A pattern that conforms to none of the definitions.
Whorl - Central Pocket Loop
A type of fingerprint pattern that has two deltas and at least one friction ridge which makes, or tends to make, one complete circuit, which may be spiral, oval, circular, or any variant of a circle. An imaginary line drawn between the two deltas must not touch or cross any recurving friction ridges within the inner pattern area.
Whorl - Double Loop
A type fingerprint pattern that consists of two separate loop formations with two separate and distinct sets of shoulders and two deltas.
Whorl - Plain
A type o fingerprint pattern that consists of one or more friction ridges which make, or tends to make, a complete circuit, with two deltas, between which, when an imaginary line is drawn, at least one recurving friction ridge within the inner pattern area is cut or touched.
