Patterns in Fingerprints

Fingerprint patterns fall under 3 general groups:

Arches

In arches the ridges go across the finger but don’t make backward turns.

The two types of arches are: plain arches and tented arches.

Plain Arch

• Tented arches- will have an angle, an up thrust, or will have two out of three basic characteristics of the loop.

Tented Arch



Loops

Occur in approximately 60-70% of fingerprint patterns.

In Loops one or more of the ridges enter on either side of the impression, will re-curve, touch or cross the line running from the delta to the core and then cease existing on or in the direction of the side where the ridge/ridges had originally entered. Every single loop pattern has one delta, one core and always has a ridge count. There are also two types of loops, radial and Ulnar loops.



Radial Loop



·         Radial loops- not very common, runs in the direction of the thumb.

Ulnar Loop

 ·         Ulnar loops- same side as the little finger, runs in the direction of the little finger.

Whorls

In a whorl some of the ridges in the fingerprint will make a turn through at least one circuit. If a fingerprint pattern contains two or more deltas it will be a whorl pattern. The four types of whorl patters are: Plain whorl, central pocket loop whorl, double loop whorl, and the accidental whorl.

·         Plain whorl- consists out of one or more ridges that make or will make a complete circuit with two deltas.  Between these two deltas an imaginary line is drawn and at least one re-curving ridge within the inner pattern area is either cut or touched.

Plain Whorl

·         Central pocket loop whorl- these consist out of at least one re-curving ridge or will have an obstruction at right angles to the line of flow, with two deltas, between the two deltas there will be no re-curving ridge within the pattern that is cut or touched.  These whorls will make one complete circuit that may be a spiral, oval, circular or any other variant of a circle.

Centarl Pocket Loop Whorl

·         Double loop whorl- consists out of two separate and distinct loop formations that have two separate and distinct shoulders for each core. They will also have two deltas and one or more ridges, these will thus make a complete circuit.

Double Loop Whorl

·         Accidental whorl- these whorls consist out of two different types of patterns(with the exception of the plain arch), they will have two or more deltas, or will have a pattern that possesses some of the requirements for two or more different types, or a pattern that will conform to none of the definitions.

Accidental Whorl

Plain arches- have an even flow of ridges from one side to the other.