Questions and Answers
What is the angle of impact?
What does the area of convergence indicate?
The location of the blood source in two dimensions.
What is an area of origin?
The three-dimensional location from which spatter originated.
What is arterial spray?
Signup and view all the answers
Define back spatter.
Signup and view all the answers
What creates a cast-off pattern?
Signup and view all the answers
What does crime scene reconstruction involve?
Signup and view all the answers
What is a drip trail pattern?
Signup and view all the answers
What is an expirated blood pattern?
Signup and view all the answers
What causes a flow pattern?
Signup and view all the answers
Define forward spatter.
Signup and view all the answers
What is considered high velocity spatter?
Signup and view all the answers
Characterize impact spatter.
Signup and view all the answers
Define low velocity spatter.
Signup and view all the answers
What does medium velocity spatter refer to?
Signup and view all the answers
What is satellite spatter?
Signup and view all the answers
What does skeletonization mean in blood spatter analysis?
Signup and view all the answers
What is a transfer pattern?
Signup and view all the answers
Define void in the context of blood spatter.
Signup and view all the answers
Which are sources of blood spatter? (Select all that apply)
Signup and view all the answers
What type of spatter pattern does a gunshot produce?
Signup and view all the answers
What is meant by documenting bloodstain evidence?
Signup and view all the answers
Two techniques for documenting bloodstain evidence are the ______ method and the ______ method.
Signup and view all the answers
What do general bloodstain features indicate?
Signup and view all the answers
What can pattern interpretation uncover? (Select all that apply)
Signup and view all the answers
How does surface texture affect blood spatter?
Signup and view all the answers
How can directionality and angle of impact (AOI) be determined?
Signup and view all the answers
Define area of convergence (AOC).
Signup and view all the answers
What does area of origin (AOO) denote?
Signup and view all the answers
Study Notes
Blood Spatter Patterns
-
Angle of Impact: Refers to the acute angle between the direction of a blood droplet and the struck surface.
-
Area of Convergence: Indicates the location of the blood source on a two-dimensional plane, derived from intersections of lines through the long axes of stains.
-
Area of Origin: The three-dimensional space where the blood spatter originated.
-
Arterial Spray: Characterized by spurts of blood from a severed artery, with patterns evolving as the heart pumps.
-
Back Spatter: Blood that moves back towards the source of the force causing the spatter.
-
Cast-off Pattern: Created by blood droplets released due to movement of a blood-covered object.
-
Crime Scene Reconstruction: Hypothesis that outlines the sequence of events before, during, and after a crime.
-
Drip Trail Pattern: Bloodstains form a recognizable path as blood drips from a moving person or object.
-
Expirated Blood Pattern: Blood expelled from the mouth or nose due to internal injury, influenced by airflow.
-
Flow Pattern: Alteration in bloodstain shape and direction caused by gravity or object movement.
-
Forward Spatter: Blood that travels in the same direction as the source of energy that caused the spatter.
-
High Velocity Spatter: Patterns from high-speed impacts (over 100 ft/sec); typically produces droplets smaller than 1 mm.
-
Impact Spatter: Bloodstains produced from an object striking a blood source, ejecting blood droplets outward.
-
Low Velocity Spatter: Larger droplets (4 mm or more) caused by minimal applied force (up to 5 ft/sec).
-
Medium Velocity Spatter: Droplets with diameters between 1-4 mm stemming from a force of 5-25 ft/sec, commonly seen in attacks such as beatings.
-
Satellite Spatter: Small droplets around a primary blood drop resulting from its impact on a surface.
-
Skeletonization: Occurs when bloodstains dry, leading to a perimeter that can reveal the timing of the incident.
-
Transfer Pattern: Created when a bloodied object comes in contact with a clean surface, often revealing imprints.
-
Void Pattern: Indicates a blockage in blood spatter deposition, showing the outline of the obstructing object.
-
Sources of Blood Spatter: Include types like impact spatter, cast-off spatter, and arterial spray spatter.
-
Impact Bloodstain Patterns: Differentiates between forward spatter (outward) and back spatter (backward).
-
Classifying Impact Spatter: Velocity impacts classification; useful for understanding crime nature but not definitive in detail.
-
Gunshot Spatter: Comprises fine forward spatter from exit wounds and potential back spatter from entrance wounds.
-
Documenting Bloodstain Evidence: Critical for accuracy; involves noting, studying, and photographing patterns.
-
Bloodstains Can Tell a Story: Offers insights into the victim's movements, type of weapon used, and relationship to the assailant.
-
Methods for Documenting Evidence: Grid method and perimeter ruler method for accurate measurements around patterns.
-
General Bloodstain Features: Patterns on various surfaces reveal vital information about violent crime occurrences.
-
Pattern Interpretation: Reveals the blood's origin direction, impact angles, and victim positioning during the crime.
-
Effects of Surface Texture: Harder and less porous surfaces yield less spatter, while absorbent surfaces enhance spreading.
-
Directionality and Angle of Impact (AOI): Bloodstain shape indicates travel direction; angles can be measured using a specific trigonometric equation.
-
Area of Convergence (AOC): Assists in identifying the point where blood stains originated in a two-dimensional layout.
-
Area of Origin (AOO): Dimensions of blood projection can reveal the position of individuals during the injury event, approximated using string methods.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Test your knowledge of blood spatter patterns with these flashcards. Each card presents a term related to blood spatter analysis, along with its definition. Perfect for forensic science students or anyone interested in crime scene investigation.