Notes
These hand-written notes can be used for the midterm exam. If you miss notes due to absence, you can
go to www.biopalme.com to complete the notes using the posted power point presentations.
Trace Evidence I – Forensic Geology
Slide 2: Forensic Geology
 The legal application of ___________________________________________________________

Almost always an issue of _________________________

Can be __________________________ under the right circumstances
Slide 3: Forensic Geology
 Important Forensic properties
o ________________________________________
o
________________________________________
o
________________________________________
o
________________________________________
o
________________________________________
Slide 4: Forensic Geology Uses

Vehicle Accidents
o

Rape/Assault
o

_______________________________________________________________________
________________________________________________________________________
Burglary
o
________________________________________________________________________
________________________________________________________________________
Slide 5: History of Forensic Geology


1887–1893
o
___________________________________________________
o
Several Sherlock Holmes cases suggested the possible use of soil in criminal
investigations
1893
o
_______________________________________________________________________
o
First manual included the study of ___________________________________________
________________________________________________________________________
Slide 6: History of Forensic Geology

1910
o
______________________________________________
o
Was interested in the fact that ______________________________________________
_______________________________________________________________________

Helped to establish his Exchange Principle
Slide 7: What is Forensically Valuable?

______________________________________________________________

______________________________________________________________

______________________________________________________________

______________________________________________________________
Slide 8: Geologic Terminology

Geology
o

Mineralogy
o

________________________________________________________________________
Petrology
o

________________________________________________________________________
________________________________________________________________________
Paleontology
o
________________________________________________________________________
Slide 9: Minerals and Rocks

To be considered a mineral, 5 requirements must be met
o
________________________________________________________________________
o
_________________________ (Exception: material formed by the activity of animals...pearls)
o
_________________________
o
Definite ______________________________________ which provides for specific
_____________________________________________
o

________________________________________________________________________
_____________________ exist but only a few dozen are found in large quantities
Slide 10: Minerals and Rocks

Rock
o
An group of ______________________________________________________________
o
Each ________________________ found in the rock keeps its original properties
o
A few rocks contain only _______________________________________ (calcite – limestone)
Slide 11: US Constitution, 4th Amendment

Rocks come in three major types

Igneous
o

Sedimentary
o

The direct result of _______________________________________________________
The result of _____________________________________________________________
Metamorphic
o
The result of _____________________________________________________________
_______________________________________________________________________
Slide 12: Mineral and Rock Identification

Minerals are largely identified by specific ______________________________________________

Rocks are largely identified by ______________________________________
o
Properties can vary since there’s no specific _____________________ for a rock
o
Example: Granite
Slide 13: Mineral and Rock Identification

In general (not considering geologic setting)
o
Quartz is __________________________________________________________________
o
Most earth samples will contain only ________________different minerals and rocks
o
75% of anything picked up will be a ____________________________________________
Slide 14: Forensic Mineralogy Essentials

Among the most useful and reliable of properties

____________________Scale

o
Used as a ________________________
o
____________________
_____________________________________ Scale
o
Uses approximations of common items

Fingernail = 2.5

Penny = 3

Glass = 5.5

Steel = 7
Slide 15: Forensic Mineralogy Essentials

Density
o
Determined by relative __________________________________________ and
________________________________________________________________________

Most rock forming minerals: _____________________ g/cm3

Most metallics: _______________________ g/cm3
Slide 16: Forensic Mineralogy Essentials

Luster
o
_________________________________________________________________________
______________________________________________ ___________________________
o

Main classifications are _____________________ and _____________________________
Non-metallic subcategories
o
__________________________
o
__________________________
o
__________________________
o
__________________________
o
__________________________
o
__________________________
o
__________________________
Slide 17: Forensic Mineralogy Essentials

Color
o
Not a reliable property since _________________________________________________
_______________________________________________________________ (Corundum)
o

Only a few minerals occur in one color
General guesses about composition can be made based on colors
o
Dark (black, greys, greens, etc.) - _______________________________________________
o
Light (tans, clears, reds) - _____________________________________________________
Slide 18: Forensic Mineralogy Essentials

Streak
o
Color of the mineral in a _____________________________________________________
o
Found by rubbing the mineral across a __________________________________________
o
Streak the same regardless of mineral color differences
o
Reliable for hardnesses of______________________________________________
Slide 19: Forensic Mineralogy Essentials

Quartz
o
__________________________________________________________________
o
Often looks like _____________________________________________________
o
Can appear in ______________________________________________________
o
Will easily _________________________________________________________
Slide 20: Forensic Mineralogy Essentials

Feldspar
o
_________________________________________________________________
o
_________________________________________________________________
o
Will often have ____________________________________________________
Slide 21: Forensic Mineralogy Essentials

Mica
o
______________________________________________________________________
o
______________________________________________________________________
o
______________________________________________________________________

1 – ____________________________________ (more common)

2 – ____________________________________
Slide 22: Forensic Mineralogy Essentials

Calcite
o
_____________________________________________________________________
o
_____________________________________________________________________
o
______________________________________________________________________
o
______________________________________________________________________
Slide 23: Forensic Mineralogy Essentials

Hornblende and Pyroxene
o
______________________________________________________________________
o
Almost always _____________________________
o
_____________________________in most settings
Slide 24: Forensic Mineralogy Essentials

Granite
o
Most common ____________________________________________
o
Combination of ___________________________________________ discussed earlier
Slide 25: Forensic Mineralogy Essentials

Sandstone (sed.) and quartzite (meta.)
o
Typically ________________________________________________________________
o
Looks like___________________
o
Quartzite will have similar color but sand grains will be smashed/fused together
Slide 26: Forensic Mineralogy Essentials

Limestone (sed.)
o
Limestone is almost always _________________________________________________
o
Will ____________________________________________________________________
o
Metamorphic version is ________________________(uncommon)
o
Also look for __________________________________ – limestone is composed of calcite
Slide 27: Forensic Mineralogy Essentials

Shale (sed.) and slate (meta.)
o
______________________________________________________________________
o
______________________________________________________________________
o
Usually ___________________ but also __________________ or ____________________
o
Shale is ____________________________________
o
Slate will be ______________________________________________________________
Slide 28: Forensic Mineralogy Essentials

“Sand”
o
_______________________________________________________________________
o
“Sand” is a general term that describes _______________________________________
_______________________________________________________________________

_________________> > ________________> > _________________> > ___________________
Slide 29: Forensic Mineralogy Essentials

Siltstone (sed.)
o
Similar to _________________________________________________________________
o
Often _____________________________ (look for the “shine”)
o
_________________________________________________________________________
o
Usually a ____________________________________________
Slide 30: Mineral and Rock Identification

Geologic Setting
o
The sum total of ____________________________________ (past and present) for a particular area
o
Absolutely essential in any geologic investigation
o
Greatly assists in _____________________________________________ possible geologic “species”
Slide 31: UD Geologic Setting

Light colored minerals are common
o
_____________,_________________________,_______________________________

Micas especially common in ______________________________________________________

Most rocks will be ________________________or their __________________________ versions
o

____________________,____________________,__________________ are common
Many ___________________________________________ minerals/rocks
Soil Science – Trace Evidence II
Slide 2: Soil and Forensics

Used in much the same way as _________________________________________________

Soil represents a combination of ______________________________________________ components

Classified much more scientifically than most think
o
Example: __________________________ different types are recognized
Slide 3: Soil and Forensics

May establish a relationship or link to _______________________________________________
______________________________________________________________________________

Physical properties—_____________________________________________________________
______________________________________________________________________________

Chemical properties—____________________________________________________________
Slide 4: Soil and Forensics

Types of earth materials are virtually unlimited
o
___________________________________ and can change ____________________________
____________________________________________________________________________

Statistical probability of a given sample having properties the same as another is __________________

______________________________________ of soil can be excellent
Slide 5: Soil Formation Factors

Defined as a ______________________________________________________________________
along with ________________________________________________________________________.

_________________________________________________________________________________

Largely the result of:
o
_____________________________– decomposition or disintegration
o
_____________________________ – transport of material by wind/water
Slide 6: Soil Formation Factors

__________________________________________________________________________

__________________________________________________________________________

__________________________________________________________________________

__________________________________________________________________________

___________________________________________________________________________
Slide 7: Soil Components

_________________________________________
o


The source of the weather material that produced the soil
___________________
o
______________________________________________
o
Referred to as __________________________________
__________________________
o
Deeper soil layers
o
Minimal __________________________________
Slide 8: Soil Particle Sizes

Soil can be classified by ____________________________

Gravel: ____________________

Sand: _____________________

Silt: between ________________________________

Clay: _______________________________________
Slide 9: Particle Size Classification

Accomplished by placing sample through a series of _____________________

Percentages of each soil particle size are______________ and _________________________ on a chart
Slide10:
See last page of packet for diagram
Slide 11: Classification

Almost always done by _____________________________________________________________

________________________________________________ are the most important properties

Must be examined _________________________________________________________________

There are approx. _______________________different soil colors

Requires use of microscopes
o
______________________________________________ are the most useful
Slide 12: Color Classification

___________________________________ are created by _______________ content in the soil

___________________________________are created by high amounts of ________________ material

Usually based on the ________________________color chart
o
The basis for most computer graphics models
Slide 13: Color Classification

_______________Values
o

Require specific computerized devices for accurate measurements
o

Based on amounts of _______________________________________________ hues
“eyeball” measurements can also be made since human eye is very sensitive to color
Usually expressed in ____ values from ___________________
Slide 14: Color Classification
See last page of packet for diagram
Slide 15: Munsell Color Chart



Hue
o
Based on ____________ main values
o
__________________________________________________________________________
Value
o
A factor of _____________________________________
o
“10” = _________________, “0” = __________________
Chroma
o
_____________________ of color
Slide 16: Munsell Color Chart
See last page of packet for diagram
Slide 17: Color Classification
Use of a _______________________________________ during a forensic geology investigation