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Chapter 4 Physical properties of Glass and Soil

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Title: Chapter 4 Physical properties of Glass and Soil


1

Soil and Forensic Geology
2
What Is Soil?
  • Mixture of organic and inorganic material
  • May range from 100 inorganic (sand) to nearly
    100 organic (peat)
  • Inorganic part is minerals
  • Organic part is decayed plant and animal material
    and is sometimes called humus

3
Forensic Significance of Soil
  • Soil is class evidence - cannot be individualized
    to a particular location
  • There is no classification system for soils
  • Soils can be easily transported
  • Soils within a few meters horizontally or
    vertically differ

4
Forensic Analysis of Soils
  • Bulk analysis
  • Density gradient
  • Particle size distribution (sieving)
  • Inorganic components
  • Color (dissolve in water)
  • Petrography - mineral analysis Requires a good
    deal of skill and practice

5
Forensic Analysis of Soils
  • Organic components
  • Liquid chromatography
  • Oxygen availability
  • Bacterial DNA? - Future possibility

6
Why is soil such a good source of evidence?
  • Large Variations of soil characteristics
  • Extreme Complexity of its composition
  • Minerals
  • Oxides
  • Organic Matter
  • Microorganisms
  • Artificial additions (concrete, asphalt,
    plastics)
  • Runoff additions (salt, fertilizers, pesticides)
  • Manufactured products glass, paint, asphalt,
    brick, industrial products,
  • Complex Physical Nature
  • Varies due to above compositions

7
Forensic Geologists
  • The forensic Geologists examinations involve the
    identification of
  • Earth materials
  • Comparison of samples to determine common source
  • Studies that aid a criminal investigations and
    intelligence studies.

8
Forensic Geology In Intelligence Work
  • Remember the outcrop you saw behind Osama bin
    Laden on TV after September 11. What was the
    location?
  • A geologist who has done field work in the area
    would be able to locate that outcrop, and that
    actually happened Geologist John Shroder was
    able to identify the region where bin Laden had
    been sighted in Afghanistan in 2001 (see
    Geotimes, February 2002).

9
Forensic Geologists of the Past
  • Starting in 1887 Sir Arthur Conan Doyle wrote The
    Sherlock Holmes series used soil and residues
    many times to link individuals to specific
    locations.
  • In 1893, Hans Gross, authored Handbook for
    Examining Magistrates. In it he suggested
    that the dirt on someone's shoes could tell more
    about where a person had last been than many
    other techniques used in that time.

10
The Eva Disch Case
  • In October 1904 a dirty handkerchief containing
    bits of coal, snuff, and grains of the mineral
    hornblend was found at the murder scene of a
    seamstress named, Eva Disch.
  • A suspect was found who used snuff, and worked
    part-time at both a coal burning gas works and a
    quarry that had an abundance of the mineral
    hornblend.
  • The suspect also had two layers of dirt in his
    pant cuffs. The lower layer matched the soil at
    the crime scene and the upper layer,
    characterized by a particular type of mica
    particle, matched the soil found on the path to
    the victim's home.
  • When confronted with the evidence the suspect
    confessed. (Murray and Tedrow, 1991, p. 4)

11
Forensic Geologists
  • The microscope is and will remain an important
    tool.
  • Qualifications and competence of examiners is a
    major problem.
  • Should those qualifications be regionalized?
  • The future will see
  • Improved training of those who collect and
    analyze samples
  • Increased automated methods of examination
  • Improved research
  • The diversity of soils
  • What parts of soil are transferred during various
    types of contacts and could their be a pattern

12
Forensic Geologists Questions
  • Interconnected by the following questions
  • What is this material?
  • Where did this material come from?
  • Is this material unique to a crime scene or
    unique to circumstances under which a criminal
    act was committed?
  • What is the geologic context of a crime scene?

13
My Husband Went hunting and never came home ?
  • A pond with bentonite (clayish mud) in the
    mountains of western Colorado proved to be a
    really great place to camp for John Dodson.

14
Physical Properties of Soil
  • Soil Texture, Structure, Compaction
  • is the percent of sand, silt and clay in a soil.
  • sand is the coarsest (0.06 - 2 mm)
  • silt is intermediate (0.002 - 0.06 mm)
  • clay is the finest (lt0.002 mm)

15
Soil Texture
  • The texture of a soil is determined by the
    percentages of particles like sand, silt, clay
    that it contains.

16
Physical Properties of Soil
17
Soil Comparison
  • Simple observations using local geologists
  • Color of dry sample, (1,100 controls)
  • Texture of dry sample
  • Composition
  • Mineralogy, mineral crystalline solid
  • 2,200 minerals,
  • 40 commonly seen
  • ROCKS COMPOSION VARIES BASED ON MINERAL
    COMPOSITION
  • Mineral content
  • Grain size
  • LP Microscopy, shows animal, plant and
    artificial remains and their s
  • Side by side comparison

18
Minerals
  • Minerals are used by various commercial and
    industrial companies.
  • Brick, shale, plaster, and concrete are all found
    in many indoor products, drywall insulation.
  • Robbery suspects often have minerals within
    clothing fibers.
  • Why????
  • Locards Exchange Principle

19
Locards Exchange Principle
  • The exchange of materials between two objects
    that occurs whenever tow objects come into
    contact.

20
Physical Properties of Soil Organics
  • Humus a mixture of organic material that binds
    nutrient mineral ions and holds water.
  • Detritivores like Earthworms, termites, and ants
    help to breakdown humus.
  • Humus persists in agricultural soil for about 20
    years.
  • Humus ? CO2 H2O nutrient minerals

21
Physical Properties of Soil(Organisms)
  • Bacterial and Protozoan colonies
  • Plant litter
  • Fungi
  • Animal
  • Most common insects, arachnids, and annelids
  • Materials in varying states of decomposition

22
Physical Properties of Soil Soil Pore Spaces
  • Pore spaces Occupy about 50 of a soils volume
    and can be filled with H2O (soil H2O) or air
    (soil air).
  • Soil air is found in larger pores.
  • Soil H2O is found in smaller pores (0.05mm).

23
Physical Properties of Soil Soil Horizons
  • Horizontal layers of organized soil.
  • A soil profile is a vertical section from surface
    to parent material.

Differentiated Instruction Alert
24
Soil Horizon Basic
25
Soil Horizon Basic
  • Boreal Forest

26
Soil Horizons
27
Soil Horizons for Honors??
28
Soil Collection
  • Various interval 100 yard radius of the CS.
  • Sampling Surface and Subsurface layers
  • Approximately 1 tablespoon per sample
  • Individual plastic vials
  • On Suspect
  • Both soil and object are wrapped in paper
  • Layering effect on vehicles occurs over time due
    to sedimentation
  • Collected separately only if jarred loose

29
Laboratory Possibilities
  • Soil Comparisons
  • Soil nutrients, Nitrate and Phosphorus
  • Water holding capacity
  • Texture
  • pH
  • Organic Content
  • Sieve Percent Composition
  • Undisturbed vs. newly disturbed soil
  • Density
  • Leads to other chapters
  • Crime Scene
  • Impression
  • Foot and tire
  • Anthropology
  • Botanicals
  • Inductively coupled plasma mass spectrometry
    (ICPMS)
  • (Ask Mark He can get you one)

30
Soil Comparison
  • Differences in soils can identify location of
    victims, suspects, or the crime scene.
  • Or Inconsistencies between them!!
  • Remember the DEA SA Camarena?

31
Disturbed Soil Comparison
Newly disturbed Soil showing O-Layer(Organic)
fresh, organic topsoillayer
OldUndisturbedSoil same consistent color
32
Excavations
33
Lab Investigating Soil Core Sampling
34
Lab Finding Your Past
  • Objective Locate evidence of a past structure
    that is no longer in existence.
  • Hint Try to remember past homes, hangouts,
    relatives homes . Can you think of a structure
  • Change the color of your house?
  • Relocate a structure?

35
Lab Finding Your Past
36
Lab Finding Your Past
37
Lab Finding Your Past
38
Charcoal tells us what??
  • Another Attempted Cremation Like Hitler, Joseph
    and Magda Goebbels were cremated. The bodies of
    their six children remained in the bunker. They
    were found by Russian soldiers when Berlin fell
    to the Allies.

39
Density-Gradient Tube
  • Glass tubes measuring 6 to 10 millimetres in
    diameter and 25 to 40 centimetres in length are
    filled with several layers of two liquids mixed
    in varying proportions such that each layer has a
    different density.
  • An example is the mixture of tetrabromoethane,
    which has a density of 2.96 gmL-1 with ethane,
    with a density of 0.789 gmL-1.
  • The soil components then sink to the layers
    corresponding to their own density values and the
    distribution of particles can be compared between
    soil specimens.


Sample from Crime Scene
Sports Pitch
College Gardens
Courtyard
40
Inductively coupled plasma mass spectrometry
(ICP-MS)
  • The coupling of ICP-MS shows many advantages over
    other analysis techniques.
  • Benefits of the ICP over other radiation sources
    include improvement in excitation and ionization
    efficiencies and the reduction or elimination of
    many of the chemical interferences found in
    flames or furnaces.
  • Mass spectrometry generates a large amount of
    information, has high throughput capabilities,
    high sensitivity and low limits of detection.
    ICP-MS is capable of multi-elemental detection
    which reduces analysis time and therefore
    increases sample throughput. ICP-MS is one of the
    few analytical techniques that permits the
    quantifying of elemental isotopic concentrations
    and ratios.
  • It can achieve very low limits of detection

41
Inductively coupled plasma mass spectrometry
(ICP-MS)
  • An analysis of the elemental composition of the
    soil.
  • The plasma is formed by argon gas flowing through
    a radiofrequency field where it is kept in a
    state of partial ionization, i.e. the gas
    consists partly of electrically charged
    particles. This allows it to reach very high
    temperatures of up to approx. 10,000ºC.
  • The sample being analyzed is introduced into the
    plasma as a fine droplet aerosol. ICP-MS is the
    combination of an ICP with a mass spectrometer
    (MS).
  • The ions generated by the ICP are directed into
    the MS, which separates the ions according to
    their mass-to-charge ratio. Thus, ions of a
    selected mass-to-charge ratio can be detected and
    quantified.

42
Inductively coupled plasma mass spectrometry
(ICP-MS)
43
Inductively coupled plasma mass spectrometry
(ICP-MS)
44
Inductively coupled plasma mass spectrometry
(ICP-MS)
45
Inductively coupled plasma mass spectrometry
(ICP-MS)
46
Finito
47
Links
Website link Analytical Techniques for the
Comparison of Soil Samples
  • www.channel4.co.uk/.../S/science/
    images/fracture.gif
  • http//www.file///C/InetTemp/Content.IE5/QFML278
    9/256,1,All About Glass
  • http//www.adtdl.army.mil/cgi-bin/atdl.dll/fm/19-2
    0/Ch10.htm

48
Sewage leak do to inadequate Support
49
Sherlock Holmes
  • observation shows me that you have been to the
    Post Office this morning, but deduction lets me
    know that you dispatched a telegram.

50
Sherlock Holmes
  • It is simplicity itself. Observation tells me
    that you have a little reddish (soil) mould
    adhering to your instep. Just opposite the post
    office they have taken up the pavement and thrown
    up some earth. (It is) impossible to go to the
    post office without treading that dirt. The
    earth is a particular reddish color not found
    anywhere else in town observation the rest is
    deduction.

51
Some Interesting? Cases Where Geological Evidence
Has Been Important
  • Florida v. William Kennedy Smith
  • South Dakota v. Donald Eugene Moeller
  • Colorado v. Walter Osborne
  • The Death of a DEA agent Enrico Camarena

52
Florida v. William Kennedy Smith
  • WKS accused of rape of Patricia Bowman
  • Alleged attack on grass lawn behind Kennedy
    estate in W. Palm Beach, Fl
  • WKS alleged consensual sex on the beach near
    estate
  • Jay Siegel used PLM to compare samples from
    clothing of victim to lawn and beach areas
  • Samples consistent with beach, not lawn
  • WKS acquitted of rape

53
South Dakota v. Donald Eugene Moeller
  • Capital murder case of 9-year old Becky OConnell
    on May 8, 1990.
  • Testimony by soil expert refutes defendant alibi
  • Victim snatched off street, raped, killed, body
    dumped in woods.
  • Suspicion fell on Defendant because of prior sex
    crime involvement.
  • Found guilty and sentenced to death. Appeal
    resulted in reversal owing to admission of
    evidence of prior bad acts.

54
South Dakota v. Donald Eugene Moeller (cont.)
  • SD Supreme Court reversed and reinstated
    conviction
  • State geologist analyzed soil found in wheel
    wells of defendant pickup truck. Issue was
    whether soil came from crime scene South of Sioux
    Falls or from a road North of Sioux Falls where
    defendant claimed he was at time of crime
  • Geologist testified that soil could have come
    from crime scene.
  • Opinion based on
  • Colors and general characteristics
  • Soil was much lighter or could not have come from
    other roads in area
  • Sharp, clean hornblende crystals much more
    likely to have come from crime scene area

55
South Dakota v. Donald Eugene Moeller (cont)
  • Part of appeal called for striking geologists
    testimony as being too speculative as to
    conclusions
  • At 2nd trial, geologist came into more evidence
    from scene and wheel well dark green to black
    gahnite found at scene and in evidence from
    truck. This mineral extremely rare.

56
South Dakota v. Donald Eugene Moeller (cont)
  • Defense argued that geologist erred in
    identifying gahnite only by visual inspection.
    Claimed that PLM should have been used (to
    confirm that gahnite is isotropic) and that x-ray
    diffraction should have been used to confirm.
    Appeals court rejected appeal
  • There was no discussion at trial whether the
    finding of both hornblende and gahnite near Sioux
    Falls was a rarity or could be due to processing
    after mining elsewhere. Bedrock of Sioux Falls
    contains neither hornblende nor gahnite.

57
Colorado v. Walter Osborne
  • Osborne botches kidnapping of Adolph Coors from
    his ranch near Morrison and kills Coors
  • Ranch is near Dakota Hogback which is made of
    Dakota sandstone underlain by gray, green and
    maroon clay stones, shales, more sandstone and
    limestone. Dirt road near ranch was essentially
    eroded, pulverized components of hogback.

58
Colorado v. Walter Osborne (cont)
  • During kidnapping, a fight broke out and Osborne
    shot Coors. Fled in Osbornes yellow Mercury
    with body. Fled south onto an unpaved road in
    next county. Then went west and climbed. Road
    made of muddled dust pink-feldspar. Dust was
    granite, but compared to bedrock was deficient in
    iron and magnesium.
  • As he climbed further, came into Pikes Peak
    granite very distinctive.

59
Colorado v. Walter Osborne (cont)
  • At 7200 ft, Osborne dumped body in dump used by
    an Ashram. Body would not be found for 7 months.
  • Osborne went east and went on an unpaved road of
    black slags and drifted sands on a New Jersey
    barrier island. He hid car and torched it with
    gasoline.

60
Colorado v. Walter Osborne (cont)
  • FBI investigation turned up Osborne in New Jersey
  • Although Osborne (discovered to be Joseph
    Corbett, Jr) covered his tracks well but was
    writing his itinerary on the bottom of his car.
  • 4 depositional strata found
  • 4th contained material from around New Jersey
    dump where he burned car
  • 3rd contained pink feldspars of Pikes Peak
    granite near where body was found
  • 2nd had materials from Morrison hogback formation
    around Coors rangch
  • 1st had pink feldspars of other Front Range
    granites generally related to Rocky Mountain
    Front Range

61
Death of a DEA Agent Enrico Camarena
  • Story of how FBI geologist, Ron Rawalt was able
    to determine, with certainty, where Camarena body
    was buried, thus showing that Mexican govt. lied
    about how he was killed.
  • He noticed a TV report of the killings. The body
    was shown with soil clinging to it. The soil was
    obviously of a different color than the soil from
    the alleged burial site.

62
Death of a DEA Agent Enrico Camarena (cont)
  • He told the govt. that he could prove, with soil
    analysis alone, that Mexican govt. was lying
    about the murder.
  • He went to Mexico and collected a spoonful of
    soil from Camarena body. He compared that to the
    soil from the alleged burial site and found them
    to be entirely different.

63
Death of a DEA Agent Enrico Camarena (cont)
  • Soil from body
  • Spoke of mountains
  • 98 rhyolite ash (clean, high in silica, angular,
    vesicular) could be described as airfall
    pumice
  • Bixbyite blacker than coal
  • Pink glass of exceptional depth and richness of
    color, he had never seen anything like it, except
    in candy
  • 2 kinds of cristobalite opalized and clear,
    elongate and faceted, clear polygonal columns
    (octehedrons). Resembled branch coral. Very
    rare to find both types together.

64
Death of a DEA Agent Enrico Camarena (cont)
  • Pinpointing location
  • Research with Geological Survey and Smithsonian
    minerologists located specific location A
    Jalisco state park called Bosques de la Primvera.
    Cristabolite was the result of a third-event
    calderea formation.
  • Location is on upslope of mountain in park or
    park itself
  • Rawalt flew to Mexico as DEA agent (FBI agents
    were not allowed in to investigate

65
Death of a DEA Agent Enrico Camarena (cont)
  • While Rawalt was in Mexico searching for the area
    of burial, FBI was approached about a French
    consultant, Loic Le Ribault. He was the head
    petrologist for the French national oil company
    and was said to be able to do things geologically
    speaking, that other people couldnt do. Show
    him a few grains of sand and he could tell you
    where they came from

66
Death of a DEA Agent Enrico Camarena (cont)
  • Le Ribault
  • FBI tested him by giving him 3 samples
  • Ash from Mt. St. Helens
  • Alluvium from river delta in S. Carolina related
    to recent murder
  • Dirt from girders taken from bomb site in Beirut,
    Lebanon
  • Ribaults results
  • Got location of ash from Mt. St. Helens within a
    few miles of source
  • River basin in American Southest
  • Bekaa valley in Lebanon soil had been subjected
    to explosion

67
Death of a DEA Agent Enrico Camarena (cont)
  • Le Ribaults contribution to Camarena case
  • Was showed samples from park and body. He said
    you are there, but not there. Right elevation,
    but these are samples (from park) from an area
    washing north. The site is an area washing
    south.
  • Sand deposited by water 4-5 ft. deep in a draw.
    Slope of draw lt10 degrees. Shade predominates.
  • Rawalt found exact location from this data.

68
Soil and Arsenic poisoning
  •    Washington State Patrol Forensic Geologist
    Bill Schneck became involved in the investigation
    into the serious illness of a small child caused
    by arsenic poisoning.
  • The suspected person was absolved when an
    examination of the child's house revealed a
    number of mineral specimens left in the house and
    the yard by a former occupant who was a mineral
    collector. Many of those specimens were
    arsenopyrite, an iron arsenic sulfide.
  • The child had been eating and chewing on the
    material.

69
An Early Case The Father Patrick Heslin Case
  • In Colma, California on 2 August 1921 a priest,
    Father Patrick Heslin, was kidnapped and a ransom
    note was received, but there was no further
    contact from the kidnapper.
  • The priest's body was found on a local beach by
    William Hightower, a master baker. However, sand
    grains found on Hightower's knife and in his room
    matched the beach sand at the site where the body
    was found. Hightower was convicted of the murder
    and sentenced to life imprisonment in San Quentin.
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