1. Ch 4 - Physical Properties: Glass and Soil Physical and chemical properties. Physical and chemical properties. Metric and British systems. Metric and British systems. Celsius (Centigrade) vs Fahrenheit. Celsius (Centigrade) vs Fahrenheit. Mass vs Weight. Mass vs Weight. Density Density Refractive Index Refractive Index Crystalline vs Amorphous solids. Crystalline vs Amorphous solids. Double refraction and birefringence. Double refraction and birefringence.

2. Dispersion of light through a prism. Dispersion of light through a prism. Flotation and immersion methods for comparing glass specimens. Flotation and immersion methods for comparing glass specimens. Examining glass fractures to determine the direction of impact from a projectile. Examining glass fractures to determine the direction of impact from a projectile. Proper collection of glass evidence. Proper collection of glass evidence. Forensic properties of soil. Forensic properties of soil. Density-gradient tube technique. Density-gradient tube technique. Proper collection of soil evidence. Proper collection of soil evidence. http://www.fbi.gov/hq/lab/handbook/examglas.htm http://www.fbi.gov/hq/lab/handbook/examglas.htm http://www.fbi.gov/hq/lab/handbook/examglas.htm http://www.fbi.gov/hq/lab/handbook/examsoil.htm http://www.fbi.gov/hq/lab/handbook/examsoil.htm http://www.fbi.gov/hq/lab/handbook/examsoil.htm

3. Physical property: describes the behavior of a substance without having to alter the substance’s composition through a chemical reaction Physical property: describes the behavior of a substance without having to alter the substance’s composition through a chemical reaction Chemical property: describes the behavior of a substance when it reacts or combines with another substance Chemical property: describes the behavior of a substance when it reacts or combines with another substance Fahrenheit scale: the temperature scale using the melting point of ice as 32 0 and the boiling point of water as 212 0, with 180 equal divisions or degrees between them. Fahrenheit scale: the temperature scale using the melting point of ice as 32 0 and the boiling point of water as 212 0, with 180 equal divisions or degrees between them.

4. Celsius scale: the temperature scale using the melting point of ice as 0 0 and the boiling point of water as 100 0, with 100 equal divisions or degrees between Celsius scale: the temperature scale using the melting point of ice as 0 0 and the boiling point of water as 100 0, with 100 equal divisions or degrees between Weight: a property of matter that depends on the mass of a substance and the effects of gravity on that mass Weight: a property of matter that depends on the mass of a substance and the effects of gravity on that mass Mass: a constant property of matter that reflects the amount of material present Mass: a constant property of matter that reflects the amount of material present Density: a physical property of matter that is equivalent to the mass-per-unit volume of a substance Density: a physical property of matter that is equivalent to the mass-per-unit volume of a substance

5. Refraction: the bending of a light wave as it passes from one medium to another Refraction: the bending of a light wave as it passes from one medium to another Refractive index: the ratio of the speed of light in a vacuum to its speed in a given substance Refractive index: the ratio of the speed of light in a vacuum to its speed in a given substance Crystalline solid: a solid in which the constituent atoms have a regular arrangement Crystalline solid: a solid in which the constituent atoms have a regular arrangement Atom: the smallest unit of an element; not divisible by ordinary chemical means. Atoms are made up of electrons, protons, and neutrons plus other subatomic particles Atom: the smallest unit of an element; not divisible by ordinary chemical means. Atoms are made up of electrons, protons, and neutrons plus other subatomic particles

6. Amorphous solid: a solid in which the constituent atoms or molecules are arranged in random or disordered positions. There is no regular order in amorphous solids. Amorphous solid: a solid in which the constituent atoms or molecules are arranged in random or disordered positions. There is no regular order in amorphous solids. Birefringence: a difference in the two indices of refraction exhibited by most crystalline materials Birefringence: a difference in the two indices of refraction exhibited by most crystalline materials Dispersion: the separation of light into its component wavelengths Dispersion: the separation of light into its component wavelengths Tempered glass: glass to which strength is added by introducing stress through the rapid heating and cooling of the glass surfaces Tempered glass: glass to which strength is added by introducing stress through the rapid heating and cooling of the glass surfaces

7. Becke line: a bright halo that is observed near the border of a particle immersed in a liquid of different refractive index Becke line: a bright halo that is observed near the border of a particle immersed in a liquid of different refractive index Radial fracture: a crack in a glass that extends outward like the spoke of a wheel from the point at which the glass was struck Radial fracture: a crack in a glass that extends outward like the spoke of a wheel from the point at which the glass was struck Concentric fracture: a crack in a glass that forms a rough circle around the point of impact Concentric fracture: a crack in a glass that forms a rough circle around the point of impact Mineral: a naturally occurring crystalline solid Mineral: a naturally occurring crystalline solid

8. Density-gradient tube: a glass tube filled from bottom to top with liquids of successively lighter densities; used to determine the density destruction of soil Density-gradient tube: a glass tube filled from bottom to top with liquids of successively lighter densities; used to determine the density destruction of soil

9. Ch. 4 – Glass and Soil Properties of Matter The distinguishing characteristics of a substance used in its identification & description The distinguishing characteristics of a substance used in its identification & description characteristics by which people are recognized characteristics by which people are recognized hair color, tone of voice, walk, shape of nose hair color, tone of voice, walk, shape of nose chemical substances are recognized by how they look & behave chemical substances are recognized by how they look & behave each chemical substance has a unique set of properties that distinguish it from all other substances each chemical substance has a unique set of properties that distinguish it from all other substances

10. Properties of Matter Chemical Properties Chemical Properties a characteristic of a substance that describes the way the substance undergoes or resists change to form a new substance a characteristic of a substance that describes the way the substance undergoes or resists change to form a new substance Physical Properties Physical Properties a characteristic of a substance that can be observed without changing the substance into another substance a characteristic of a substance that can be observed without changing the substance into another substance

11. Physical Properties Extensive Properties Extensive Properties depend on the amount of sample depend on the amount of sample volume, mass volume, mass Intensive Properties Intensive Properties do not depend on the amount of sample do not depend on the amount of sample melting point, density melting point, density

12. Density The ratio of the mass of an object to the volume occupied by that object The ratio of the mass of an object to the volume occupied by that object g/cm 3 (solids); g/mL (liquids) g/cm 3 (solids); g/mL (liquids) d = m/V Densities of solids & liquids are often compared to the density of water Densities of solids & liquids are often compared to the density of water sink or float sink or float Varies with temperature Varies with temperature

13. Refraction The bending that occurs when a light wave passes at an angle from one medium to another (air to glass) The bending that occurs when a light wave passes at an angle from one medium to another (air to glass) bending occurs because the velocity of the wave decreases bending occurs because the velocity of the wave decreases

14. Refractive Index (N D ) The ratio of the velocity of light in a vacuum to the velocity of light in a given medium The ratio of the velocity of light in a vacuum to the velocity of light in a given medium N D (water) = 1.333 N D (water) = 1.333 light travels 1.333 time faster in vacuum than in water light travels 1.333 time faster in vacuum than in water An intensive property An intensive property Varies with temperature and the light frequency Varies with temperature and the light frequency

15. Double Refraction Crystals refract a beam of light into two different light-ray components Crystals refract a beam of light into two different light-ray components extraordinary ray extraordinary ray refracted (bent) refracted (bent) ordinary ray ordinary ray path unchanged path unchanged Causes a double image to be seen Causes a double image to be seen No double refraction with isometric crystals No double refraction with isometric crystals

16. Birefringence The difference between the two indices of refraction The difference between the two indices of refraction for calcite: 1.486 & 1.658 for calcite: 1.486 & 1.658 birefringence for calcite is 0.172 birefringence for calcite is 0.172 Use in identifying crystals Use in identifying crystals

17. Dispersion Occurs when Occurs when an incident parallel beam of light to fans out according to the refractive index of the glass for each of the component wavelengths, or colors. an incident parallel beam of light to fans out according to the refractive index of the glass for each of the component wavelengths, or colors.

19. Glass The Basics

20. What is Glass? One of the oldest of all manufactured materials One of the oldest of all manufactured materials A simple fusion of sand, soda & lime (all opaque) A simple fusion of sand, soda & lime (all opaque) produces a transparent “solid” when cooled produces a transparent “solid” when cooled

21. What is Glass? An extended, 3D network of atoms which lacks the repeated, orderly arrangement typical of crystalline materials An extended, 3D network of atoms which lacks the repeated, orderly arrangement typical of crystalline materials The viscosity is such a high value that the amorphous material acts like a solid The viscosity is such a high value that the amorphous material acts like a solid

22. What is Glass? glass is formed upon the cooling of a molten liquid in such a manner that the ordering of atoms into a crystalline formation is prevented glass is formed upon the cooling of a molten liquid in such a manner that the ordering of atoms into a crystalline formation is prevented materials which form glasses are relatively rare materials which form glasses are relatively rare SiO 2 (silica) is the most common example SiO 2 (silica) is the most common example

23. Structure of Glass

24. Physical Properties At ordinary temp. At ordinary temp. internal structure resembles a fluid internal structure resembles a fluid random molecular orientation random molecular orientation external structure displays the hardness & rigidity of of a solid external structure displays the hardness & rigidity of of a solid Does not show a distinct melting point Does not show a distinct melting point on heating gradually softens on heating gradually softens on cooling gradually thickens on cooling gradually thickens

25. Physical Properties Common Properties Common Properties hard hard perfectly elastic perfectly elastic brittle brittle non-conductors of electricity non-conductors of electricity chemically stable chemically stable

26. Types of Glass Oxide Glasses

27. Types of Glasses ~a thousand chemical formulations ~a thousand chemical formulations each has its own combination of properties each has its own combination of properties more than 700 compositions in commercial use more than 700 compositions in commercial use Most common type encountered by the forensic scientist is “flat” glass Most common type encountered by the forensic scientist is “flat” glass glass used in windows & doors glass used in windows & doors

28. Components Formers Formers forms the glassy, non-crystalline structure forms the glassy, non-crystalline structure fluxes fluxes improve melting properties but impart low chemical resistance improve melting properties but impart low chemical resistance typically alkali or alkaline earth oxides typically alkali or alkaline earth oxides modifiers (stabilizers or intermediates) modifiers (stabilizers or intermediates) a material that improves stability a material that improves stability typically oxides of Ca, Al, or Zn typically oxides of Ca, Al, or Zn

29. Common Glass Components

30. Soda-lime-glass Silica itself makes a glass (fused silica) Silica itself makes a glass (fused silica) high mp (3133 o F or 1723 o C) high mp (3133 o F or 1723 o C) high viscosity in liquid state high viscosity in liquid state difficult to melt & work difficult to melt & work Na 2 O (soda) lowers melting temp (A flux) Na 2 O (soda) lowers melting temp (A flux) glass lacks durability (soluble in water) glass lacks durability (soluble in water) CaO (lime) increases stability CaO (lime) increases stability

31. Borosilicate Glass Over 5% B 2 O 3 added to the silica Over 5% B 2 O 3 added to the silica a heat resistant glass that expands only ~1/3 as much as silicate glass a heat resistant glass that expands only ~1/3 as much as silicate glass more resistant to breaking on rapid heating & cooling more resistant to breaking on rapid heating & cooling Pyrex Pyrex Uses Uses laboratory ware & thermometers laboratory ware & thermometers household glassware household glassware sealed-beam headlights sealed-beam headlights

32. Lead Glasses Incorporates up to 80% PbO Incorporates up to 80% PbO Has high refractive index & high electrical resistivity Has high refractive index & high electrical resistivity Suitable for hand fabrication Suitable for hand fabrication Uses Uses “crystal” tableware “crystal” tableware costume jewelry costume jewelry fine chandeliers fine chandeliers neon sign tubing neon sign tubing

33. Colored Glasses Metallic oxides or sulfides added to soda-lime glass Metallic oxides or sulfides added to soda-lime glass chromium oxide (green) chromium oxide (green) cobalt oxide (blue) cobalt oxide (blue) cadmium or selenium sulfide (red) cadmium or selenium sulfide (red) Colloidal particles of iron & sulfur produces the “carbon” brown beer bottle Colloidal particles of iron & sulfur produces the “carbon” brown beer bottle

34. Decolorized Glass General term for the soda-lime-glass marketed as “clear” for windows General term for the soda-lime-glass marketed as “clear” for windows Color caused by impurities present in the raw materials removed or masked Color caused by impurities present in the raw materials removed or masked destruction of carbonaceous matter destruction of carbonaceous matter oxidation of Fe(II) (blue) to Fe(III) (yellow) oxidation of Fe(II) (blue) to Fe(III) (yellow) NaNO 3, KNO 3,, BaNO 3 NaNO 3, KNO 3,, BaNO 3 Most “clear” glass is not absolutely colorless Most “clear” glass is not absolutely colorless observable by viewing on edge observable by viewing on edge

35. Light Sensitive Eyeglass Lenses Contain colloidal particles of silver halide Contain colloidal particles of silver halide Identified by exposure to uv light Identified by exposure to uv light

36. Glass Production Flat Glass Flat Glass until late 1950s produced by sheet * plate processes until late 1950s produced by sheet * plate processes primarily produced by the float glass process today primarily produced by the float glass process today molten glass is “floated” over a bath of molten time molten glass is “floated” over a bath of molten time produces a distortion-free sheet produces a distortion-free sheet

37. Glass Fracture Examination Types of Fractures

38. Impact Fractures Impact causes a pane of glass to bulge Side opposite the impact will stretch more & rupture first Radial cracks are rapidly propagated in short segments from the point of impact

39. Impact Fractures Ridges will be seen as irregularities on the broken edge of a radial crack Ridges will be seen as irregularities on the broken edge of a radial crack

40. Impact Fractures If the pane is held firmly on both sides If the pane is held firmly on both sides a circular pattern of cracks (concentric) will form around point of impact a circular pattern of cracks (concentric) will form around point of impact

41. Forensic Examination Ridges on radial cracks can be used to determine on which side of pane impact occurred Ridges on radial cracks can be used to determine on which side of pane impact occurred To perform examination To perform examination identify one or more pieces which have cracks terminating at a point of impact identify one or more pieces which have cracks terminating at a point of impact fit these pieces onto one or more pieces marked “inside” or “outside” fit these pieces onto one or more pieces marked “inside” or “outside”

42. Four R Rule Ridges on Radial cracks are at Right angles to the Rear (side opposite the impact)

43. Four R Rule Exceptions Exceptions tempered glass tempered glass “dices” without forming ridges “dices” without forming ridges very small windows held tightly in frame very small windows held tightly in frame can’t bend or bulge appreciably can’t bend or bulge appreciably windows broken by heat or explosion windows broken by heat or explosion no “point of impact” no “point of impact”

45. Heat Fractures typical heat crack is curved has a smooth edge (“mirror edge”) no indication of point of impact

46. Fractures Caused by Projectiles High-velocity projectiles High-velocity projectiles crater-like hole surrounded by a nearly symmetrical pattern of radial and concentric cracks crater-like hole surrounded by a nearly symmetrical pattern of radial and concentric cracks the size of the hole & diameter of crater are relatively independent of the size of the projectile the size of the hole & diameter of crater are relatively independent of the size of the projectile

47. Fractures Caused by Projectiles

48. Bullet Analysis If a window is broken by a bullet, it is possible to determine the bullet's direction by noting the side of the cone- shaped hole left by the bullet. The small opening is on the entrance side and the large opening is on the exit side. A determination of the sequence of bullet holes can be made by noting the radial fractures. Radial fractures caused by the passage of a bullet will stop at any pre- existing fracture.

49. Glass Cutters score the surface of glass by forcing out tiny chips along a line score the surface of glass by forcing out tiny chips along a line small chips will be missing on one side of the pane along the break small chips will be missing on one side of the pane along the break Cutter type can’t be accurately determined Cutter type can’t be accurately determined Association to a particular cutter possible only when glass chips are deposited on a cutter Association to a particular cutter possible only when glass chips are deposited on a cutter

50. Mechanical Fit Examiner can determine that two or more pieces of glass were broken from the same pane or object Examiner can determine that two or more pieces of glass were broken from the same pane or object Because glass is amorphous, no two glass objects will break the same way Because glass is amorphous, no two glass objects will break the same way

51. Figure 4-10 p. 98 Saferstein

52. Comparing Glass Fragments Using Physical Properties

53. Glass as Forensic Evidence Films of breaking glass have shown that glass flies backward from all parts of the window where cracks appear Films of breaking glass have shown that glass flies backward from all parts of the window where cracks appear not just from point of impact not just from point of impact Results in a shower of minute glass particles onto the window breaker Results in a shower of minute glass particles onto the window breaker

54. Glass as Forensic Evidence Glass fragments recovered from clothing Glass fragments recovered from clothing number & distribution are important number & distribution are important a piece of glass embedded in a shoe has low probative value a piece of glass embedded in a shoe has low probative value many small fragments from a shirt or sweater can be highly significant many small fragments from a shirt or sweater can be highly significant Glass must be classified Glass must be classified window glass vs broken bottle glass window glass vs broken bottle glass Individualization may be possible Individualization may be possible

55. Classification Tests Physical properties can be used to place glass into a class Physical properties can be used to place glass into a class Density Density Refractive Index (RI) Refractive Index (RI) Individualization can’t be determined from these properties alone Individualization can’t be determined from these properties alone Can be used to evaluate the significance of a glass comparison Can be used to evaluate the significance of a glass comparison

56. Flotation Test Based on density Based on density Glass is not perfectly homogeneous Glass is not perfectly homogeneous test allows for small internal density variations test allows for small internal density variations The control glass chip (known density) The control glass chip (known density) immersed in mixture of bromoform & bromobenzene immersed in mixture of bromoform & bromobenzene composition of mixture altered until the chip remains suspended composition of mixture altered until the chip remains suspended

57. Flotation Test The crime object (glass of unknown density) immersed in liquid mixture The crime object (glass of unknown density) immersed in liquid mixture remains suspended remains suspended liquid, control & unknown have same density liquid, control & unknown have same density sinks sinks unknown is more dense than control unknown is more dense than control different origins different origins Accurate density measurements can be obtained with a Density Meter Accurate density measurements can be obtained with a Density Meter

58. Refractive Index By Immersion Entails finding the temp at which a glass particle & a liquid, into which the chip has been immersed, have identical refractive indices Entails finding the temp at which a glass particle & a liquid, into which the chip has been immersed, have identical refractive indices refractive index of glass is relatively unaffected by changing temp refractive index of glass is relatively unaffected by changing temp refractive index of liquid varies with temp refractive index of liquid varies with temp dN/dT=-4 x 10 -4 / o C dN/dT=-4 x 10 -4 / o C

59. Refractive Index By Immersion Immerse glass in high boiling liquid Immerse glass in high boiling liquid Increase temp at rate of 0.2 o C/min Increase temp at rate of 0.2 o C/min At match point the refractive index of liquid & glass are the same At match point the refractive index of liquid & glass are the same Becke line disappears Becke line disappears minimum contrast between glass & liquid minimum contrast between glass & liquid If all glass fragments have similar match points, they have comparable RI If all glass fragments have similar match points, they have comparable RI

60. Figure 4-12 p. 101 Saferstein

61. Refractive Index By Immersion Internal RI variations may vary by 0.0002 Internal RI variations may vary by 0.0002 Differences in RI must be greater than 0.0002 between suspect & crime glass to be significant Differences in RI must be greater than 0.0002 between suspect & crime glass to be significant The measurement of RI alone can be of limited use for classification because RI distributions of flat glasses and container glasses overlap The measurement of RI alone can be of limited use for classification because RI distributions of flat glasses and container glasses overlap

62. Histogram = flat glasses Curve = container glasses

63. Other Classification Methods Microscopy Microscopy float glass is absolutely flat float glass is absolutely flat wine glasses are slightly curved wine glasses are slightly curved bottles have microscopic defects from mould bottles have microscopic defects from mould Fluorescence Fluorescence when excited by uv radiation, many glasses exhibit fluorescence when excited by uv radiation, many glasses exhibit fluorescence caused by heavy metals (including tin) caused by heavy metals (including tin)

64. Fluorescence Can differentiate between float and non-float window glass Can differentiate between float and non-float window glass Can differentiate between different samples of float glass in some cases Can differentiate between different samples of float glass in some cases (a) non-float glass or non-float side (b) float side Sample #1 (c) float side Sample #2

65. Scanning Electron Microcopy Can detect Can detect Si Si Na Na Ca Ca Mg Mg K very small samples can be analyzed (50 micrograms) very small samples can be analyzed (50 micrograms)

66. X-ray Fluorescence Can detect major elements in glass samples Can detect major elements in glass samples sometimes detects minor & trace level components sometimes detects minor & trace level components

67. Elemental Analysis Many of the trace elements enter the glass via trace impurities in the raw materials Many of the trace elements enter the glass via trace impurities in the raw materials Comparison of elemental analysis of crime glass & reference glass Comparison of elemental analysis of crime glass & reference glass if ranges of elements overlap for every element if ranges of elements overlap for every element indistinguishable indistinguishable if ranges of one or more elements are different if ranges of one or more elements are different samples are distinguishable samples are distinguishable

68. Red= flatblue= containerblack= tableware RI=1.5177-1.5183

69. Soil Analysis What Is Soil? Mixture of organic and inorganic material Mixture of organic and inorganic material May range from 100% inorganic (sand) to nearly 100% organic (peat) May range from 100% inorganic (sand) to nearly 100% organic (peat) Inorganic part is minerals Inorganic part is minerals Organic part is decayed plant and animal material and is sometimes called humas Organic part is decayed plant and animal material and is sometimes called humas

70. Soil Analysis "For example, observation shows me that you have been to the Wigmore Street Post-Office this morning, but deduction lets me know that when there you dispatched a telegram." "Right!" said I. "Right on both points! But I confess that I don't see how you arrived at it. It was a sudden impulse upon my part, and I have mentioned it to no one." "It is simplicity itself," he remarked, chuckling at my surprise--"so absurdly simple that an explanation is superfluous; and yet it may serve to define the limits of observation and of deduction. Observation tells me that you have a little reddish mould adhering to your instep. Just opposite the Wigmore Street Office they have taken up the pavement and thrown up some earth, which lies in such a way that it is difficult to avoid treading in it in entering. The earth is of this peculiar reddish tint which is found, as far as I know, nowhere else in the neighbourhood. So much is observation. The rest is deduction." (From The Sign of Four by Arthur Conan Doyle)

71. Soil Analysis Forensic Geology is the scientific application of earth sciences to legal matters. Forensic Geology is the scientific application of earth sciences to legal matters. Identifying, analyzing, and comparing earth materials, such as soil, rocks, minerals, and fossils found on or in a receptor (e.g., a suspect, a vehicle or other medium of transfer, such as water) to possible source areas (e.g., a crime scene, an alibi location, and/or a point of disposal/release). Identifying, analyzing, and comparing earth materials, such as soil, rocks, minerals, and fossils found on or in a receptor (e.g., a suspect, a vehicle or other medium of transfer, such as water) to possible source areas (e.g., a crime scene, an alibi location, and/or a point of disposal/release). Goal - Goal - establish the degree of probability that the material was or was not derived from a particular location establish the degree of probability that the material was or was not derived from a particular location determine the time an incident occurred, the cause of an incident and/or responsibility for an incident. determine the time an incident occurred, the cause of an incident and/or responsibility for an incident.

72. Soil Analysis Bulk analysis Bulk analysis Density gradient Density gradient Particle size distribution (sieving) Particle size distribution (sieving) Inorganic components Inorganic components Color (dissolve in water) Color (dissolve in water) Petrography - mineral analysis Petrography - mineral analysis Organic components Organic components Liquid chromatography Liquid chromatography Oxygen availability Oxygen availability Bacterial DNA? Bacterial DNA?

73. Soil Analysis Hit and Run: - Under-fender dirt/soil deposited at impact with the victim was used to locate the car/driver; also, matching the grease on the victim with the grease under the car provided supporting evidence. Rape: - Soil on clothing of a suspected rapist was used to place the suspect at the crime scene and to eliminate the suspect's alibi. Murder: - Soil found on murder victims used to determine the location of homicides, especially when the murder occurs in one location and the body is then moved. Using water-current measurements, bodies/objects thrown into water can be located and where a discovered body/object originally entered the water determined. Assault: - Identifying the type of rocks used as weapons led to the source of the rocks and helped locate suspects.

74. Soil Analysis Soil provided strong evidence against a rape suspect when comparison of soil samples on each knee of his pants matched the soil types from the right and left knee impressions at the rape scene. In other cases, analyses of soil on clothing have been used to support alibis and show no connection of the suspect to the crime scene. Soil provided strong evidence against a rape suspect when comparison of soil samples on each knee of his pants matched the soil types from the right and left knee impressions at the rape scene. In other cases, analyses of soil on clothing have been used to support alibis and show no connection of the suspect to the crime scene. By identifying the nature and extent of groundwater contamination, a forensic geologist determined the time a chemical release contaminated water supplies. In another case, a similar analysis showed that contamination in groundwater at a company originated at another property and a different company was responsible for cleanup. By identifying the nature and extent of groundwater contamination, a forensic geologist determined the time a chemical release contaminated water supplies. In another case, a similar analysis showed that contamination in groundwater at a company originated at another property and a different company was responsible for cleanup. By analyzing road maintenance records and techniques used to sample an unpaved road, a forensic geologist provided evidence that eliminated the validity of the opposition's roadway data and skid testing in a motor vehicle accident case. Geologic analyses of roadways in other cases have shown that unpaved roads were improperly constructed and/or improperly maintained. By analyzing road maintenance records and techniques used to sample an unpaved road, a forensic geologist provided evidence that eliminated the validity of the opposition's roadway data and skid testing in a motor vehicle accident case. Geologic analyses of roadways in other cases have shown that unpaved roads were improperly constructed and/or improperly maintained.

75. Soil Analysis (1908) A man with a bad reputation was under investigation for the murder of Margaeth Filbert in Bavaria, Germany. Investigating mud on the suspect's shoes helped solve the case. The suspect's wife testified that she had cleaned her husband's shoes the day before the crime. Those shoes had three layers of soil adhering to the leather in front of the heel with the innermost layer as the oldest. It contained goose droppings et al, matching samples from the walk outside the suspect's home. The second layer contained red sandstone fragments that compared with samples taken where Filbert's body had been found. The last layer contained brick, coal dust, cement and other materials that matched samples taken outside a castle where the suspect's gun and clothing had been found. The suspect's wife testified that she had cleaned her husband's shoes the day before the crime. Those shoes had three layers of soil adhering to the leather in front of the heel with the innermost layer as the oldest. It contained goose droppings et al, matching samples from the walk outside the suspect's home. The second layer contained red sandstone fragments that compared with samples taken where Filbert's body had been found. The last layer contained brick, coal dust, cement and other materials that matched samples taken outside a castle where the suspect's gun and clothing had been found. The suspect claimed he'd been walking in his fields the day of the crime. The lie didn't stick. Those fields were underlain by porphyry with milky quartz, and the soil had been wet that day. But they found no such material on the suspect's shoes. The suspect claimed he'd been walking in his fields the day of the crime. The lie didn't stick. Those fields were underlain by porphyry with milky quartz, and the soil had been wet that day. But they found no such material on the suspect's shoes.

76. Soil Analysis Soil is frequently found on clothing, shoes, or tools and in the wheel wells of vehicles. Most soil analysis consists of comparing two or more samples by their mineral content, color, and density. The presence of pesticides and herbicides have also been used in soil comparison.

77. Soil Analysis THE CAMARENA CASE In 1985, an agent with the U.S. Drug Enforcement Agency, Enrique Camarena Salazar, was kidnapped near Guadalajara. The U.S. government demanded that the Mexican government and Mexican Federal Judicial Police (MFJP) find Camarena. Eventually the MFJP announced finding Camarena's body on the El Mareno ranch in Michoacan State, the site of a shootout between Mexican police and alleged drug dealers. In 1985, an agent with the U.S. Drug Enforcement Agency, Enrique Camarena Salazar, was kidnapped near Guadalajara. The U.S. government demanded that the Mexican government and Mexican Federal Judicial Police (MFJP) find Camarena. Eventually the MFJP announced finding Camarena's body on the El Mareno ranch in Michoacan State, the site of a shootout between Mexican police and alleged drug dealers. But an investigation by the FBI showed that Camarena's body had been buried elsewhere before arriving at the ranch. The clue was a specific tuffaceous rhyolite ash found in material adhering to Camarena's exhumed body. The ash helped investigators find Camarena's original burial site - a grave in a state park called Bosques de la Primavera, far from the ranch. The body had been removed from that site to the ranch, and the investigation helped reveal a cover-up by the MFJP. But an investigation by the FBI showed that Camarena's body had been buried elsewhere before arriving at the ranch. The clue was a specific tuffaceous rhyolite ash found in material adhering to Camarena's exhumed body. The ash helped investigators find Camarena's original burial site - a grave in a state park called Bosques de la Primavera, far from the ranch. The body had been removed from that site to the ranch, and the investigation helped reveal a cover-up by the MFJP.

78. Soil Analysis Microscopic fossils called diatoms were once very prominent on Earth, and collectively deposited to form a sedimentary rock called diatomaceous earth. Some manufacturers use diatomaceous earth for insulating safes, that are used to store valuables. Burglary crimes have been solved by examining white specks from suspects' hair and clothing to determine that the specks were actually diatoms that came from broken safes at crime scenes, and not dandruff as the suspects had claimed. Microscopic fossils called diatoms were once very prominent on Earth, and collectively deposited to form a sedimentary rock called diatomaceous earth. Some manufacturers use diatomaceous earth for insulating safes, that are used to store valuables. Burglary crimes have been solved by examining white specks from suspects' hair and clothing to determine that the specks were actually diatoms that came from broken safes at crime scenes, and not dandruff as the suspects had claimed.