1. Interpreting Geologic History

5. Relative Dating Techniques

11. oldest youngest

15. Law of Inclusions Which is older the Granite or the Sandstone? In figure A? In figure B? Sandstone is older Granite is older

27. FOSSILS GIVE US INFORMATION ABOUT THE ANCIENT ENVIRONMENT AND CLIMATE

31. Sedimentary layers (the law of original horizontality)

32. Sedimentary layers

33. Sedimentary layers

34. Sedimentary layers

35. Sedimentary layers

36. The fault came after the rock was formed

37. Sedimentary layers The tilt came after the the rock was formed

38. The extrusion came after the rock was formed 1 2 3 4 5 Contact metamorphism

39. 1 2 3 4 5 6 The extrusion came after the lower layers were formed but…. Before the top layer

40. 1 2 3 4 5 This intrusion came after all the layers

55. Law of Original Lateral Continuity

60. You can match the rock strata in one location with rock strata in more distant locations by Comparing , c o l o r texture composition sequence of layers

61. Time correlation compares ____________ contained in the rock strata index fossils 1 2 3 4 4 5 6 3

63. Which fossil would make the best index fossil? Found in only 1 layer (short lived) Found in all samples (widespread)

64. Another way of correlating layers by time is through ___________________ Volcanic ash falls

65. These ash falls are very ________ events. A single layer of ______ can be found over a large area, this allows geologists to make a__________________ from one location to another at the position of a common ash fall. brief ash time correlation

77. NEW BOTTOM LAYER APPEARS (EMERGES)

78. LAYER C IS MISSING EROSION

79. EROSION

80. THE UNCONFORMITY IS THE BURIED EROSIONAL SURFACE BETWEEN B AND D

83. ACTIVITY WHICH IS OLDER

89. ISOTOPE: An unstable element with different number of neutrons than a normal (stable) element. (Its unstable so wants to change to stable)

90. EX. C C 6 6 12 14 6 protons 6 protons 6 neutrons Unstable 8 neutrons

91. EX. C C 6 6 12 14 6 protons 6 protons 6 neutrons 8 neutrons unstable

92. D. If the nucleus has more or fewer than the normal number of ____________, the isotope may be ____________ neutrons radioactive (unstable)

94. This process is called… Radioactive Decay

105. Original=100% Decay product=0% 100/0 Or 1 to 0

106. Original=50% Decay product=50% 50/50 Or 1 to 1 After one Half-life:

107. Original=25% Decay product=75% 25/75 Or 1:3 After two Half-lives:

108. Original=12.5% Decay product=87.5% 12.5/87.5 After three Half-lives:

109. Original=6.25% Decay product=93.75% 6.25/93.75 After four Half-lives:

110. N 14 Ar 40 Pb 206 Sr 87 5.7 x 10 3 1.3 x 10 9 4.5 x 10 9 4.9 x 10 10 Element Decay Product Half-life