Relative dating… First (oldest) Middle Last (youngest)

B must be older because it is underneath A (it got there first) Relative dates are not absolute (actual numbers). They are inferences about which MUST BE older. B must be older because it is underneath A (it got there first) WRONG SEQUENCE

Relative dates are not absolute (actual numbers). They are inferences about which MUST BE older. Click me!

There are 3 basic rules to follow when establishing a geologic sequence of events: Superposition: Unless “messed with”, the oldest layers are at the bottom. (For example, you put your socks on first, then your shoes)

There are 3 basic rules to follow when establishing a geologic sequence of events: Superposition: Unless “messed with”, the oldest layers are at the bottom. (For example, you put your socks on first, then your shoes) Cross-Cutting Relationships: younger events “cut across” older. (For example, an earthquake cannot break rock strata that are not formed)

There are 3 basic rules to follow when establishing a geologic sequence of events: Superposition: Unless “messed with”, the oldest layers are at the bottom. (For example, you put your socks on first, then your shoes) Cross-Cutting Relations: younger events “cut across” older. (For example, an earthquake cannot break rock strata that are not yet formed) Uniformitarianism: Earth processes have always been the same. (For example, deposited sediments have ALWAYS made sedimentary rock)

B C E J K H

M P Q T U Y

Sequence these geologic events Deposition C Deposition B Deposition A Intrusion D Fault line E

Which sequence is indicated by the strata in the outcrop? (1) A  B  C  D (3) A  B  D  C (2) D  C  B  A (4) B  A  D  C

(1) D → C → B → A → F (2) A → B → C → D → F And now…? The cross section shows rock layers A, B, C, D, and fault F. The rock layers have not been overturned. Which sequence places the rock layers and fault in order from oldest to youngest? E (1) D → C → B → A → F (2) A → B → C → D → F (3) F → D → C → B → A (4) F → A → B → C → D And now…? D → C → B → A → F → E

If Rock Unit D was deposited 210 million years ago, and Rock Unit B was deposited 340 million years ago, then igneous intrusion C probably occurred (1) 150 million years ago (3) 211 million years ago (2) 300 million years ago (4) 347 million years ago

If Rock Unit B was deposited 340 million years ago, then Rock Unit A probably occurred during which period? (1) Neogene (3) Permian (2) Pennsylvanian (4) Silurian

Rock Unit A was deposited during the Silurian. At this time (1) Extensive coal forming forests existed in NY (2) Index Fossil P (Cooksonia ) was alive in NY (3) The initial opening of the Atlantic Ocean occurred (4) Birds flew in NY skies

Based upon the diagram shown, the contact metamorphism of Rock Unit B probably creates (1) Gneiss (3) Basalt (2) Quartzite (4) Sandstone