Name Date:______ Earth Science HW Period AWS
Name _____________________________________________ Date:____________ Earth Science HW Period:__________ Correlation of Rock Layers Base your answers to questions 1 through 5 on the cross sections below, which show widely separated outcrops at locations X, Y, and Z.
1. Which rock layer is oldest? A. gray siltstone B. green shale C. tan limestone D. brown limestone 2. Which event happened first at location Z? A. formation of brown siltstone B. fault C. unconformity D. formation of black shale 3. An unconformity can be observed at location Z. Which rock layer was most probably removed by erosion during the time represented by the unconformity? A. conglomerate B. gray siltstone C. black shale D. brown siltstone
4. The fossils in the rock formation at location X indicate that this are was often covered by A. tropical rain forests B. glacial ice C. desert sand D. seawater 5. Which rock layer was formed by the compaction and cementation of particles that were all less than 0.0004 centimeter in diameter? A. red sandstone B. green shale C. brown siltstone D. conglomerate
Base your answers to questions 81 through 83 on the cross sections below, which show widely, separated outcrops at locations W, X, Y, and Z. The rock layers have not been overturned. Line AB in the cross section at location W represents an unconformity. Fossils are shown in some of the layers.
Determine the relative geologic age of the four fossils by correlating the rock layers between these outcrops. Number the fossils from 1 to 4 in order of relative age, with 1 as the oldest and 4 as the youngest.
What evidence shown in the outcrop at location W suggests that the igneous intrusion occurred after both fossils were deposited at location W? Identify two of the processes involved in the formation of the unconformity represented by line AB in the cross section at location W.
Process 1:__________________________________________________
Process 2:__________________________________________________
1. Which rock layer is oldest? A. gray siltstone B. green shale C. tan limestone D. brown limestone 2. Which event happened first at location Z? A. formation of brown siltstone B. fault C. unconformity D. formation of black shale 3. An unconformity can be observed at location Z. Which rock layer was most probably removed by erosion during the time represented by the unconformity? A. conglomerate B. gray siltstone C. black shale D. brown siltstone
4. The fossils in the rock formation at location X indicate that this are was often covered by A. tropical rain forests B. glacial ice C. desert sand D. seawater 5. Which rock layer was formed by the compaction and cementation of particles that were all less than 0.0004 centimeter in diameter? A. red sandstone B. green shale C. brown siltstone D. conglomerate
Base your answers to questions 81 through 83 on the cross sections below, which show widely, separated outcrops at locations W, X, Y, and Z. The rock layers have not been overturned. Line AB in the cross section at location W represents an unconformity. Fossils are shown in some of the layers.
Determine the relative geologic age of the four fossils by correlating the rock layers between these outcrops. Number the fossils from 1 to 4 in order of relative age, with 1 as the oldest and 4 as the youngest.
What evidence shown in the outcrop at location W suggests that the igneous intrusion occurred after both fossils were deposited at location W? Identify two of the processes involved in the formation of the unconformity represented by line AB in the cross section at location W.
Process 1:__________________________________________________
Process 2:__________________________________________________
