Question

according to the law of superposition, what is the relative age of the rock layer found at the bottom of an undisturbed sequence?

• it depends on how the rock was formed to determine its age
• the rock layer at the bottom of an undisturbed sequence is older than those above it
• the rock layer at the bottom of an undisturbed sequence is younger than those above it
• the age depends on if its on a convergent or divergent boundary

the zoroaster granite(1,700ma) is found within the vishnu schist(1,750ma). which geologic principle best explains why the granite is considered younger than the schist?

• cross - cutting relationships
• faunal succession
• lateral continuity
• original horizontality

the grand canyon supergroup layers are tilted, what does the principle of original horizontality tell us about this orientation?

• the tilting happened during the deposition of the vishnu schist
• volcanic activity from the cardenas basalt caused the initial tilt
• the layers were tilted by tectonic activity after they were formed
• the layers were deposited on a steep underwater slope

which set of characteristics is required for a fossil to be classified as a good index fossil?

• must be a vertebrate animal and found only in deep ocean layers
• wide - spread geographically, short lived in time, and easy to find

Explanation:

First Question:

The Law of Superposition states that in undisturbed rock layers, the oldest layers are at the bottom and younger layers are above. So the bottom layer is older than those above.

The principle of cross - cutting relationships states that a geologic feature (like the Zoroaster Granite) that cuts through another (the Vishnu Schist) is younger than the feature it cuts. Faunal Succession is about fossil sequences, Lateral Continuity about rock layer continuity, and Original Horizontality about deposition orientation. So cross - cutting relationships apply here.

The Principle of Original Horizontality says that rock layers are deposited horizontally. If the Grand Canyon Supergroup layers are tilted, it means the tilting happened after their formation, likely due to tectonic activity. The other options go against this principle (e.g., deposition on a slope or tilting during deposition of another rock is incorrect).

Answer:

the rock layer at the bottom of an undisturbed sequence is older than those above it

Second Question: