Relative Dating
Which principle states that sedimentary layers are originally deposited in flat, horizontal layers?
a) Law of Superposition
b) Law of Original Horizontality
c) Principle of Cross-Cutting Relationships
d) Principle of Faunal Succession
b) Law of Original Horizontality ✅
Which situation best illustrates an unconformity?
a) Layers of basalt over granite
b) Sedimentary rocks directly on metamorphic rocks
c) Missing rock layers due to erosion
d) All of the above
d) All of the above ✅
Which dating method measures the exact age of a rock in years?
a) Relative dating
b) Fossil correlation
c) Absolute dating
d) Stratigraphic sequencing
c) Absolute dating ✅
Carbon-14 dating is useful only for:
a) Fossils older than 1 million years
b) Organic remains younger than ~50,000 years
c) Igneous rocks younger than 50,000 years
d) All types of minerals
b) Organic remains younger than ~50,000 years ✅
Which is an example of applying the Law of Original Horizontality in real life?
a) Determining if folded rock layers were disturbed after formation
b) Using fossil layers to date rock ages
c) Measuring radioactive decay
d) Identifying a half-life pattern
a) Determining if folded rock layers were disturbed after formation ✅
If sedimentary rock layers are found tilted, what does this suggest?
a) The rock formed underwater
b) Geological forces acted after deposition
c) The layers are the same age
d) The rock is igneous in origin
b) Geological forces acted after deposition ✅
The famous Siccar Point in Scotland is an example of:
a) Cross-cutting relationship
b) Angular unconformity
c) Disconformity
d) Nonconformity
b) Angular unconformity ✅
In radiometric dating, the original unstable atom is called the:
a) Daughter isotope
b) Parent isotope
c) Stable isotope
d) Neutral isotope
b) Parent isotope ✅
Uranium-Lead dating is ideal for:
a) Young volcanic rocks
b) Ancient rocks and zircons
c) Organic matter
d) Sedimentary layers only
b) Ancient rocks and zircons ✅
A basalt dike cutting across granite must be:
a) Older than the granite
b) The same age as the granite
c) Younger than the granite
d) Igneous in origin but unrelated in age
c) Younger than the granite ✅
According to the Law of Superposition, where is the oldest rock layer found in an undisturbed sequence?
a) At the top
b) In the middle
c) At the bottom
d) Near an unconformity
c) At the bottom
A nonconformity occurs when:
a) Tilted layers are overlain by flat ones
b) Parallel layers have erosion gaps
c) Sedimentary rocks rest on igneous or metamorphic rocks
d) Igneous intrusions cut across sediments
c) Sedimentary rocks rest on igneous or metamorphic rocks ✅
The time it takes for half of the radioactive atoms in a sample to decay is known as:
a) Half-life
b) Isotope interval
c) Decay period
d) Atomic turnover
a) Half-life ✅
Which Philippine site is mentioned as shaped by geological processes like tectonics and erosion?
a) Mayon Volcano
b) Tubbataha Reefs Natural Park
c) Chocolate Hills
d) Banaue Rice Terraces
b) Tubbataha Reefs Natural Park ✅
In the Grand Canyon, the Vishnu Schist is older than the Kaibab Limestone because:
a) It is darker in color
b) It is found at the bottom
c) It has more fossils
d) It contains volcanic ash
b) It is found at the bottom ✅
If a rock sample contains 25% of its original C-14, how many half-lives have passed?
a) 1
b) 2
c) 3
d) 4
b) 2 ✅
Which pair correctly matches method and suitable material?
a) Carbon-14 – igneous rocks
b) Potassium-Argon – organic remains
c) Uranium-Lead – ancient zircon minerals
d) Rubidium-Strontium – young bone samples
c) Uranium-Lead – ancient zircon minerals ✅
Which principle states that any rock feature cutting across another rock is younger than the rock it cuts?
a) Law of Superposition
b) Cross-Cutting Relationships
c) Law of Horizontality
d) Principle of Inclusion
b) Cross-Cutting Relationships ✅
Which method would be best for dating volcanic rocks older than 100,000 years?
a) Carbon-14 dating
b) Potassium-Argon dating
c) Uranium-Lead dating
d) Rubidium-Strontium dating
b) Potassium-Argon dating ✅
Which statement best distinguishes relative dating from absolute dating?
a) Relative dating is more accurate than absolute dating
b) Relative dating uses numerical ages, absolute dating does not
c) Relative dating orders events; absolute dating gives exact years
d) Both methods always give the same result
c) Relative dating orders events; absolute dating gives exact years ✅