Which environment is most likely to preserve trilobite fossils?

Which environment is most likely to preserve trilobite fossils?

• A. Desert
• B. Freshwater lake
• C. Deep marine
• D. Forest swamp

Answer: (C)

Trilobites were marine arthropods living on the sea floor, so the environments that best preserve their remains are those that promote rapid burial in fine marine sediments and limit decay and scavenging. Deep marine settings often accumulate fine-grained mud and clay and can experience bursts of rapid sedimentation, which quickly bury shells and protect them from decomposition and disturbance. Additionally, deeper waters can be low in oxygen, slowing decay and enhancing fossilization of hard parts like the trilobite exoskeleton. Desert conditions have little ongoing sediment deposition to bury organisms, freshwater lakes host mostly non-marine life, and forest swamps tend to preserve different types of organisms or plant material rather than marine arthropods. So the deep marine environment provides the most favorable combination of burial, sediment type, and chemistry for preserving trilobite fossils.

Trilobites were marine arthropods living on the sea floor, so the environments that best preserve their remains are those that promote rapid burial in fine marine sediments and limit decay and scavenging. Deep marine settings often accumulate fine-grained mud and clay and can experience bursts of rapid sedimentation, which quickly bury shells and protect them from decomposition and disturbance. Additionally, deeper waters can be low in oxygen, slowing decay and enhancing fossilization of hard parts like the trilobite exoskeleton. Desert conditions have little ongoing sediment deposition to bury organisms, freshwater lakes host mostly non-marine life, and forest swamps tend to preserve different types of organisms or plant material rather than marine arthropods. So the deep marine environment provides the most favorable combination of burial, sediment type, and chemistry for preserving trilobite fossils.