Final answer:
The most extensively sampled record of dinosaur extinction is in eastern Montana, specifically the Hell Creek Formation. This location provides valuable information on the diversity and ecology of dinosaurs right before the mass extinction event that marked the end of the Cretaceous period.
Step-by-step explanation:
The most extensively sampled record of dinosaur extinction is in eastern Montana.
Eastern Montana has one of the most detailed and extensive fossil records related to the Cretaceous period, the geologic time when the mass extinction event that ended the reign of the dinosaurs occurred. This event is often referred to as the "great dying" and it marked the close of the Mesozoic Era, leading to the rise of mammals.
The Hell Creek Formation in Montana is particularly well-known for its well-preserved dinosaur fossils which provide deep insights into the latest stages of the Cretaceous and the first stages of the Paleogene periods. Here, paleontologists study the fossils to understand not only the diversity of dinosaurs just before their extinction but also the ecological dynamics and environmental changes that might have contributed to their abrupt disappearance.
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