What is the fine-grained topic of the following text: The Yezupil I archaeological loess site, situated in the East Carpathian Foreland (Ukraine), with two cultural layers (Middle and Upper Palaeolithic), has been systematically investigated by archaeologists and naturalists for about 20 years. Only return the topic.
Archaeological investigation of the Yezupil I loess site in the East Carpathian Foreland.