The northern part of the East Java Basin has become a focus of research by earth scientists,
among others, because of the existence of hominid fossils and remains of other vertebrate
taxa within the Quaternary sedimentary sequence. Fossil-bearing layers are found in
the Kendeng Zone, mostly within the well-known Pucangan and Kabuh Formations, which
are distributed from Central to East Java. However, not all formations contain vertebrate
fossils as well as hominid elements. It is important to consider what factors may
have influenced the concentration of vertebrate fossils in those formations. In this
study, we describe sedimentary facies at three key field locations: Sangiran, Ngawi,
and Mojokerto. Our study indicates that vertebrate remains and hominid fossils mainly
accumulated in continental sediments associated with lacustrine and fluvial systems.
In this regard, Sangiran and Ngawi B offer the greatest prospect for yielding hominid
remains, owing to their unique paleoenvironmental and paleogeographical settings as
a highland during the Early–Middle Pleistocene period. Certain parts of the Kabuh
Formation in the Mojokerto region also hold high potential, especially those displaying
evidence of continental deposition.