Abstract

The stratigraphic subdivision and nomenclature in the N.E. Kalimantan Basin have always been problematic. Although much data of variable quality was gained from work carried out since the 19th Century through the present very little, however, has been published on this area. In order to more efficiently explore the N.E. Kalimantan Basin for hydrocarbons, it was necessary to build an integrated stratigraphic and sedimentary picture of this area. In establishing the stratigraphy and depositional cycles of N.E. Kalimantan, the authors were basically guided by the regional depositional cycles in Sundaland (Baumann, 1982) and the conceptual model of Vail's global sea level changes (1977). However, this new study suggests that the stratigraphy of the N.E. Kalimantan Basin can be grouped into simplified lithologic units, which reflect five major depositional cycles.

The main regressional phase of each cycle normally is evidenced by the development of littoral/paralic facies, delta complexes or unconformities while the following transgressive phase was accompanied by deposition of carbonates and marine shales.

This paper hopefully will contribute to the recognition of new exploration targets and help to justify a new round of exploration in N.E. Kalimantan.