This is the first time that Rosneft specialists have diagnosed bacterial and sponge communities (frames) in well sections in Eastern Siberia in Cambrian sediments, the first geological period of the Paleozoic era. The discovery is of great importance for exploration and prospecting of oil and gas fields - it will help localize hydrocarbon deposits more precisely.

Bacterial-sponge frames were discovered by specialists of the Company's research center in Tyumen in the course of core description and study of petrographic shliphs*.

Large colonies of sponges of the Cambrian period were prevalent 570-500 million years ago at shallow depths and were larger and more numerous than the modern representatives of this biological species. Over hundreds of millions of years, the sponge and bacterial communities were transformed by pressure and temperature into carbonate source rocks that are now promising targets for exploration and production.

Previously, similar communities were described only in Cambrian rocks of China and North America.

Introduction of advanced approaches and new technologies is one of the key areas of Rosneft's 2030 strategy. The Company pays special attention to innovative development, emphasizing technological leadership as a key factor of competitiveness in the oil market.

* Shliph (thin rock section) is a thin plate of a rock or mineral glued to a slide. A standard petrographic shliph is 0.03-0.02 mm thick.

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Rosneft
November 21, 2023