The paper presents the information necessary for identification of oil and gas promising objects using the results of seismic exploration in complicated geological and geophysical settings of salt-dome tectonics in Caspian Basin. The authors discuss the reasons of instability of determination of promising subsalt and suprasalt deposits depth, which depend on many factors. It is shown that one of the key factors is proper investigations of dramatic vertical and lateral changes in salt-bearing and suprasalt rock associations overlying the subsalt deposits. The authors demonstrate the seismic exploration alone is not enough to solve the salt-dome tectonics problems in the Caspian Basin. It is necessary to use the additional geophysical methods, because answering the questions on geological object origin and structure on the basis of seismic data only is prone to mistakes. Therefore, it is necessary to involve a number of geophysical studies and, besides seismic data, to use geopotential (gravity and magnetic) fields, which allow clarifying geometry of salt domes and, as a consequence, will help in more reliable identification of hydrocarbon traps and reducing drilling risks. The material presented herein is the authors attempt to once again emphasize the key mistakes of subsalt and suprasalt deposits delineation. They are drawing attention of geologists and geophysicists to the main negative factors arising during hydrocarbon trap identification in complicated geological and geophysical conditions.

Kseniya B. Sokulina
Candidate of Geological and Mineralogical Sciences,
Associate Professor, Scientific Adviser
LLC «TcGM NIR Povolzhya»;
410033, Saratov, Gvardeiskaya, 23B
e-mail: sokulinakb@cgmnir.ru
SPIN: 5422-7166

Sergei E. Voitovich
Chief Geologist, First Deputy Head of Administration
Tatar Geology and Prospecting Administration
of TATNEFT
14/59, ul. Tatarstan, Kazan, 420021, Republic of Tatarstan
e-mail: voytovich@tatneft.ru

Polina F. Popova
Leading Geophysicist
LLC «TERRAPOD»
410033 Saratov, Gvardeiskaya, 23B
e-mail: popovapf@cgmnir.ru

Gulnaz F. Khusnullina
Chief Geophysicist
LLC «TcGM NIR Povolzhya»
410033, Saratov, Gvardeiskaya, 23B
e-mail: khusnullina@cgmnir.ru

Evgenii V. Sivozhelezov
Chief Geologist
LLC «TERRAPOD»
410033, Saratov, Gvardeiskaya, 23B
e-mail: ev@cgmnir.ru

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