Complex approach in reservoir property prediction and its hydrocarbon saturation Печать

A. KUROCHKIN, Y.U. FEDOROVSKY, B. KUTYCHKIN, I. TANYGIN, YU. MIRZOYAN

LLC Ingeovector, Syntezneftegaz Ltd., Arktikshelfneftegaz Ltd. 
FSUE Arktikmorneftegazrazvedka, LLC Ingeoseis

Reservoir property prediction with selecting collectors of different nature, determination of their capacity end filtrations parameters and petroleum-gas saturation is always a complex task with certain probabilities. 

The success of solving it in many cases depends on the complexities of a particular research object, existence of formal technologies in solving inverse (reverse) dynamic seismic tasks, stage of geological research for a particular object and possibilities of using any additional geological and geophysical information that determine specifics and qualities of certain model based on different physical fields.

The principle of complex use of different physical and mathematical methods in solving prediction tasks increases probability of a particular task. The main methods of complex approach that is used by us are the following:

• The technology uPetroseis" is based on solving tasks of inversion for seismic information into parameters of model of environment under acoustic and упругого approximation based on stochastic algorithms.

• The technology of seismic-acoustic entropy-enthalpy analysis (SAEE) uses a measure of entropy as an indicator of petroleum-gas saturation.

• The technology of spectra-energetic evaluation of seismic record parameters based on cepstral changes. It allows determining non-linear-geological parameters in penetratable environments.

The technology "Petroseis" allows to determine parameters of model in traditional mono-parametric (Vp, Vs, Ap and others), elastic-deformation modular (k, m) and complex parameters (y=Vs/Vp and a - poisson's ratio). They will determine a lithotype and the nature of petroleum-gas saturation.

The entropy analysis, which is done through SAEE, reflects the changes of thermo-dynamic parameters of a section due to processes of fluid dynamic. The measure of entropy, as an indicator of petroleum-gas saturation, depends on volume of capacity space of collectors, parameters of their penetrability and viscosity of saturating fluids.

The technology of spectra-energetic evaluation of seismic record parameters is based on cepstral changes and allows evaluation of changing parameters in wave packs in different parts of spectre and time and parameters of these processes.

The specifics of using the mentioned technologies for terrigenic, carbon and carbon-terrigenic section and respective parameters of collectors, determine the diagnostic of the later ones and the evaluation of their petroleum-gas saturation on qualitative and qualitative levels. Such complex approach in reservoir property prediction was used in seismic-geological situations in several provincial parts of the country, taking into account the specifics of their formation and development. The work results prove effectiveness of such approach in different conditions and situations.

The necessity of using the above approach for Timano-Pehcerskoi petroleum-gas territory is related to the complexity of its tectonic and seismo-facial composition. The presence of wide specter of deposits related to Trias period and presented as sand and clay deposits until low-Devon carbon and carbon-terrigenic deposits, including all specifics of collectors, their epigenetic changes requires specific complex analysis and prediction methods for different strati-graphical sections with related litho-facial conditions and petro-physical section parameters, which are determined by specifics of petroleum-gas saturation.

The mentioned examples of section prediction analyses and its hydrocarbon saturation for island Kolguev and Medinskoi structure shows the difference in approaches in studying objects of different nature, strati-graphic and gipso-metric level, seismo-facial and tectonic conditions.

The comparison of reservoir property prediction results and results of boring data proves the effectiveness of using several technological prediction methods and the necessity of further use of them in Timano-Pechorskoi petroleum-gas province, as well as in other surrounding regions.

ARCTIC SHELF OIL AND GAS CONFERENCE 2004