The fluid saturation palette development using modern core photo processing algorithms

UDK: 622.276.011.431.3:550.822.8

DOI: 10.24887/0028-2448-2024-7-75-77

Key words: processing photographs of a whole core, fluid saturation probability curve, saturation palette, Khamakinsky horizon, 3D core photography, scan of core photographs

Authors: E.Yu. Ilina (Tyumen Branch of SurgutNIPIneft, Surgutneftegas PJSC, RF, Tyumen), A.V. Kondakova (Tyumen Branch of SurgutNIPIneft, Surgutneftegas PJSC, RF, Tyumen), E.M. Pinigina (Tyumen Branch of SurgutNIPIneft, Surgutneftegas PJSC, RF, Tyumen), D.A. Kaukov (Tyumen Branch of SurgutNIPIneft, Surgutneftegas PJSC, RF, Tyumen)

Terrigenous reservoirs of Eastern Siberia have a
number of specific features and difficulties in studying. In this paper,
attention is paid to ambiguity of the fluid saturation definition while working
with photographs of a whole core in ultraviolet light. Intervals of reservoir
rocks glowing in ultraviolet light during the well production tests can result
in both moisture-free and producing oil inflow. The project was carried out
using 50 wells with core sampling from the Khamakinsky horizon. The developed workflow
made it possible to define the light intensity range of values at which,
probably, one or another hydrocarbon inflow will be received: gas
(gas-condensate), oil, mixed saturation in different combination. As a result,
we get the saturation palettes catalog as an additional source of information.
Processing photographs of a whole core in daylight makes it possible to
additionally determine the glow intervals of rocks lithological inhomogeneity
(foci of anhydritization). Thus, terrigenous reservoirs intervals of mineral
glow are excluded from the fluid saturation probability curve. To solve
operational issues and predict development indicators for complex and fractured
reservoirs, Surgutneftegas PJSC carries out 3D photography and visualization of
a whole core column. Based on the scan of a whole core photographs, the fluid
saturation probability curve is also calculated. The results are imported into
permanent geological models. Depending on the production objective, a
specialist can create a 3D cube of the fluid saturation probability. The
results of created fluid saturation probability curve were compared with the
specific electrical resistivity values, which were measured on core samples and
the specific resistivity curve along wellbore. As a result, well test intervals
choice in exploratory wells drilling process became more successful. Further
prospects for the development