Estimation of Free and Bound Water Balance in Productive Series (Ps) within the Western Part of South Caspian Basin

Abdullayev, Elshan ^1
1 Azerbaijan State Oil Academy, Baku, Azerbaijan.

Evaluation of free and bound water balance in sedimentary rocks has an important significance in the assessment of subsurface formation water and in explaining the reasons for ARP and APP in Productive Series within South Caspian Basin.

Evaluation of free and bound water balance in reservoir rocks was carried out in two structures located on the western part of Absheron and Baku archipelago. These structures differ in their tectonic setting and geothermal conditions as well as lithological composition. After delineation of the study area and determination of volume of productive horizons in these structures, initial free and bound water volumes were estimated. Estimated initial and bound water volume is 8.025 x 103 km3. Today`s remaining quantities of free and bound water constitute 4.425 x 103 km3. Only 40% of formation water was released.

In order to estimate initial and bound water content of Productive Series Quantity method was used. Initial average porosities of shales and sandstones were taken as 75% and 40%, respectively. Compaction ratios of shales and sands are 1.5 and 2 respecively. Average water saturation of sandstones 0.28 and shales 0.35.

Determination of free and bound water content in sedimentary rocks allows us to estimate the volume and origin of subsurface water and reasons of the formation ARP and APP in productive series of western boart within South Caspian.

AAPG Search and Discovery Article #90090©2009 AAPG Annual Convention and Exhibition, Denver, Colorado, June 7-10, 2009