Page 262 - Geology and Geochemistry of Oil and Gas

MODELS OF STATIC GEOLOGIC SYSTEMS 227

Fig. 11.10. Histograms of crude oil density (a), content of resins plus asphaltenes (b), and ‘‘benzine’’
(gasoline) content (c) in the crude oils of Neft Dashlary Field of Azerbaijan (after Buryakovsky et al.,
2001). Formations (from section top to bottom): 1: – Balakhany, 2 – Fasila, 3 – Nadkirmaku sandy
(NKP), 4 – Kirmaku (KS), 5 – Podkirmaku (PK), 6 – Kala (KaS).

formations of the stratigraphic section of Neft Dashlary Field. With increasing
stratigraphic depth, the density of crude oil increases. These trends, however, are not
present in the upper formations. The increase in the oil density in the upper for-
mations is related to the oxidation of oil by near-surface agents, which increases the
content of asphaltenes plus resins and decreases the gasoline content.

11.2.2.2. Two-dimensional models
11.2.2.2.1. Reservoir rocks. Correlations among the reservoir-rock properties in
the form of average (orthogonal) regression lines are shown in Figs. 11.12 and 11.13
for two regions of Azerbaijan: (1) Baku Archipelago and South Absheron Offshore
Zone and (2) the Lower Kura Depression. The correlation coefficient (r) is presented