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stress. The former is supported by continuously progressing increase in the
intensity of AHFP manifestations with increasing clay content, thickness
and nonuniformity of the section (they determine their optimum preser-
vation conditions in geological time 11 ). The latter is expressed in the asso-
ciation between zones of maximum areal development and intensity of
abnormality manifestations and the areas of maximum contrast in neotec-
tonic processes (mud volcanism, diapirism, tectonic motions of different
directions and signs, vertical fluid migration, etc.).
Other AHFP's particulars in the PT-KT are:
t Their common association with most faulted crestal areas of
the local highs;
t Significant differentiation of abnormality parameters
between individual fault blocks.
t Decrease in value of these parameters in the direction of
subsided areas of individual structures.
t Continuous spatial association with geotemperature and
hydro-geochemical anomalies formed as a result of vertical
fluid migration from the underlying stratigraphic complexes
(Griroriants, Muradian and Guseinov, 1968; Durmishyan,
Muradian and Rachinsky, 1972; Durmishyan, Muradian and
Rachinsky, 1980; Shuvalov, 1977; Rachinsky, 1989).
Noteworthy in this connection is common mosaic nature in the distri-
bution of initial formation pressure over the area of individual structures:
usually its value is substantially different in the adjacent fault-blocks. This
appears in the most contrasting form in the fields of the northern anticlinal
zones in the Baku Archipelago (Sangachaly-More - Duvanny-More -Bulla
Isl., Bulla-More prospects) and on the structures in the Turkmen part of
the Apsheron-Balkhan area: Livanov Bank East (Magtymguly), Barinov
Bank (Diyarbekir), Zhdanov Bank (Djigalybeg), Gubkin Bank (Garagel-
Deniz) and LAM Bank (Djeitun).
Abnormal pressure is mostly absent between the structures (Apsheron
Peninsula) or is significantly lower than over the highs (Lower Kura
Depression, Baku Archipelago). Typical example is the data about outside-
the-oil-outline productive horizons at the Janub prospect (Yuzhnaya). The
prospect is located in the direction of a drastic PT subsidence southwestward
11 Obviously, the AHPP and AHFP generation mechanisms must be continuously
operating, i.e., the abnormality generation must compensate its natural relaxation.
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