Surgil ESIA Report - Volume III - EKN

“O’ZLITINEFTGAZ” PC
PFS “Surgil field complex costruction with valuable
components retrieval”
Sandstones are greenish-grey, rare dark grey, aleuric, mainly fine-grained, quartzfeldspar,
glauconitic, micaceous, with concretions of phosphorite, with rare large fragments
of the charred plant residues. Sandstones possess good filtration-capacitance properties -
values of porosity reach 28%, and permeability 90-1950m/darcy.
Sands are glauconitic, quartz, micaceous. Siltstones are quartz-glauconitic,
micaceous, with concretion of the iron and siderite.
Clays are dense, dark grey, horizontally-microlayered, with accumulation of
phytodetritus, fauna and contractions of phosphorite.
Thickness of the deposits is 160m-179m.
Turon - К 2 t is presented by layers of terrigenous rocks of sea genesis. Silt-clay rocks
are prevailing in the bottom part of the cross-section and are connected with transgressive
cycle of sediment accumulation, in the top there is increases the content of sand and
sandstones. Lithologically it is dark-greenish-grey sands and sandstones, weak slightly
consolidated, micaceous with calcinated-clay cement. Siltstones and clays are greenishgrey,
fat by touch, contain the charred plant residues, mica, quartz.
There is characteristic for the turon deposits the large content of glauconite, and in
the basis of cross-section there are meet the concretion of phosphorite. Thickness of the
turon deposits is 174-175m.
Senon - К 2 sn. The deposits of senon uplayer are widely developed in Aral-Ustyurt
region. To bottom boundary of senon there are dated to intervals in sediment accumulation,
expressed in absence of cognac layer. To upper boundary there are also dated to washouts
and intervals and there is registered reduction of thickness or absence of the deposits of the
Danish layer.
The deposits of campan and Maastricht layers are bedded conformability on the rocks
of santon layer and are presented mainly by light grey, greenish-grey, dense, massive marls
with interlayers of chalklike limestone and marls with pyrite and fragments of pelesypod,
belemnites, foraminifer. Formation of the senon marls occurred in sea conditions under
rather stable sedimentation process.
Thickness of the senon deposits is 365-368m.
Danish layer - K 2 d. The deposits of the Danish layer are bedded nonconformity on
the Maastricht deposits. Their thickness is 12-15m. litholigically they are presented by
greenish-grey, marly, sandy limestone with fragments of brachiopods, pearlweeds and
foraminifers. There are plant residues on which the pseudomorphoses of pyrite are
developed.
Kainozoic group - Kz
Palaeogene system - Р
The palaeogene deposits with washout are bedded on the deposits of chalk and are
presented by three sections.
Volume 2. Part 1. EIS Project for Surgil field construction
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