Joint reports


Biostratigraphic and stratigraphic atlas of the Cretaceous, Paleogene, Neogene and Quaternary strata of Azerbaijan and the South Caspian Basin


  • The executive companies: GIA / ARCO / Chevron /
    Conoco / Mobil / Unocal
  • The year of publication: March 1997
  • Code: -
  • Volumes: total 1
    volumes with appendixes in same amount: 1




EXECUTIVE SUMMARY


This report presents the results of a joint study between the Geology Institute of the Azerbaijan Academy of Sciences (GIA) and the BP and Statoil Alliance to investigate the remaining prospectivity within the essentially Pliocene "Productive Series" succession of Azerbaijan.


This study was conceived in early 1996, when there was a definite need for a document discussing the biostratigraphy and stratigraphy of the Mesozoic and Cenozoic rocks of the South Caspian Basin. The last major work of this kind was published in the former Soviet Union more than 20 years ago. With ever increasing hydrocarbon exploration and development activity in onshore and offshore Azerbaijan and the surrounding Caspian area, there was opinion there could be offered important biostratigraphic and stratigraphic information which would be useful to the foreign oil campanies active in the region. A consortium of five companies (Arco, Chevron, Conoco, Mobil, and Unocal) supported this study, which lasted from May, 1996, to February, 1997.


There was decided to limit the stratigraphic coverage of this study to the Cretaceous, Paleogene, Neogene and Quaternary (Pleistocene). Each of the main suites, series, horizons, and beds which comprise this interval is discussed in the text and summarized in charts and text figures for various areas of Azerbaijan and the South Caspian Basin. Sources of information for this report inlcude previoulsy published articles by a variety of authors from our literature collection, our own previously published and unpublished work, and our microfossil analyses of a new sample set selected by the supported companies. The primary objectives of this study include: (1) biostratigraphic, stratigraphic, and chronostratigraphic information, data, and characterization of the units, including critical coments regarding reworked (recycled) fossil assemblages; (2) important fossil zonations; (3) correlations of Neogene units in Azerbaijan, the Caspian Sea, and Turkmenistan; (4) paleoenvironmental discussions and paleogeographic reconstructions; and (5) photographic documentation (62 plates) illustrating the important fossil assemblages upon which much of this and other biostratigraphic work is based.


There are also included the microfossil analyses of a new sample set made available to and selected by the participating companies for this project. The sample are from cores of wells in the Absheron archipelago, Absheron sill, Baku archipelago, and Lower Kura petroleum province.


The primary microfossils discussed and illustrated in this study are calcareous nannofissils, ostracods, and foraminifera. Other fossil groups referenced and illustrated include mollusks (gastropods and pelecypods), diatoms, radiolarians, fish otoliths, charophyte algae, and palynomorphs (spores, pollen, and dinocysts). Sixty-two photographic plates have been assembled for reference. Lists are provided for all fossil included on the plates, organized by fossil groups and geologic periods.


In Azerbaijan and the South Caspian Basin, the lithostratigraphic unirs are typically reffered to in a variety of ways, including suites (e.g. Maykop suite), horizons (e.g. Chokrak Horizon), and beds (e.g. Aucelinian Beds). These terms had been retained in this Atlas because of their common usage throughout the literature. There was not attempts to replace them with the generally equivalent western lithostratigraphic terms of groups, formations, and members. the reader should also keep in mind that some chronostratigraphic stage names (e.g. Sarmatian, Meotian, Pontian) have been historically used in a lithostratigraphic sense in this region.


There also included a large regional map of the South Caspian Basin which shows thegeneral areas mentioned in the text (e.g. PriCaspian-Kuba area; Shemakha-Gobustan area). The approximate locations ofmost of the mentioned oil fields and structures, as well as villages and towns, are indicated by black dots.


CONTENTS


Acknowledgements


Introduction (TAB 1)

Map


Cretaceous (TAB 2)

Introduction


Lower Cretaceous

Babadag Suite
Kaytar Suite
Khalchay Suite
Septarie Suite
Khanagin Suite
Altyagach Suite
Kululin Sandstone
Aucelian Beds


Upper Cretaceous

Kemishdag Suite
Zorat Beds
Kemchy Suite
Yunusdag Suite
Agburun Suite


Cretaceous Text - figures (C1 - C4)


Paleogene (TAB 3)

Introduction
Ilkhidag Suite
Sumgait Suite
Koun Suite


Paleogene Text - figures (P1 - P3)


Neogene (TAB 4)

Introduction
General Overview
Maykopian Suite
Tarkhanian Horizon
Chokrakian Horizon
Karaganian Horizon (Diatom Suite-D1)
Konkian Horizon (Diatom Suite-D2)
Sarmatian Stage (Diatom Suite-D3)
Meotian Stage (Diatom Suite-D4)
Pontian Stage
Productive Series
Akchagagylian Suite


Neogene Text - figures (N1 - N9)


Neogene Charts (N1 - N3)


Quaternary (TAB 5)

Introduction
Apsheronian Stage
Pleistocene


Newly analyzed sample set (TAB 6)

Introduction
Sample set
Calcareous nannofossils analyses
Ostracods, foraminifera, misc.fossils analyses


Photographic plates of key fossils (TAB 7)


Cretaceous (Plates 1-5)

Lower Cretaceous
Upper Cretaceous


Paleogene (Plates 6-25)

Paleocene
Lower Eocene
Middle Eocene
Upper Eocene
Oligocene (Maykopian)


Neogene (Plates 26-54)

Miocene (Tarkhanian-Chokrakian)
Miocene (Doiatom Suite)
Miocene (Karaganian-Konkian)
Miocene (Sarmatian)
Miocene (Meotian)
Miocene (Pontian)
Productive Series
Upper Miocene (Lower Productive Series)
Lower Pliocene (Upper Productive Series)
Upper Pliocene (Akchagylian)


Quaternary (Plates 55-62)

EoPleistocene (Apsheronian)
Lower Pleistocene (Bakunian)


Microfossil Lists

Calcareous nannofossil
Ostracods
Foraminifera
Otoliths
Spores and pollen
Diatoms


References (TAB 8)