42 
arenaria, M. scabrosa, M. sulcata, Navicula lyra ssp. elliptica, 
Nitzchia cocconeiformis, Rhopalodia  parallella, — Surirella 
striatula, Terpsinoe musica and Triceratium sp. Campylodiscus 
noricus, C. noricus ssp. hibernica, Diploneis domblittensis, D. 
rombica, Melosira arenaria, M. scabrosa, M. sulcata and 
Rhopalodia parallella are exclusively fresh-water forms, while the 
remainder are quasi-marine. 
The Akchagyl Beds of Northern Iran can be correlated with 
the stratotypical Akchagylian on ostracod evidence (Faridi, 
1964; St6cklin & Setudehnia, 1971, 1972). Various volcanics in 
Central Iran can also be tentatively correlated with the 
Akchagylian (St6cklin & Setudehnia, op. cit.). 
Nannopalaeontology. Stratigraphically significant calcareous 
nannofossils recorded by Semenenko & Lulieva (1982) from the 
Akchagylian include Discoaster brouweri (NN8?-NN18) (no 
younger than 1.89Ma), D. pentaradiatus (NN9?-NN17) (no 
younger than 2.33-2.43Ma) and Reticulofenestra 
pseudoumbilica (NN7?-NN15). These are similar to nannoflora 
found in the Kuyalnikian of the Black Sea region by Semenko & 
Pevzner (1979), and suggest a link between the two basins at this 
time. 
Palynology. Only non-age-diagnostic palynomorphs have been 
recorded from the Akchagylian. Pollen spectra from 
‘Cryo’-SCT14 (and ‘Thermo’-SCT15) are characterised by high 
incidences of Abies (fir), indicating a forested hinterland similar 
to that of the present-day taiga, and a cool, wet climate 
(Bludorova et al., 1987). Those from ‘Thermo’-SCT13 are 
characterised by Abies (fir), Acer (maple), Carpinus (hornbeam) 
and Ulmus (elm), indicating a warmer climate (Bludorova et al., 
op. cit.). Pollen spectra from “Cryo’-SCT14 in the Volga-Urals 
Region are characterised by relatively high incidences of 
Lycopodiaceae (club-mosses), again indicating a cool, wet 
climate (Yakhimovich et al., 1965, 1983, 1984). Pollen spectra 
from ‘Cryo’-SCTs 12 and 10 are characterised by alternations of 
Alnus (alder), Betula (birch) and Pinus (pine), indicating a cool, 
dry climate, and Tsuga (hemlock), indicating a warmer, wetter 
climate (Ananova, 1974; Bludorova et al, 1987). Those from 
‘Thermo-SCT11 in the Volga Basin are characterised by 
relatively high incidences of Tsuga (hemlock) (Zhidovinoy et al., 
1987). Pollen spectra from the undifferentiated Akchagylian of 
the Tersko-Sunzhenskii Region are characterised by high 
incidences of broad-leaved tree taxa such as Fagus (beech) and 
Quercus (oak), indicating a forested hinterland similar to that of 
the present-day taiga (Broad-Leaved Forest Zone), and a 
warm-temperate climatic regime (Naidina, 1988). 
Apsheronian 
The Apsheronian takes its name from the Apsheron Peninsula in 
Eastern Azerbayan (Likharev, 1958). It appears equivalent to 
the Gurian of the Black Sea (Pleistocene). Zubakov & 
Borzenkova (1990) calibrate it against magnetostratigraphic 
polarity epoch 2 (Matuyama). The Apsheronian is essentially 
regressive in character. Marine connections between the 
Caspian and the Black Sea were probably only intermittently 
developed. 
Details of Apsheronian stratigraphy have been discussed by 
Livental (1929), Sultanov (1964), Kuliyeva (1968), Ushakova & 
Ushko (1971), Azizbekov (1972), Lupov et al. (1972), Ali-Zade 
(1973), Ivanova (1985), Zhidovinovy et al. (1987) and Mamedova 
(1988). 
Micropalaeontology. Stratigraphically and/or palaeoenviron- 
R.W. JONES AND M.D. SIMMONS 
mentally significant ostracods recorded by Kuliyeva (1968) and 
Mamedova (1984, 1988) from the Apsheronian of the Baku 
Archipelago in Azerbaijan include Bakunella dorsoacuata, 
Candona_ albicans, Caspiocypris lyrata, C. rotulata, C. 
sinistrolyrata, Caspiolla acronasuta, C. gracilis, Eucypris 
membranae, Leptocythere andrusovi, L. caspia, L. fragilis, L. 
multituberculata, L. propinqua, L. quinquetuberculata, L. 
turquianica, L. verrucosa, Loxoconcha eichwaldi, L. gibboida, L. 
impressa and  Trachyleberis azerbaidzhanica. Bakunella, 
Caspiolla, Leptocythere, Loxoconcha and Trachyleberis are 
quasi-marine forms, while Candona, Caspiocypris and Eucypris 
are fresh-water (see, for instance, Yassini, 1986). At least six 
assemblage zones can be recognised on the basis of ostracods 
(D.N. Mamedova, pers. comm., 1994). These will be discussed in 
a forthcoming paper (Mamedova, in press) (see also Mamedova, 
1988). 
Stratigraphically and/or palaeoenvironmentally significant 
diatoms recorded by Ushakova & Ushko (1971) from the 
Akchagylian to Apsheronian of the Krasnovodsk Peninsula in 
Western Turkmenia are listed under ‘Akchagylian’ above. They 
include exclusively fresh-water, fresh-water to brackish, and 
brackish to near-normal marine forms. 
The Apsheron Beds of Northern Iran can be correlated with 
the stratotypical Apsheronian on ostracod evidence (Faridi, 
1964; Stocklin & Setudehnia, 1971, 1972). 
Palynology. Only non-age-diagnostic palynomorphs have been 
recorded from the Apsheronian. Pollen spectra described by 
Ivanova (1985) from the Apsheronian of Western Turkmenia 
and by Zhidovinov et al. (1987) from the Apsheronian of the 
Volga Basin are characterised by relatively high incidences of 
non-tree taxa. This indicates an open, sparsely forested 
hinterland similar to the present-day steppe or forest-steppe, and 
a cool-temperate climatic regime. 
Bakunian 
The Bakunian takes its name from the city of Baku in Eastern 
Azerbaijan (Likharev, 1958). It appears equivalent to the 
Chaudian of the Black Sea (Pleistocene). Zubakovy & 
Borzenkova (1990) calibrate it against magnetostratigraphic 
polarity epochs 2 (Matuyama) to | (Brunhes). 
Details of the Bakunian stratotype have recently been 
discussed by Mamedova (1984, 1985, 1993, and in press) and 
Aliyulla et al. (1985). | Stratigraphically and/or 
palaeoenvironmentally significant ostracods recorded by 
Aliyulla et al (op. cit.) include Bakunella dorsoacuata, 
Caspiocypris filona, Graviacypris elongata, Leptocythere 
delicata, L. lunata, L. propinqua, Loxoconcha endocarpa, 
Pseudostenocypria asiatica and Xestoleberis ementis. Bakunella, 
Graviacypris, Leptocythere, Loxoconcha and Xestoleberis are 
quasi-marine forms, while Caspiocypris and Pseudostenocypria, 
are fresh-water (see, for instance, Yassini, 1986). Four 
assemblage zones can be recognised on the basis of ostracods 
(Mamedova, in press). 
The Baku Formation of Northern Iran can be correlated with 
the stratotypical Bakunian on ostracod evidence (Faridi, 1964; 
Stocklin & Setudehnia, 1971, 1972). 
Khazarian, Girkan and Khvalynian 
The Khazarian takes its name from an ancient tribe who lived in 
the area between the Don and Volga Rivers, and the Girkan(ian) 
and Khvalynian take theirs from ancient names for the Caspian 
