Abstract The region of Kyrgyzstan, Tajikistan and Uzbekistan includes five first-order tectonic units with an Early Paleozsoic sedimentary record, comprising North Tien Shan, Karatau Naryn, Turkestan–Alai, Zeravshan–Hissar and the Central Pamirs. Available palaeobiogeographical and palaeomagnetic data suggest that these were widely dispersed in the Ordovician. North Tien Shan, Karatau Naryn, Turkestan–Alai were separate microcontinents located in the low southern latitudes throughout the Ordovician in relative proximity to the western Gondwana margin. Zeravshan–Hissar and the Central Pamirs were also parts of the Gondwana supercontinent but were located in temperate latitudes. The geological literature on the Ordovician of the region is assessed to provide an updated palaeontological record, outline of lithostratigraphy and biostratigraphic correlation based on the International Chronostratigraphic Chart. The Ordovician biostratigraphy of Central Asia is mainly graptolite-based; however, that record is discontinuous, and the absence of detailed faunal logs and lack of monographic studies causes difficulty in precisely locating system and stage boundaries. Although an extensive faunal record has been documented, often it is based on preliminary taxonomical identifications which are not reliable for high-resolution biostratigraphy and tracing biodiversity patterns.

Abstract The passive margin carbonate platform in the Middle Tien Shan rests on Givetian–Frasnian red siliciclastic strata. It evolved from an attached carbonate platform in the Famennian and early Tournaisian to an isolated carbonate platform in the late Tournaisian to early Bashkirian. The open-ocean side of the platform was reef-rimmed, whereas the continental side was both reef- and shoal-rimmed. Platform interiors exhibit low-energy facies during the Famennian to early Visean and high-energy facies during the late Visean to Bashkirian. Eustatic sea-level rises in the middle Tournaisian, early Visean and near the Visean and Serpukhovian boundary caused major reorganizations in platform architecture. Deformation in the middle Bashkirian reflects the onset of a convergent margin. Flexural loading by an orogenic thrust wedge controlled basin subsidence along the southern edge of the Middle Tien Shan in the Late Pennsylvanian to Asselian. Cessation of deposition in the Asselian followed by folding and granitoid plutonism reflects the onset of a rigid collision. Devonian to Permian carbonates represent outcrop analogues of coeval oil- and gas-rich carbonate platforms in the North Caspian basin and can be used for comparative and predictive sedimentological studies. Palaeozoic carbonate reservoir facies may host subsurface Cenozoic oil fields in the Fergana Basin.