The results of integrated sedimentology,petrography,and petrophysical study of the Upper Devonian(Middle Famennian)Dankovo-Lebedyansky carbonates from Southeast Tatarstan of the Volga-Ural Basin revealed a variety of ...The results of integrated sedimentology,petrography,and petrophysical study of the Upper Devonian(Middle Famennian)Dankovo-Lebedyansky carbonates from Southeast Tatarstan of the Volga-Ural Basin revealed a variety of microfacies and diagenetic events that impacted the reservoir quality.Although our earlier study documented microfacies analysis and depositional environments,none of the studies focused on diagenesis,microfacies interaction,and their controls on the studied sediment's reservoir quality.Based on petrographic and microfacies analyses,the seven identified microfacies types are peloidal grainstone MF 1,cemented bioclastic peloidal grainstone MF 2,echinoderm-concentrated packstone MF 3,algae packstone MF 4,bioclastic wackestone MF 5,whole-fossil wackestone MF 6,and dolomite MF 7.For the investigated sediments,a gently deepening carbonate ramp depositional model with an inner,middle,and outer ramp setting is proposed.The observed diagenetic events in this study include micritization,calcite cementation(six cement types),dolomitization(six dolomite types),dissolution(fabric and non-fabric-selective dissolution),compaction,and microfracturing.The identified microfacies were classified into three distinct classes based on their petrophysical characteristics.MF 1 and MF 7 are microfacies types with the best reservoir quality.MF 3 and MF 4 are microfacies types of moderate reservoir quality.MF 2,MF 5,and MF 6 are microfacies types with poor or non-reservoir quality.Calcite cementation,micritization,and compaction are the primary diagenetic modifications responsible for porosity reduction.Moldic pores created by dissolution are a significant porosityimproving process.Porosity is locally enhanced by stylolite and microfractures.Dolomitization improved reservoir quality by creating intercrystalline and vuggy porosity.Understanding the impact of microfacies and diagenesis on reservoir quality is crucial for understanding reservoir properties in nearby fields with similar settings.展开更多
Typha shuttleworthii is the semi-aquatic plant in the modern areal which embraces mainly the ocean districts of Europe. The eastern border of the area of this species is located in Eastern Europe on the territory of V...Typha shuttleworthii is the semi-aquatic plant in the modern areal which embraces mainly the ocean districts of Europe. The eastern border of the area of this species is located in Eastern Europe on the territory of Vyatka-Kama Cis-Urals (VKCU). Almost everywhere species is considered rare and is included in the Red Data Books in many European countries. However, on the territory of Russia, T. shuttleworthii is not protected. The rarity of this species makes it necessary to study its natural populations for their protection. In the paper, we present the materials on some biological and ecological features of the Typha shuttleworthii, growing on the territory of Vyatka-Kama Cis-Urals, where the species is represented by its extreme eastern populations. This species is offered to the protection on the territory of the European part of Russia within the Republic of Tatarstan and Udmurtia.展开更多
基金supported by the Ministry of Science and Higher Education of the Russian Federation under agreement No.075-15-2022-299 within the framework of the development program for a world-class Research Center“Efficient development of the global liquid hydrocarbon reserves”.
文摘The results of integrated sedimentology,petrography,and petrophysical study of the Upper Devonian(Middle Famennian)Dankovo-Lebedyansky carbonates from Southeast Tatarstan of the Volga-Ural Basin revealed a variety of microfacies and diagenetic events that impacted the reservoir quality.Although our earlier study documented microfacies analysis and depositional environments,none of the studies focused on diagenesis,microfacies interaction,and their controls on the studied sediment's reservoir quality.Based on petrographic and microfacies analyses,the seven identified microfacies types are peloidal grainstone MF 1,cemented bioclastic peloidal grainstone MF 2,echinoderm-concentrated packstone MF 3,algae packstone MF 4,bioclastic wackestone MF 5,whole-fossil wackestone MF 6,and dolomite MF 7.For the investigated sediments,a gently deepening carbonate ramp depositional model with an inner,middle,and outer ramp setting is proposed.The observed diagenetic events in this study include micritization,calcite cementation(six cement types),dolomitization(six dolomite types),dissolution(fabric and non-fabric-selective dissolution),compaction,and microfracturing.The identified microfacies were classified into three distinct classes based on their petrophysical characteristics.MF 1 and MF 7 are microfacies types with the best reservoir quality.MF 3 and MF 4 are microfacies types of moderate reservoir quality.MF 2,MF 5,and MF 6 are microfacies types with poor or non-reservoir quality.Calcite cementation,micritization,and compaction are the primary diagenetic modifications responsible for porosity reduction.Moldic pores created by dissolution are a significant porosityimproving process.Porosity is locally enhanced by stylolite and microfractures.Dolomitization improved reservoir quality by creating intercrystalline and vuggy porosity.Understanding the impact of microfacies and diagenesis on reservoir quality is crucial for understanding reservoir properties in nearby fields with similar settings.
文摘Typha shuttleworthii is the semi-aquatic plant in the modern areal which embraces mainly the ocean districts of Europe. The eastern border of the area of this species is located in Eastern Europe on the territory of Vyatka-Kama Cis-Urals (VKCU). Almost everywhere species is considered rare and is included in the Red Data Books in many European countries. However, on the territory of Russia, T. shuttleworthii is not protected. The rarity of this species makes it necessary to study its natural populations for their protection. In the paper, we present the materials on some biological and ecological features of the Typha shuttleworthii, growing on the territory of Vyatka-Kama Cis-Urals, where the species is represented by its extreme eastern populations. This species is offered to the protection on the territory of the European part of Russia within the Republic of Tatarstan and Udmurtia.
