Wyniki wyszukiwania - BazTech

Ograniczanie wyników

Znaleziono wyników: 3

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: central Iran

Sortuj według:

Ogranicz wyniki do:

Biostratigraphy, microfacies, and reservoir quality of the Oligocene Qom Formation (Kharzan Section, north-west of Ardestan, central Iran)

Arani Asma Aftabi, Ashouri Ali Reza, Daneshian Jahanbakhsh, Ghaderi Abbas, Wood David A.

Geological Quarterly

2023

Vol. 67, No. 3

art. no. 23

The central Iran Basin is a region with unique environmental characteristics in which the Late Paleogene–Early Neogene benthic foraminifera display distinctive distributions and abundances that can assist in identifying the intervals with the best reservoir potential. Lipidocyclinid and miogypsinid zonal marker taxa in this region can be correlated with those in the SBZ23 region (European Basin), indicating an Oligocene (Chattian) age. With sedimentation of continental strata of the Upper Red Formation following the marine succession of the Qom Formation, it seems that the last Tethyan marine transgression in the Ardestan region in central Iran occurred in the Oligocene, and the Tethyan seaway was permanently closed during the Miocene. Seven carbonate microfacies and marl or silty marl facies were identified in the study area based on field investigations, textural analysis and faunal assemblages. These microfacies were deposited on an open-shelf carbonate platform in lagoonal, patch-reef, and open-marine belts that effectively define both inner and middle-shelf environments. Micritization, cementation, mechanical and chemical compaction, dissolution and fracturing are the most important diagenetic processes controlling reservoir quality in the Qom Formation. The investigation of these processes in the facies of the Qom formation in the Kharzan section revealed that intervals associated with shallow lagoonal depositional environments display better reservoir quality than other formation intervals, due to dissolution and fracturing.

Reconstruction of the depositional sedimentary environment of Oligocene deposits (Qom Formation) in the Qom Basin (northern Tethyan seaway), Iran

Safari Amrollah, Ghanbarloo Hossein, Mansoury Parisa, Esfahani Mehran Mohammadian

Geologos

2020

Vol. 26, No. 2

93--111

During the Rupelian–Chattian, the Qom Basin (northern seaway basin) was located between the Paratethys in the north and the southern Tethyan seaway in the south. The Oligocene deposits (Qom Formation) in the Qom Basin have been interpreted for a reconstruction of environmental conditions during deposition, as well as of the influence of local fault activities and global sea level changes expressed within the basin. We have also investigated connections between the Qom Basin and adjacent basins. Seven microfacies types have been distinguished in the former. These microfacies formed within three major depositional environments, i.e., restricted lagoon, open lagoon and open marine. Strata of the Qom Formation are suggested to have been formed in an open-shelf system. In addition, the deepening and shallowing patterns noted within the microfacies suggest the presence of three third-order sequences in the Bijegan area and two third-order depositional sequences and an incomplete depositional sequence in the Naragh area. Our analysis suggests that, during the Rupelian and Chattian stages, the depositional sequences of the Qom Basin were influenced primarily by local tectonics, while global sea level changes had a greater impact on the southern Tethyan seaway and Paratethys basins. The depositional basins of the Tethyan seaway (southern Tethyan seaway, Paratethys Basin and Qom Basin) were probably related during the Burdigalian to Langhian and early Serravallian.

Space Partitioning among Two Sympatric Species, Sand Cat (Felis margarita) and Rüppell's Fox (Vulpes rueppellii), in a Desert Landscape in Central Iran

Feizabadi H. A., Naderi M., Ashrafi S., Hemami M. R.

Polish Journal of Ecology

2018

Vol. 66, nr 2

194--204

This study evaluates and compares habitat preferences and spatial niche breadth and overlap between two sympatrically occurring species, the sand cat (Felis margarita) and Rüppell's fox (Vulpes rueppellii), in a desert landscape of central Iran. A field survey from 2014 to 2016 was conducted to collect occurrence points for the two species as well as to identify their structural characteristics of used habitats in the occurrences points. Jacobs' index as a measure of habitat preference, Shannon and Levins' indices as measures of niche breadth, MacArthur, Levins and Pianka's indices as measures of niche overlap were calculated and interpreted. The results of this study showed that the sand cats are specifically restricted to sand dune and sabulous habitat type, whereas Rüppell's foxes have wider ecological amplitude. Sand cats only prefers sand dunes while Rüppell's foxes were found to prefer foothills, badlands, and sand dunes. Rüppell's foxes therefore had a wider niche breadth compared to the sand cats. The asymmetric MacArthur and Levins indices yielded a higher value of niche overlap for the sand cats compared to Rüppell's foxes, while the symmetric Pianka's measure of niche overlap was relatively high for both species. Such habitat preference and niche segregation between the two species may be a result of their feeding habits or the physical protective structure of their habitats attributes.