The genesis, mineralization, and stratigraphic significance of phosphatic/glauconitic condensed limestone unit in the Manavgat Basin, SW Turkey     

A. Mete zgüner  Baki Varol 《Sedimentary Geology》2009,221(1-4):40-56

A condensed hemipelagic limestone unit with glauconite and phosphate separates a drowned Late Burdigalian carbonate platform from overlying Langhian pelagic mudstones, marls, and calcarenitic tempestites within the Neogene Manavgat Basin of southwestern Anatolia, Turkey. The unit consists of coeval lenticular limestone bodies, between 1 cm and 15 m in thickness, ranging from 10 m to 3 km in lateral extent. The P2O5 content of this limestone ranges from 0.2 to 10% by weight and the iron-oxide, clay, and other metal-oxide contents of this unit substantially exceed those of the underlying and overlying rocks.This condensed stratigraphic unit was deposited on the southwesterly outer shelf portions of drowned horsts that directly faced upwelling currents. The unit displays three main facies: 1) glauconitic phosphate crusts associated with hardgrounds; 2) bedded glauconitic-phosphatic limestones; and 3) glauconitic-phosphatic limestones interbedded with resedimented limestones. Facies (1) forms the thinnest units whereas facies (3) is the thickest, since the thickness and spatial distribution of this facies are related to environmental contrasts caused by block faulting of the underlying carbonate platform.This lithostratigraphic unit of hemipelagic glauconite–phosphate deposition represents an interval of maximum flooding in tectonically active situations and depositional hiatus on submarine highs that separate the carbonate transgressive systems tract from the overlying terigenic tempestite highstand systems tract. This appears to be the sole condensed unit within the Miocene Manavgat Basin; and is here ascribed to a third-order (2.3) eustatic rise in sea level comprising the maximum flooding of the first-order cycle. This is also the time for early–Mid Miocene major changes in Mediterranean climate from tropical to temperate.  相似文献   

Effects of land-based sources on water quality in the Omerli reservoir (Istanbul,Turkey)     

Enis Morkoç  Vildan Tüfekçi  Huseyin Tüfekçi  Leyla Tolun  Fatma Telli Karakoç  Tuğba Güvensel 《Environmental Geology》2009,57(5):1035-1045

The Omerli reservoir is located on the northeastern side of the Istanbul City. It is one of the most important sources of drinking water with a surface area of 23.1 km² and a volume of 220 × 10⁶ m³ in the Marmara Region. Water quality characteristics of the lake investigated from May 2002 to April 2003 enabled us to identify the effect of waste loads on water quality of Omerli Lake. The following parameters were measured in the lake water: temperature (16.1°C), conductivity (250 μS/cm), secchi disk depth (1.9 m), dissolved oxygen (DO) (9.36 mg/L), nutrients [ortho-phosphate (78.9 μg/L), nitrate + nitrite (707.5 μg/L) and ammonia-nitrogen (264 μg/L)], chlorophyll a (9.43 μg/L), total organic carbon (3.33 mg/L), total suspended solids (4.54 mg/L), total poly aromatic hydrocarbon (t-PAH) (0.69 μg/L) and copper (24.5 μg/L). T-PAH (16.5 mg/g-dry-w), Cu (96.5 μg/g-dry-w), organic carbon (org-C) (2.0%) and N (0.44%) were determined in the surface sediment. The values of chlorophyll a and DO in the upper layer were relatively high and low secchi disk depths indicates eutrophic state. There are five channels discharging water, including waste water, into the lake. All channels were sampled during six occasions in order to cover variations between seasons. The following parameters were measured: total organic carbon, total phosphorus, total kjeldahl nitrogen, ammonia and total suspended solids with the flow rates. The Göçbeyli stream has the highest flow into the lake (1.5 × 10⁸ m³/year) but most of the nutrients were discharged from the Pa?aköy channel. It is accounting for 81% of ammonia and 80% of total phosphorus into the lake. Three scenarios were run using AQUATOX model: (1) all existing inflows are discharging into the lake (present situation); (2) none is discharging; (3) all are discharging except the Pa?aköy channel. The first scenario produced concentrations consistent with measurements in the lake. In all stations, a phytoplankton peak value was predicted during November and December 2002, and January 2003. In the second scenario, as expected, a significant decrease in the concentrations was predicted. In the third scenario, a small improvement in the water quality was obtained. To significantly improve the state of the lake, instead of entering Pa?aköy channel, wastewater should bypass the lake.  相似文献   

Landfill Leachate Treatment: A Case Study for Istanbul City     

Cevat Yaman  Huseyin Kurtulus Ozcan  Goksel Demir  Hatice Eser Okten  Senol Yildiz  Asli Coban  Vahit Balahorli 《洁净——土壤、空气、水》2012,40(7):706-711

One of the most important problems arising from landfilling solid wastes is the leachate which contains high amount of pollution. Discharge of leachate without treatment causes negative effects on environmental and public health. In this study, parameters of chemical oxygen demand (COD), total nitrogen (TN), ammonia nitrogen (NH₄‐N), and total phosphorus (TP) were examined in the samples taken from the influent and effluent of leachate treatment plant, where Odayeri landfill leachate is treated. Obtained results showed that the treatment plant, which consisted of preanoxic biological treatment system, ultrafiltration (UF) and nanofiltration (NF) units were operating with high efficiency. Among the examined parameters during study, COD, TN, NH₄‐N, and TP were found to be treated at the rate of 99, 94.5, 99, and 93.8%, respectively. Landfilling is increasing rapidly in the world and this consequently brings the need of leachate treatment facilities. Therefore, this study is considered to be a guide for construction and operation stages of proposed new treatment plants.  相似文献   

Water absorption process effect on strength of Ayazini tuff,such as the uniaxial compressive strength (UCS), flexural strength and freeze and thaw effect     

Mustafa Yavuz Çelik  Huseyin Akbulut  Ayşe Ergül 《Environmental Earth Sciences》2014,71(9):4247-4259

Tuffs have been used as a construction material possibly since ancient times. In Afyonkarahisar, Turkey, there are numerous buildings constructed by tuff. Tuff has been a local construction material, during the Roman, Seljuk and Ottoman periods. Even though tuffs have relatively low durability and low strength values compared to marble, etc., they have survived with no major deterioration failures on many historical buildings. It has also been preferred because of its high porous texture, lightweight and easy shaping and process properties in the building sector. Naturally, it would be easily affected by water and humidity because of its porous structure. However, having this kind of structure leads to poor durability properties due to keeping water in it. The main objective of this study was to evaluate the physical and mechanical properties of the tuff quarried from the region and possible water effect, which may lead to degradation of its strength and durability of the material, thereby shortening the life span of the building structure used. Samples, which were tested after exposing to water and the freeze and thaw effects, were measured at a certain time. In this study, uniaxial compressive strength and flexural strength tests were conducted on test samples. The test results indicate that water may deteriorate the tuff’s strength properties and durability of the materials in due time.  相似文献   

Recurring emergence of the mud islands on shelf of the Arabian Sea along the Makran coast of Pakistan – Historical perspective using remote sensing techniques     

Akhtar M. Kassi  Huseyin Bayraktar  Shuhab D. Khan  Aimal K. Kasi 《Journal of the Geological Society of India》2017,90(2):201-208

Recurring emergences of mud islands on shelf of the Arabian Sea, along the Makran coast of Pakistan are now known to be submarine mud volcanoes. They are expressions of enhanced extrusions of fluidized mud and gases coupled with compressional tectonics in convergent margin settings. Since 1945 the Malan island has emerged four times, and some other mud islands have also been emerging repeatedly, at their own positions.The first known emergence, during November 1945, was concurrent with an earthquake of magnitude 8.0 (M8.0), the 2^nd and 3^rd emergences, in March 1999 and November 2010 respectively, were not related apparently with earthquakes. The 4^th emergence concurred with the Awaran earthquake (M7.7) of 24th September 2013. Landsat images of March 1999 and November 2010 emergences indicate appearance of round-shaped island of 4.4 and 5.2 hectare area, followed by erosion and disappearance. The island was composed of mud breccias and circular vents spewing mud slurry and methane gas.The emergence of Malan island, in March 1999 and November 2010 was compared with earthquake data before and after the emergences. The earthquakes data, two years before March 1999 and November 2010 emergences and two years afterwards, shows correlation with both small and large earthquakes, prior to the emergence, in the radius of over 400 km. It is proposed that mud islands develop in response to the episodes of enhanced mud extrusion, which inturn are related with the enhanced compressional and/or seismic events. These events are followed by periods of relative quiescence characterized by normal activity of mud extrusion and marine erosion.  相似文献