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Assessment of detection capability of Mongolian seismic station
Get PDFAssessing the sensitivity of Mongolia’s seismic stations and determining the minimum threshold for earthquake detection provide essential information for researchers. To evaluate the detection capacity of these stations, each station calculates its self-noise level using the 90th percentile value of the probability density function (PDF) of the power spectral density (PSD), based on data acquired between January 2018 and May 2021. To simulate earthquake detection in Mongolia, we implemented a grid where each point represents an earthquake epicenter. These points are spaced at 10 km intervals. The detection of a seismic wave is determined based on an amplitude attenuated by distance, which must be at least three times higher than the self-noise level of the station. For a point to be considered detectable, at least four stations must register the seismic wave under these conditions. Using these criteria, a detection capability map is generated to assess the overall detection capacity of the network. From the resulting analysis, it can be concluded that the seismic network in Mongolia is capable of detecting earthquakes with a magnitude of 1.8 across the country. In the western and central regions, where station density and sensitivity are higher, the network can detect seismic events as small as magnitude 1.4
The relationship between geological features and phase tensor: examples from Mogod an Tsenker study areas
Get PDFThe magnetotelluric phase tensor contains information about the directionality and dimensionality of the study region’s geo-electrical structure. In this context, the phase tensor controls geological faults or fractured zones and homogeneities of the lithology. Although the phase tensor is commonly used for magnetotelluric analysis, it is still poorly introduced in Mongolian case studies. Therefore, this paper introduces the theoretical concepts of the phase tensors and their applications in the Tsenkher and Mogod geothermal regions. For this study, we used magnetotelluric data sets from the previously conducted measurements in 2019 and 2022 at the Tsenkher region and newly measured data at the Mogod region in 2024. With this study, we re-analyzed all observed data with advanced approaches to improve data quality, resulting in smooth and clean magnetotelluric impedance tensors being obtained. The impedance tensors were used to estimate the real-valued distortion-free phase tensor at every unique measurement site. We calculate the geo-electrical strike direction from the phase tensor with the Swift angles at every site and dimensionality. As a result, the phase tensors represented the geo-electrical direction and dimension that indicates geological faults and the voluminousness of the massive rocks. Another advantage of this study is providing a developed MATLAB-based code to calculate and plot the phase tensor as a tool to support geoscientists for their future study. In the end, based on the implementation of this research, we conclude that magnetotelluric phase tensor could be used as an efficient tool for geological interpretation for geoscientific studies in the country
Sedimentary basins, hydrocarbons, graphite, coal, and Cu-Au deposits - from Mongolia to the Pacific margin: Interplay between the ubiquitous orthogonal fracture network and Global Wrench Tectonics
No full textMongolia is exceptionally rich in coal and copper-gold resources - with world-class deposits like Tavan Tolgoi, Oyu Tolgoi and Erdenet. Thus, the mining industry has a crucial importance for the national economy, yet most of the country remain very underexplored. Within today\u27s global tectonics, an acceptable understanding of metal enrichments - including leaching, the internal hydrostatic-hydraulic pumping system, and surface emplacement mechanisms - has remained unresolved. However, a broader view of the structural situation in the Mongolia-China region shows a close link between orientation of elongate sedimentary basins, important mineral belts, and the fundamental orthogonal fracture/fault system. In the east the tectonic trend is dominantly northeast, while it is northwest in western areas. The main east Mongolian graphite deposits have northeast structural trends like numerous regional Cu and Au belts. A new theory of the earth, Global Wrench Tectonics, offers an exciting approach to better understanding the various facets of Earth\u27s geological history and its surface resources. Earth’s degassing, dynamo-tectonic consequences, inertia-driven crustal wrench tectonics, as well as surface products such as water, hydrocarbons and ore deposits are given a coherent system explanation. Many hydrocarbons are products from the interior of our slowly degassing Earth, with massive hydrocarbon fields such as Songliao and the Yamal megaproject producing from the basement. Crustal thinning in the Songliao region is about the same as in southeast Mongolia, suggesting that they may have had similar degassing and crustal evolution histories. As such, it is not unlikely that the underexplored Mesozoic basins of southeast Mongolia - particularly at the deepest levels and/or in the adjacent crystalline basement - may have important hydrocarbon potential
The Effects of Anthropogenic Loads on Vegetation Cover and Natural Water Quality in the Ugii Lake Basin, Mongolia
No full textThe Ugii Lake Basin, located in central Mongolia, has many natural parks with unique formations and is part of the International Ramsar Wetland Protection Agreement. To establish the "New Kharkhorum" city, it was necessary to plan and evaluate changes to the regional geological environment, including the Ugii Lake Basin. We aimed to assess changes in the vegetation cover, soil, and surface water of the Ugii Lake Basin. Field research, geochemical analysis of soil and surface water, and remote sensing image interpretation methods were used in this study. We interpreted Moderate Resolution Imaging Spectroradiometer satellite data from 2000 to 2022 to investigate changes in vegetation cover. On the basis of this classification, soil and natural water samples were chosen for onsite observations at four locations. As a result, the boundaries of the Ugii Lake Basin have been defined; they are 1017 km long and cover an area of 14,300 km2. Six normalized difference vegetation index categories were identified while the vegetation cover quality in the Ugii Lake Basin was assessed. The pH values of the surface water exceeded the standard by 0.05–0.21 in the area with a high anthropogenic load, whereas the other factors (Ca2+, Mg2+, Na++K+, SO42-, Fe, CI-, CO32-, HCO3-, NO2-, NO3-, and physiochemical parameters) did not exceed the Mongolian National Standard. The pH values in natural water were relatively high near the lake, indicating human activity in the Ugii Lake Basin. Consequently, this should be considered when designing integrated measures to address climate change and anthropogenic impacts in the Ugii Lake Basin
Thermal processing of plastic wastes for fuel
Get PDFPlastic wastes rise annually as a result of the growing demand for synthetic materials, which contributes to their manufacture. There are four main ways to recycle waste polymer, with thermal treatment for fuel being the most favorable to the environment. In this study, the thermal processing of plastic wastes was investigated with an anaerobic pyrolysis apparatus, and their thermal degradation was evaluated by using the thermogravimetric apparatus.Additionally, the elemental composition was determined by an elemental analyzer, n-alkanes were identified by gas chromatography with flame ionization detection/electron capture detector (GC-FID/ECD), and the hydrocarbons functional group was analyzed by Fourier transform infrared spectroscopy (FTIR). We pyrolyzed the most widely utilized polymers, including polypropylene (PP), low-density polyethylene (LDPE), and high-density polyethylene (HDPE), at temperatures as elevated as 500°C to obtain plastic pyrolysis oil (PPO). Then PPO was distilled into initial boiling point (IBP)-200°C (gasoline-like fuel), 200-350°C (diesel-like fuel), and over 350°C fraction (residue), and the technical features of each fraction were compared to the MNS 0217:2006 and MNS 6861:2020 standards. Diesel-like fuel (DLF) derived from LDPE consists of the n-alkane hydrocarbons with C8–C23 identified by flame ionization detection (FID) data; C10–C17 represented more than 80% of them.The hydrotreatment results revealed that the diesel-like fraction\u27s nitrogen (N) and sulfur (S) amounts could have reduced from 0.06% to 0.01% and from 0.78% to 0.29%, respectively. In conclusion, it could be done to generate a product with a more stable hydrocarbon content from plastic wastes for fuel
A new methodology for choosing the efficient and optimal option of renewable energy for local heat supply
Get PDFOne of the tendencies of the power engineering sector in Mongolia is to devise an eco-friendly new technology, and solve the problem of supplying heat from reliable sources to consumers in the centralized rural areas of the country. The soil temperature is divided into four different zones. The soil temperature starts from 1.6 meters for the 4th zone, the southern part like the Gobi provinces of Mongolia, where the soil temperature has never decreased, even in the coldest months of the year. The study compared solar collector systems and heat pump systems and proposed environmentally friendly and economically efficient heating technologies depending on the climatic zones of Mongolia
Refined L^2-decay estimate of solutions to a system of dissipative nonlinear Schroedinger equations
Get PDFWe study the Cauchy problem of a system of dissipative nonlinear Schr¨odinger equations. Our target is to obtain a time-decay estimate of the solutions in without size-restriction on the initial data. By imposing high regularity and rapid spatial decay on the initial data, we find that the -norm of the solutions decays at the rate of as . It is a refined decay-estimate, compared to former works.
Identifying Endometrial Delay Improves Treatment Outcome in Women with Thin Endometrium and Infertility
Get PDFObjective: To determine the impact of endometrial delay on reproductive outcomes.
Method: We enrolled 62 infertility women with thin endometrium pre- and post-study in 2020-2023. Infertile women with an endometrial thickness of <7 mm were included and followed in the study. All participants had endometrial delay determined and adjusted before initial Assisted reproductive technologies (ART). After, infertility treatment was started. ART outcomes were evaluated by endometrial thickness and implantation rate. Endometrial thickness was compared to pre-hormone replacement treatment at 48 and 72 hours post-hormone therapy. Results: The study included 62 women aged 26-45 who were diagnosed with infertility and thin endometrium. Endometrial thickness was sufficiently increased before and after treatment for all participants. Histological analysis diagnosed endometrial delay (not appropriate WOI) in 73.6% of all women. After adjusting the WOI in study participants, there was a statistically significant increase in endometrial thickness post-hormone replacement therapy. The study participants were women who had failed at least one implantation, and the implantation rate after WOI adjustment was 58.5%. Conclusions: In 70% of infertility women, endometrial is delayed. In women with thin endometrium, the precise determination of WOI increases ART treatment outcomes
The Potential Effect of Traditional Herbal Medicine on Bile Flow in CC14-Induced Liver Injury Model
Get PDFObjective: To investigate whether the modified Mongolian traditional medicine Yaman Serdeg-3 (NYS-3) effects the biliary excretion in the carbon tetrachloride-induced liver injury model. Methods: Forty-seven male and female Sprague-Dawley rats were divided into 5 groups: Group I healthy group (n=12); Group II healthy group + NYS-3 (n=9); Group III liver injury model (n=10); Group IV liver injury model + Chinese medicine Hua gan Pian (n=10); Group V liver injury model + NYS-3. Experimental groups II-V, received corresponding medicinal preparations for 2 weeks. The dose of Hua gan Pian (HGP) was 0.046g/ml while the dose of NYS-3 was 2.025g/ml. For the acute induction of liver injury, the rats were orally administered 40% CCl4 in olive oil (4 ml/kg) twelve hours after the last administration of preparations. Results: At the first 15-minute interval, the highest bile flow was observed in Group II rats, which were administered NYS-3. This phenomenon continued at the second 15-minute interval, also. However, at the third 15-minute interval, the bile flow decreased sharply in Group II. On the other hand, in the liver injury model, untreated or pre-treated rats had significantly different bile flows. For example, in the first half of the experiment, both non-treated and HGP pre-treated groups had similar bile flow, while, the group pre-treated with NYS-3 had significantly low bile flow. Then, after 45 minutes of the experiment, the bile flow became similar amounts in both pre-treated groups. Conclusion: We conclude that the NYS-3 administration had increased the bile flow at 3rd 15min of interval, which is higher than positive control group where liver injury model rats received HGP
Invasive Hemodynamic Monitoring and Arterial Blood Gas Exchange During Spinal vs General Anesthesia for Cesarean Delivery in Mongolian Parturient
Get PDFObjective: This study investigated the accuracy and precision of continuous, invasive blood pressure obtained using the arterial line system in patients undergoing cesarean section with spinal and general anesthesia. Methods: A total of 150 parturient women who underwent C-sections from July 1, 2021, to Dec 30, 2023, were divided into two groups: the GA (general anesthesia) group (n=50) and the SA (spinal anesthesia) group (n=100). In this prospective observational study, we measured and compared the changes in hemodynamic fluctuation and arterial blood gas deviations under C-section with either spinal or general anesthesia. Results: One hundred fifty patients were recruited for the study after exclusions, and data were analyzed for 150 patients. There were no significant differences in the time from anesthesia to incision, the operation duration, infused crystalloid volume, blood loss, and urine output. The most frequent complications were surgery hypotension, tachycardia, nausea, and headache in the SA group, and tachycardia, hypertension, in the GA group These complications may cause SA’s impact on the sympathetic nerves, resulting in dilated blood vessels and reflex tachycardia. Conclusion: It has been suggested that the choice of anesthesia technique has a significant impact on hemodynamic stability during cesarean section