scholarly journals Clay minerals from rock salt of Bahadur Khel Formation, Eocene, Pakistan

2020 ◽  
Vol 1 (182) ◽  
pp. 87-100
Author(s):  
Yaroslava YAREMCHUK ◽  
Serhiy VOVNYUK ◽  
Mohammad TARIQ

According to studies of the pelitic fraction of the water-insoluble residue of 10 samples of Eocene rock salt of the Bahadur Khel Formation (Pakistan), it was determined that the clay minerals association contains swelling chlorite, chlorite-smectite, illite and kaolinite; chlorite was identified in three samples. Non-clay minerals are represented by quartz, dolomite, less often – magnesite; one sample contains impurities of both carbonates. Swelling chlorite, chlorite and mixed-layer minerals are trioctahedral, and illite and kaolinite are dioctahedral. All identified clay minerals, with the exception of kaolinite, are authigenic. The presence of swelling chlorite in Eocene rock salt is probably caused by changes in the concentration of brines in the basin against the background of complex geological processes of this era (climate change from thermal maximum to global cooling, changes in water circulation in oceans, changes in isotopic composition of carbonates). The association of clay minerals of Eocene rock salt, taking into account the peculiarities of its composition and the presence of swelling chlorite in it, we attributed to that formed during the SO4-rich seawater chemical type. This is also confirmed by two finds of swelling chlorite in the Triassic evaporites (rock salt of the Western Moroccan Basin, Midland marl) described in the literature, which are known to have been deposited from SO4-rich seawater. The presence of kaolinite in almost all samples is caused by its largest accumulation in sediments of this time period – terrigenous kaolinite came in large quantities from dry land and did not transform even at the stage halite precipitation. Full Text Keywords clay minerals, swelling chlorite, rock salt, Eocene, Bahadur Khel Salt, Pakistan.

2017 ◽  
Vol 23 (2) ◽  
Author(s):  
AJAY KUMAR RAJAWAT ◽  
PRAVEEN KUMAR

An attempt has been made to study the Physico-chemical condition of water of Yamuna River at Gokul Barrage, Mathura, (UP). The time period of study was July 2015 to June 2016. Three water samples were selected from different sites in each month for study. The parameters studied were Temperature, Turbidity, pH, DO, BOD, COD, Total Dissolved Solids and Suspended Solids. Almost all the parameters were found above the tolerance limit.


2021 ◽  
Vol 36 (1) ◽  
Author(s):  
Ai Yuningsih Yuningsih

The Lesser Sunda Islands extend from Bali to Timor and consist of two geologically distinct parts formed by a subduction system of oceanic crust along the Java-Timor Trench. The northern part which includes Bali, Lombok, Sumbawa, Flores, Wetar, Pantar and Alor, is volcanic in origin; whilst the southern part is non-volcanic, encompassing the islands of Sumba, Timor and Rote. The straits along the Lesser Sunda Islands are formed as a result of very complex geological processes and tectonics in this area. These straits are the most important cross-sections in the southern part of the Indonesian Throughflow (ITF), functioning as outlets for the mass flows of seawater from the Pacific Ocean to the Indian Ocean through the Flores and the Savu Seas. In these straits, relatively high current speeds are occurred, not only caused by the ITF but also due to its geometry, the influence of tidal flow, and monsoonal currents.Site study and ocean current measurement were conducted by using an echosounder, a pair of Acoustic Doppler Current Profilers (ADCP), and other supporting equipment. In general, the average of most ocean current speeds is less than 1.5 m/s with a duration flow of 8 -12 hours a day, and the maximum speed reaches up to 3 m/s. The tidal types in almost all the straits are mixed semidiurnal tides, in which two high waters and two low waters occur twice a day, with the high and low tides differ in height.The Lesser Sunda Straits were selected as the potential sites for ocean current power plant because their current speeds are relatively high and their characteristics are more predictable compared with other straits from other regions. Based on the results of bathymetry survey and current characteristics from the deployed ADCP at a fixed (stationary) location on the seabed, the best location for the current power turbines is at the depth of 15-30 m where the seabed gently sloping.


2021 ◽  
Author(s):  
◽  
Krunoslav Puškar

This thesis deals with the analysis and description of the historical and contemporary anthroponymy of the Kalnik area of the Prigorje region on the basis of both archival and field research carried out throughout a longer period of time. Since there has not been any extensive onomastic reasearch in the very area to date, our goal was to determine the influence of linguistic and extralinguistic changes in the reaserched onomastic categories. The introduction of this thesis provides the geographical, sociohistorical, demographical and linguistic context of the researched area, whereas the subsequent chapters provide a list and analysis of confirmed first names, personal and family nicknames, as well as family names of the reaserched area. First names were researched during nine time periods with a duration of five years, beginning from 1802 and ending in 2014. Because of a wide researched area, we limited our research on the anthroponymic repertoire of the city of Križevci, in which 3020 first names (1579 male and 1441 female names) were confirmed. In the 19th century, during five analysed time periods, 1519 first names were confirmed, out of which 814 male and 705 female names, which were mostly simple based on their structure (91.64%). Concerning the provenance of the first names, we established that almost all names were either Christian names or translated Christian names and that national names occur very rarely and sporadically, only in the second half of the 19th century. By comparison, in the 20th and 21st century, during the last four time periods, 1501 first names have been confirmed, out of which 765 were male and 736 female names. Concerning their structure, they turned out to be mostly compound first names in the 1946- 1950 time period (55.69%), whereas in the 2010-2014 time period they turned out to be predominantly single (97.02%). Concerning their provenance, in the 1946-1950 time period 48.39% of male and 57.58% of female national names were confirmed, whereas in the last time period male national names amount to 4.05%, and female national names to only 1.27%. Personal nicknames are a special anthroponymic category which has not been researched in the Kalnik area. Having limited our field research on 13 places throughout the area, we confirmed 288 real personal nicknames, 245 male and 43 female nicknames, of mostly simple structure (95.14%), which are still mostly used in oral and informal communication. The motivation behind the nicknames has faithfully shown us the extralinguistic reality of the researched area. The most frequent motivational group of nicknames is the one of unknown motivation (23.96%), while the other confirmed groups are nicknames motivated by a first name (12,15%), a physical characteristic of the owner (12.15%), another characteristic of the owner (11,81%), a specific word used by the owner (8.33%), an animal (6.94%), a family name (6.60%), an occupation (6.25%), an ethnonym or toponym (4.51%), a family or social role (2.78%), a professional designation (1.38%), food (1.04%), a name for a plant (1.04%), a subject (0.69%), and another nickname (0.35%). The high frequency of nicknames of unknown motivation shows us the importance of future research of this anthroponymic category because, due to the passage of time, it is difficult to determine the real motivation of every nickname. We came to the same conclusion during our research of family nicknames, another specific anthroponymic category, still quite present in the Kalnik area. Having limited our field research on 12 places throughout the wide researched area, we managed to confirm 173 real family nicknames, whose designated motivational groups provided us with important sociolinguistic pieces of information. Concerning their structure, the majority of family nicknames turned out to be simple (N = 129), whereas concerning their motivation, the majority of family nicknames were of unknown motivation (N = 33). Other motivational groups were the following: a first name (N = 27), an occupation (N = 27), a family name (N = 25), a personal nickname (N = 22), a certain characteristic (N = 13), an ethnonym (N = 10), a toponym (N = 6), a certain subject (N = 6), and an animal (N = 4). All these mentioned different anthroponymic categories (first names, personal and family nicknames) can be confirmed profusely in the last anthroponymic category researched and analysed in this thesis – family names. Having employed the criterion of their minimum continuity of 100 years in the researched area, we have managed to confirm 1360 family names with centuries old continuity, since the 14th century to this very day. With this criterion we also managed to reduce a significant number of over 3000 family names with mostly no continuity, as well as to confirm those last names which had left their trace in the researched area. Of course, not all family names confirmed by this criterion are necessarily connected to the researched area, but are only detected in it. Out of 1360 confirmed family names, we succeeded in determining 189 family names which occur exclusively or mostly in the researched area, 100 family names which do not occur in contemporary anthroponymy of the area, and 97 family names which could also become extinguished in near future. Concerning their structure, the majority of all family names occur without a suffix (N = 681). All the confirmed family names were analysed according to their structure and motivation and listed in our Lexicon of family names at the end of this very thesis.


Author(s):  
Jeffrey D. Cochran ◽  
Trace P. Silfies ◽  
Jonathan D. Dobis

The manufacture of low density polyethylene (LDPE) by radical polymerization regularly subjects components to extreme pressures exceeding 20 ksi and, possibly, to runaway decomposition reactions with temperatures exceeding 1500 °F and pressures above 30 ksi. Components subject to such extreme conditions are often autofrettaged to induce a beneficial residual stress distribution that retards crack growth and extends fatigue life. Three samples of autofrettaged tubes extracted from these components are examined here. Only one of these samples is known to have been exposed to multiple decompositions while in service. Measurements of the remaining residual stress were taken for each of these tube samples, and a number of other metallurgical tests were performed. The results show that the tube experiencing decompositions lost almost all of the beneficial residual stress induced by autofrettage and actually has a large, detrimental tensile stress at the inner surface. Corresponding to this is a band of embrittled material with a significantly altered microstructure that was most likely caused by thermal excursions. The tubes that experienced no decompositions showed no such alterations, and their residual stress distributions were relatively intact. An FFS assessment of crack-like flaws was performed on these tubes in accordance with API 579-1/ASME FFS-1 in order to determine the effect of this loss of residual stress on remaining life and quantify this loss in terms of a damage parameter.


1999 ◽  
Vol 36 (2) ◽  
pp. 272-290 ◽  
Author(s):  
Amer Ali Al-Rawas ◽  
A McGown

The fundamental factors controlling the expansive nature of Omani soils are their characteristics with respect to geology, mineralogy, engineering, and microstructure. The first three factors have been extensively studied, however, the fourth has not yet been fully investigated and no work has been published on this aspect. Therefore, this paper deals with the microstructure characteristics of these soils. The scanning electron microscope was employed in this investigation. Three samples selected from different sites where expansive soils problems were known (Al-Khod, Al-Murtafa'a, and Duqm) were investigated. Two specimens from each sample, representing the vertical and horizontal planes, were tested. In addition, two samples that were subjected to swelling were tested to investigate the microfabric changes caused by swelling. The fabric of the Omani expansive soils studied generally consists of dense clay matrices, although clay-granular matrices are occasionally observed. In addition, no connectors have been observed and only few aggregations have been seen. Pore spaces are mainly of the intra-assemblage and intra-elemental types. Significant microfabric changes were induced by swelling.Key words: microstructure, microfabric, SEM, expansive soils, Oman, clay minerals.


2017 ◽  
Vol 5 (3) ◽  
pp. SK65-SK81 ◽  
Author(s):  
Sigurd Kjoberg ◽  
Tobias Schmiedel ◽  
Sverre Planke ◽  
Henrik H. Svensen ◽  
John M. Millett ◽  
...  

The mid-Norwegian margin is regarded as an example of a volcanic-rifted margin formed prior to and during the Paleogene breakup of the northeast Atlantic. The area is characterized by the presence of voluminous basaltic complexes such as extrusive lava and lava delta sequences, intrusive sills and dikes, and hydrothermal vent complexes. We have developed a detailed 3D seismic analysis of fluid- and gas-induced hydrothermal vent complexes in a [Formula: see text] area in the Møre Basin, offshore Norway. We find that formation of hydrothermal vent complexes is accommodated by deformation of the host rock when sills are emplaced. Fluids are generated by metamorphic reactions and pore-fluid expansion around sills and are focused around sill tips due to buoyancy. Hydrothermal vent complexes are associated with doming of the overlying strata, leading to the formation of draping mounds above the vent contemporary surface. The morphological characteristics of the upper part and the underlying feeder structure (conduit zone) are imaged and studied in 3D seismic data. Well data indicate that the complexes formed during the early Eocene, linking their formation to the time of the Paleocene-Eocene thermal maximum at c. 56 Ma. The well data further suggest that the hydrothermal vent complexes were active for a considerable time period, corresponding to a c. 100 m thick transition zone unit with primary Apectodinium augustum and redeposited very mature Cretaceous and Jurassic palynomorphs. The newly derived understanding of age, structure, and formation of hydrothermal vent complexes in the Møre Basin contributes to the general understanding of the igneous plumbing system in volcanic basins and their implications for the paleoclimate and petroleum systems.


2020 ◽  
Author(s):  
Milica Radaković ◽  
Bojan Gavrilović ◽  
Luka Bosnić ◽  
Milivoj Gavrilov ◽  
Pal Sümegi ◽  
...  

<p>We present our preliminary findings from the survey of malacofauna of the Titel loess plateau – Mošorin site (Serbia), conducted during 2018/2019. Titel loess plateau is situated near the confluence of Tisa and Danube rivers, in the southern central part of the Vojvodina province, the region known for having valuable continental climate record for the past million years. The study aims to gather palaeoenvironmental data and discern patterns of environmental changes during the Pleistocene in the loess domain. Previous surveys were done at the loess sites in Batajnica, Zemun, Crvenka and Irig. The exposed part of the Mošorin loess-paleosol section is 30 m high and covers the last three glacial periods. It is the first time we carried out a malacological analysis on the L3 segment of the profile. A total of 26 samples were collected from 5.2 m long cleaned profile section (ending of S3 to the beginning of S2). Nine species of snails were present in this horizon, including <em>Chondrula tridens</em>, <em>Granaria frumentum</em>, <em>Helicopsis striata</em>, <em>Pupilla muscorum</em>, <em>Pupilla triplicata</em>, <em>Punctum pygmaeum</em>, <em>Succinella oblonga</em>, <em>Vallonia costata</em>, <em>Vitrina pellucida,</em> and certain as-yet-unidentified slug taxa (Limacidae, Agriolimacidae, Milacidae). Greatest diversity and abundance was found near the S3 paleosol. Samples with no snail shells are continuous, and they are situated in the middle and upper part of the studied profile section. The first three samples that are closest to S3 include 65% of all snails shells found in the profile. The number of snail taxa and their abundance gradually increases again toward the S2 paleosol. Based on ecological preferences of discovered species (mostly thermophilous and xerophilous) we deduced that the environment during the L3 time period was an opened grassland, while the climate was mild and mostly dry.</p>


2017 ◽  
Vol 2 (2) ◽  
Author(s):  
Cândida Ferreira

<span class="fontstyle0">This paper analyses the co-integration relationship between globalisation and economic<br />growth of 27 more or less developed countries across almost all Continents for the time period<br />1970–2013. Globalisation is </span><span class="fontstyle2">proxied </span><span class="fontstyle0">by the overall globalisation index and the sub-indices<br />representing economic globalisation, social globalisation and political globalisation, all<br />provided by the Swiss Economic Institute. Economic growth is measured through the natural<br />logarithm of the real Gross Domestic Product, sourced from the World Development<br />Indicators which are provided by the World Bank. Co-integration is tested with quantile cointegration regressions. The results obtained clearly confirm the existence of non-linear cointegration relationships between the considered globalisation indices and the real economic<br />growth.</span>


2021 ◽  
Vol 7 (12) ◽  
pp. 2130-2149
Author(s):  
Shashi Shankar Ojha ◽  
Vivekanand Singh ◽  
Thendiyath Roshni

Drought assessment is crucial for effective water resources management in a river basin. Drought frequency has increased worldwide in recent years due to global warming. In this paper, an attempt is made to assess the meteorological drought in the Punpun river basin, India using two globally accepted drought indices namely, Standardized Precipitation Index (SPI) and Standardized Precipitation Evapotranspiration Index (SPEI). The SPI and SPEI at 1-, 3-, 6-, 9-, and 12-month timescale were obtained to analyze the temporal variability of different drought levels. Correlation analysis of available observed data and gridded data has been carried out and the correlation coefficient was found to be 0.956. Hence gridded rainfall data from the year 1991 to 2020 is used for further analysis. Potential evapotranspiration (PET) used in the calculation of SPEI was computed by the Thornthwaite method. Water deficit was observed throughout as there is a decrease in rainfall and an increase in PET during the selected period. The results show that the period 2004 to 2006 and 2009 to 2010 years are observed as drought periods by both indices for almost all timescale. The intensity and duration of drought have increased after 2004. A negative trend of both the indices have been observed in all seasons on all timescale, which clearly shows a transition from near normal to moderately dry during the selected time period. The highest correlation between both the indices is for the 12-month scale with R² value 0.92 and the RMSE value 0.28. The main outcome of this study is that both SPI and SPEI show a strong correlation on same time scales adopted in this study. The dependency of SPEI on temperature is also observed in this study. Doi: 10.28991/cej-2021-03091783 Full Text: PDF


2006 ◽  
Vol 24 (18_suppl) ◽  
pp. 10568-10568
Author(s):  
A. Larke ◽  
A. O’Doherty ◽  
C. Quinn

10568 Background: Breast cancer screening programmes reduce mortality but result in increased numbers of breast biopsies. Stereotactic and ultrasound-guided core needle biopsy yield similar results to each other and to open biopsy. Study: Analysis of prospectively-acquired data relating to 174,338 screening mammograms performed in BreastCheck between Jan 2001 to Oct 2004. Relative use of ultrasound and stereotactic guidance for core needle biopsy is ascertained, and malignancy yields analysed. Results: In this time period, 174,338 screening mammograms discovered a total of 2782 lesions requiring further assessment. Of 2760 complete records, 1066 were BiRads R3–5 (39%) and 1033 of these (97%) had CNB. Guidance was provided exclusively by ultrasound in 737 (71%), and by stereotaxis in 270 (26%) of cases. There were no differences in malignancy yield of ultrasound versus sterotactically-guided CNB of R4 and R5 lesions (approximately 50% and 90% respectively). The malignancy yield in R3 lesions was significantly higher when performed with stereotactic guidance (12%) than when performed with ultrasound-guidance (5%) and both were significantly higher than R3 biopsy malignancy yields reported in the literature. Conclusion: Almost all BIRADS 3, 4 and 5 lesions are biopsied. The relatively high malignancy yield in R3 biopsies, particularly those with calcification, supports current practice. No significant financial relationships to disclose.


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