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132. Structural framework of the Zelten Platform, South Sirte Basin, Libya using potential fields modelling
- Creator:
- Eshanibli, Abdelhakim, Khalil, Amin, Younis, Abdellatif, and Ghanoush, Hussin
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- geodynamika, geodynamics, Libye, Libya, magnetic anomaly, gravity anomaly, geologic structure, Zelten platform, Sirt basin, 7, and 551
- Language:
- English
- Description:
- Integration between magnetic and gravity data at the Zelten platform, the southeast part of Sirt Basin Libya. Zelten Platform is first discovered oil field in Libya. It shows numerous geological structures of different tectonic events. The methods adopted can assist in locating the hidden subsurface structures. The platform is characterized by the NW-SE trending rift that belongs to the Early Cretaceous age (during the collapse of Sirt Arch). The study aimed to define the structural geology that assisted in the development of future exploration in this area. The analyses utilized several filtering and transformation algorithms to help in structural modeling. For instance, the total horizontal gradient and tilt angle derivative were applied for the edge detection of the tectonic boundaries. The results show NW-SE and NNW-SSE patterns that represents faults that controlled the positions of the troughs and platforms at the Sirt basin. On the other hand, Euler deconvolution and 2D forward modeling were utilized to determine the depth of the basement. The Integrated models deduced revealed that the main faults trends are NW-SE which refer to the rift phases and crustal extension period that occurred during the Mesozoic time (early cretaceous). Also, the basement depth ranges from 6.5 km to 8 km according to the structures that affected the study area., Abdelhakim Eshanibli, Amin Khalil, Abdellatif Younis and Hussin Ghanoush., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
133. Studies on the effect of the proppant embedment phenomenon on the effective packed fracture in shale rock
- Creator:
- Maslowski, Mateusz, Kasza, Piotr, and Wilk, Klaudia
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- geodynamika, geomechanika, geofyzika, geologie, geodynamics, geomechanics, geophysics, geology, břidlice, fracture width, embedment, hydraulic fracturing, shale, proppant, effective packed fracture, 7, and 551
- Language:
- English
- Description:
- This paper presents the subject related to the technology of creating fractures into a rock, as well as the subject related to the effect of the proppant embedment phenomenon on the effective packed fracture in a reservoir rock. This phenomenon occurs after the performed hydraulic fracturing treatment of hydrocarbon reservoirs, during closing of the rock mass. A key part of this experiment was to investigate the depth of proppant grains penetration into the fracture wall (shale rock) and size of damage to the fracture wall surface. The embedment phenomena effects on decrease in the width fracture packed with proppant. The tests were performed for shale rock initially soaked with fracturing fluid, lightweight ceramic proppant grains with a grain size of 0.600÷0.300 mm (medium diameter of proppant grains of 0.450 mm), low surface concentration of proppant of 2.44 kg/m2. Time of exposure of proppant grains to compressive stress of a value 48.3 MPa for 6 hours at 70 oC. Test results indicate that the developed testing methodology may be used for corrected evaluation of the fracturing fluid as well as proppant in hydraulic fracturing treatment of unconventional reservoirs, especially shale rocks. and Maslowski Mateusz, Kasza Piotr, Wilk Klaudia.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
134. Study on the law mining stress evolution and fault activation under the influence of normal fault
- Creator:
- Wu, Quan-sen, Jiang, Li-shuai, and Wu, Quan-lin
- Format:
- print, bez média, and svazek
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Geologie. Meteorologie. Klimatologie, horniny, hornictví, rocks, mining, normal fault, mining stress distribution, fault activation, energy evolution, rock burst hazard, 7, and 551
- Language:
- English
- Description:
- Using the FLAC3D numerical simulation method, the characteristics of mining stress evolution, fault activation patterns, and fault energy evolution characteristics are simulated and analyzed in the process of the footwall and hanging wall working face heading to a normal fault. The study shows that the fault cut off the mining stress propagation of overlying strata, and the stress blocking effect due to the fault is evident. When working faces head towards a fault, the abutment pressure and the vertical stress of the surrounding rock increase first and subsequently decrease. The abutment pressure of the coal wall and fault is highest when the distances to the fault are 40 m and 30 m for the footwall and hanging wall working faces, respectively. Moreover, the hanging wall mining stress is higher than the footwall mining stress. Fault activation in high-located strata precedes that in low-located strata when working faces head towards the normal fault. Energy is gradually accumulated before unstable fault events take place because of mining, and fault instability quickly releases a lot of energy. The mining stress concentration and fault activation due to faults easily result in rock bursts and mine seismicity, Wu Quan-sen, Jiang Li-shuai and Wu Quan-lin., and Obsahuje bibliografické odkazy
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
135. Sv. Jan pod Skalou (Sv. Ivan) a jeho okolí
- Creator:
- Jan Evangelista Korejs and Pavel Körber
- Publisher:
- Pavel Körber
- Format:
- print and 53 stran : ilustrace, mapka ; 20 cm
- Type:
- model:monograph and TEXT
- Subject:
- Geografie Česka a Slovenska, reálie, cestování, Svatý Jan pod Skalou (klášter), Svatý Jan pod Skalou (Česko), Praha (okolí), Český kras (Česko), Čechy střední (Česko), poč. 20. stol., historické průvodce, historické místopisy, 7, and 913(437)
- Language:
- Czech
- Description:
- Průvodce ediční řady turistických průvodců vydávaných před 1. světovou válkou Pavlem Körbrem popisuje výletní a bývalé lázeňské místo v Českém krasu a jeho blízké okolí., napsal Jan Ev. Koreis ; k tisku upravil, doplnil a illustracemi opatřil Pavel Körber, Obsahuje dobové reklamy a inzeráty, Průvodce: Česká republika. Praha., and Sankt Johann unter dem Felsen (Česko). Středočeský kraj (Česko). Topografie (sbírkový fond). Vlastivěda. Vzácné a historické tisky MKP (sbírkový fond). Vzácné tisky 20. stol. (sbírkový fond). Text
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
136. Světem automobilem: z Pekingu do Paříže v 60 dnech
- Creator:
- Luigi Barzini and František Pover
- Publisher:
- Jos. R. Vilímek
- Format:
- print, text, regular print, and xx, 439 s., [13] l. obr. příl. : il., mapy, portréty ; 24 cm
- Type:
- model:monograph and TEXT
- Subject:
- Geografie jako věda. Výzkum. Cestování, cestování, Evropa, Asie, automobilismus, 910.4, 656.13, (4), (5), (0:82-992), 7, and 91
- Language:
- Czech and Italian
- Description:
- napsal Luigi Barzini ; autor. překlad Fr. Povera and Přeloženo z italštiny
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
137. Švýcarské scenerie
- Creator:
- Božena Viková-Kunětická and Josef Svatopluk Machar
- Publisher:
- F. Šimáček
- Format:
- print, text, regular print, and 118, viii s. ; 17 cm
- Type:
- model:monograph and TEXT
- Subject:
- Geografie Evropy, reálie, cestování, cesty a pobyt, Švýcarsko, 910.4, 913(494), (0:82-992), 7, and 913(4)
- Language:
- Czech
- Description:
- Božena Viková Kunětická and "Studie Paní Božena Viková-Kunětická od J.S. Machara vyšla původně německy ve vídeňské revui "Documente der Frauen", český originál pak v "Ženském obzoru" v Praze"--Údaj převzat z SKC ČR
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
138. Temperature and pressure effect on permeability of Chinese sandstone: a review
- Creator:
- Ge, Zhenlong, Sun, Qiang, and Li, Wenping
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- vysoké teploty, propustnost materiálů, high temperatures, permeability, confining pressure, threshold temperature, 7, and 551
- Language:
- English
- Description:
- Permeability plays an important role in the field of geotechnical engineering. Under high temperature and high pressure condition, the physical-chemical and structure properties (such as decomposition, oxidation, dehydration, evaporation, phase transition etc.) of rock have obviously changing, which are significant affected the rock permeability. In order to analyze the influence of temperature and confining pressure on the permeability of rock (sandstones, siltstones and conglomerates) data for permeability was obtained from the literature. The results indicate that temperature and confining pressure have great influence on the permeability of rock, especially for sandstone. There is a threshold temperature and when the heating temperature is lower than the threshold temperature, the permeability of sandstone gradually increases with an increase in temperature. When the heating temperature is higher than 300 ºC (especially 400 ºC), the permeability rapidly increases. The permeability of sandstone decreases gradually with the confining pressure increases. This study of the relationship between rock permeability and temperature and confining pressure lays a foundation for investigations of multi-disciplinary issues regarding high temperatures and high pressures and it can be used for the study of petroleum storage and safe nuclear waste disposal., Zhenlong Ge, Qiang Sun and Wenping Li., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
139. The causes of mining induced ground steps occurence: case study from Upper Silesia in Poland
- Creator:
- Strzałkowski, Piotr and Ścigałan, Roman
- Format:
- print, bez média, and svazek
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Geologie. Meteorologie. Klimatologie, hornictví, mining, hornoslezská pánev (Česko a Polsko), post-mining discontinuous deformations, ground steps, predictions of post-mining deformations, 7, and 551
- Language:
- English
- Description:
- The case study of a ground steps creation due to underground mining in Upper Silesia Basin, where for many years was conducted intensive hard coal extraction has been presented in this paper. This type of linear discontinuous deformations is considered as an important threat to the surface building constructions and elements of underground technical infrastructure. This threat is even more important, that presently still we do not have methods for predictions of such phenomena, and protection of building constructions against such damages is difficult, if not impossible. On the basis of the analyzes results shown in the paper, the following factors were pointed, that favor the formation of mining-induced ground steps: the presence of fault outcrops in the vicinity of extraction fields, multiple extraction in several coal seams led to the same border and large values of tensile horizontal strain., Piotr Strzałkowski and Roman Ścigała., and Obsahuje bibliografické odkazy
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
140. The impact of tropospheric mapping function on PPP determination for one-month period
- Creator:
- Nistor, Sorin, Suba, Norbert-Szabolcs, and Buda, Aurelian-Stelian
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- geodynamika, geodynamics, PPP, mapping function, postfit residuals, standard deviation, GNSS, repeatability, 7, and 551
- Language:
- English
- Description:
- When using the PPP method, it is recommended to take into account the tropospheric influences for obtaining reliable estimates. Global Navigation Satellite System (GNSS) observations taken at low elevation suffer more strongly from atmospheric, antenna phase center variation and multipath effects, hence the observations are noisier than those at higher elevation angle, but they are essential to decorrelate the estimated station height and tropospheric zenith delay (ZTD). To relate the ZTD in the direction of an observation, the so-called mapping function (MF) are used. In this article the influence of different mapping function was studieds such as: Niell mapping function (NMF), Global Mapping Function (GMF) in conjunction with the Global Pressure and Temperature 2-GPT2, Vienna Mapping Function 1 and no mapping function. The MF were used at different elevation cutoff angles - 50 , 70, 100 and 150. The impact was analyzed: a) on the postfit residuals of the ionospheric free combination for phase (LC) and for pseudorange (PC), b) daily variability for North, East and Up component; c) evaluation of coordinates repeatability and how they are affected by the changes of the cutoff elevation angle and mapping function. The analyzed data was taken from 4 EUREF stations for a period of one month - October 2015. By using the VMF1 mapping function, the lowest value was obtained for the postfit residuals of the LC combination for all the stations. The difference in daily variation between each individual solution for the horizontal component is at the level of ~0.3 ÷ 0.5 mm, with smaller effect on the East component compared to North, whereas the Up component is at the level of ~1.0 ÷ 1.5 mm. The standard deviation (SD) is used as a measure of station position repeatability and the results suggested that for high precision determination a cutoff elevation angle of 100 should be used., Sorin Nistor, Norbert-Szabolcs Suba and Aurelian-Stelian Buda., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public