scholarly journals Submarine Stratovolcano Peperite Syn-Formational Alteration - A Case Study of the Oligocene Smrekovec Volcanic Complex, Slovenia

2021 ◽  
Author(s):  
Polona Kralj
Keyword(s):  
Temperature Stability ◽  
Volcanic Complex ◽  
Pore Waters ◽  
Authigenic Minerals ◽  
Fine Grained ◽  
Temperature Regimes ◽  
Porosity And Permeability ◽  
Higher Temperature ◽  
Favourable Environment

The Oligocene Smrekovec Volcanic Complex is a remnant of a submarine composite stratovolcano with a complex succession of lavas, autoclastic, pyroclastic, syn-eruptive resedimented volcaniclastic and siliciclastic deposits was a favourable environment for the development of peperites. Despite very complex alteration related to the stratovolcano-hosted hydrothermal system with a deep igneous source, locally elevated geothermal gradients and superimposed hydrothermal/geothermal regimes controlled by the emplacement of a shallow intrusive body, authigenic minerals in peperites - particularly pumpellyite and actinolite - show higher temperature stability ranges than those in the underlying and overlying volcanic deposits irrespectively of their lithofacies, porosity and permeability. The formation of authigenic minerals in peperites, such as laumontite, pumpellyite, epidote, prehnite or actinolite, was apparently controlled by ephemeral and localised high-temperature regimes originating from the parent lava flow. Heated pore waters in the host sediment that could have undergone local mixing with deuteric fluids circulated in peperites until thermal gradients persisted, and were the cause of alteration of juvenile clasts and the mingling sediment. The development of pumpellyite required a suitable precursor - fine-grained volcanic ash.

Overpressure Identification Using The Eaton Method on The Gumai Formation of Geragai Graben, Jambi Sub Basin

2020 ◽  
Author(s):  
A. O. Marnila
Keyword(s):  
Pressure Data ◽  
Stratigraphic Sequence ◽  
Fine Grained ◽  
Marine Sedimentation ◽  
Plot Analysis ◽  
Significant Reversal ◽  
Porosity And Permeability ◽  
Upper Level ◽  
Type Data ◽  
Fine Grained Sand

Geragai graben is located in the South Sumatera Basin. It was formed by mega sequence tectonic process with various stratigraphic sequence from land and marine sedimentation. One of the overpressure indication zones in the Geragai graben is in the Gumai Formation, where the sedimentation is dominated by fine grained sand and shale with low porosity and permeability. The aim of the study is to localize the overpressure zone and to analyze the overpressure mechanism on the Gumai Formation. The Eaton method was used to determine pore pressure value using wireline log data, pressure data (RFT/FIT), and well report. The significant reversal of sonic and porosity log is indicating an overpressure presence. The cross-plot analysis of velocity vs density and fluid type data from well reports were used to analyze the causes of overpressure in the Gumai Formation. The overpressure in Gumai Formation of Geragai graben is divided into two zones, they are in the upper level and lower level of the Gumai Formation. Low overpressure have occurred in the Upper Gumai Formation and mild overpressure on the Lower Gumai Formation. Based on the analyzed data, it could be predicted, that the overpressure mechanism in the Upper Gumai Formation might have been caused by a hydrocarbon buoyancy, whereas in the Lower Gumai Formation, might have been caused by disequilibrium compaction as a result of massive shale sequence.

scholarly journals Potential Impacts of Future Climate Change Scenarios on Ground Subsidence

Water ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 219 ◽  
Author(s):  
Antonio-Juan Collados-Lara ◽  
David Pulido-Velazquez ◽  
Rosa María Mateos ◽  
Pablo Ezquerro
Keyword(s):  
Climate Change ◽  
Land Subsidence ◽  
Ground Subsidence ◽  
Lower Percentage ◽  
Future Climate Change ◽  
Climate Change Scenarios ◽  
Fine Grained ◽  
Fine Grained Material ◽  
The Impact

In this work, we developed a new method to assess the impact of climate change (CC) scenarios on land subsidence related to groundwater level depletion in detrital aquifers. The main goal of this work was to propose a parsimonious approach that could be applied for any case study. We also evaluated the methodology in a case study, the Vega de Granada aquifer (southern Spain). Historical subsidence rates were estimated using remote sensing techniques (differential interferometric synthetic aperture radar, DInSAR). Local CC scenarios were generated by applying a bias correction approach. An equifeasible ensemble of the generated projections from different climatic models was also proposed. A simple water balance approach was applied to assess CC impacts on lumped global drawdowns due to future potential rainfall recharge and pumping. CC impacts were propagated to drawdowns within piezometers by applying the global delta change observed with the lumped assessment. Regression models were employed to estimate the impacts of these drawdowns in terms of land subsidence, as well as to analyze the influence of the fine-grained material in the aquifer. The results showed that a more linear behavior was observed for the cases with lower percentage of fine-grained material. The mean increase of the maximum subsidence rates in the considered wells for the future horizon (2016–2045) and the Representative Concentration Pathway (RCP) scenario 8.5 was 54%. The main advantage of the proposed method is its applicability in cases with limited information. It is also appropriate for the study of wide areas to identify potential hot spots where more exhaustive analyses should be performed. The method will allow sustainable adaptation strategies in vulnerable areas during drought-critical periods to be assessed.

SonicFace

2021 ◽  
Vol 5 (4) ◽  
pp. 1-33
Author(s):  
Yang Gao ◽  
Yincheng Jin ◽  
Seokmin Choi ◽  
Jiyang Li ◽  
Junjie Pan ◽  
...  
Keyword(s):  
Facial Expressions ◽  
Microphone Array ◽  
Wearable Sensors ◽  
Real Life ◽  
Privacy Concerns ◽  
Fine Grained ◽  
Recognition Of Facial Expressions ◽  
Ubiquitous Sensing ◽  
Contact Free

Accurate recognition of facial expressions and emotional gestures is promising to understand the audience's feedback and engagement on the entertainment content. Existing methods are primarily based on various cameras or wearable sensors, which either raise privacy concerns or demand extra devices. To this aim, we propose a novel ubiquitous sensing system based on the commodity microphone array --- SonicFace, which provides an accessible, unobtrusive, contact-free, and privacy-preserving solution to monitor the user's emotional expressions continuously without playing hearable sound. SonicFace utilizes a pair of speaker and microphone array to recognize various fine-grained facial expressions and emotional hand gestures by emitted ultrasound and received echoes. Based on a set of experimental evaluations, the accuracy of recognizing 6 common facial expressions and 4 emotional gestures can reach around 80%. Besides, the extensive system evaluations with distinct configurations and an extended real-life case study have demonstrated the robustness and generalizability of the proposed SonicFace system.

The impact of business networks on foreign subsidiaries development

IMP Journal ◽  
2018 ◽  
Vol 12 (3) ◽  
pp. 427-443
Author(s):  
Enrico Baraldi ◽  
Francesco Ciabuschi ◽  
Olof Lindahl ◽  
Andrea Perna ◽  
Gian Luca Gregori
Keyword(s):  
Single Case ◽  
Foreign Market ◽  
Business Networks ◽  
International Expansion ◽  
Content Type ◽  
Fine Grained ◽  
Automatic Control Systems ◽  
Industrial Networks ◽  
The Impact

Purpose The purpose of this paper is to explore two specific areas pertaining to industrial networks and international business (IB). First, the authors look at how business relationships influence the internationalization in time, from the establishment of the first subsidiary in a foreign market to the following ones, and in space, that is, across different markets. Second, the authors investigate how an increasing external network dependence of subsidiaries in their internationalization may cause a detachment of a subsidiary from the mother company as its knowledge becomes insufficient to guide a subsidiary’s internationalization. Design/methodology/approach This paper utilizes an exploratory, longitudinal, single-case study of Loccioni – a manufacturer of measuring and automatic control systems for industrial customers – to illustrate the specific dynamics of the influences of industrial networks on the internationalization of subsidiaries. Findings The case study helps to elucidate the roles, entailing also free will and own initiative, of small suppliers’ subsidiaries which operate inside several global factories, and how “surfing” on many different global factories, by means of several local subsidiaries, actually supports these suppliers’ own international developments. This notion adds to our understanding of the global factory phenomenon a supplier focus that stresses how the role of suppliers is not merely that of being passive recipients of activities and directions from a focal orchestrating firm, but can also be that of initiative-takers themselves. Originality/value The paper contributes to the IMP tradition by providing a multi-layered and geographically more fine-grained view of the network embedding companies that operate on internationalized markets. This paper thereby sheds light on a less investigated area of research within the IMP tradition: the link between internationalization in different countries and the interconnectedness between the industrial networks spanning these countries. At the same time, this paper contributes to IB theories by showing how a late-internationalizing SME can enter highly international markets by “plugging into” several established “Global Factories” as a way to exploit further opportunities for international expansion.

Recent Advances in Mechanical Properties Evaluation of Solid Propellants

1964 ◽  
Vol 37 (2) ◽  
pp. 542-556 ◽  
Author(s):  
James H. Wiegand
Keyword(s):  
Mechanical Properties ◽  
Stress Analysis ◽  
Elastic Analysis ◽  
Solid Propellants ◽  
Metallic Structures ◽  
Temperature Regimes ◽  
Nonlinear Stress ◽  
Analytical Correlation ◽  
Wide Variability ◽  
Higher Temperature

Abstract Methods of mechanical properties measurement have become more sophisticated as the necessities of nonlinear stress analysis have been appreciated. The linear cases, typical of low temperature failure, have been successfully handled by elastic analysis, but the nonlinear complexities of the higher temperature regimes require analytical correlation of real properties and analytical methods of using such correlations. The wide variability of mechanical properties observed in solid propellants requires that predictions of failure be based on estimates of upper and lower expected limits rather than viewing failure as a point value, as is often done in stress analysis of metallic structures.

scholarly journals Reservoir quality and its controlling diagenetic factors in the Bentiu Formation, Northeastern Muglad Basin, Sudan

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yousif M. Makeen ◽  
Xuanlong Shan ◽  
Mutari Lawal ◽  
Habeeb A. Ayinla ◽  
Siyuan Su ◽  
...  
Keyword(s):  
Clay Content ◽  
Petroleum Exploration ◽  
Reservoir Quality ◽  
Burial Depth ◽  
Petroleum Reservoir ◽  
Fine Grained ◽  
Porosity And Permeability ◽  
Negative Role ◽  
Crevasse Splay ◽  
Channel Deposits

AbstractThe Abu Gabra and Bentiu formations are widely distributed within the interior Muglad Basin. Recently, much attention has been paid to study, evaluate and characterize the Abu Gabra Formation as a proven reservoir in Muglad Basin. However, few studies have been documented on the Bentiu Formation which is the main oil/gas reservoir within the basin. Therefore, 33 core samples of the Great Moga and Keyi oilfields (NE Muglad Basin) were selected to characterize the Bentiu Formation reservoir using sedimentological and petrophysical analyses. The aim of the study is to de-risk exploration activities and improve success rate. Compositional and textural analyses revealed two main facies groups: coarse to-medium grained sandstone (braided channel deposits) and fine grained sandstone (floodplain and crevasse splay channel deposits). The coarse to-medium grained sandstone has porosity and permeability values within the range of 19.6% to 32.0% and 1825.6 mD to 8358.0 mD respectively. On the other hand, the fine grained clay-rich facies displays poor reservoir quality as indicated by porosity and permeability ranging from 1.0 to 6.0% and 2.5 to 10.0 mD respectively. A number of varied processes were identified controlling the reservoir quality of the studies samples. Porosity and permeability were enhanced by the dissolution of feldspars and micas, while presence of detrital clays, kaolinite precipitation, iron oxides precipitation, siderite, quartz overgrowths and pyrite cement played negative role on the reservoir quality. Intensity of the observed quartz overgrowth increases with burial depth. At great depths, a variability in grain contact types are recorded suggesting conditions of moderate to-high compactions. Furthermore, scanning electron microscopy revealed presence of micropores which have the tendency of affecting the fluid flow properties in the Bentiu Formation sandstone. These evidences indicate that the Bentiu Formation petroleum reservoir quality is primarily inhibited by grain size, total clay content, compaction and cementation. Thus, special attention should be paid to these inhibiting factors to reduce risk in petroleum exploration within the area.

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