scholarly journals Electrical features of deep structures of Southern Tuscany (Italy)

1998 ◽  
Vol 41 (3) ◽  
Author(s):  
A. Fiordelisi ◽  
R. Mackie ◽  
A. Manzella ◽  
D. Watts ◽  
A. Zaja
Keyword(s):  
Data Modelling ◽  
Remote Site ◽  
Magnetotelluric Data ◽  
Geothermal Fields ◽  
Geophysical Techniques ◽  
Tectonically Active ◽  
Local Reference ◽  
The Cost ◽  
Cultural Noise ◽  
Anomalous Condition

Over the last six years, magnetotelluric data were acquired at 86 sites covering much of Southern Tuscany. Twenty-four of these sites were acquired in single-site or local-reference mode, whereas 62 were aquired in very-remote-reference mode, with a remote site located on Capraia Island í 40 km from the cost í where the cultural noise is very low. The data modelling showed that Southern Tuscany is characterized by a fairly uniform middle-lower crust that has a resistivity of a few thousand W ·m below 10 km. At shallower depths in the crust, the resistivity is closer to values around 500 W ·m. This uniformity is interrupted only below the Larderello and Mt. Amiata geothermal fields where deep conductive bodies are believed to exist. A general anomalous condition can hence be depicted for this region, with low resistivity values typical of those in tectonically active areas as opposed to more resistive values typical in continental areas. These data and those from other geophysical techniques suggest that these conductive zones may be associated with hot material coming from deeper sources below the geothermal areas.

The Application of Ground Conductivity and Offset Wenner Resistivity Soundings to Optimise the Investigation of a 300 ha Site in the West Midlands

1986 ◽  
Vol 2 (1) ◽  
pp. 241-245
Author(s):  
F. B. Frost ◽  
J. P. Dumble
Keyword(s):  
General Structure ◽  
The West ◽  
Geological Surveys ◽  
Buried Channel ◽  
West Midlands ◽  
Geophysical Techniques ◽  
Sand And Gravel ◽  
The Cost ◽  
Surface Geology ◽  
Ground Conductivity

AbstractIn order to evaluate quickly and cost effectively the detailed shallow sub-surface geology of a 300 ha area in the West Midlands, geophysical techniques were used in conjunction with shell and auger drilling. Since the area contains one of the largest landfill sites of its type in Europe and is crossed by a river which is abstracted for drinking water within a short distance downstream, it was important to determine the geology and hydrogeology in some detail.Previous geological surveys of the area, which included the drilling of over 80 boreholes for sand and gravel extraction, indicated the presence of up to 5 m of highly variable sandy overburden overlying Keuper Marl. It was apparent from an initial desk study that despite the large number of boreholes the geology had been completely misinterpreted.A ground conductivity map was produced using a Geonics EM-31 which rapidly gave a picture of the general structure and identified targets for drilling and Offset Wenner resistivity soundings. The geophysics revealed the presence of a major buried channel cutting deeply into the marl, which was later confirmed in several places by drilling. Surface outcrops of clay or marl could be identified using the ground conductivity values alone.The use of the geophysical techniques has considerably reduced the cost and time of the investigation and has allowed the major effort to be concentrated in problem areas.

scholarly journals Relationship between seismicity and active faults in Thanh Hoa province detected by local seismic network

2021 ◽  
Vol 43 (2) ◽  
pp. 199-219
Author(s):  
Duong T. N. ◽  
Lai Hop Phong ◽  
Pham D. N. ◽  
Chen C. H. ◽  
Dinh V. T.
Keyword(s):  
Seismic Activity ◽  
Active Faults ◽  
Seismic Network ◽  
Local Network ◽  
Ground Acceleration ◽  
Magnetotelluric Data ◽  
Seismogenic Source ◽  
Tectonically Active ◽  
Relationship Of ◽  
The Relationship

Thanh Hoa province belongs to the southwest part of Northwest Vietnam, which is considered a tectonically active region. In the area of Thanh Hoa province, there are three deep-seated tectonic faults, namely Son La-Bim Son, Song Ma, and Sop Cop. As predicted by scientists, these faults are capable of producing credible earthquakes that might be the strongest in the territory of Vietnam. Besides the three main seismogenic sources, in the province, there are other smaller active faults such as Thuong Xuan-Ba Thuoc and Thuong Xuan-Vinh Loc but the relationship of these faults with seismic activity is still rather blurred. This may due to the sparseness of the Vietnamese National Seismic Network which can not record adequately small earthquakes in the area. This paper presents new results of additional monitoring from a local seismic network using 12 Guralp - 6TD broadband seismometers that have been deployed in Thanh Hoa province since November 2009. We found that the Thanh Hoa area is not seismically quiet. The average number of earthquakes recorded by the network has reached 80 - 90 events per year and some of them have magnitude from ML 3.0 to 4.0.By integration of the earthquake epicenters derived from the local network and distribution of active faults, we can detect several earthquakes locating near the three active faults, not only along the main faults but also along its subsidiary faults. We focused on the active faults of Thuong Xuan-Ba Thuoc and Thuong Xuan-Vinh Loc by using the recent results of the gravity, seismic, and magnetotelluric data analyses. Several recorded earthquakes distribute along the two small faults and some of them reach magnitude 3.0 or greater on the ML scale. In this study, the Thuong Xuan-Vinh Loc is recognized as a seismogenic source. To identify seismic hazard potential caused by earthquakes generated from the active faults, segmentation of the Thuong Xuan - Ba Thuoc fault had been done based on geological and geomorphological indications and seismic activity, and then the peak ground acceleration was determined for each fault segment. Besides, a large number of earthquake epicenters do not have a good correlation with a specific fault, especially in the area of Thanh Hoa coastal plain, which is covered by thick layers of Neogene - Quaternary sediment. This shows that there may be hidden active faults in the area which are needed to study further.

scholarly journals Relationship between seismicity and active faults in Thanh Hoa province detected by local seismic network

2021 ◽  
Vol 43 (2) ◽  
Author(s):  
Duong T. N. ◽  
Lai Hop Phong ◽  
Pham D. N. ◽  
Chen C. H. ◽  
Dinh V. T.
Keyword(s):  
Seismic Activity ◽  
Active Faults ◽  
Seismic Network ◽  
Local Network ◽  
Ground Acceleration ◽  
Magnetotelluric Data ◽  
Seismogenic Source ◽  
Tectonically Active ◽  
Relationship Of ◽  
The Relationship

Thanh Hoa province belongs to the southwest part of Northwest Vietnam, which is considered a tectonically active region. In the area of Thanh Hoa province, there are three deep-seated tectonic faults, namely Son La-Bim Son, Song Ma, and Sop Cop. As predicted by scientists, these faults are capable of producing credible earthquakes that might be the strongest in the territory of Vietnam. Besides the three main seismogenic sources, in the province, there are other smaller active faults such as Thuong Xuan-Ba Thuoc and Thuong Xuan-Vinh Loc but the relationship of these faults with seismic activity is still rather blurred. This may due to the sparseness of the Vietnamese National Seismic Network which can not record adequately small earthquakes in the area. This paper presents new results of additional monitoring from a local seismic network using 12 Guralp - 6TD broadband seismometers that have been deployed in Thanh Hoa province since November 2009. We found that the Thanh Hoa area is not seismically quiet. The average number of earthquakes recorded by the network has reached 80 - 90 events per year and some of them have magnitude from ML 3.0 to 4.0.By integration of the earthquake epicenters derived from the local network and distribution of active faults, we can detect several earthquakes locating near the three active faults, not only along the main faults but also along its subsidiary faults. We focused on the active faults of Thuong Xuan-Ba Thuoc and Thuong Xuan-Vinh Loc by using the recent results of the gravity, seismic, and magnetotelluric data analyses. Several recorded earthquakes distribute along the two small faults and some of them reach magnitude 3.0 or greater on the ML scale. In this study, the Thuong Xuan-Vinh Loc is recognized as a seismogenic source. To identify seismic hazard potential caused by earthquakes generated from the active faults, segmentation of the Thuong Xuan - Ba Thuoc fault had been done based on geological and geomorphological indications and seismic activity, and then the peak ground acceleration was determined for each fault segment. Besides, a large number of earthquake epicenters do not have a good correlation with a specific fault, especially in the area of Thanh Hoa coastal plain, which is covered by thick layers of Neogene - Quaternary sediment. This shows that there may be hidden active faults in the area which are needed to study further.

scholarly journals Analysis of Remote Sensing, Gravity, and Magnetotelluric Data on Geothermal Fields in Ogan Komering Ulu (OKU) District, South Sumatra

2020 ◽  
Vol 5 (1) ◽  
pp. 22-30
Author(s):  
Okta Dwi Puspita ◽  
Reinaldi Juniarto ◽  
Sava Sintya Larasati ◽  
Hafiz Hamdalah ◽  
Iqbal Takodama
Keyword(s):  
Remote Sensing ◽  
Magnetotelluric Data ◽  
Geothermal Fields

scholarly journals Basement Configuration Of Labuan Basin, Pandeglang, Based On Gravity Data

2020 ◽  
Vol 21 (2) ◽  
pp. 103
Author(s):  
Lina Handayani ◽  
Dadan Dani Wardhana
Keyword(s):  
Gravity Data ◽  
Bouguer Anomaly ◽  
Depth Estimation ◽  
Sediment Layer ◽  
Geological Hazards ◽  
Deep Basin ◽  
Geophysical Techniques ◽  
Gravity Measurements ◽  
Tectonically Active ◽  
Basement Depth

Pandeglang is located on the coast of the Sunda Strait, which is tectonically active as the source of geological hazards. Basement configuration mapping is required for further understanding in geological characteristic of the land. Gravity method is one of the geophysical techniques that can be applied for the regional subsurface characterization. Gravity measurements were completed in the Pandeglang area, from Tanjung Lesung to Labuan coastline and all passable roads in Pandeglang Regency. The Bouguer anomaly obtained has indicated a steady decreasing anomaly from south-southwest to north-northeast area. The result of residual anomalies analysis and basement depth estimation presented a deep basin in the northeast most of the study area (Labuan – Picung), which indicates a thick sediment layer in this area.Keywords: gravity anomaly, residual anomaly, basin, basement, Labuan, Pandeglang. 

The IBM-PC in electron microscopy

1996 ◽  
Vol 54 ◽  
pp. 612-613
Author(s):  
James F. Mancuso
Keyword(s):  
Head Start ◽  
Image Acquisition ◽  
Cost Effective ◽  
Financial Applications ◽  
Number Of Factors ◽  
Instrument Control ◽  
The Cost ◽  
Training And Support ◽  
Control Image ◽  
Ibm Pc

IBM PC compatible computers are widely used in microscopy for applications ranging from control to image acquisition and analysis. The choice of IBM-PC based systems over competing computer platforms can be based on technical merit alone or on a number of factors relating to economics, availability of peripherals, management dictum, or simple personal preference.IBM-PC got a strong “head start” by first dominating clerical, document processing and financial applications. The use of these computers spilled into the laboratory where the DOS based IBM-PC replaced mini-computers. Compared to minicomputer, the PC provided a more for cost-effective platform for applications in numerical analysis, engineering and design, instrument control, image acquisition and image processing. In addition, the sitewide use of a common PC platform could reduce the cost of training and support services relative to cases where many different computer platforms were used. This could be especially true for the microscopists who must use computers in both the laboratory and the office.

New Feasible Concepts of Aberration Correction for Realizing High-Resolution Electron Microscopes

1990 ◽  
Vol 48 (1) ◽  
pp. 202-203
Author(s):  
H. Rose
Keyword(s):  
Spherical Aberration ◽  
Wave Length ◽  
Electron Wave ◽  
Optical Lens ◽  
Resolution Electron ◽  
Rotationally Symmetric ◽  
Electron Microscopes ◽  
The Cost ◽  
Imaging Performance ◽  
Acceleration Voltage

The imaging performance of the light optical lens systems has reached such a degree of perfection that nowadays numerical apertures of about 1 can be utilized. Compared to this state of development the objective lenses of electron microscopes are rather poor allowing at most usable apertures somewhat smaller than 10-2 . This severe shortcoming is due to the unavoidable axial chromatic and spherical aberration of rotationally symmetric electron lenses employed so far in all electron microscopes.The resolution of such electron microscopes can only be improved by increasing the accelerating voltage which shortens the electron wave length. Unfortunately, this procedure is rather ineffective because the achievable gain in resolution is only proportional to λ1/4 for a fixed magnetic field strength determined by the magnetic saturation of the pole pieces. Moreover, increasing the acceleration voltage results in deleterious knock-on processes and in extreme difficulties to stabilize the high voltage. Last not least the cost increase exponentially with voltage.

An application: the cost of clinic care by undergraduate dental students and its relationship to clinic fees

1994 ◽  
Vol 58 (11) ◽  
pp. 832-835 ◽  
Author(s):  
ES Solomon ◽  
TK Hasegawa ◽  
JD Shulman ◽  
PO Walker
Keyword(s):  
Dental Students ◽  
The Cost

The effect of heliotherapy on the cost of psoriasis, p. 288

1998 ◽  
Vol 138 (2) ◽  
pp. 205-205
Author(s):  
Snellman ◽  
Maljanen ◽  
Aromaa ◽  
Reunanen ◽  
Jyrkinen‐Pakkasvirta ◽  
...  
Keyword(s):  
The Cost
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