A building or edifice is an enclosed structure with a roof and walls, usually standing permanently in one place, such as a house or factory. Buildings come in a variety of sizes, shapes, and functions, and have been adapted throughout history for numerous factors, from building materials available, to weather conditions, land prices, ground conditions, specific uses, prestige, and aesthetic reasons. To better understand the concept, see Nonbuilding structure for contrast.
Brine is water with a high-concentration solution of salt. In diverse contexts, brine may refer to the salt solutions ranging from about 3.5% up to about 26%. Brine forms naturally due to evaporation of ground saline water but it is also generated in the mining of sodium chloride. Brine is used for food processing and cooking, for de-icing of roads and other structures, and in a number of technological processes. It is also a by-product of many industrial processes, such as desalination, so it requires wastewater treatment for proper disposal or further utilization.
Interferometry is a technique which uses the interference of superimposed waves to extract information. Interferometry typically uses electromagnetic waves and is an important investigative technique in the fields of astronomy, fiber optics, engineering metrology, optical metrology, oceanography, seismology, spectroscopy, quantum mechanics, nuclear and particle physics, plasma physics, biomolecular interactions, surface profiling, microfluidics, mechanical stress/strain measurement, velocimetry, optometry, and making holograms.
Subsidence is a general term for downward vertical movement of the Earth's surface, which can be caused by both natural processes and human activities. Subsidence involves little or no horizontal movement, which distinguishes it from slope movement.
In mathematics, the continuous wavelet transform (CWT) is a formal tool that provides an overcomplete representation of a signal by letting the translation and scale parameter of the wavelets vary continuously.
A geologic hazard or geohazard is an adverse geologic condition capable of causing widespread damage or loss of property and life. These hazards are geological and environmental conditions and involve long-term or short-term geological processes. Geohazards can be relatively small features, but they can also attain huge dimensions and affect local and regional socio-economics to a large extent.
Satellite geodesy is geodesy by means of artificial satellites—the measurement of the form and dimensions of Earth, the location of objects on its surface and the figure of the Earth's gravity field by means of artificial satellite techniques. It belongs to the broader field of space geodesy. Traditional astronomical geodesy is not commonly considered a part of satellite geodesy, although there is considerable overlap between the techniques.
In the field of hydrogeology, storage properties are physical properties that characterize the capacity of an aquifer to release groundwater. These properties are storativity (S), specific storage (Ss) and specific yield (Sy). According to Groundwater, by Freeze and Cherry (1979), specific storage, [m−1], of a saturated aquifer is defined as the volume of water that a unit volume of the aquifer releases from storage under a unit decline in hydraulic head.
Dam safety systems are used to monitor the state of dams, including external physical threats to the dams, and issuing emergency warnings at various degrees of automation. This includes the use of differential GPS and SAR remote sensing to monitor the risks imposed by landslides and subsidence. For large dams, seismographs are used to detect reservoir-induced seismicity that could threaten the stability of the dam. The output of these systems can provide warning to the local population ahead of a potential collapse.
Earth observation (EO) is the gathering of information about the physical, chemical, and biological systems of the planet Earth. It can be performed via remote-sensing technologies or through direct-contact sensors in ground-based or airborne platforms.
Structure from motion (SfM) is a photogrammetric range imaging technique for estimating three-dimensional structures from two-dimensional image sequences that may be coupled with local motion signals. It is studied in the fields of computer vision and visual perception.
Interferometric synthetic aperture radar, abbreviated InSAR, is a radar technique used in geodesy and remote sensing. This geodetic method uses two or more synthetic aperture radar (SAR) images to generate maps of surface deformation or digital elevation, using differences in the phase of the waves returning to the satellite or aircraft. The technique can potentially measure millimetre-scale changes in deformation over spans of days to years. It has applications for geophysical monitoring of natural hazards, for example earthquakes, volcanoes and landslides, and in structural engineering, in particular monitoring of subsidence and structural stability.
Richard M. "Dick" Goldstein is an American radar astronomer and planetary scientist, who has been called "The Father of Radar Interferometry."
A multi-component gas analyzer system (Multi-GAS) is an instrument package used to take real-time high-resolution measurements of volcanic gases. A Multi-GAS package includes an infrared spectrometer for CO2, two electrochemical sensors for SO2 and H2S, and pressure–temperature–humidity sensors, all in a weatherproof box. The system can be used for individual surveys or set up as permanent stations connected to radio transmitters for transmission of data from remote locations. The instrument package is portable, and its operation and data analysis are simple enough to be conducted by non-specialists.
Paz is a Spanish Earth observation and reconnaissance satellite launched on 22 February 2018. It is Spain's first spy satellite. The satellite is operated by Hisdesat. Paz was previously referred to as SEOSAR.
This is a compilation of the properties of different analog materials used to simulate deformational processes in structural geology. Such experiments are often called analog or analogue models. The organization of this page follows the review of rock analog materials in structural geology and tectonics of Reber et al. 2020.
Avik Bhattacharya is a professor at the Centre of Studies in Resources Engineering, Indian Institute of Technology Bombay, Mumbai, India. He has been working in the field of radar polarimetry theory and applications for more than a decade. His main focuses on the use of synthetic aperture radar (SAR) data for land use classification, change detection and qualitative and quantitative biophysical and geophysical information estimation.
The Altiplano-Puna Magma Body (APMB), a magma body located within the Altiplano-Puna plateau approximately 10–20 km beneath the Altiplano-Puna Volcanic Complex (APVC) in the Central Andes. High resolution tomography shows that this magma body has a diameter of ~200 km, a depth of 14–20 km, with a total volume of ~500,000 km3, making it the largest known active magma body on Earth. Thickness estimates for the APMB are varied, with some as low as 1 km, others around 10–20 km, and some extending as far down as the Moho. The APMB is primarily composed of 7-10 wt% water andesitic melts and the upper portion may contain more dacitic melts with partial melt percentages ranging from 10-40%. Measurements indicate that the region around the Uturuncu volcano in Bolivia is uplifting at a rate of ~10 mm/year, surrounded by a large region of subsidence. This movement is likely a result of the APMB interacting with the surrounding rock and causing deformation. Recent research demonstrates that this uplift rate may fluctuate over months or years and that it has decreased over the past decade. Various techniques, such as seismic, gravity, and electromagnetic measurements have been used to image the low-velocity zone in the mid to upper crust known as the APMB.
Geological structure measurement by LiDAR technology is a remote sensing method applied in structural geology. It enables monitoring and characterisation of rock bodies. This method's typical use is to acquire high resolution structural and deformational data for identifying geological hazards risk, such as assessing rockfall risks or studying pre-earthquake deformation signs.
Atmospheric correction for Interferometric Synthetic ApertureRadar (InSAR) technique is a set of different methods to remove artefact displacement from an interferogram caused by the effect of weather variables such as humidity, temperature, and pressure. An interferogram is generated by processing two synthetic-aperture radar images before and after a geophysical event like an earthquake. Corrections for atmospheric variations are an important stage of InSAR data processing in many study areas to measure surface displacement because relative humidity differences of 20% can cause inaccuracies of 10–14 cm InSAR due to varying delays in the radar signal. Overall, atmospheric correction methods can be divided into two categories: a) Using Atmospheric Phase Screen (APS) statistical properties and b) Using auxiliary (external) data such as GPS measurements, multi-spectral observations, local meteorological models, and global atmospheric models.
