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Publication InSAR and its applications in geo-engineering: case studies with different platforms and sensorsZhou, Wendy; Lowry, Benjamin; Wnuk, Kendall; Liu, Linan; Gutierrez, MarteInSAR (Interferometric Synthetic Aperture Radar) is a microwave remote sensing technique that uses the phase shift of radar signals acquired at different timeframes to measure or monitor ground deformation. InSAR has many implications, such as monitoring ground deformation caused by natural- or geo-hazards, e.g., earthquakes, volcanoes, landslides, anthropogenic activities, groundwater pumping, underground mining, and hydrocarbon extraction. InSAR can also be utilized to study infrastructure displacements and environmental changes, such as monitoring changes in surface water level, mapping floods, soil moisture contents (at a shallow depth), and deforestation. The first significant application of SAR is the deployment of real-aperture radar interferometry to study the topography of the Moon in the early 1970s. However, InSAR was not widely used due to the limitations of computation capacity and the sparse availa-ble SAR data until the early 1990s. A major milestone for InSAR applications came in the 1990s when researchers used SAR data to measure ground deformation induced by the Landers Earthquake in California, and one of the publications landed on the cover of Nature magazine. This landmark achievement brought widespread recognition to the potential of InSAR for mapping ground deformation. Over the past two decades, the computation power and availability of SAR data have improved considerably with the launch of more satellites carrying SAR sensors. This paper presents a brief introduction to the history and fundamentals of InSAR, as well as case studies of its applications in the geo-engineering fields, including landslide displacement monitoring and underground excavation-induced ground subsidence mapping.Publication Permafrost(Colorado School of Mines. Arthur Lakes Library, 2018) Zhou, WendyPermafrost, or perennially frozen ground, is defined as soil or rock having temperatures below 0oC over at least two consecutive winters and the intervening summer. Much of the permafrost has been frozen since the Pleistocene time. Permafrost occurs in the Arctic, Antarctic and high alpine regions. About one-fifth of the total land area of the world is underlain by permafrost (Burdick et al. 1978). The top layer of the ground in which the temperature fluctuates above or below 0oC during the year is defined as the active layer (Andersland and Ladanyi 1994). Other terms such as seasonally frozen ground, seasonal frost and annually thawed layer are synonyms for the active layer. The thickness of this layer varies spatially and temporally. The upper boundary of permafrost is defined as the permafrost table. In the discontinuous permafrost zone, taliks form between the active layer and the permafrost table. Taliks, or unfrozen ground, are layers of ground that remain unfrozen throughout the year (Andersland and Ladanyi 1994). In the continuous permafrost zone, taliks often occur underneath shallow thermokarst lakes or rivers, where the water below a certain depth may not freeze in winter and, thus, the soil underneath will not freeze either. Other terms, such as thaw lake or cave-in lake, have also been used for a thermokarst lake. Open talik is an area of unfrozen ground that is open to the ground surface but otherwise enclosed in permafrost. Through talik is unfrozen ground that is exposed to the ground surface and to a larger mass of unfrozen ground beneath. Unfrozen ground encased in permafrost is known as a closed talik.Publication Aeromagnetic survey(Colorado School of Mines. Arthur Lakes Library, 2018) Zhou, WendyAn aeromagnetic survey (AMS) is an air-borne geophysical survey performed using a magnetometer aboard or towed behind an aircraft. A magnetometer is an instrument used to measure the magnetic field. Aeromagnetic surveys are probably one of the most common types of air-borne geophysical surveys. The applications of AMS in engineering geology include, but are not limited to, near-surface geological mapping, structural geology mapping, aiding three-dimension (3D) geological subsurface model construction, groundwater study, environmental study, and geologic hazards assessment. In an aeromagnetic survey, an airplane, flying at a low altitude, carrying a magnetic sensor flies back and forth in a grid-like pattern over an area, recording disturbances in the magnetic field (Fig. 1). Height and gridline spacing determine the resolution of the data. Geologic processes often bring together rocks with slightly different magnetic properties, and these variations cause very small magnetic fields above the Earth’s surface. The differences in the magnetic field are called “anomalies.” (Blakely et al. 1999).Publication GIS for natural resources (mineral, energy, and water)(Colorado School of Mines. Arthur Lakes Library, 2018) Zhou, Wendy; Minnick, Matthew D.; Cui, CelenaNatural resources embrace a broad array of categories, including agricultural, conservational, forestry, oceanic, water, energy, and mineral resources. This chapter only focuses on the latter three. Traditional methods for natural resource management include, but are not limited to, geophysical exploration, field geological mapping, geochemical analysis, and aero-photo interpretations. Natural resource related research is by nature a spatial problem. Integration of field survey data and other pertinent information can be a time-consuming task by traditional ways. With the help of GIS, most of the tasks can be conducted in ways that are nearly impossible in traditional methods. Three case studies of GIS application in natural resource analyses will be presented in this book chapter to demonstrate the GIS applications in compiling, integrating, analyzing and visualizing natural resource data.Publication GIS for earth sciences(Colorado School of Mines. Arthur Lakes Library, 2021) Zhou, WendyGeographic Information System (GIS) supports data collection, geospatial data analysis, visualization, scientific communication and research collaboration. GIS has implications for many fields of the Earth Sciences, which are about and beyond one’s imagination. Since the development of the first computerized GIS in the 1960s, the need by professionals for geospatial technology in fields that utilize geospatial data has never stopped expanding. As noted by a market analysis in August 2017: “The GIS Market was valued at USD 5.33 Billion in 2016 and is expected to reach USD 10.12 Billion by 2023, growing at a compound annual growth rate of 9.6% between 2017 and 2023.” (marketsandmarkets.com, August 2017). Earth Sciences encompasses a broad and diverse array of technical areas, such as geology, geomorphology, geography, geophysics, hydrology, hydrogeology, environmental sciences, oceanography, meteorology, and atmospheric sciences. All of these fields are using geospatial data to solve complex problems related to the planet Earth. Some of these problems are nearly impossible to solve without the use of GIS. This article presents a brief introduction to GIS and examples of its applications to the Earth sciences. Three case studies highlight the utility of GIS applications in compiling, integrating, analyzing and visualizing geospatial data.