Keywords: Mecanique des sols ; Drainage ; Ecoulement souterrain Reference Record created on 2004-09-07, modified on 2016-08-08

Applications of soil physics.

Advances in computing technology have fostered the development of new and powerful deep learning (DL) techniques, which have demonstrated promising results in a wide range of applications. Particularly, DL methods have been successfully used to classify remotely sensed data collected by Earth Observation (EO) instruments. Hyperspectral imaging (HSI) is a hot topic in remote sensing data analysis due to the vast amount of information comprised by this kind of images, which allows for a better characterization and exploitation of the Earth surface by combining rich spectral and spatial information. However, HSI poses major challenges for supervised classification methods due to the high dimensionality of the data and the limited availability of training samples. These issues, together with the high intraclass variability (and interclass similarity) –often present in HSI data– may hamper the effectiveness of classifiers. In order to solve these limitations, several DL-based architectures have been recently developed, exhibiting great potential in HSI data interpretation. This paper provides a comprehensive review of the current-state-of-the-art in DL for HSI classification, analyzing the strengths and weaknesses of the most widely used classifiers in the literature. For each discussed method, we provide quantitative results using several well-known and widely used HSI scenes, thus providing an exhaustive comparison of the discussed techniques. The paper concludes with some remarks and hints about future challenges in the application of DL techniques to HSI classification. The source codes of the methods discussed in this paper are available from: https://github.com/mhaut/hyperspectral_deeplearning_review .

Deep learning classifiers for hyperspectral imaging: A review

Details of Earth's shallow subsurface—a key component of the critical zone (CZ)—are largely obscured because making direct observations with sufficient density to capture natural characteristic spatial variability in physical properties is difficult. Yet this inaccessible region of the CZ is fundamental to processes that support ecosystems, society, and the environment. Geophysical methods provide a means for remotely examining CZ form and function over length scales that span centimeters to kilometers. Here we present a review highlighting the application of geophysical methods to CZ science research questions. In particular, we consider the application of geophysical methods to map the geometry of structural features such as regolith thickness, lithological boundaries, permafrost extent, snow thickness, or shallow root zones. Combined with knowledge of structure, we discuss how geophysical observations are used to understand CZ processes. Fluxes between snow, surface water, and groundwater affect weathering, groundwater resources, and chemical and nutrient exports to rivers. The exchange of gas between soil and the atmosphere have been studied using geophysical methods in wetland areas. Indirect geophysical methods are a natural and necessary complement to direct observations obtained by drilling or field mapping. Direct measurements should be used to calibrate geophysical estimates, which can then be used to extrapolate interpretations over larger areas or to monitor changing processes over time. Advances in geophysical instrumentation and computational approaches for integrating different types of data have great potential to fill gaps in our understanding of the shallow subsurface portion of the CZ and should be integrated where possible in future CZ research.

Multiscale geophysical imaging of the critical zone

https://scholarworks.boisestate.edu/cgi/viewcontent.cgi?article=1579&context=geo_facpubs

NASA's surface biology and geology designated observable: A perspective on surface imaging algorithms

Mapping ground deformation over Houston–Galveston, Texas using multi-temporal InSAR

The U.S. Geological Survey tested the utility of imaging spectroscopy (also referred to as hyperspectral remote sensing) as an aid to regional mineral exploration efforts in remote parts of Alaska. Airborne imaging spectrometer data were collected in 2014 over unmined porphyry Cu deposits in the eastern Alaska Range using the HyMapTM sensor. Maps of the distributions of predominant minerals, made by matching reflectance signatures in the remotely sensed data to reference spectra in the shortwave infrared region, do not uniquely discriminate individual rock units. However, they do highlight hydrothermal alteration associated with porphyry deposits and prospects hosted mostly within the Nabesna pluton. In and around porphyry Cu deposits at Orange Hill and Bond Creek, unique spectral signatures are related to variations in chlorite and white mica abundance and their chemical composition. This is best revealed in the longer-wavelength 2,200-nm Al-OH absorption feature positions in pixels spectrally dominated by white mica proximal to porphyry deposits. Similar spectral signatures of chlorite and white mica wavelength positions were also recognized away from the porphyry deposits; follow-up sampling identified these satellite areas to also contain Cu-Mo-Au mineralized rock. Our study confirms that airborne imaging spectroscopy has application for regional mineral exploration in exposed mountainous terrain in Alaska. Introduction Imaging spectroscopy (also referred to as hyperspectral remote sensing) is a technology that has been utilized with success for mapping vegetation and mineral abundances over many areas of the Earth’s surface (e.g., Clark et al., 2003; Kokaly et al., 2009, 2013). Spectroscopy can be used to identify certain minerals based on their electronic and vibrational absorptions in the reflected solar range (400–2,500 nm). While not effective in identifying many rock-forming minerals such as quartz, feldspars, and pyroxenes, the shortwave infrared (SWIR) region (2,000–2,500 nm) is key to identifying carbonates and hydrous minerals (e.g., micas and clays; Clark, 1999; Thompson et al., 1999; Swayze et al., 2014) that are often products of hydrothermal alteration. Aircraftor spacecraft-borne platforms are particularly effective for recognizing the spatial distributions of these minerals associated with important mineral deposit types (Crosta et al., 1998; van der Meer, 2006; Hubbard et al., 2007; Bedini, 2012; van Ruitenbeek et al., 2012; Mars, 2013). Most published studies have focused on areas at midlatitudes, with the technology infrequently applied at higher latitudes because data collection and analysis are more difficult due to short collection seasons and low sun angle resulting in poor solar illumination. Alaska is well known for its precious and base metal mines and mineral deposits. Major mines include the Pogo, Fort Knox, and Kensington Au deposits, the Greens Creek AgAu-Pb-Zn volcanogenic massive sulfide deposit, and the Red Dog Zn-Pb-Ag deposit. World-class deposits, including the Donlin Creek Au and the giant Pebble porphyry Cu-Au-Mo, remain undeveloped. It is likely that additional economic mineral resources will be discovered, and this drives continued exploration activities across the state (e.g., Freeman et al., 2015; Athey et al., 2016). However, the vast size, remoteness, and rugged terrain, coupled with a relatively short summer field season, hamper these efforts. New methods like remote imaging spectroscopy (hyperspectral surveying) could help assess large tracts of land and provide focused target areas for ground-based mineral exploration. The U.S. Geological Survey (USGS) conducted an airborne imaging spectroscopy study using the HyMap sensor to test this technology for mineral exploration at high latitudes in Alaska. The selected study area extends from the Nabesna Glacier to the Canadian border in Wrangell-St. Elias National Park, eastern Alaska Range (Fig. 1). This area was selected because (1) the region has reconnaissance-level geologic control based on historical USGS mapping (e.g., Richter, 1973; Richter et al., 1975a), (2) much of the uplands contain bedrock exposure for effective spectral mapping, and (3) the area includes several undisturbed porphyry Cu deposits and prospects. Porphyry deposits are typically characterized by broad alteration zones with distinctive mineralogy (e.g., Lowell and Guilbert, 1970; Seedorff et al., 2005; Sillitoe, 2010), including mineral(s) that can be remotely sensed using spectroscopy (e.g., Berger et al., 2003; John et al., 2010; Mars, 2013). These factors, along with reconnaissance ground sampling completed as part of this project, form a framework against which our imaging spectroscopy survey results can be compared and validated. In this paper, we present mapping results, including spectrally predominant mineral and mineral composition variability maps from the western part of the survey area that contains Submitted: May 16, 2017 Accepted: November 7, 2017 † Corresponding author: e-mail, ggraham@usgs.gov © 2018 Gold Open Access: this paper is published under the terms of the CC-BY license. Economic Geology, v. 113, no. 2, pp. 489–510 ISSN 0361-0128; doi: 10.5382/econgeo.2018.4559; 22 p. Supplementary files available online. 489

Application of Imaging Spectroscopy for Mineral Exploration in Alaska: A Study over Porphyry Cu Deposits in the Eastern Alaska Range

/pdf/airborne-electromagnetic-mapping-of-the-base-of-aquifer-in-39hfe9lyzp.pdf

Airborne electromagnetic mapping of the base of aquifer in areas of western Nebraska

: Protocols for mapping and characterizing land-use/land-cover (LULC) features in the riparian zone are presented in this report. Characterization of riparian systems is critical to a comprehensive understanding of nutrient enrichment effects on stream ecosystems because riparian functions provide an important ecological connection between surrounding land use activities and nutrient dynamics in small-to-medium-sized steams.

/pdf/protocols-for-mapping-and-characterizing-land-use-land-cover-4hp3eovghw.pdf

Protocols for mapping and characterizing land use/land cover in riparian zones

Bibliogov, United States, 2013. Paperback. Book Condition: New. 246 x 189 mm. Language: English . Brand New Book ***** Print on Demand *****.Since the early 1900s, groundwater has been the primary source of municipal, industrial, and agricultural water supplies for the Houston-Galveston region, Texas. The region s combination of hydrogeology and nearly century-long use of groundwater has resulted in one of the largest areas of subsidence in the United States; by 1979, as much as 3 meters (m) of subsidence...

Investigation of Land Subsidence in the Houston-Galveston Region of Texas By Using the Global Positioning System and Interferometric Synthetic Aperture Radar, 1993?2000

/pdf/estimated-land-surface-subsidence-in-harris-county-texas-49h193q6sl.pdf

Michaela R. Johnson

Papers

Application of Imaging Spectroscopy for Mineral Exploration in Alaska: A Study over Porphyry Cu Deposits in the Eastern Alaska Range

Airborne electromagnetic mapping of the base of aquifer in areas of western Nebraska

Protocols for mapping and characterizing land use/land cover in riparian zones

Investigation of Land Subsidence in the Houston-Galveston Region of Texas By Using the Global Positioning System and Interferometric Synthetic Aperture Radar, 1993?2000

Estimated land-surface subsidence in Harris County, Texas, 1915-17 to 2001