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Scientific visualization of geospatial data provides highly effective tools for analysis and communication of information about the land surface and its features, properties, and temporal evolution. Whereas single-surface visualization of landscapes is now routinely used in presentation of Earth surface data, interactive 3D visualization based upon multiple elevation surfaces and cutting planes is gaining recognition as a powerful tool for analyzing landscape structure based on multiple return Light Detection and Ranging (LiDAR) data. This approach also provides valuable insights into land surface changes captured by multi-temporal elevation models. Thus, animations using 2D images and 3D views are becoming essential for communicating results of landscape monitoring and computer simulations of Earth processes. Multiple surfaces and 3D animations are also used to introduce novel concepts for visual analysis of terrain models derived from time-series of LiDAR data using multi-year core and envelope surfaces. Analysis of terrain evolution using voxel models and visualization of contour evolution using isosurfaces has potential for unique insights into geometric properties of rapidly evolving coastal landscapes. In addition to visualization on desktop computers, the coupling of GIS with new types of graphics hardware systems provides opportunities for cutting-edge applications of visualization for geomorphological research. These systems include tangible environments that facilitate intuitive 3D perception, interaction and collaboration. Application of the presented visualization techniques as supporting tools for analyses of landform evolution using airborne LiDAR data and open source geospatial software is illustrated by two case studies from North Carolina, USA., Pub. in Geomorphology, v137 p122 137, 2012.

Laser-induced breakdown spectroscopy (LIBS) offers a means of rapidly distinguishing different geographic sources for a mineral because the LIBS plasma emission spectrum provides information on the chemical composition (i.e. geochemical fingerprint) of a geomaterial. An application of this approach with potentially significant commercial and political importance is the spectral fingerprinting of conflict minerals such as columbite-tantalite (coltan). Following a successful pilot study of a columbite?tantalite suite from North America, a more geographically diverse set of 57 samples from 37 locations around the world was analyzed using a commercially available LIBS system. The LIBS spectra were analyzed using advanced multivariate statistical signal processing techniques. Partial least squares discriminant analysis (PLSDA) resulted in a correct place-level geographic classification at success rates above 90%. The possible role of rare-earth elements (REEs) as a factor contributing to the high levels of sample discrimination was explored. These results provide additional evidence that LIBS has the potential to be utilized in the field as a real-time screening tool to discriminate between columbite-tantalite ores of different provenance., Published in Spectrochimica Acta Part B, v74-75 p131-136, 2012.

Obsidian is a natural glass of volcanic origin and a primary resource used by indigenous peoples across North America for making tools. Geochemical studies of obsidian enhance understanding of artifact production and procurement and remain a priority activity within the archaeological community. Laser-induced breakdown spectroscopy (LIBS) is an analytical technique being examined as a means for identifying obsidian from different sources on the basis of its geochemical fingerprint. This study tested whether two major California obsidian centers could be distinguished from other obsidian localities and the extent to which subsources could be recognized within each of these centers. LIBS data sets were collected in two different spectral bands (350 130 nm and 690 115 nm) using a Nd:YAG 1064 nm laser operated at approx. 23 mJ, a Czerny-Turner spectrograph with 0.2-0.3 nm spectral resolution and a high performance imaging charge couple device (ICCD) detector. Classification of the samples was performed using partial least-squares discriminant analysis (PLSDA), a common chemometric technique for performing statistical regression on high-dimensional data. Discrimination of samples from the Coso Volcanic Field, Bodie Hills, and other major obsidian areas in north-central California was possible with an accuracy of greater than 90% using either spectral band., Published in Applied Optics, v51 n7 pB65-B73, 1 March 2012

This project demonstrated the ability of Desert Tortoise Canine (DTK9) teams to locate Mojave Desert tortoises in the field at natural population densities, with an emphasis on finding small size classes. DTK9s were shown to be successful at this task. DTK9 team technology was developed to assist Department of Defense (DoD) installations and other agencies to maintain environmental compliance and support delisting efforts for the federal and state listed Mojave Desert tortoise (Gopherus agassizii). Delisting the desert tortoise would alleviate conflict between training and testing on installations and environmental regulations. Delisting would reduce costs associated with regulatory compliance such as surveying, monitoring, translocation, and Head Start programs., The original document contains color images.

The ability to interrogate objects buried in soil and ascertain their chemical composition in-situ would be an important capability enhancement for both military and humanitarian demining. Laser-induced breakdown spectroscopy (LIBS) is a simple spark spectrochemical technique using a pulsed laser. Recent developments in broadband and man-portable LIBS provide the capability for the real-time detection of all elements at very high sensitivity in any target material. This technological advance offers a unique potential for the development of a rugged and reliable man-portable or robot-deployable chemical sensor that would be capable of both in-situ point probing and chemical sensing for land mine detection. In this study, broadband LIBS spectra were acquired under laboratory conditions for more than a dozen different types of antipersonnel and antitank land mine casings from four countries. A set of antitank land mine simulants was also acquired. Subsequently, a statistical classification technique (partial least-squares discriminant analysis) was used to discriminate land mine casings from the simulants and to assign "unknown" spectra to a mine type based upon a library classification approach. Overall, a correct classification success of 99.0% was achieved, with a misclassification rate of only 1.8%., The original document contains color images.

Laser-induced breakdown spectroscopy (LIBS) provides an alternative chemical analytical technique that obviates the issues of sample preparation and sample destruction common to most laboratory-based analytical methods. This contribution explores the capability of LIBS analysis to identify carbonate and silicate minerals rapidly and accurately. Fifty-two mineral samples (18 carbonates, 9 pyroxenes and pyroxenoids, 6 amphiboles, 8 phyllosilicates, and 11 feldspars) were analyzed by LIBS. Two composite broadband spectra (averages of 10 shots each) were calculated for each sample to produce two databases each containing the composite LIBS spectra for the same 52 mineral samples. By using correlation coefficients resulting from the regression of the intensities of pairs of LIBS spectra, all 52 minerals were correctly identified in the database. If the LIBS spectra of each sample were compared to a database containing the other 51 minerals, 65% were identified as a mineral of similar composition from the same mineral family. The remaining minerals were misidentified for two reasons: 1) the mineral had high concentrations of an element not present in the database; and 2) the mineral was identified as a mineral with similar elemental composition from a different family. For instance, the Ca-Mg carbonate dolomite was misidentified as the Ca-Mg silicate diopside. This pilot study suggests that LIBS has promise in mineral identification and in situ analysis of minerals that record geological processes., Published in Spectrochimica Acta Part B, v62 p1528-1536, 2007. Presented at the International Conference on Laser Induced Plasma Spectroscopy and Applications (4th), held in Montreal, Canada on 5-8 Sep 2006.

Laser-induced breakdown spectroscopy (LIBS) has been investigated for the detection of energetic materials. After an initial survey of explosives and propellants, key elemental and molecular emission lines in the LIBS spectra were identified. Techniques for improving the sensitivity and selectivity of LIBS for explosives detection, such as the use of an argon buffer gas and double pulse LIBS, have been investigated with laboratory and field-portable instruments. We present results demonstrating the ability of LIBS to discriminate between energetic and non-energetic materials., The original document contains color images.

Laser Induced Breakdown Spectroscopy (LIBS) is an emerging, minimally-destructive sensor technology for in-situ, real-time chemical species identification and analysis. The Army Research Laboratory has been engaged in LIBS analysis for over a decade and recently has been investigating the potential to apply broadband LIBS analysis to specific military problems, one of which is as a handheld, confirmatory sensor for land mine detection., See also ADM001736, Proceedings for the Army Science Conference (24th) Held on 29 November - 2 December 2004 in Orlando, Florida. The original document contains color images.

Army Regulation (AR) 70-38 publishes standards for temperature and humidity in different environments, but there are other important environmental features such as general climate, terrain character, and biological diversity, that are also important for successful army materiel testing and training. An initial tropical test site study was necessitated by the closure at the end of 1999 of all U.S. Army tropical testing and training facilities, which had been located in the Republic of Panama. In the process of searching for a replacement for the lost tropical testing facilities, the Army and its natural environment testing activity, Yuma Proving Ground (YPG), developed a better scientific understanding of how geographic analysis could enhance the Army's ability to test and train in a natural environmental setting. A list of 14 criteria was developed that characterizes any site as to its ability to support all testing missions. This list was initially employed to screen Hawaii and Puerto Rico for areas that could support components of the tropical testing mission. A similar approach was taken in analyzing current Army desert testing and training environments in a study that undertook detailed site characterizations of Yuma Proving Ground and the National Training Center (NTC) at Ft. Irwin., See also ADM001736, Proceedings of the Army Science Conference (24th) held in Orlando, FL on 29 Nov-2 Dec 2004.

When surveying an area for sea mines with a sidescan sonar, the ability to find the same object in two different sonar images is helpful to determine the nature of the object. The main problem with matching two sidescan sonar images is that a scene changes appearance when viewed from different viewpoints. This paper presents a novel approach for matching two sidescan sonar images. The method first registers the two images to ground, then uses the cross correlation of the object positions on the seabed to find the correct displacement between the two images. In order to correct any minor displacements of the relative objects position as a result of the ground registration, the object position is given an area of influence. The method is compared to an existing method for matching sidescan sonar images based on hypothetical reasoning. The two methods are compared on a number of real sidescan sonar images in which the displacement is already known, as well as on images taken of a scene from two different viewpoints. We conclude that the proposed method has fewer variables to tune in order to get satisfactory results, and that it gives better or equal results compared to the hypothetical reasoning method.