Use Of Digital Terrain Model Research Articles

Systematic review on the use of digital terrain models in dam rupture simulations

The study of hypothetical dam failure simulates the flow of the volume released by a dam in partial or total collapse. The calculations of wave propagation over the ground downstream of the eroded dam are performed by fluid hydrodynamic simulation programs. In this sense, the input data of the simulation model can be summarized in the physical characteristics of the fluid, the propagation hydrograph and the digital terrain model (DTM). Thus, this systematic review aimed to seek current bibliographic sources around the topic of simulation of hypothetical dam failures, with emphasis on the topographic representation of the valley through which the wave propagates, as a subsidy for simulating the failure of Dam B1, in Brumadinho, MG, Brazil. The results were classified according to categories in order to better differentiate the multidisciplinary content of the topic addressed.

Geoheritage and geodiversity elements of the SW Pacific: A conceptual framework

The Soutwest (SW) Pacific is an expansive oceanic region with many of its islands difficult to access and relatively unexplored in a geoheritage context. Here we provide a potential framework for systematically assessing geoheritage values of the SW Pacific and creating a holistic and multi-value inventory. We outline the use of digital terrain models as landform classification tools, and other newly available spatial data. While New Zealand is scientifically and culturally recognised as part of the SW Pacific, due to its large landmass and significant scientific data already available, here we excluded it from our analysis. Rather, the aim of our ongoing research is to provide the first comprehensive overview of the geoheritage potential and unique characteristics of small island nations of the SW Pacific. Only those islands were included in this study where geoheritage research has been initiated and include islands reflecting a good spectrum of geodiversity such as Vanuatu (Ambrym, Ambae, Lopevi, Kuwae group, Tanna), Tonga (Tongatapu, Tofua), and Samoa (Savai’i and Upolu). In a geotectonic context the SW Pacific sits on the western extremity of the large Pacific plate, resulting in a broad array of geotectonic situations where convergent plate boundary processes govern the broad geological evolution and geomorphological processes seen on the islands of our study area. Volcanism associated with plate boundaries is one of the most characteristic and recognisable geological processes linked with the region in the public perception of the area. Volcanism is associated with arc-type geosystems forming complex and compound polygenetic volcanism which offers unique geological-geomorphological elements shaping geodiversity of the region. In addition, these volcanic processes have shaped human communities since the earliest days of their establishment. The interaction of Polynesian societies with volcanism provides a unique geocultural perspective based on accumulated oral traditions, forming the basis of cultural practices that remain part of everyday life into the 21st century.

The influence of Strzelin Quarry Lakes on small reservoir retention resources in the regional catchments

The paper presents the results of the analysis of the volume of water retained in Strzelin Quarry Lakes (SQLs). The volume of retained water was estimated by using the computational method, where the proposed reduction factors were determined with the use of DTM (digital terrain model). 2.6 hm3 of water was retained in seventeen Strzelin Quarry Lakes, of which 1.2 hm3 in the Ślęza River catchment (3 quarry lakes), and 1.4 hm3 in the Oława River catchment (14 quarry lakes). The obtained data of the volume of water retained in SQLs were compared to the balance of the water retention capacity of water reservoirs in the catchments of the Ślęza River (0.809 hm3), part of the WR08 Bystrzyca balance catchments (16.190 hm3) and in the catchments of the Oława River (2.782 hm3), part of the WR09 Nysa Kłodzka balance catchment (104.960 hm3). Inclusion the volume of water retained in Strzelin Quarry Lakes in the small scale water retention (reservoirs and ponds) balance would increase the volume of retained water by 156.0% in the Ślęza catchment (by 7.8% in the WR08 Bystrzyca balance catchment) and by 49.5% in the Oława catchment (by 1,3% in the WR09 Nysa Kłodzka balance catchment). Under favorable hydrogeological and geomorphological conditions water reclamation of the excavations may be one of the main aspects of increasing the retention capacity of the catchment, what is particularly important in areas characterized by low water resources.

Contribution of GIS and Remote Sensing to Study and Analyze the Physiographic Characteristics of the Oued El-Abid Watershed (Central High Atlas, Morocco)

The present research describes the contribution of geomatic science in extracting, analyzing, mapping and determining the physiographic characteristics of the watershed of Oued El-Abid located in Central High Atlas, Morocco, which covers an area of 6405 km 2 and a perimeter of 527 km. The methodology adopted in this work is based on the use of digital terrain model (DTM) from SRTM images of 30*30 m resolution to identify and characterize the watershed and a Landsat 8 satellite image taken in August 2019, which leads us to calculate the physiographic and geometric characteristics of the watershed such as its shape, relief, geology, land use and hydrographic network. The results obtained show that the basin has an elongated shape with a moderate relief. The hypsometric view reveals that high altitude zones (1563 to 2763 m) are mainly distributed in the center and the southeast of the basin and the low altitudes are located in the west of the basin. This distribution of altitudes is related to the topography of the watershed. The hydrological view shows that the hydrographic network has a medium hierarchy while the typological aspect of the main river is about 6 (Lc= 203.17 Km). Also, the geological analysis reveals that the basin is mainly constituted by the Dogger and Lias terrains represented by limestone and marl formations, and the Cretaceous terrains represented by marl, marl and sandstone formations. The lithological nature of the basin is marked by permeable rocks (56%) constituted essentially by the carbonated, karstified and fractured mass.

Геоинформационные карты рельефа Северо-Востока Азии как основа изучения морфологии речных бассейнов

Цель. Создать первые геоинформационные карты горного рельефа Северо-Востока Азии и получить на этой основе морфологические характеристики водосборов, как имеющихся в информационных источниках, так и новых с оценкой точности и уровня корреляционных связей между ними. Материалы и методы. На их основании сравнительного анализа методов количественной морфометрии рельефа Северо-Востока Азии (аэрофотоснимки, карты, ГИС технологии) установлена перспективность расширения информационной базы с помощью геоинформационных карт. Применение цифровых моделей рельефа наиболее важно для слабо изученных бассейнов малых рек, данные о которых отсутствуют в справочно-фондовых источниках. Выбранная универсальная программа ArcGIS, версии 10.4, дает возможность получить так же принципиально новые параметры водосборных площадей горных рек. В связи с этим цифровая карта с высотными отметками рельефа земной поверхности (SRTM) и послужила исходным материалом для расчета различных морфометрических характеристик водосборов (например, площади и средние высоты водосборов, длину водотоков и т. д.). Результаты и обсуждение. Статистический анализ величин площадей водосборов, на основе геоинформационных карт (программа ArcGIS, версия 10.4) и растровых аналогов свидетельствует о незначительном их отличии (–3.9 to +3.0 %). Показана перспективность применения цифровых моделей рельефа для получения совершенно новых характеристик бассейнов рек, отсутствующих в известных источниках информации (например, форм, периметров, уклонов средних высот, и. т. д.). Кроме того, на основе статистического анализа дана оценка параметров различных водосборов и их частей (верховье, низовье), например, неоднородность поверхности долин рек и водоразделов. В дополнении указанном выше, установлена тесная, или, в отдельных случаях, функциональная связь между некоторыми характеристиками водосборов (например, уклоны – средние высоты). Выводы. Построенные впервые цифровые модели горного рельефа Северо-Востока Азии (программа ArcGIS, версия 10.4) позволили с достаточной точностью вычислить основные морфометрические параметры водосборов рек. Использование цифровых карт с высотами земной поверхности, в частности, SRTM, дали возможность получить принципиально новые, по сравнению с имеющимся уровнем изученности, параметры бассейнов водотоков, необходимые для науки и практики.

The Use of Digital Terrain Models to Estimate the Pace of Filling the Pit of a Central European Granite Quarry with Water

This paper presents the results of an analysis of the pace of filling one of the deepest European granite quarries with water. A DTM (digital terrain model) based on data from LiDAR ALS (light detection and ranging airborne laser scanning) was used to create a model of the pit of the Strzelin I granite quarry and to determine the reach and surface area of the direct catchment of the excavation pit. The increase in the volume of water in the excavation pit was determined. Analogue maps and DTM were used to calculate the maximum depth of the pit (113.3 m), its surface area (9.71 ha), and its capacity (5.1 million m3). The volume of water collected in the excavation pit during the years 2011–2018 was determined based on the analogue base map and the DTM. The result was 0.335 million m3. Based on the data made available by the mining company, the correlation of the DTM with the orthophotomap of the mining area and additional field measurements, the ordinates of the water level in the years 2011–2018 were determined. Initially, the water surface level in the quarry was located on the ordinate of 66.6 m a.s.l. (July 20, 2011). After the pumping of water was discontinued, the level rose to 96.1 m a.s.l. (January 28, 2018). The increase in the water volume in the quarry pit during specific periods was determined (actual retention increase). The obtained data on the volume of the retained water referred to the period during which it accumulated in the quarry. On average, the net increase in water retention in the excavation pit was 138.537 m3∙d−1, and the calculated net supply from the direct catchment (16.04 ha) was 101.758 m3∙d−1. The use of DTM and measurements of the water level in the excavation pit seem to be an efficient means of estimating the pace of spontaneous filling of the quarry with water supplied from the direct physiographic catchment.

Il sito medievale di Montecorvino (FG) e il suo territorio. Analisi spaziali in ambiente GIS Open Source

Since 2016, the Montecorvino project has studied the topics of intervisibility and of the movement of humans and goods in the area of Monti Dauni (Foggia, South-Eastern Italy) in the late Middle Ages. This has been accomplished through the use of spatial analysis in an Open Source GIS. The use of Digital Terrain Models in a hilly area has been crucial in analyzing the influence of geo-morphological contexts on the genesis and development of settlements. Single and cumulative viewshed analyses have been applied to figure out if and to what extent these settlements could keep sight of each other, their surroundings and the communication routes. By means of a cost surface analysis, some site catchment areas have been defined and the potential and easiest (least costly) paths between some of these settlements have been generated. The results have then been integrated into a much wider research-field, which features archaeological, historical and bibliographical sources of information, to produce a comprehensive and integrated study of the ancient landscapes.

Hydrographic network extraction and watersheds delimitation software of the South Oran (North Wester Algeria)

The development of space technology has allowed a better understanding and effective use of water resources through the use of Digital Terrain Models (DTM) Mapping the river system from DTM has two objectives, namely identifying first topography descriptors like hills, ridges and valleys of watersheds and second hydrological parameters to map areas of runoff recovery for a more efficient development and also a better representation of the actual land occupation. Our work is part of a methodological approach to satellite imagery processing and mapping of topographic and hydrographic parameters of watersheds. Thus, from DTM one was able to extract the full river system of the region. The results show a remarkable evolution of human activities and especially in areas of high water recovery capacity. Keywords : remote sensing, DTM, network hydrology, geographic, steppe, west of Algeria.

Geomorfologia estrutural, morfotectônica e morfometria da folha Cartagena 1:100.000–Colômbia

Este trabajo presenta una nueva caracterización geomorfológica de la región de Cartagena de Indias (Plancha 23 igac), se ha elaborado una cartografía morfoestructural, morfométrica y tectónica. Desde el punto de vista geomorfológico, el relieve está dominado por la presencia de dos cinturones rocosos estructurales: la Serranía de San Jacinto y la Serranía del Sinú. El primer cinturón, se localiza en el sector oriental de la zona y se compone principalmente de rocas sedimentarias de la Formación San Cayetano del Paleoceno, que desarrollan cimas de filos de gran altura. El Cinturón de la Serranía del Sinú, se presenta al oeste del Cinturón de San Jacinto, separado por la falla Villa Nueva - El Totumo. Allí se presenta la formación geológica más antigua del área de edad Oligoceno-Mioceno. Los sectores de menor relieve corresponden a las planicies y formas suavemente inclinadas y onduladas compuestas por depósitos no consolidados de tipo aluvial y coluvial de edad cuaternario. A partir de la interpretación de imágenes de satélite de tipo óptico y de radar y el uso de modelos digitales de terreno, en conjunto con las observaciones de campo, análisis de perfiles topográficos y la cartografía geomorfológica, se puede concluir que la tectónica cenozoica es el factor más importante en la configuración del relieve en la zona, que se evidencia por la configuración morfométrica de la red de drenaje.

Airborne LiDAR point cloud in mapping of fluvial forms: a case study of a Hungarian floodplain

The aim of this paper was to analyze the ground and low vegetation points of a Light Detection and Ranging (LiDAR) point cloud from the aspect of the generated digital terrain model (DTM). We determined the height difference between the surveyed surface and the DTM and the level of interspersion of ground and low vegetation points in a floodplain. Finally, we performed a supervised classification with topographic (elevation, slope and aspect) variables and an Normalized Difference Vegetation Index (NDVI) layer to identify swales and point bars as floodplain forms. Cross sections of field surveys provided reference data to express the magnitude of the bias on the DTM caused by the vegetation, and we proved that the bias can reach the 60% of the relative height and depth of the floodplain forms (mean error was 0.15 ± 0.12 m). A landscape metric, the Aggregation Index, provided an appropriate tool to analyze and quantify the interspersion of the ground and vegetation points: indicating a high level of interspersion of the classified points, i.e. proved that vegetation points where the last echoes reflected from the vegetation became ground points. Floodplain classification performed best with the common use of DTM, slope, aspect and NDVI coverages, with 71% overall accuracy.

Time-lapse photography for monitoring reservoir leakages (Montejaque dam, Andalusia, southern Spain)

AbstractA methodology based on the use of time-lapse photographs is presented to evaluate the leakages over time of a reservoir (Montejaque dam, Málaga Province, Spain) that feeds a karstic aquifer. In particular, photographic control allows the evolution of water levels in the dam and the river that feeds it to be monitored. Through changes in water volume, which are calculated from the level differences, daily leakages are evaluated, and the relationship between leakages and the water level of the reservoir is established. The proposed method includes adjusting the hydric balance and the use of digital terrain model and climate data. The inputs (river flow and direct precipitation) and other outputs (direct evaporation) are also evaluated. Values between 4 m3/s and 0.35 m3/s are obtained for the reservoir infiltration, clearly superior to the values obtained at the time of the construction of the dam in the 1920s. Mobilisation of the filling of fractures and conduits in karstic massif and calcite dissolution are processes that can influence this behaviour. When the water level is very low, the obtained values are below the historical leakages due to deposition of clay sediments at the reservoir bottom.

Regional surface morphology of comet 67P/Churyumov-Gerasimenko from Rosetta/OSIRIS images: The southern hemisphere

Aims. The OSIRIS camera on board the Rosetta spacecraft has been acquiring images of the comet 67P/Churyumov-Gerasimenko (67P)’s nucleus since August 2014. Starting in May 2015, the southern hemisphere gradually became illuminated and was imaged for the first time. Here we present the regional morphology of the southern hemisphere, which serves as a companion to an earlier paper that presented the regional morphology of the northern hemisphere. Methods. We used OSIRIS images that were acquired at orbits ~45−125 km from the center of the comet (corresponding to spatial resolutions of ~0.8 to 2.3 m/pixel) coupled with the use of digital terrain models to define the different regions on the surface, and identify structural boundaries accurately. Results. Seven regions have been defined in the southern hemisphere bringing the total number of defined regions on the surface of the nucleus to 26. These classifications are mainly based on morphological and/or topographic boundaries. The southern hemisphere shows a remarkable dichotomy with its northern counterpart mainly because of the absence of wide-scale smooth terrains, dust coatings and large unambiguous depressions. As a result, the southern hemisphere closely resembles previously identified consolidated regions. An assessment of the overall morphology of comet 67P suggests that the comet’s two lobes show surface heterogeneities manifested in different physical/mechanical characteristics, possibly extending to local (i.e., within a single region) scales.

3D GIS BASED EVALUATION OF THE AVAILABLE SIGHT DISTANCE TO ASSESS SAFETY OF URBAN ROADS

Abstract. The available sight distance (ASD) in front of the driver to detect possible conflicts with unexpected obstacles is fundamental for traffic safety. In the last 20 years, road design software (RDS) has been continuously updated with dedicated modules to estimate ASD, thus assessing the quality of project from a safety point of view. Unfortunately, the evaluation of ASD still represents an issue in the case of existing road, and the object of discussion in the research community. To avoid problems related to the limitation associated with the use of digital terrain models typically employed in RDS, the Geographic Information Systems (GIS) software can use digital surface models (DSM) which are more flexible in the modelling of sight obstruction due to vegetation, street furniture, and vertical surfaces largely diffused in urbanized areas. The paper deals with the evaluation of GIS in the estimation of ASD in a typical urban road where the density of sight obstruction along the roadside is relatively high. The work explores the case study of a collector road in the city of Turin (Italy). Results confirm the potentiality of GIS software in capturing the complex morphology of the urban environment, thus confirming that GIS could become an important analysis tool for road engineers in the field of road safety. The investigation here described is part of the Pro-VISION Project (funded in 2014 by the Regione Piemonte, Italy).

Landform Monitoring and Warning Framework Based on Time Series Modeling of Topographic Databases

Global Positioning System (GPS) and geodetic control networks are used today for analyzing and monitoring time-dependent crustal deformations, providing a series of accurate positional measurements to deliver information on positional changes and deformations that have occurred. Still, such networks present a low-resolution dispersal of positional measures, and do not take into account various physical constraints that affect the terrain’s seismic behavior. An alternative form of spatio-temporal infrastructure that is feasible and practical to establish might involve the use of Digital Terrain Model (DTM) databases. These databases use higher positional resolutions, and are exhibiting an increasing level of positional and height accuracy. Still, when comparing temporal DTMs, the separation of actual physical phenomena from data-related ambiguities is essential in the framework of spatio-temporal analysis. This paper proposes the use of a hierarchical co-modeling of different DTM databases for the task of landform monitoring. Analyses showed promising results, pointing to the feasibility of the proposed methodology in monitoring and quantifying topographic-related spatio-temporal phenomena, such as landslides and change detection, thus facilitating a reliable and precise landform monitoring and warning framework for geomorphodynamic analyses.

SHIA_Landslide: a distributed conceptual and physically based model to forecast the temporal and spatial occurrence of shallow landslides triggered by rainfall in tropical and mountainous basins

Landslides are a main cause of human and economic losses worldwide. For this reason, landslide hazard assessment and the capacity to predict this phenomenon have been topics of great interest within the scientific community for the implementation of early warning systems. Although several models have been proposed to forecast shallow landslides triggered by rainfall, few models have incorporated geotechnical factors into a complete hydrological model of a basin that can simulate the storage and movement of rainwater through the soil profile. These basin and full hydrological models have adopted a physically based approach. This paper develops a conceptual and physically based model called open and distributed hydrological simulation and landslides—SHIA_Landslide (Simulacion HIdrologica Abierta, or SHIA, in Spanish)—that is supported by geotechnical and hydrological features occurring on a basin-wide scale in tropical and mountainous terrains. SHIA_Landslide is an original and significant contribution that offers a new perspective with which to analyse shallow landslide processes by incorporating a comprehensive distributed hydrological tank model that includes water storage in the soil coupled with a classical analysis of infinite slope stability under saturated conditions. SHIA_Landslide can be distinguished by the following: (i) its capacity to capture surface topography and effects concerning the subsurface flow; (ii) its use of digital terrain model (DTM) to establish the relationships among cells, geomorphological parameters, slope angle, direction, etc.; (iii) its continuous simulation of rainfall data over long periods and event simulations of specific storms; (iv) its consideration of the effects of horizontal and vertical flow; and (vi) its inclusion of a hydrologically complete water process that allows for hydrological calibration. SHIA_Landslide can be combined with real-time rainfall data and implemented in early warning systems.

Use of digital terrain models in morphometric analysis of tectonic structures and prospecting of placers of alluvial genesis

Approaches have been developed to the application of the geomorphometric method for identification of neotectonic structures from maps of datum and summit planes by using the territory of Perm krai as an example. We carried out a comparative analysis of the resulting maps with existing neotectonic maps of local uplifts to reveal their good correlation. We substantiate the possibility of using the suggested approaches in forecasting deposits of sand-gravel raw materials.

The Use of Digital Terrain Model in the Study of Distribution of Cultural Landscape Elements based on the Example of Silesia Beskid

Abstract Digital Terrain Model (DTM) and maps based on it, are very valuable tool in investigations of distribution of cultural landscape elements. Connection DTM with a digital land cover maps, clearly illustrate factors determinate location of various landscape elements. The paper presents the applicability of Digital Terrain Model to detect the influence of topographic attributes on landscape elements distribution and to determinate the landscape’s structure in the different altitudinal zones. Presented results, are the effect of the first phase of cultural landscape elements distribution research and they are starting point to look for other factors which could effect on structure of the landscape.

Solar resources estimation combining digital terrain models and satellite images techniques

One of the most important steps to make use of any renewable energy is to perform an accurate estimation of the resource that has to be exploited. In the designing process of both active and passive solar energy systems, radiation data is required for the site, with proper spatial resolution. Generally, a radiometric stations network is used in this evaluation, but when they are too dispersed or not available for the study area, satellite images can be utilized as indirect solar radiation measurements. Although satellite images cover wide areas with a good acquisition frequency they usually have a poor spatial resolution limited by the size of the image pixel, and irradiation must be interpolated to evaluate solar irradiation at a sub-pixel scale. When pixels are located in flat and homogeneous areas, correlation of solar irradiation is relatively high, and classic interpolation can provide a good estimation. However, in complex topography zones, data interpolation is not adequate and the use of Digital Terrain Model ( DTM) information can be helpful. In this work, daily solar irradiation is estimated for a wide mountainous area using a combination of Meteosat satellite images and a DTM, with the advantage of avoiding the necessity of ground measurements. This methodology utilizes a modified Heliosat-2 model, and applies for all sky conditions; it also introduces a horizon calculation of the DTM points and accounts for the effect of snow covers. Model performance has been evaluated against data measured in 12 radiometric stations, with results in terms of the Root Mean Square Error ( RMSE) of 10%, and a Mean Bias Error ( MBE) of +2%, both expressed as a percentage of the mean value measured.

Three-dimensional mapping of a landslide using a multi-geophysical approach: the Quesnel Forks landslide

A landslide located on the Quesnel River in British Columbia, Canada is used as a case study to demonstrate the utility of a multi-geophysical approach to subsurface mapping of unstable slopes. Ground penetrating radar (GPR), direct current (DC) resistivity and seismic reflection and refraction surveys were conducted over the landslide and adjacent terrain. Geophysical data were interpreted based on stratigraphic and geomorphologic observations, including the use of digital terrain models (DTMs), and then integrated into a 3-dimensional model. GPR surveys yielded high-resolution data that were correlated with stratigraphic units to a maximum depth of 25 m. DC electrical resistivity offered limited data on specific units but was effective for resolving stratigraphic relationships between units to a maximum depth of 40 m. Seismic surveys were primarily used to obtain unit boundaries up to a depth of >80 m. Surfaces of rupture and separation were successfully identified by GPR and DC electrical resistivity techniques.

Generation of Digital Orthophotos from IKONOS Satellite Images

Due to its high spatial resolution, IKONOS imagery has the highest potential for large-scale topographic mapping of the resource satellites currently available. The orthorectification of IKONOS images thus becomes an important task. Since raw image data would, in general, not be provided by the satellite company, we have developed a method that performs the rectification of IKONOS GEO images. The proposed scheme includes the following steps: (1) the correction of relief displacement for ground control points (GCPs); (2) the performing of affine transformation between the ground coordinate system and the image coordinate system; (3) the performing of back projection for each pixel in the orthoimage; (4) the use of digital terrain model to calculate the relief displacement for the pixel in the previous step; and (5) image resampling. The experimental results indicate that the generated orthoimage may reach an accuracy of 2 m, when 6 GCPs are used.