Fault rupture in Baribis Fault possibly related to the 1847 major earthquake event in the Cirebon area

Abstract Baribis Fault is a recently identified active fault known to have thrust movement which located along the northern part of the West Java area. This E-W striking fault runs across high-populated areas, including Cirebon, Indramayu, Sumedang, and Subang area (with a probability of continuing to Jakarta and Banten areas). The last major historical earthquake occurred on November 16th, 1847 around the fault line with a radius of shaking area up to 400 km. The available high-resolution Digital Elevation Model from Geospatial Information Agency, called DEMNAS, has about 7.5-m grid data resolution but still not adequate to be used for identifying fault ruptures of this event. Hence, we conducted an Unmanned Aerial Vehicle (UAV) 3D Photogrammetry survey flown in the lower latitude (~100-m high) in the suspected sites. This study identified clear fault scarp associated with stream-valley offsets indicating strike-slip movement in the Ujung Jaya subdistrict, Sumedang. The trace of fault rupture has a 5±1-meter sinistral offset. This sharp fault deformation feature is possibly related to the 1847 earthquake in this area. This fact is different from regional morphology, which shows that the Baribis Fault is a thrust. Further study is necessary to get more detailed and precise information.

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Terrain-Based Shadow Correction Method for Assessing Supraglacial Features on the Greenland Ice Sheet

Frontiers in Remote Sensing ◽

10.3389/frsen.2021.690474 ◽

2021 ◽

Vol 2 ◽

Author(s):

Sasha. Z. Leidman ◽

Åsa K. Rennermalm ◽

Richard G. Lathrop ◽

Matthew. G. Cooper

Keyword(s):

Land Surface ◽

Greenland Ice Sheet ◽

Correction Method ◽

Correction Coefficient ◽

Digital Elevation ◽

Aerial Vehicle ◽

Sediment Cover ◽

Elevation Model ◽

Uav Images ◽

Gis Software

The presence of shadows in remotely sensed images can reduce the accuracy of land surface classifications. Commonly used methods for removing shadows often use multi-spectral image analysis techniques that perform poorly for dark objects, complex geometric models, or shaded relief methods that do not account for shadows cast on adjacent terrain. Here we present a new method of removing topographic shadows using readily available GIS software. The method corrects for cast shadows, reduces the amount of over-correction, and can be performed on imagery of any spectral resolution. We demonstrate this method using imagery collected with an uncrewed aerial vehicle (UAV) over a supraglacial stream catchment in southwest Greenland. The structure-from-motion digital elevation model showed highly variable topography resulting in substantial shadowing and variable reflectance values for similar surface types. The distribution of bare ice, sediment, and water within the catchment was determined using a supervised classification scheme applied to the corrected and original UAV images. The correction resulted in an insignificant change in overall classification accuracy, however, visual inspection showed that the corrected classification more closely followed the expected distribution of classes indicating that shadow correction can aid in identification of glaciological features hidden within shadowed regions. Shadow correction also caused a substantial decrease in the areal coverage of dark sediment. Sediment cover was highly dependent on the degree of shadow correction (k coefficient), yet, for a correction coefficient optimized to maximize shadow brightness without over-exposing illuminated surfaces, terrain correction resulted in a 49% decrease in the area covered by sediment and a 29% increase in the area covered by water. Shadow correction therefore reduces the overestimation of the dark surface coverage due to shadowing and is a useful tool for investigating supraglacial processes and land cover change over a wide variety of complex terrain.

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Rockfall Risk Analysis Based on Precise Topography using UAV

Korean Society of Hazard Mitigation ◽

10.9798/kosham.2020.20.4.63 ◽

2020 ◽

Vol 20 (4) ◽

pp. 63-73

Author(s):

Jaehee Choi ◽

Namgyun Kim ◽

Bongjin Choe ◽

Byonghee Jun

Keyword(s):

Point Cloud Data ◽

University Campus ◽

Digital Map ◽

Cloud Data ◽

The Road ◽

Mountainous Regions ◽

Digital Elevation ◽

Surface Models ◽

Aerial Vehicle ◽

Elevation Model

In this study, the risk of rockfall on incision slopes adjacent to roads was evaluated using the RocFall program. The study area was a slope adjacent to the road leading to a university campus in Samcheok-si, Gangwon-do, with an area of 774 m2 and an average slope of approximately 43°. A rock shed was installed at the lower zone of the slope. A 3D model of the terrain was generated based on point cloud data gathered using a UAV (unmanned aerial vehicle). Fast and accurate orthoimages were captured by UAV and high-resolution digital surface models (DSMs) were produced; these data were used to assess the risk of rockfall. Compared to terrain extraction using a digital elevation model (DEM) generated from an existing digital map, terrain extraction using a UAV was more effective in deriving results close to the actual situation in the field, especially for the analysis of rockfall jump height and kinetic energy. The necessity of constructing 3D topographic data using UAVs to predict rockfall disasters in mountainous regions was confirmed.

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Controller for a Low-Altitude Fixed-Wing UAV on an Embedded System to Assess Specific Environmental Conditions

International Journal of Aerospace Engineering ◽

10.1155/2020/1360702 ◽

2020 ◽

Vol 2020 ◽

pp. 1-10

Author(s):

Johannes von Eichel-Streiber ◽

Christoph Weber ◽

Jesús Rodrigo-Comino ◽

Jens Altenburg

Keyword(s):

Embedded System ◽

Environmental Conditions ◽

Plant Density ◽

Future Research ◽

Digital Elevation ◽

Small Uav ◽

Aerial Vehicle ◽

Low Costs ◽

Low Altitude ◽

Elevation Model

The use of an appropriate sensor on an unmanned aerial vehicle (UAV) is vital to assess specific environmental conditions successfully. In addition, technicians and scientists also appreciate a platform to carry the sensors with some advantages such as the low costs or easy pilot management. However, extra requirements like a low-altitude flight are necessary for special applications such as plant density or rice yield. A rotary UAV matches this requirement, but the flight endurance is too short for large areas. Therefore, in this article, a fixed-wing UAV is used, which is more appropriate because of its longer flight endurance. It is necessary to develop an own controller system to use special sensors such as Lidar or Radar on the platform as a multifunctionality system. Thereby, these sensors are used to generate a digital elevation model and also as a collision avoidance sensor at the same time. To achieve this goal, a small UAV was equipped with a hardware platform including a microcontroller and sensors. After testing the system and simulation, the controller was converted into program code to implement it on the microcontroller. After that, several real flights were performed to validate the controller and sensors. We demonstrated that the system is able to work and match the high requirements for future research.

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DEMNAS: MODEL DIGITAL KETINGGIAN NASIONAL UNTUK APLIKASI KEPESISIRAN

OSEANA ◽

10.14203/oseana.2018.vol.43no.4.2 ◽

2018 ◽

Vol 43 (4) ◽

Author(s):

Marindah Yulia Iswari ◽

Kasih Anggraini

Keyword(s):

Remote Sensing ◽

Digital Elevation Model ◽

Spatial Resolution ◽

Digital Data ◽

Coastal Hazards ◽

Remote Sensing Images ◽

Geospatial Information ◽

Digital Elevation ◽

Elevation Data ◽

Elevation Model

DEMNAS : NATIONAL DIGITAL ELEVATION MODEL FOR COASTAL APPLICATION. DEM is a digital data which contain information about elevation. In Indonesia, DEM can be generated from elevation points or contours in RBI (Rupabumi Indonesia). DEM can be performed to research of coastal application i.e. inundation or tsunami. DEM can help to analyze vulnerability or evacuation zone for coastal hazards. DEMNAS is one product of BIG (Geospatial Information Agency) which consist of elevation data from remote sensing images. DEMNAS data has not been widely used and is still being developed but DEMNAS has an advantage of spatial resolution. DEMNAS has spatial resolution 0.27 arc-second, which is bigger than the spatial resolution of global DEM.

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Quality of Digital Elevation Models obtained from Unmanned Aerial Vehicles for Precision Viticulture

OENO One ◽

10.20870/oeno-one.2016.50.4.1177 ◽

2016 ◽

Vol 50 (3) ◽

Author(s):

Léo Pichon ◽

Arnaud Ducanchez ◽

Hélène Fonta ◽

Bruno Tisseyre

Keyword(s):

Low Cost ◽

Wine Industry ◽

Image Capture ◽

Digital Elevation ◽

Elevation Data ◽

Aerial Vehicle ◽

Elevation Model ◽

Uav Images ◽

Data Acquisition And Processing

Aims: This work aims to study the quality of low cost Digital Surface Models (DSMs) obtained with Unmanned Aerial Vehicle (UAV) images and to test whether these DSMs meet common requirements of the wine industry.Methods and results: Experiments were carried out on a 4-ha vineyard located 10 km north of Beziers (France). The experimental site presents slope and aspect variations representative of mechanised commercial vineyards in Languedoc Roussillon. DSMs were provided by three UAV companies selected for the diversity of their solutions in terms of image capture altitude, type of UAV and image processing software. DSMs were obtained by photogrammetry and correspond to commercial products usually delivered by UAV companies. DSMs from UAV were compared to a reference Digital Elevation Model (DEM) acquired by a laser tachymeter. Four indicators were used to test the quality of DSMs: the mean error and its dispersion in the XY plane and in elevation Z. Results show a good georeferencing of the DSMs (MeanErrorXY<10 cm) and a similar quality in elevation (MeanErrorZ<10 cm) estimation. Results also show that the error in elevation is highly spatially structured. The spatial patterns observed did not depend on the elevation and could be related to algorithms used to compute the DSMs.Conclusion: Data acquisition and processing methods have an impact on the quality of the DSMs provided by the UAV companies. DSM qualities are good enough to meet commercial vineyard requirements. The tested DSMs fit the requirements to assess field characteristics (elevation, slope, aspects) which may be important for terroir characterisation purposes.Significance and impact of the study: This study proves that elevation data derived from UAV present an accuracy equivalent to the reference system used in this study. The rapidity, the low cost and the high spatial resolution of these data offer significant opportunities for the development of new services for the wine industry for field characterisation.

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Analisis Spasial Bencana Longsor Bukit Telogolele Kabupaten Banjarnegara Menggunakan Data Foto Udara UAV

Jurnal Nasional Teknologi Terapan (JNTT) ◽

10.22146/jntt.34089 ◽

2017 ◽

Vol 1 (1) ◽

pp. 77

Author(s):

Ruli Andaru ◽

Purnama Budi Santosa

Keyword(s):

Spatial Data ◽

3D Analysis ◽

Geospatial Information ◽

Aerial Photos ◽

Vehicle Data ◽

Digital Elevation ◽

Before And After ◽

Elevation Model ◽

Digital Orthophoto ◽

Map Data

Spatial data is a very important role in emergency command and disaster management, before, during or post disasters. When a disaster occurs, the currently geospatial information is very needed: where the center of the disaster, the area affected, the volumetric of the landslide, what facilities are damaged, and determine the location of temporary shelters. This study examines and analyze the landslide in Banjarnegara 2014 before and after the landslide using Peta Rupa Bumi Indonesia (RBI) and the UAV Aerial Photos (Unmanned Aerial Vehicle). Data before the landslide obtained from RBI, while data after landslide obtained by performing aerial photography using fixed-wing UAV in December 2014 and August 2015. These aerial photos processing with photogrammetry to produce digital orthophoto and DEM (Digital Elevation Model). Orthophoto and DEM data is used to perform geospatial analysis in both 2D and 3D. 3D analysis obtained from the extraction of DEM elevation map data values appearance of the earth (RBI) and the UAV Aerial Photo. Analysis was conducted on the four components: contouring, terrain profile/cross section, slope/gradient, and volumetric (cut and fill). Readiness management of geospatial data and information is necessary to minimize losses and speed up the process of rehabilitation and reconstruction in the areas affected by the disaster. With this spatial analysis, the estimated of volume of landslides, mapping the facility affected, and the manufacture of the soil profile (high landslide, landslide affected area) can be performed quickly and accurately.

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Localized extension in megathrust hanging wall following great earthquakes in western Nepal

Scientific Reports ◽

10.1038/s41598-021-00297-4 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Magali Riesner ◽

Laurent Bollinger ◽

Judith Hubbard ◽

Cyrielle Guérin ◽

Marthe Lefèvre ◽

...

Keyword(s):

High Resolution ◽

Hanging Wall ◽

Ground Surface ◽

Normal Fault ◽

Fault Scarp ◽

Fault System ◽

Digital Elevation ◽

Thrust Zone ◽

Elevation Model ◽

Short Time

AbstractThe largest (M8+) known earthquakes in the Himalaya have ruptured the upper locked section of the Main Himalayan Thrust zone, offsetting the ground surface along the Main Frontal Thrust at the range front. However, out-of-sequence active structures have received less attention. One of the most impressive examples of such faults is the active fault that generally follows the surface trace of the Main Boundary Thrust (MBT). This fault has generated a clear geomorphological signature of recent deformation in eastern and western Nepal, as well as further west in India. We focus on western Nepal, between the municipalities of Surkhet and Gorahi where this fault is well expressed. Although the fault system as a whole is accommodating contraction, across most of its length, this particular fault appears geomorphologically as a normal fault, indicating crustal extension in the hanging wall of the MHT. We focus this study on the reactivation of the MBT along the Surkhet-Gorahi segment of the surface trace of the newly named Reactivated Boundary Fault, which is ~ 120 km long. We first generate a high-resolution Digital Elevation Model from triplets of high-resolution Pleiades images and use this to map the fault scarp and its geomorphological lateral variation. For most of its length, normal motion slip is observed with a dip varying between 20° and 60° and a maximum cumulative vertical offset of 27 m. We then present evidence for recent normal faulting in a trench located in the village of Sukhetal. Radiocarbon dating of detrital charcoals sampled in the hanging wall of the fault, including the main colluvial wedge and overlying sedimentary layers, suggest that the last event occurred in the early sixteenth century. This period saw the devastating 1505 earthquake, which produced ~ 23 m of slip on the Main Frontal Thrust. Linked or not, the ruptures on the MFT and MBT happened within a short time period compared to the centuries of quiescence of the faults that followed. We suggest that episodic normal-sense activity of the MBT could be related to large earthquakes rupturing the MFT, given its proximity, the sense of motion, and the large distance that separates the MBT from the downdip end of the locked fault zone of the MHT fault system. We discuss these results and their implications for the frontal Himalayan thrust system.

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Landform monitoring in active volcano by UAV and SfM-MVS technique

ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences ◽

10.5194/isprsarchives-xl-8-71-2014 ◽

2014 ◽

Vol XL-8 ◽

pp. 71-75 ◽

Cited By ~ 21

Author(s):

T. Nakano ◽

I. Kamiya ◽

M. Tobita ◽

J. Iwahashi ◽

H. Nakajima

Keyword(s):

Active Volcano ◽

New Techniques ◽

Aerial Photo Interpretation ◽

Ogasawara Islands ◽

First Case ◽

Digital Elevation ◽

Aerial Vehicle ◽

Elevation Model ◽

D Model ◽

Area And Volume

Nishinoshima volcano in Ogasawara Islands has erupted since November, 2013. This volcanic eruption formed and enlarged a new island, and fused the new island with the old Nishinoshima Island. We performed automated aerial photographing using an Unmanned Aerial Vehicle (UAV) over the joined Nishinoshima Island on March 22 and July 4, 2014. We produced ortho-mosaic photos and digital elevation model (DEM) data by new photogrammetry software with computer vision technique, i.e. Structure from Motion (SfM) for estimating the photographic position of the camera and Multi-view Stereo (MVS) for generating the 3-D model. We also estimated the area and volume of the new island via analysis of ortho-mosaic photo and DEM data. Transition of volume estimated from the UAV photographing and other photographing shows the volcanic activity still keeps from initial level. The ortho-mosaic photos and DEM data were utilized to create an aerial photo interpretation map and a 3-D map. These operations revealed new knowledge and problems to be solved on the photographing and analysis using UAV and new techniques as this was first case in some respects.

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Visualizations of the Doblar Accumulation Basin Based on the UAV Survey

Advances in Cartography and GIScience of the ICA ◽

10.5194/ica-adv-1-8-2019 ◽

2019 ◽

Vol 1 ◽

pp. 1-7

Author(s):

Klemen Kozmus Trajkovski ◽

Gašper Štebe ◽

Dušan Petrovič

Keyword(s):

3D Model ◽

Weather Conditions ◽

Point Clouds ◽

Water Levels ◽

Contour Lines ◽

Digital Elevation ◽

Short Period ◽

Dense Point ◽

Aerial Vehicle ◽

Elevation Model

Abstract. Our research is based on a large case study of Unmanned Aerial Vehicle (UAV) surveys, modelling and visualizations of the Doblar accumulation basin. The various approaches for UAV surveying of large, demanding terrain configurations, and the benefits of surveying products used as a basis for other interdisciplinary hydrological and environmental services were researched. The demanding mountainous terrain, the steep slopes and deep and narrow streams required detailed pre-planning of the survey, including the pre-survey terrain overview. The accumulation basin was emptied merely for a short period; thus, the survey was performed in unfavourable weather conditions, which included coldness, snowfall and wind. Point clouds were generated and georeferenced from the 4377 recorded photos. The dense point cloud contained approximately 222 million points in the medium setting and more than a billion in the high setting. A 3D model was built from the data. This became the basis for numerous further analyses and for the presentation using cartographic principles: a digital elevation model with a resolution of 10&thinsp;cm, an orthophoto with a resolution of 10&thinsp;cm, a 3D model draped with orthophoto, contour lines with a 1&thinsp;m interval, topographic profiles, calculations of volumes at different water levels, a flythrough, augmented reality and a video simulation of the water level changes. The model can also serve as a basis for hydraulic and environmental analysis and simulations or used for analyses of the accumulation and deposition of river material compared with previous and future surveys.

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Digital Segusio: from models generation to urban reconstruction

Virtual Archaeology Review ◽

10.4995/var.2016.5874 ◽

2016 ◽

Vol 7 (15) ◽

pp. 87

Author(s):

Antonia Spanò ◽

Filiberto Chiabrando ◽

Livio Dezzani ◽

Antonio Prencipe

Keyword(s):

Laser Scanning ◽

Urban Landscape ◽

Geographical Information ◽

Innovative Methods ◽

Digital Elevation ◽

History Of ◽

Land Survey ◽

Aerial Vehicle ◽

Elevation Model ◽

The City

The reconstructive study of the urban arrangement of Susa in the 4th century arose from the intention to exploit some resources derived from local studies, and survey activities, fulfilled by innovative methods from which the modelling of architectural heritage (AH) and virtual reconstructions are derived. The digital Segusio presented in this paper is the result of intensive discussion and exchange of data and information during the urban landscape documentation activities, and due to the technology of virtual model generation, making it possible to recreate the charm of an ancient landscape. The land survey has been accomplished using aerial and terrestrial acquisition systems, mainly through digital photogrammetry from UAV (Unmanned Aerial Vehicle) and terrestrial laser scanning. Results obtained from both the methods have been integrated into the medium scale geographical data from the regional map repository, and some processing and visualization supported by GIS (Geographical Information System) has been achieved. Subsequently, with the help of accurate and detailed DEM (Digital Elevation Model) and other architectural scale models related to the ancient heritage, this ancient landscape was modelled. The integration of the history of this city with digital and multimedia resources will be offered to the public in the city museum housed in the restored castle of Maria Adelaide (Savoy dynasty, 11th century), which stands in the place where the acropolis of the city of Susa lay in ancient times.

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