scholarly journals SEABED TOPOGRAPHY MAPPING IN SANGIHE TALAUD WATERS USING MULTIBEAM ECHOSOUNDER

Oseanika ◽  
2020 ◽  
Vol 1 (1) ◽  
Author(s):  
Dwi Haryanto ◽  
Muhamad Irfan ◽  
Taufan Wiguna ◽  
Hendra Kurnia Febriawan
Keyword(s):  
High Resolution ◽  
Multibeam Echosounder ◽  
The North ◽  
North Sulawesi ◽  
Marine Habitats ◽  
Seabed Topography ◽  
High Resolution Bathymetry ◽  
New Discovery

The application of multibeam echosounder for seabed topography has been developing rapidly. Multibeam echosounder is a very efficient way to get a wide seabed topography coverage for each ping, so it can produce high-resolution seabed topography maps. These maps can be used as a reference for further investigation or exploration, for example geological studies, marine habitats and others. RV Baruna Jaya IV is operated by Laboratory for Marine Survey Technology – BPPT that have been hull mounted equipped a Germany technology multibeam echosunder Seabeam 1050D system. The Seabeam 1050D allow to sweep measuring the seabed topography using 126 beams simultaneously from port to starboard sites. R.V. Baruna Jaya IV and the Okeanos Explorer of NOAA have been conducted joint Indonesia - U.S. Expedition to Sangihe Talaud waters (INDEX SATAL) in the north area of the North Sulawesi Province during July - August, 2010. Seabed topography of less than 2000 metres were recorded by Seabeam 1050D system, the area of larger depths of 2000 metres to 6000 metres recorded by Simrad EM-302 from Okeanos Explorer. The seabed topography in Sangihe Talaud waters has a varied seabed topography. The new discovery that showed on the map is a 1600 m height of seamount, risen up from the depth of 2300m to 710m. Others geological seabed can be identified according to high resolution bathymetry map resulted from this study.Keywords: multibeam echosounder, seabed topography, seamount, Sangihe Talaud

scholarly journals Towards a regional high-resolution bathymetry of the North West Shelf of Australia based on Sentinel-2 satellite images, 3D seismic surveys and historical datasets

2021 ◽  
Author(s):  
Ulysse Lebrec ◽  
Victorien Paumard ◽  
Michael J. O'Leary ◽  
Simon C. Lang
Keyword(s):  
High Resolution ◽  
3D Seismic ◽  
Seismic Surveys ◽  
North West ◽  
Marine Habitats ◽  
Digital Elevation ◽  
Elevation Model ◽  
High Resolution Bathymetry ◽  
Water Depths ◽  
Better Than

Abstract. High-resolution bathymetry is a critical dataset for marine geoscientists. It can be used to characterize the seafloor and its marine habitats, to understand past sedimentary records and even to support the development of offshore engineering projects. Most methods to acquire bathymetry data are costly and can only be practically deployed on relatively small areas. It is therefore critical to develop cost-effective and advanced techniques to produce large-scale bathymetry datasets. This paper presents an integrated workflow that builds on satellites images and 3D seismic surveys, integrated with historical depth soundings, to generate a regional high-resolution digital elevation model. The method was applied to the southern half of Australia's North West Shelf and led to the creation of a new high-resolution bathymetry, with a resolution of 10 × 10 m in nearshore areas and 30 × 30 m elsewhere. The vertical and spatial accuracy of the datasets have been thoroughly assessed using open source Laser Airborne Depth Sounder (LADS) and Multi Beam Echo Sounder (MBES) surveys as a reference. The comparison of the datasets indicates that the seismic-derived bathymetry has a vertical accuracy better than 1 m + 2 % of the absolute water depths, while the satellite-derived bathymetry has a depth accuracy better than 1 m + 5 % of the absolute water depths. This dataset constitutes a significant improvement of the pre-existing regional 250 × 250 m grid and will support the onset of research projects on costal morphologies, marine habitats, archaeology, and sedimentology. All datasets used as inputs are publicly available and the method is fully integrated in Python scripts making it readily applicable elsewhere in Australia and around the world. The workflow as well as the resulting bathymetry have been independently reviewed and approved for release by a technical committee from the AusSeabed Community (Geoscience Australia). The regional digital elevation model as well as the underlying datasets can be accessed at: https://doi.org/10.26186/144600.

scholarly journals High-Resolution North Sulawesi Drought Hazzard Mapping Based on Consecutive Dry Days (CDD)

2021 ◽  
Vol 893 (1) ◽  
pp. 012018
Author(s):  
A M Setiawan ◽  
A A Syafrianno ◽  
R Rahmat ◽  
Supari
Keyword(s):  
High Resolution ◽  
Global Climate ◽  
Annual Rainfall ◽  
Hazard Map ◽  
The North ◽  
North Sulawesi ◽  
Drought Hazard ◽  
Geostatistical Approach ◽  
Daily Precipitation Data ◽  
Consecutive Dry Days

Abstract North Sulawesi is one of the Province in northern Indonesia with high spatial annual rainfall variations and influenced by global climate anomaly that can lead to extreme events and disaster occurrence, such as flood, landslide, drought, etc. The purpose of this study is to generate high-resolution meteorological hazard map based on long-term historical consecutive dry days (CDD) over the North Sulawesi region. CDD was calculated based on observed daily precipitation data from Indonesia Agency for Meteorology, Climatology, and Geophysics (BMKG) surface observation station network (CDDobs) and the daily-improved Climate Hazards group Infrared Precipitation with Stations (CHIRPS) version 2.0 (CDDCHIRPS) during 1981 – 2010 period. The Japanese 55-year Reanalysis (JRA-55) data obtained from iTacs (Interactive Tool for Analysis of the Climate System) with the same time scale period also used to explain physical – dynamical atmospheric properties related to drought hazard over this region. The Geostatistical approach using regression kriging method was applied as spatial interpolation technique to generate high resolution gridded (0.05° × 0.05°) drought hazard map. This method combines a regression of CDDobs as dependent variable (target variable) on CDDCHIRPS as predictors with kriging of the prediction residuals. The results show that most of the areas were categorized as medium drought hazard level with CDD values ranging from 80-100 days. Meanwhile, small islands around main Sulawesi island such as Sangihe and Karakelong island are dominated by low drought hazard levels with CDD values ranging from 50-60 days. The highest levels of drought hazard area are located in South Bolaang Mongondow Regency.

scholarly journals MORPHOLOGICAL RESPONSE TO THE DEEP WATERWAY PROJECT AROUND THE CHANGJIANG ESTUARY, CHINA

2011 ◽  
Vol 1 (32) ◽  
pp. 11
Author(s):  
Lingzhi Pan ◽  
Pingxing Ding ◽  
Jianzhong Ge
Keyword(s):  
Sediment Transport ◽  
High Resolution ◽  
Phase I ◽  
Morphological Change ◽  
Changjiang Estuary ◽  
Morphological Response ◽  
The Changjiang Estuary ◽  
The North ◽  
High Resolution Bathymetry ◽  
Evolution Trend

Changjiang Estuary is characterized by complex branches and outlets (North Branch, North Channel, North Passage and South Passage). The relatively shallow bathymetry around the mouth limits the navigational potentials (Fig.1). The Deep Waterway Project (DWP) was carried out in the North Passage of South Channel for the purpose of deepening the navigational channel from 7.0m in July 1998 to 8.5m in July 2001 (Phase I), 10.0m in May 2005 (Phase II) and 12.5m in May 2010 (Liu et al. 2004). In addition to dredging, two dykes were constructed to reduce the sediment transport from Jiuduansha and Hengsha Shoals into North Passage. A set of groins was built with connection to dykes for the purpose of strengthening the currents in the middle of channel, which helps the maintenance of the navigational capability. The construction has significantly changed the local bathymetry in the Changjiang Estuary and within the channel. The high-resolution bathymetry measurements were made over seasons. An evolution trend of the morphological change is revealed, which is discussed in this paper.

scholarly journals Is the machecoul fault the source of the ∼M6 1799 Vendée earthquake (France)?

2021 ◽  
Author(s):  
C Kaub ◽  
L Geoffroy ◽  
L Bollinger ◽  
J Perrot ◽  
P Le Roy ◽  
...  
Keyword(s):  
High Resolution ◽  
Gravity Data ◽  
Normal Fault ◽  
Tectonic Activity ◽  
Macroseismic Data ◽  
The North ◽  
Seismogenic Source ◽  
Fault Trace ◽  
One Year ◽  
High Resolution Bathymetry

Summary The ∼M6 1799 Bouin earthquake is considered as one of the largest earthquakes to have struck Western France. However, the seismogenic source potentially responsible for this event remain marginally documented. We present results from a focused offshore-onshore multidisciplinary survey in its meizoseismal area in order to identify the fault segments that potentially ruptured during this earthquake. Based on macroseismic data and the geology, we focused our study on the so-called Machecoul Fault as a potential source of the 1799 Bouin event. Our survey includes extensive high-resolution seismic reflection, high resolution bathymetry and a one-year seismological survey. These data were combined with existing topography, onshore gravity data and drill data to document the geometry of the Marais Breton / Baie de Bourgneuf basin, the past tectonic activity and the current local microearthquakes at depth along its bounding faults. Offshore and onshore observations suggest a recent activity of the segmented Machecoul Fault bounding the basin to the North. Offshore, the planar contact between the Plio-Quaternary sediments and the basement along the fault trace as well as the thickening of these sedimentary units near this contact suggests tectonic control rather than erosion. Onshore, the recent incision of the footwall of the fault suggests a recent tectonic activity. The temporary local seismological experiment deployed between 2016 and 2017 recorded a diffuse micro-seismicity down to the depth of 22 +/-5 km along the southward dipping Machecoul Fault, associated with predominantly normal fault mechanisms. Altogether, these results suggest that the Machecoul Fault is a serious candidate for being the source of the historical Bouin 1799 earthquake.

scholarly journals A high-resolution solar spectrum 2000 Å–2200 Å

1970 ◽  
Vol 36 ◽  
pp. 271-273
Author(s):  
B. B. Jones ◽  
B. C. Boland ◽  
R. Wilson ◽  
S. T. F. Engstrom
Keyword(s):  
High Resolution ◽  
Solar Spectrum ◽  
Solar Image ◽  
Roll Control ◽  
North East ◽  
The North ◽  
Alignment System ◽  
Optical Alignment ◽  
South Axis ◽  
System Operating

A high-resolution solar spectrum in the range 2000–2200 Å was obtained in a recent flight of a sunpointing Skylark rocket. This was launched at 04.21 hr UT on April 22, 1969 from Woomera and reached an apogee of 178 km. An optical alignment system operating on the main vehicle pointing system gave a net stabilisation of ±3 arc sec in the position of the solar image relative to the spectrograph slit. The slit, of length 1.0 mm, was set in the north-east quadrant parallel to and 5 arc min from the north/south axis, its lower edge being 1 arc min from the equator. The roll control of ±2.5° was provided entirely by the standard Elliott Bros. type of vehicle stabilisation.

scholarly journals e-Navigating in highly-constrained waters: a case study of the Vistula Lagoon

2021 ◽  
pp. 1-10
Author(s):  
Adam Weintrit ◽  
Jacek Pietraszkiewicz ◽  
Wiesław Piotrzkowski ◽  
Wojciech Tycholiz
Keyword(s):  
High Resolution ◽  
Global Solution ◽  
Transition Process ◽  
Practical Implementation ◽  
Vistula Lagoon ◽  
Digital Era ◽  
High Resolution Bathymetry ◽  
Marine Navigation ◽  
The Vistula Lagoon

Abstract In recent years the transition of marine navigation to the digital era has been gaining momentum. Implementation of e-Navigation solutions varies from country to country in terms of their priorities, goals, levels and effects. Maritime authorities in Poland have been setting the pace in this transition process, not only in Poland but also in general as a global solution. The most recent example is the planned deployment of a variety of e-Navigation tools in the Vistula Lagoon: from GNSS-RTK Ground-Based Augmentation System, to virtual and synthetic aids to navigation, high-resolution bathymetry and advanced navigational software for piloting. The major objectives of this paper are, first, to summarise recent dynamics in the e-Navigation field, and second, to present a practical implementation of the e-Navigation concept in the Vistula Lagoon area.

Sign in / Sign up

Export Citation Format

Share Document