In memory of DVW President Prof. Dr. Ing. Karl-Friedrich Thöne

Since the »Declaration of Bremen« (»Bremer Erklärung«) from 2008 the geo societies DVW (German Society for Geodesy, Geoinformation and Land Management) and DHyG (German Hydrographic Society) are friendly connected. On 15 July 2016 the President of the DVW Prof. Dr. Ing. Karl-Friedrich Thöne died unexpectedly at the age of 59 years. At a deeply moving sea burial off the island of Föhr we said farewell.

• Ausgabe: HN 105 Seite: 62
• DOI: 10.23784/HN105-14
• Autor/en: Hagen Graeff

The liberated organisation

The IHO has been working on organisational changes for several years. During the 3rd Extraordinary International Hydrographic Conference (EIHC) in 2005 and the International Hydrographic Conference (IHC) in 2007, the constitutional documents were approved in the meeting but they needed support by 48 member countries. As this now has been reached, changes will be made, entering into force on 8 November 2016.

• Ausgabe: HN 105 Seite: 60–61
• DOI: 10.23784/HN105-13
• Autor/en: Mathias Jonas

A new view on the Elbe – Dynamic and interactive 3D views for public information purposes in news media

In collaboration with the German newspaper WELT , a team of researchers from Hafen-City University Hamburg developed new views of the River Elbe, showing the riverbed in a couple of 3D interactive views and videos. These have been integrated into a multimedia special which follows the goal to give people better insights into the complex topic of the fairway adjustment of the Elbe. This contribution describes input data as well as its processing and visualisation.

DTM visualisation | dynamic views | interactive 3D views | public participation

• Ausgabe: HN 105 Seite: 56–58
• DOI: 10.23784/HN105-12
• Autor/en: Tanja Dufek, Johannes Kröger, Brendon Duncan, Jochen Schiewe

Burial depth determination of cables using acoustics – Requirements, issues and strategies

Depth-of-burial (DOB) surveys are well-known in the oil and gas business to obtain the exact position and burial depth of pipelines or cables after dredging and for regular maintenance. With expanding offshore wind farming in the wake of the »Energiewende« site explorations, route and cable DOB surveys become increasingly important in this industry, too. Various geophysical methods like magnetic, electro-magnetic and acoustic sensors are used to detect and track buried cables. For best detection probability of buried cables to date mostly lines crossing the expected cable route are surveyed. Although this is suited to detect the cable and get its position with high accuracy, survey companies require more efficient technologies, accounting for both, operational and processing costs. Thus they are looking for easy to operate equipment that follows the cable along its actual route, works at different water depths, weather and seabed conditions and gives immediate and reliable results to produce deliverables with high accuracy of XYZ cable positions.

detection of buried objects | acoustic cable tracking | depth of burial – DOB | sub-bottom profiler – SBP

• Ausgabe: HN 105 Seite: 50–54
• DOI: 10.23784/HN105-11
• Autor/en: Jens Wunderlich, Jan Arvid Ingulfsen, Sabine Müller

The challenge of choosing the right method for surveying power cables

The rising number of wind parks, and thus the demand for new survey tasks, results in continuous development for companies working in the renewable energy sector. Building a wind park requires laying inter-array and export cables. Those cables are buried or covered to protect them, bringing environmental changes to a minimum. A common depth of burial ranges from 1.5 m to 3 m. The challenge of surveying those buried power cables is choosing the right method.

cable tracking | depth of burial | HVAC/HVDC | survey power cables

• Ausgabe: HN 105 Seite: 47–49
• DOI: 10.23784/HN105-10
• Autor/en: Oliver Anders