Common Dataset Information

Transcription

1 Common Dataset Information Introduction The Common Dataset is a defining feature of the Shallow Survey conferences and consists of a series of surveys conducted over a common area of seabed using a variety of systems. It provides equipment manufacturers the opportunity to showcase their latest systems. It also gives hydrographic researchers and scientists a chance to test their latest algorithms on the dataset so that rigorous comparisons can be made and reported. Some examples of the systems that could be trialled are Multibeam, Phase Measurement Sonar, Synthetic Aperture Sonar, Sub Bottom Seismic, Airborne Photographic, LiDAR and physical sampling Common Dataset The Common Dataset for Shallow Survey 2012 will be collected in Wellington Harbour between May 2010 and April The harbour and surrounding coastal area has a number of well-defined features, including the wrecks South Seas and Wellington, an armoured seawall constructed of Tetrapods and Akmons along the southern boundary of the airport, aquifers, wharves and marinas. The seabed inside the harbour basin is largely fine-grained sediment, with gravel and reefs around the coast. The area outside the harbour on the southern coast is an active environment, with moving sand and exposed reefs. A marine reserve is also in this area. The dataset will be provided by June This will allow time for the data to be processed and analysed, and papers presented on the results. 1 Common Dataset Overview

2 Areas of interest Sub-surface faulting Freshwater Seeps South Seas wreck Wharves & port infrastructure Sediment types Sea defence structures HMNZS Wellington wreck Habitat Taputeranga Marine Reserve Habitat 2

3 Survey Areas All manufacturers are requested to complete at least Area 1 and ideally Area 2. These allow a direct comparison between all systems and are detailed below. Survey objectives: Achieve at least IHO SP-44 Ed 5 Special Order depth accuracy and feature detection and Survey coverage: 800x800 metres. Manufacturers can also collect data in other Areas, as indicated below. Each manufacturer is to submit the following deliverables by 30 June 2011: the raw data in manufacturer s own format which may include calibrated backscatter, bathymetry, side scan, snippets and raw beam data the component datasets, ie. sound velocity profiles and tides a short factual report detailing the survey and data collected Survey line logs for multibeam systems - non-cleansed XYZ data for each beam, but with sound velocity and tides applied, in Generic Sensor Format (GSF) cleansed XYZ data for each beam. Observed tidal data from the Wellington tide gauge, located at Queens Wharf, will be provided. Compulsory Area 1 HMNZS South Seas ( S, E) In 1942, the minesweeper HMNZS South Seas collided with the Inter-island steamer Wahine and sank north-east of Point Halswell in water depths of 22m. 3

4 Compulsory Area 2 HMNZS Wellington ( S, E) Located in approximately 16m of water just off the south coast, the HMNZS Wellington was sunk in 2005 as a dive site. Being exposed to strong southerlies, the wreck has broken into three distinct sections, with a minimum depth of 6.1m recorded in Multibeam survey was undertaken by National Institute of Water and Atmospheric Research (NIWA) prior to the sinking but no surveys have been undertaken since. NOTE: The wreck is in a marine reserve and therefore the seabed cannot be disturbed and no samples can be collected. 4

5 Optional Areas Area 3: Habitat/Marine Reserve Areas that give the best opportunities to show habitat mapping capabilities are Wellington's Taputeranga Marine Reserve on the south coast, and the area around Barrett Reef. Both areas are challenging as they are exposed to the swell of Cook Strait. NOTE: Within the marine reserve the seabed cannot be disturbed and no samples can be collected. The survey should be limited to water depths greater than 5m in the area bounded by the following WGS84 co-ordinates: S, E S, E S, E S, E Area 4: Wharves and port infrastructure Within the inner harbour are several types of man-made structures: pylon-supported wharves for tankers at Seaview, the Overseas Terminal building, land reclamation along the Hutt Motorway and the container terminal, and the seawall at the southern end of the runway of the Wellington International Airport. Area 5: Sediment features The area on the east side of the harbour entrance, south of Mākaro/Ward Island, provides a good test for mapping seafloor sediment features. Here, veneers of finer grained sediment overlay beds of gravels and rock outcrop. Another area for sediment features is the seabed on the western side of the harbour entrance. Area 6: Fresh water seeps The seafloor just south of the mouth of the Hutt River at the northern end of the harbour is characterised by numerous fresh water seeps sourced from the Hutt River aquiver. The river mouth also provides an opportunity to show system capabilities in extremely shallow waters of 0 5m. Area 7: Sub-surface faulting The Wellington Fault, a major topographic feature of Wellington's landscape, has only a very limited trace on the seafloor, but has been shown on high resolution seismic data collected in the late 1980s (Lewis, 1989). This provides an excellent opportunity to show the advance in shallow seismic system capabilities. Ref: K. B. Lewis (1989): New Zealand Journal of Geology and Geophysics, 1989, Vol. 32:

6 NIWA Vessel Management For the purpose of acquiring data for the Common Dataset, NIWA will make its coastal research vessel Ikatere and crew available. The following will be provided as standard: Fugro SeaSTAR 8200 HP (VPS mode) WADGPS positioning receiver. POS MV 320 motion sensor. Stern-mounted A-frame. An RTK positioning network may be provided, if required. The lever arms of equipment mounting positions have been surveyed. A NIWA marine survey technician will be present during mobilisation. Additional equipment is to be organised by the manufacturer. Bookings can be made between May 2010 and April 2011, however availability will be subject to NIWA s work programme. Ikatere is also fitted with: a retractable moonpool arrangement to enable transducers to be retracted for fast transit. The overall measurement of the moonpool is 760x610mm. forward acoustic transducer compartment Davit mount for supporting over the side mounts. Further details are outlined below. 14m coastal research catamaran Ikatere Coastal research launch Ikatere designed specifically for seabed sampling, oceanographic research and hydrographic surveying. Length : 13.9 m Beam : 4.85 m Draft : 0.70 m Gross tonnage : 14.9 tonnes Construction : Aluminium alloy catamaran Power : Twin Cummins QSC rated at 500HP Propulsion : 322 Hamilton Waterjets Helm Power Generation A-Frame : Hamilton Blue Arrow : DC/AC Inverter/Charger 4.0 kva output Onan AC Diesel Generator set 11ka : Stern mounted. Lifting capacity 500kgs. Deck clearance 3m width between frame 2.5m. Detailed specifications of Ikatere are attached. NIWA will provide the vessel Ikatere based on the following: NZ$6,400 + GST for up to four days, which includes vessel and crew with technician support during mobilisation. NZ$1,600 + GST for each additional day. Rates include mobilisation, survey operations and demobilisation. A maximum of three manufacturer s personnel to be carried at any one time. The NIWA Standard Marine Services Agreement terms and conditions will apply. 6

7 NIWA can also provide the following, if required: logistical support by accepting shipments of equipment an office space a technician and engineering support. If manufacturers wish to take the opportunity to demonstrate equipment to potential clients during their Common Dataset acquisition time, NIWA commercial rates will apply and be advised on application. If manufacturers wish to demonstrate their systems during the Shallow Survey 2012 conference, please contact NIWA with your requirements. Contact details For information on bookings, timing and availability, or further enquiries, please contact Neville Ching, National Institute of Water and Atmospheric Research Ltd (NIWA), 301 Evans Bay Parade, Greta Point, Private Bag , Kilbirnie, Wellington, New Zealand. n.ching@niwa.co.nz Phone: , Fax: Mob: Alternatively, please contact Stuart Caie, Land Information New Zealand (LINZ), 160 Lambton Quay, Private Box 5501, Wellington scaie@linz.govt.nz 7