| id |
652 |
| mdfileid_nerc_guid |
c5a7ef2f-f8c4-066c-e044-0003ba9b0d98
|
| abstract |
Wessex Archaeology (WA) was commissioned by English Heritage (EH) to undertake geophysical surveys as part of the project entitled ‘Wrecks on the Seabed: Assessing, Evaluating and Recording’, supported by Round 2 of the Aggregate Levy Sustainability Fund (ALSF). The specific aim of this project was to provide industry, regulators and contractors with guidance on the archaeological assessment, evaluation and recording of wreck sites. ‘Assessment, evaluation and recording’ are taken to include various methods of archaeological investigation that are intended to improve the understanding, preservation and appreciation of the historic environment. Geophysical surveys were conducted over four wreck site areas. This archive relates to the geophysical survey over Hastings Shingle Bank covering the area of the wreck Thomas Lawrence. During the geophysics survey sidescan sonar, single beam echosounder, multibeam echosounder and magnetometer data were acquired. Sidescan sonar, magnetometer and single beam bathymetric surveys were conducted over the Hastings Shingle Bank by Titan Surveys Ltd., aboard the survey vessel Titan Explorer, under supervision from WA staff. These surveys was conducted intermittently during 15 survey days over 47 days between the 17th February – 5th April 2005 with substantial delays due to adverse weather conditions. The geology and geophysics component of the data are archived at British Geological Survey (BGS) MEDIN Data Archive Centre (DAC) for Geology and Geophysics. Data were also provided to other archive centres as appropriate.
|
| confidentiality |
unclassified (open file)
|
| cruise_data_url |
None
|
| cruise |
WESSEX2A
|
| additional_info |
The navigation and data acquisition system used aboard the Titan Explorer was based on Trimble’s HYDROpro software. The primary and secondary positioning systems, echosounder, magnetometer and heading sensor were interfaced to this system. In addition, position data, analogue fix marks and digital fix information were output to the sidescan sonar, magnetometer and echosounder systems. Single beam bathymetric data was acquired using an Odom Hydrotrac echosounder and a CMS-25 motion reference unit on all sidescan sonar and magnetometer survey lines conducted over the 2km x 2km area. Bathymetric data were recorded digitally by HYDROpro, and reduced to Chart Datum using post-processed kinematic (PPK) observed tides. A Klein 3000 dual frequency digital sidescan sonar, which operates at both 125kHz and 445kHz simultaneously, was used for all sidescan surveys. Magnetometer data over the Hastings Shingle Bank area were collected using a Geometrics G881 Caesium Magnetometer. Multibeam echosounder data were acquired from the vessel Wessex Explorer between the 15th and 19th August 2005. Navigation was provided by a Fugro Omnistar 8300 HP GPS receiver, with corrections provided via satellite subscription service which gave a positional accuracy of ±10cm. Multibeam bathymetric data was acquired by Netsurvey Ltd. using a Reson 8125 Multibeam echosounder and a MHARS motion reference unit and gyro. Sound velocity profiles were recorded at the start of each multibeam survey and then as required during the survey. The raw bathymetric data were processed Netsurvey Ltd, in order to apply tidal corrections and remove any spikes in the data.
|
| end_date |
2005-02-17 00:00:00
|
| cruise_alias |
None
|
| nav_equip_type |
Differential GPS
|
| restitle |
Geophysical Survey: WESSEX2A: (17/Feb/2005 to 17/Feb/2005)
|
| geophys_equip_type |
Echo Sounder, Magnetometer, Multibeam, Sidescan Sonar
|
| accessuse_restric |
unrestricted use, copyright acknowledgement
|
| ship |
Titan Explorer
|
| samp_equip_type |
None
|
| client |
Wessex Archaeology
|
| start_date |
2005-02-17 00:00:00
|
| start_date_est |
Real
|
| terms_of_use |
Available under the Open Government Licence subject to the following acknowledgement accompanying the reproduced Wessex Archaeology materials "Contains Wessex Archaeology materials ©Wessex Archaeology [year]"
|
| contractor |
Titan Environmental Surveys Ltd
|
| terms_of_use_url |
http://nationalarchives.gov.uk/doc/open-government-licence/version/3/
|
| cruise_area |
CP2 Regional Sea Boundaries: Eastern Channel, Offshore 1:250k: Dungeness-Boulogne, SeaVoX Sub-Ocean: DOVER STRAIT
|
| end_date_est |
Real
|
