Seismic Survey

Seismic surveys are carried out in the United Kingdom Continental Shelf (UKCS) in the search for, and managing of, oil and gas reserves. Modern large-scale surveys are conducted using a towed array of 'airguns' – cylinders of compressed air. The array, typically containing tens of such cylinders, is discharged simultaneously, to generate a pressure pulse which travels downwards into the seabed. The extent to which seismic disturbance from airguns affects cetaceans is not well known for all species due to the limited research carried out to date. Seismic surveys at sea do not necessarily constitute a threat to marine mammals, JNCC consider that providing the JNCC seismic guidelines for minimising the risk of disturbance and injury (June 2009) are implemented it will minimise the risk of causing injury to marine mammals.

Under the EU Habitats Directive 92/43/EEC Article 12 – member states are required to establish a system of strict protection for the animal species listed in Annex IV which include all cetaceans. The Offshore Petroleum Activities (Conservation of Habitats) Regulations 2001 implements the EU Habitats Directive for all oil and gas activities within the UKCS. As part of these regulations any company wishing to carry out a seismic survey must apply for consent from the Department of Energy and Climate Change (DECC, formerly the DTI) the JNCC are consulted on whether consent should be granted for each individual seismic survey and if a consent is granted, a standard condition is that the JNCC guidelines for minimising the risk of disturbance and injury to marine mammals from seismic surveys (August 2010) are always followed. The guidelines advise on using marine mammal observers whom conduct watches for marine mammals during the pre-shooting search and advise the crew on the implementation on the guidelines. MMOs receive formal training in their role through attendance on a JNCC approved Marine Mammal Observer Courses.

The 2009 JNCC seismic guidelines recommend the use of a redesigned Marine Mammal Recording Form, these were developed under a project funded by the E&P Sound and Marine Life Joint Industry Programme (JIP) , it is hoped that these forms will become a standard reporting form that can be used across the globe. The marine mammal recording form is an Excel spreadsheet and has embedded worksheets named: Cover Page, Operations, Effort and Sightings. A word document named ‘Deckforms’ is available, and MMOs may prefer to use this when observing before transferring the details to the Excel Spreadsheets. A guide to completing the forms is also provided below. 

After the survey is complete a report, ‘the MMO report’, is submitted to the JNCC for each individual survey detailing how the JNCC Guidelines were implemented and the completed marine mammal recording forms, and any problems or instances of non-compliance with the guidelines detailed.

The data from these forms is analysed by the JNCC and a series of reports have been produced entitled 'Marine Mammal Observations during seismic surveys for the years 1996 to 2002.

The ability to determine range is a key skill for the MMOs to have, and a useful tool to perform this function is a range finding stick. Instructions on how to design and use a range finding stick are provided below. 

For a copy of the DECC regulations please visit the DECC website at: http://www.og.decc.gov.uk/