Ocean bottom seismographs GNS for active and passive seismic observation for the depth range from 0 to 7000 meters

Transcription

1 Ocean bottom seismographs GNS for active and passive seismic observation for the depth range from 0 to 7000 meters

2 Self popup Ocean bottom seismic recorders key operational features Ø Low energy consumption no down time for re-charging (or replacement) of batteries during survey. Ø Continuous autonomous recording time up to 90 days.. Ø Wireless fast download (up to 15Mb/sec) of recorded data after surfacing of instruments copying of recorded data during re-location of seabed nodes to the new sea floor position. Ø Wireless control of seabed nodes operations (switching on/off, testing, setting of acquisition parameters). Ø Automatic measurement of clock drift/ GPS clock synchronization through the radio transparent housing. Ø Deployment and retrieval of instruments from the sea floor is provided using sea water as a delivery agent. Ø Eco-friendly anchor dissolves in water after the survey and segregates into natural ingredients

3 Instruments and Technical Characteristics The pool of 65 second generation (2014) GNS seismic stations has been built

4 General Characteristics of GNS Seismic Seabed Nodes Deep-water radio transparent instrument case Seismic recorder Glass sphere of 33 cm diameter inlaying robust plastic shell 4 channels 24 bits ADC for each channel, 125 db at 0 db amplification, 153 db is full range Dynamic Range User interface / data backup link Wireless USB. OS Windows client program for device management User terminal Tablet, Laptop or Desktop PC Seismic sensors 3 orthogonal 4,5 Hz gimbals mounted geophones, one deep water hydrophone Release command Acoustic call or automatically by preset time Ballast anchor release Electrochemical with mechanical support (salt waters) or solenoid type (any waters) Ballast anchor environmental feature Self-dissolving into natural sea components after surveying (12 kg weight in air) Continuous recording time Up to 90 days (lithium batteries) Detecting equipment on the sea Radio beacon with GPS coordinates surface transmission, flash light (at night), flag Weight 20 kg in air (without anchor) Depth range 0 to 7000m

5 GNS node performance capacity Multiple times seabed deployment/recovery without opening or recharging node Automatic clock synchronization with GPS signals through the instrument case. Build in GPS receiver, activated automatically after surfacing node from a seabed. Wireless on/off power switch. No needs to open node case after transport and seabed recovery, all preparation and tests before deployment could be done on vessel deck Wireless user interface. Fast data downloading after node retrieval to a ship deck Automatic and manual tests of power supply, seismic recorder and acoustic release

6 GNS OBS project experience Year Region Type of Work Scope of Work Client 2011 Gulf of Perevoznaya, Barents Sea, Russia 2D reflection seismic survey in transit zone with high tidal and muddy seafloor 40 km of 2D reflection seismic, data processing LUKOIL, NarianMar Geophysics 2012 The Laccadive Sea, Indian Ocean, water depths 200 to 2500m 2D Wide Angle Reflection/ Refraction, imaging of sub basalt sediments, Earth crust investigation 820 km, 420 deployments every 2 km ONGC, India 2014 The Black Sea, Kerch Straight, water depths 5 to 15m Passive seismic investigations, seismic hazard assessment at Kerch Straight Area 1 0 n o d e s deployments for 60 days of continuous recording Institute of the Physics of The Earth Russian Academy of Science, JSC Giprotransmost 2014 The Black Sea, Gelendzhik area, water depths 10 to 20 m Designing and testing of seabed broadband seismological cable real-time recording station 3 deployments + cable station comparative test L L C M a r i n e Innovations, Institute of Oceanology 2015 Indian Ocean, water depth 4500m Deep seismic sounding, investigation of the Earth crust, velocity model building 420 km line, 12 deployments every 20km NCAOR, India

7 Survey areas and field operations in India 2012, 2D/ 820 km for ONGC 2015, 2D/420 km for NCAOR

8 2D project in transit ultra-shallow tidal zone of the Barents Sea

9 Designing, development and testing of wide-band sea bottom station with cable link transmitting real-time data

10 Passive seismic monitoring in the Black Sea; data example for cable station and OBS Local earthquake in the Black Sea area (occurred on 01/09/2014 at 00:27:24, 5 UTC) recorded by sea-bottom station and three nodes (OBS1-3). Horizontal scale is in seconds

11 2. Создание и тестирование широкополосной донной станции на кабеле передающей данные в реальном времени. Август 2014

12 Study of seismic hazard in the Kerch Strait area: Deployment of network of 10 OBS for 2 months for continuous monitoring of local seismicity Seismological array location ( area of 30 by 30 km). One time deployment for 62 days of continuous observation

13 Bibliography D.A. Ilinski, A.Y. Razumov, A.A. Korneev, A.M. Rusalin, I.A. Gots. Innovative approach and mobile technology of seismic surveying in tidal flats а hard-to-reach Arctic areas //Seismic Equipment V. 49, No. 2, pp D.G. Levchenko, L.I. Lobkovskiy, D.A. Ilinski, I.B. Raushenbach, V.V. Ledenev, K.A. Roginskiy. Study case of development and field testing of multifunctional cable sea bottom seismic recorder // Seismic Equipment V. 50, No.4, pp Manoj Kumar Bhartee and Karad Kapil. Wide Angle Reflection-Refraction profiling (WARRP): An effective tool for subsalt exploration A case study//10 th Biennial International Conference & Exposition. Kochin. 2013/ P 138, pp D.A. Ilinski, Chirkov E.B.//Innovation in exploration technologies for Russian shelf // RAO/CIS OFFSHORE 2011 PROCEEDINGS. pp S-Petersburg, Chimizdat с Internet site

14 Seismic survey OBS servicing & cooperation proposal Our OBS applications: Combined with marine seismic multi-streamer 3D surveys in the areas with restrictions for seismic vessel operations (oil-production platforms, shallow zones (with depth less than 20m), and in the critical areas with the most complicated geology for minimization of drilling risks. 2D and 3D operations in transit zones and shallow and ultra-shallow waters 2D deep-water operations for superior imaging of sub-basalt and sub-salt structures, gas chimney and sea-floor seeps UNCLOS 2D surveys, regional and scientific deep waters surveys Areal passive seismic sea bottom observations, direct search for hydrocarbons We offer: Pool of 65 OBS for active and passive seismic surveying Organizing the shooting vessel for OBS survey Setup the seismic source on your vessel for OBS survey Development and implementation of innovative sea bottom recording equipment and seismic sources.