The German instrument pool. for amphibian seismology (DEPAS)

Transcription

1 The German instrument pool for amphibian seismology (DEPAS) Mechita Schmidt-Aursch Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research Bremerhaven OBSIP 2013 OBS Workshop Redondo Beach, CA October 21-22, 2013

2 Introduction DEPAS: Deutscher Gerätepool für amphibische Seismologie (German instrument pool for amphibian seismology): Founded in the year 2005 as so-called Large scale facility for German researchers 100 onshore seismometer are operated by the Helmholtz Centre Potsdam, German Research Centre for Geosciences (GFZ) 80 ocean bottom seismometer are managed by the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research Bremerhaven (AWI) (GFZ/AWI/Wikipedia)

3 Introduction How to make amphibian seismology as simple as possible? Technical aspects: Identical equipment of onshore stations Identical equipment of offshore stations Comparable parameters of all stations Short-term or long-term use possible (AWI) User support: (GFZ) Simple application procedure Assistance in OBS cruise planning Complete service package Contract technician for OBS cruises

4 Onshore stations Geophone: Güralp CMG-3ESP Compact, 60 sec - 50 Hz Digital data recording unit: EarthData PR6-24, 24 bit, Hz, 40 GB hard disk Solar panels, adaptor cabels, transport boxes Onshore station assembled in the laboratory without outdoor casing (GFZ)

5 Ocean bottom seismometer Floating unit: syntactical foam; frame and pressure tubes: titanium alloy Max. deployment depth: 6000 m (standard OBS), 7300 m (deep-going OBS) Max. deployment time: 18 months (standard OBS), 8 months (deep-going OBS) Fully mounted OBS ready for deployment, weight: approx. 405 kg (incl. anchor) (K. Fischer)

6 Ocean-bottom seismometer Geophone, gimbal-mounted: Güralp CMG-40T, 60 sec - 50 Hz / 120 sec 50 Hz Hydrophone: HighTechInc HTI-04-PCA/ULF, 100 sec - 8 khz Digital data recording unit: Send Geolon MCS, 20 GB hard disk / 32 GB flash card Deployment of OBS in horizontal position, velocity of descent: approx. 0.5 m/s (AWI)

7 Ocean-bottom seismometer Acoustic release transponder: Kum K/MT 562 and Kum K/MT 8011M onboard unit VHF radio beacon: Novatec RF-700A1 and Seimac DR500 bearing receiver Xenon flashlight: Novatec ST-400A OBS after emerging at the sea surface, rising velocity: approx. 1.2 m/s (AWI)

8 Application DEPAS-marine (80 OBS) Scientist AWI Bremerhaven DEPAS-onshore (100 STN) GFZ Potsdam??? Field experiment All scientists from German institutions can apply for the use of onshore and/or ocean-bottom instruments. Scientists from foreign institutions need a German cooperation partner acting as applicant.

9 Application DEPAS-marine (80 OBS) Scientist AWI Bremerhaven DEPAS-onshore (100 STN) GFZ Potsdam Online application form External steering committee External steering committee AWI internal advisory board GFZ internal advisory board Field experiment The online applications will be handled by an external steering committee and an internal advisory board. Combined application of onshore and offshore instruments is possible.

10 Summary of OBS projects 25 completed projects around the world so far, three ongoing measurements Deepest OBS deployment: Tonga Trench, more than 7000 m water depth Largest active experiment: Nares Strait, 35 OBS, 91 (loss-free!) deployments Largest passive experiment: Reunion Hotspot, 48 German + 9 French OBS

11 European perspective European OBS Pools: Ten pools in six countries (DE, FR, ES, GB, PT, IT) Two new pools under construction (Denmark, Poland) Approx. 400 OBS altogether (W. Crawford) > 200 wide- or broadband > 140 one year or more operating time Various technical standards (AWI) Various procedures for application, data management, etc. (G. Mangano) (AWI) (W. Crawford) (W. Crawford)

12 European perspective Committee for the Harmonization of European OBS Parks (CHEOPS): Improvement/standardization of instruments and processing/archiving techniques enhancement of data quality and integration with onshore data Promotion of interoperability between OBS pools and cross-european experiments grand challenge questions, capacity for rapid response Foster collaboration with industry and policy institutions greater economic, societal and scientific impact Next generation of European instruments improvement of data quality simplified processing development of specialized OBS (e.g. rapid response, real-time comm., disposable, air-deployable...) (

13 Further Information WorldWideWeb: