SEAFLOOR OBSERVATORIES (eBook)

A New Vision of the Earth from the Abyss

Paolo Favali, Laura Beranzoli, Angelo De Santis (Autoren)

eBook Download: PDF

2015 | 2015
XXXI, 676 Seiten
Springer Berlin (Verlag)
978-3-642-11374-1 (ISBN)

Infos

The oceans cover 70% of the terrestrial surface, and exert a pervasive influence on the Earth's environment but their nature is poorly recognized. Knowing the ocean's role deeply and understanding the complex, physical, biological, chemical and geological systems operating within it represent a major challenge to scientists today. Seafloor observatories offer scientists new opportunites to study multiple, interrelated natural phenomena over time scales ranging from seconds to decades, from episodic to global and long-term processes.

Seafloor Observatories poses the important and apparently simple question, 'How can continuous and reliable monitoring at the seafloor by means of Seafloor Observatories extend exploration and improve knowledge of our planet?' The book leads the reader through:

• the present scientific challenges to be addressed with seafloor observatories
• the technical solutions for their architecture
• an excursus on worldwide ongoing projects and programmes
• some relevant scientific multidisciplinary results
• and
• a presentation of new and interesting long-term perspectives for the coming years.

Current results will yield significant improvements and exert a strong impact not only on our present knowledge of our planet but also on human evolution.

Inhalt

Contents 6
List of figures 18
List of tables 30
1 Introduction 33
Part I Present scientific challenges to be addressed using seafloor observatories 35
2 Integrating continuous observatory data from the coast to the abyss: Assembling a multidisciplinary view of the ocean in four dimensions 36
2.1 Introduction 36
2.2 Spatial (environmental) scope 37
2.3 Temporal scope 38
2.4 Catastrophic episodicity 39
2.5 Complex interconnectedness 40
2.6 Challenges of multidisciplinarity 40
2.7 Integrated networks 40
2.8 Scientific initiatives 41
2.9 Scientific development 42
2.9.1 Builders 42
2.9.2 Future builders 43
2.9.3 Bridge-builders 44
2.9.4 Data analysts 46
2.9.5 Knowledge beneficiaries 47
2.10 Participants and data access 48
2.11 Summary 49
References 49
3 Underwater neutrino telescopes: Detectors for astro-particle physics and a gateway for deep-sea laboratories 53
3.1 Introduction 53
3.2 High-energy neutrino astronomy 55
3.3 High-energy neutrino detection 58
3.3.1 The Cherenkov detection technique in transparent natural media 59
3.3.2 Underwater Cherenkov neutrino telescopes 61
3.4 Towards a deep-sea infrastructure for neutrino astronomy and Earth and sea science in the Mediterranean Sea 63
3.4.1 NESTOR: Neutrino Extended Submarine Telescope with Oceanographic Research 65
3.4.2 ANTARES: Astronomy with a Neutrino Telescope and Abyss environmental RESearch 66
3.4.3 NEMO: NEutrino Mediterranean Observatory 67
3.4.4 KM3NeT 69
3.4.4.1 Optical modules 70
3.4.4.2 Detection unit mechanical structure 71
3.4.4.3 Readout technology 73
3.4.4.4 Sea-floor network 74
3.5 Beyond the km3: New techniques for ultra-high-energy neutrino detection 74
3.6 Deep-sea science with neutrino telescopes 75
3.6.1 Bioluminescence 76
3.6.2 Seawater optical properties 77
3.6.3 Biofouling and sedimentation 79
3.6.4 Underwater currents 79
3.6.5 Bioacoustics 80
3.6.6 Geophysics 81
3.7 Conclusions 82
References 82
Web resources 87
4 Seafloor observations and observatory activities in the Sea of Marmara 88
4.1 Introduction 88
4.2 Geohazards in the Sea of Marmara 90
4.2.1 The Sea of Marmara seismic gap 90
4.2.2 Submarine landslides 91
4.2.3 Tsunamis 91
4.3 Fluids and seismicity in the Sea of Marmara 92
4.4 Oceanographic and environmental sensitivity of the Sea of Marmara 94
4.5 Sensors for seafloor observations in the Sea of Marmara 94
4.5.1 Seismic motion 94
4.5.2 Flowmeters 94
4.5.3 Piezometers (pore-pressure sensors) 95
4.5.4 Gas-bubble monitoring 95
4.5.5 Methane sensor 97
4.5.6 Oceanographic sensors 98
4.6 Recommended observatory sites 99
4.7 Present initiatives for seafloor observatories in the Sea of Marmara 100
4.7.1 Marmara Sea Bottom Observatory (MSBO) project 100
4.7.2 The ESONET Marmara-Demonstration Mission project 100
4.8 Conclusions 102
References 102
5 The Hellenic deep sea observatory: Science objectives and implementation 109
5.1 Introduction 109
5.2 Hellenic observatory: Science objectives 111
5.2.1 Geodynamics and seismicity 111
5.2.2 Seafloor instabilities 112
5.2.3 Tsunamis 114
5.2.4 Fluid flow and mud volcanism 115
5.2.5 Thermohaline circulation and climate change 116
5.3 Existing stand-alone observatory (Poseidon system – Pylos site) 117
5.3.1 Surface buoy: Air-sea interaction monitoring 117
5.3.2 Water column monitoring 118
5.3.3 Seabed platform 119
5.4 Ongoing operation management 119
5.4.1 Data flow, management and quality control procedures 119
5.4.2 Data and information product dissemination 121
5.4.3 Operation of the POSEIDON-Pylos observatory, 2007-2010 122
5.5 Concluding remarks 125
Acknowledgments 127
References 127
6 Marine seismogenic-tsunamigenic prone areas: The Gulf of Cadiz 132
6.1 Introduction 132
6.2 Large earthquakes and tsunamis in the Gulf of Cadiz 135
6.3 Main hazard source zones in SW Iberia 137
6.3.1 Gloria Fault 137
6.3.2 SW Iberian transpressive domain 137
6.3.2.1 Gorringe Bank zone 139
6.3.2.2 Horseshoe Marques-de-Pombal zone 139
6.3.2.3 The Algarve Margin 140
6.3.2.4 East dipping subduction slab 141
6.4 The strategy for seafloor continuous monitoring 142
6.4.1 First results 143
6.5 Conclusions 146
Acknowledgments 146
References 147
Part II Technical solutions for seafloor observatory architecture 153
7 The role of Information Communication Technologies (ICT) for seafloor observatories: Acquisition, archival, analysis, interoperability 154
7.1 Introduction 154
7.2 Different types of ocean observatories 155
7.3 Benefits of ICT for an ocean observatory 155
7.4 Mandate of a software infrastructure for ocean observatories 157
7.5 Observatory system design 157
7.5.1 Design decisions imposed on the ICT 158
7.5.2 Network design considerations 159
7.5.3 National security issues 159
7.5.4 General network security threats mitigation 160
7.5.5 Design choices 161
7.5.6 Private network and IP address range 161
7.5.7 Access only through VPN or through software proxies 162
7.5.8 Isolation of VLANs to isolate instrument categories from one another 162
7.5.9 User authentication and authorization 163
7.5.10 Timing and time signals 163
7.6 Data acquisition 164
7.6.1 Data types in ocean sciences 165
7.6.1.1 Data flow as streams – Data flow as an event management problem 165
7.6.1.2 Interfaces to many different types of instruments 166
7.6.1.3 Interoperability 167
7.6.1.4 Science data vs. engineering data 167
7.6.2 Data archive and distribution management 168
7.6.2.1 The cost of a 25-year mandate 168
7.6.3 Data repository growth: Constant, linear or exponential? 170
7.6.3.1 Types of products 170
7.6.3.2 Evolution of raw data rate 171
7.6.3.3 Adapting the storage structure to expected use 172
7.6.3.4 Observatory assets management and operation support 173
7.6.3.5 Data access and analysis 174
7.6.3.6 Remote use of underwater assets 176
7.7 Summary 176
7.8 Non-exhaustive list of ocean observatories 178
Reference 178
Glossary of acronyms 178
8 Long-term subsea observatories: Comparison of architectures and solutions for infrastructure design, interfaces, materials, sensor protection and deployment operations 180
8.1 Introduction 180
8.2 Comparison between observatory architectures 181
8.2.1 Vertically cabled architecture 181
8.2.2 Non-cabled architecture 181
8.2.3 Cabled architecture 183
8.2.3.1 Architecture and mechanical design of a node and a junction box 184
Mechanical design overview 187
SJB design solutions 187
8.3 Recommendations for signals, protocols and connector pin-out between infrastructure and instrumentation 189
8.4 Long-term deployment: Materials for subsea observatories 192
8.5 Long-term deployment: Biofouling protection for marine environmental devices and sensors 193
8.5.1 Biofouling protection by “controlled” biocide generation: Localized seawater electro-chlorination system 195
8.6 ROV operations: Deployment and maintenance operations 197
8.7 Conclusion and next steps 198
Acknowledgments 199
References 199
Web resources 201
Glossary 201
9 Development and demonstration of a mobile response observatory prototype for subsea environmental monitoring: The case of ROSE 203
9.1 Introduction 203
9.2 System specifications 204
9.2.1 Functional specifications 204
9.2.2 Technical specifications 206
9.2.2.1 Acoustic network 206
9.2.2.2 Radio-electric link 207
9.2.2.3 Information flows 208
9.2.2.4 Sea bottom stations 209
9.2.2.5 The buoy 211
9.2.2.6 On-shore control station 211
9.2.2.7 Messengers 212
9.3 Study and construction of a prototype system 213
9.3.1 Seafloor stations 213
9.3.2 Buoy 217
9.3.3 Sensors 217
9.4 Prototype tests in Ifremer seawater tank 218
9.4.1 Station tests 219
9.4.2 Messenger tests 219
9.5 Demonstration at sea 220
9.5.1 Sea operations 221
9.5.1.1 System deployment 221
9.5.1.2 System operation from mid-June to early September 221
9.5.1.3 System recovery 222
9.5.2 Analyses of at-sea demonstration results 222
9.5.2.1 Communication system and station operation 222
9.5.2.2 Biofouling 226
9.5.2.3 Messenger 226
9.5.2.4 Sensors 227
9.6 Conclusions 230
List of abbreviations 232
Acknowledgment 232
References 232
10 Construction of the DONET real-time seafloor observatory for earthquakes and tsunami monitoring 234
10.1 Introduction 234
10.2 System overview 236
10.3 Backbone cable system 237
10.4 Science node 238
10.5 Observatory 240
10.6 Scenario 242
10.7 ROV for observatory construction 243
10.8 DONET construction 248
10.9 Summary 249
Acknowledgment 250
References 250
11 GEOSTAR-class observatories 1995-2012: A technical overview 252
11.1 Introduction 252
11.2 The origins: ABEL and DESIBEL 253
11.3 GEOSTAR 255
11.3.1 GEOSTAR mission 1 (Adriatic Sea) 269
11.3.2 GEOSTAR mission 2 (Southern Tyrrhenian Sea) 270
11.3.3 GEOSTAR missions 3 and 4 (Southern Tyrrhenian Sea) 273
11.3.4 GEOSTAR mission 5 (Gulf of Cadiz) 277
11.3.5 GEOSTAR mission 6 (Gulf of Cadiz) 280
11.4 SN1 284
11.4.1 SN1 mission 1 (Ionian Sea) 286
11.4.2 SN1 mission 2 (Ionian Sea) 288
11.4.3 SN1 mission 3 (Ionian Sea) 291
11.5 MABEL (SN2) 294
11.5.1 MABEL (SN2) mission 1 (Weddell Sea, Antarctica) 298
11.6 SN3 298
11.6.1 SN3 missions 1 and 2 (Southern Tyrrhenian Sea) 303
11.7 SN4 304
11.7.1 SN4 mission 1 (Corinth Gulf) 306
11.7.2 SN4 missions 2 and 3 (Marmara Sea) 309
11.8 GMM 312
11.8.1 GMM missions 1 and 2 (Gulf of Patras) 313
11.8.2 GMM mission 3 (Ionian Sea) 318
11.9 Conclusions 319
Acknowledgments 321
References 321
Part III World-wide recent and ongoing projects and programmes 328
12 The two seafloor geomagnetic observatories operating in the western Pacific 329
12.1 Introduction 329
12.2 Instrumentation at sea 331
12.3 Seafloor experiments 333
12.3.1 Observed time-series on the seafloor 337
12.4 The geomagnetic secular variation contained in the time series 339
12.5 Discussion 341
12.6 Conclusions 342
Acknowledgments 342
References 342
13 The DELOS project: Development of a long-term observatory in an oil field environment in the Tropical Atlantic Ocean 346
13.1 Introduction 346
13.1.1 Science and oil industry collaboration 347
13.1.2 Rational 348
13.2 System description 348
13.2.1 Seafloor docking stations 349
13.2.1.1 Glass fiber material testing 350
13.2.1.2 Structure analysis and modelling 350
13.2.1.3 Foundation design 352
13.2.1.4 Hydrodynamic modelling 353
13.2.1.5 Observatory modules 356
13.2.1.6 Camera module 356
Close view camera 356
Wide view camera 357
13.2.1.7 Oceanographic module 358
13.2.1.8 Acoustic module 358
Passive sonar 359
Active sonar 359
13.2.1.9 Sediment trap module 360
13.2.1.10 Guest module 360
13.2.1.11 ROV module 360
13.2.1.12 Battery packs 361
13.3 Installation 361
13.4 Periodic service 362
13.5 Results 362
13.6 Discussion 363
References 363
14 Sub-sea environmental observatory integrated with the KM3NeT neutrino telescope infrastructure in the Mediterranean Sea 366
14.1 Introduction 366
14.1.1 Neutrino astronomy 367
14.2 Scientific case for a cabled infrastructure in the Mediterranean Sea 368
14.3 KM3NeT conceptual design 369
14.3.1 Site criteria 371
14.3.2 Water optical properties 372
14.3.2.1 Light transmission 372
14.3.2.2 Optical background 372
14.3.2.2.1 Potassium 40 372
14.3.2.2.2 Bioluminescence 372
14.3.2.3 Deep-sea currents 374
14.3.2.4 Sedimentation 375
14.3.2.5 Biofouling 376
14.3.2.6 Distance offshore 377
14.3.3 Scientific opportunities in the Mediterranean Sea 377
14.3.3.1 Physical oceanography 379
14.4 Infrastructure management and operation 381
14.4.1 Neutrino telescope operations 381
14.4.2 Marine science observatory operations 381
14.4.3 Safety requirements 382
14.4.4 Data management and access 383
14.4.5 Public relations and outreach program management 383
14.4.6 Users and stakeholders 383
14.5 Marine observatory integration in the Mediterranean 384
Acknowledgments 385
References 385
15 ANTARES neutrino telescope and deep-sea observatory 389
15.1 Introduction 389
15.2 Science objectives 390
15.3 Technical description of neutrino telescope and observatory 390
15.3.1 Stages in construction of the detector 390
15.3.2 Design of the neutrino telescope 393
15.3.3 Instrumentation line 396
15.3.3.1 ADCP 398
15.3.3.2 CTD 399
15.3.3.3 Sound velocimeter 400
15.3.3.4 Water transmission 400
15.3.3.5 Oxygen monitor 401
15.3.3.6 Camera 401
15.3.3.7 Oceanographic instruments on neutrino telescope lines 403
15.3.3.8 Mounting of instruments on lines 403
15.3.4 Other instruments in a deep-sea observatory 403
15.3.4.1 Deep-IODA 403
15.3.4.2 Seismometer 406
15.3.5 Acoustic positioning system 407
15.3.6 Acoustic detection system 410
15.3.6.1 System description 410
15.3.6.2 Acoustic sensors 412
15.3.6.3 Offshore electronics and acoustic data acquisition 412
15.3.6.4 Onshore data processing 413
15.3.6.5 Ambient noise measurements 413
15.3.6.6 Position reconstruction of sources 414
15.4 Sample data from ANTARES detector 415
15.4.1 Data available from the neutrino telescope lines 415
15.4.2 Data available from the environment instrumentation in the system 419
15.4.2.1 Sea water current 420
15.4.2.2 Oceanographic processes in the deep western Mediterranean Sea 420
15.4.2.3 Internal waves in the deep western Mediterranean Sea 422
15.4.2.4 Temperature 423
15.4.2.5 Oxygen dynamics in the deep waters 424
15.4.2.6 Pressure sensor 425
15.4.2.7 BioCamera 426
15.4.2.8 Sound velocity 428
15.5 Extensions for Marine and Earth science 428
15.5.1 Secondary junction box (SJB) system 428
15.5.2 KM3NeT 432
15.6 Summary 433
References 433
16 NEPTUNE Canada: Installation and initial operation of the world’s first regional cabled ocean observatory 435
16.1 Introduction 435
16.2 History of NEPTUNE Canada 436
16.2.1 Concept design and funding phase 437
16.2.2 Infrastructure design, testing and installation phase 440
16.2.3 Instrument design, testing and installation phase 444
16.3 Data management and archiving 448
16.4 Challenges for NEPTUNE Canada 450
16.5 Future opportunities for NEPTUNE Canada 454
16.6 Socio-economic benefits of NEPTUNE Canada 454
16.7 Summary and invitation 455
Acknowledgments 457
References 457
17 The ALOHA cabled observatory 459
17.1 Introduction 459
17.2 Background 460
17.3 Infrastructure 463
17.3.1 Shore station and cable 464
17.3.2 Junction box 464
17.3.3 Power system 465
17.3.4 Observatory module 467
17.3.5 Other system aspects 468
17.4 Research 468
17.4.1 Research with core measurements 469
17.4.2 Examples of future research directions 476
17.5 Concluding remarks and epilogue 478
Acknowledgments 480
References 481
18 Next-generation science in the ocean basins: Expanding the oceanographer’s toolbox utilizing submarine electro-optical sensor networks 484
18.1 A grand challenge 484
18.2 Ocean complexity – natural laboratories 487
18.2.1 Development of the US undersea cabled observatory 492
18.2.2 Regional scale nodes 493
18.2.3 Regional scale nodes science, instruments and moorings 497
18.2.3.1 Ocean processes in the NE Pacific, the regional scale nodes and endurance array 498
18.2.3.2 Cascadia subduction earthquakes, methane hydrates and seeps, novel organisms 500
18.2.3.3 Linkages among submarine volcanoes, hydrothermal venting, and life in extreme environments: Axial Seamount 505
18.3 Cabled observatories and amplification with emerging technologies 509
18.4 Broader potential – cabled human presence in the sea 514
18.5 Global problems require international solutions 514
Acknowledgments 515
References 515
19 Technical preparation and prototype development for long-term cabled seafloor observatories in Chinese marginal seas 522
19.1 Introduction 522
19.2 System design of cabled seafloor observatories 524
19.2.1 Power system 525
19.2.2 Communication system 526
19.2.3 Topology consideration 527
19.3 Prototype development for cabled seafloor observatories 528
19.3.1 Undersea station 528
19.3.2 Junction box 530
19.3.3 Submarine cable 531
19.3.4 Shore station 532
19.3.5 Reliability engineering 533
19.4 In-situ scientific instrumentation 534
19.4.1 Scientific Instrument Interface Module (SIIM) 534
19.4.2 Chemical Parameter Analyzing System (CPAS) 535
19.4.3 Hydrodynamic Environment Monitoring System (HEMS) 538
19.5 East China Sea trials 540
19.6 MARS sea trials 540
19.7 Concluding remarks 543
Acknowledgments 544
References 544
20 From ESONET multidisciplinary scientific community to EMSO novel European research infrastructure for ocean observation 549
20.1 Introduction 550
20.2 ESONET and EMSO: Synergic framework 552
20.3 Major ESONET-NoE activities and achievements 553
20.3.1 Demonstration missions and test experiments 553
20.3.1.1 AOEM: Arctic Ocean ESONET Mission: A step towards understanding a key area for climate studies 554
20.3.1.2 LOOME: Long-term observations on mud-volcano eruptions in the Norwegian margin 555
20.3.1.3 MODOO: MOdular Deep Ocean Observatory: The sustained monitoring of the Porcupine Abyssal Plain for studying biogeochemi 555
20.3.1.4 MoMAR-D: MOnitoring the Mid-Atlantic Ridge Lucky Strike vent field (off Azores) 556
20.3.1.5 LIDO: LIstening to the Deep-Ocean environment with a regional network of multidisciplinary seafloor observatories 557
20.3.1.6 MARMARA-DM: Looking for a relationship between gas seepage and seismicity in the Marmara Sea (Istanbul Supersite) 558
20.3.1.7 Ligurian Sea: Biochemical process of the water column and slope instability monitoring 559
20.3.2 Underwater operation and best practices 559
20.4 Sustained European-scale ocean observations through EMSO infrastructure 561
20.4.1 Present status of the EMSO nodes 563
20.4.1.1 Arctic 563
20.4.1.2 Porcupine Abyssal Plain (PAP) 564
20.4.1.3 Azores Islands 564
20.4.1.4 Canary Archipelago PLOCAN 565
20.4.1.5 Ligurian Sea 566
20.4.1.6 Western Ionian Sea 566
20.4.1.7 Hellenic Arc 567
20.4.1.8 Marmara Sea 568
20.4.1.9 Black Sea 568
20.4.2 EMSO data infrastructure 569
20.4.2.1 Data management principles 570
20.4.2.2 Interoperability of observatory metadata and sensors 573
20.5 Conclusions and perspectives 574
Acknowledgments 576
References 576
Websites 579
Part IV Relevant scientific results with a multidisciplinary emphasis 582
21 Seafloor observatory for monitoring hydrologic and geological phenomena associated with seismogenic subduction zones 583
21.1 Introduction 583
21.2 Geophysical and geological settings at the ACORK stations 585
21.3 Freshening observed at the décollement 589
21.4 Methane hydrate in accretionary prism 590
21.5 Formation pressure observations 592
21.6 Discussion 593
21.7 Summary 595
Acknowledgments 595
References 595
22 Modeling of regional geomagnetic field based on ground observation network including seafloor geomagnetic observatories 600
22.1 Introduction 600
22.2 Potential theory 602
22.3 Spherical cap harmonics – 2D case 604
22.4 Regional geomagnetic reference field – A case study 606
22.4.1 Data 606
22.4.2 Synthetic inversion 607
22.4.3 The regional geomagnetic reference field over the Western Pacific 609
22.5 Discussion 610
22.6 Conclusions 611
Acknowledgments 612
References 612
23 Seafloor borehole observatories in the Northwestern Pacific 615
23.1 Introduction 615
23.2 Seafloor borehole geophysical observatories 617
23.3 Geophysical records and results from the seafloor borehole observatories 622
23.3.1 Geodetic records 622
23.3.2 Seismological records 622
23.3.3 Earth structure from the deep-sea borehole observatories 629
23.4 Seafloor cabled observatories 631
23.5 Conclusions 632
Acknowledgments 632
References 632
24 A first insight into the Marsili volcanic seamount (Tyrrhenian Sea, Italy): Results from ORION-GEOSTAR3 experiment 637
24.1 Introduction 637
24.2 Geological setting 638
24.3 The ORION experiment 640
24.4 Data analysis 643
24.4.1 Seismometer and gravimeter data 643
24.4.2 Magnetic data 650
24.5 Conclusions 651
Acknowledgments 652
References 652
25 Development and application of an advanced ocean floor network system for megathrust earthquakes and tsunamis 656
25.1 Introduction 656
25.2 Previous research 660
25.3 Configuration of DONET 662
25.4 Expected results 665
25.5 Summary and future plans 672
Acknowledgments 673
References 673
26 Concluding Remarks: Perspectives and longterm vision 676
26.1 Vision 676
26.2 Visionaries and progress 677
26.3 Challenges 677
26.4 Public safety 678
26.5 Paradigm shift 678
26.6 Historical significance 678
Acknowledgments 680
List of the referees in alphabetical order 680
Index 683

Produkt-Details

• Erscheint lt. Verlag: 5.5.2015
• Reihe/Serie: Geophysical Sciences
• Reihe/Serie: Springer Praxis Books
• Zusatzinfo: XXXI, 676 p. 348 illus., 306 illus. in color.
• Verlagsort: Berlin
• Sprache: englisch
• Themenwelt: Naturwissenschaften ► Biologie
• Themenwelt: Naturwissenschaften ► Geowissenschaften ► Geografie / Kartografie
• Themenwelt: Naturwissenschaften ► Physik / Astronomie
• Themenwelt: Technik
• Schlagworte: Abyss • Biophysical interaction • natural phenomena • Seafloor instabilities • Sea floor oberservatories
• ISBN-10: 3-642-11374-5 / 3642113745
• ISBN-13: 978-3-642-11374-1 / 9783642113741