UNRAVELLING THE COMPLEXITIES SCIENCE PLAN FOR 2014-2019 SCIENCE PLAN FOR 2014-2019 - GFZ-Potsdam
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INTERNATIONAL
CONTINENTAL SCIENTIFIC
DRILLING PROGRAM
UNRAVELLING
OF PLANET EARTH THE WORKINGS OF
UNRAVELLING THE COMPLEXITIES
PLANET
SCIENCE EARTH
PLAN FOR 2014–2019
SCIENCE PLAN FOR 2014–2019
We invite you to think about why Earth Science
matters, and the often surprising ways in which it
affects our lives.
UNRAVELLING THE WORKINGS OF PLANET EARTH SCIENCE PLAN FOR 2014–2019 edited by Horsfield, B., Knebel, C., Ludden, J. and Hyndman, R.
4 EXECUTIVE SUMMARY
ICDP
EXECUTIVE SUMMARY
Earth science goals The programme
Modern earth science has two basic ICDP boasts a strong and active partici- Through the unique
goals: seeking to unravel the histori- pation of twenty-two member nations. capacities of scientific
cal archives that are locked up in rocks It has undertaken more than 30 drilling
drilling to provide
formed over the entire history of the projects and run 75 workshops. Its cur-
Earth, and understanding the structure rent budget of $3.5 million a year is a
exact, fundamental,
and dynamics of the active planet on small fraction of that of the Internation- and globally significant
which we live. To realise both goals sci- al Ocean Discovery Program ( IODP ) or knowledge of the
entific drilling is essential: it uncovers other large earth science infrastructure composition, structure,
rock archives containing the records of projects. ICDP—already lean and mean
and processes of the
tectonic, climatic and biological cycles, with a minimum of bureaucracy—is
and impacts from extraterrestrial bod- making important ongoing changes to
Earth’s crust.
ies, from the present day, back into its operations to build an even stronger
deep time. Targeted scientific drilling technical base and reshaping its man-
allows us to sample, measure and moni- agement structure to be more effective.
tor the Earth to help develop sustain- Networking with other major earth sci-
able resources. Drillhole observatories ence programmes is being strengthened,
give key insights into Earth’s internal and bridges with the private and gov-
dynamic activities, such as fluctuations ernment sector built, thus strengthening
in heat and the magnetic fields or earth- ICDP’s economic and societal portfolio.
quakes and volcanoes.
The spectrum
It would be impossible to undertake ICDP has a broad portfolio centred on
modern earth science research with- scientific drilling. Firstly, it provides a
out scientific drilling. The International strategy for successful science deliv-
Continental Scientific Drilling Program ery by funding workshops, leading and
( ICDP ) has played a primary role over supporting technological innovation,
the past two decades, uncovering geo- conducting outreach and teaching pro-
logical secrets from beneath the conti- grammes and actively cooperating with
nents. It has enabled first-class science programmes such as IODP. It provides
to be pursued, numerous targets to be co-funding for coring as well as exper-
probed and hypotheses to be tested, tise and advice on all matters technical
with the result that fundamental dis- and logistical. It offers technological
coveries about ‘System Earth’ have been support for geophysical logging and data
made, often bringing important socio- management. ICDP is able to mobilise
economic benefits. multiple drilling platforms in diverse
5 EXECUTIVE SUMMARY
ICDP
environments: from lake sediment drill- understanding spatial and temporal
ing for records of climate change over variability, and the interconnectivity of
the past thousands of years, to special systems. This is an organisational chal-
technology for drilling into high-tem- lenge facing all drilling organisations.
perature hydrothermal systems and
micro-sampling for fluids using steri- The science plan
lised drill-core sampling systems. Public This document, the third ICDP Science
outreach and teaching are strong com- Plan, came about by engaging the inter-
ponents of ICDP's profile, and is being national science community around the We cordially invite you
expanded further. ICDP is making theme of ‘Unravelling the workings of to read this White Paper.
significant difference in educating the Planet Earth’. It lays out some of the big
You will discover why
public about our subsurface, providing questions that confront the earth sci-
confidence that we know enough about ences and suggests ways to answer them
earth science matters,
the upper kilometres in order to provide that can be achieved by scientific drill- and uncover the many
resilient solutions to infrastructure and ing. Some of these questions are funda- surprising ways in
resource development. A strong edu- mental, for instance, the origin of life which it affects your
cation programme will inspire young on Earth, whereas others use the past
everyday life.
people and help create the next genera- history of the Earth to imagine what a
tion of scientists who will be needed to future Earth might look like. Some drill-
specialise in geology, geophysics, geo ing applications are highly specialised,
chemistry and geomicrobiology. such as that for developing sensor net-
works in underground observatories to
Process scales monitor earthquakes and volcanoes, the
Scientific drilling must deal with the latter underpinning geothermal energy
Earth's fundamental processes that production. To varying extents, these
work on timescales from microseconds, scientific programmes have objectives
exemplified by stress transfer during that are shared with the energy, water,
a fault rupturing, to hundreds of mil- insurance, mining and other industries,
lions of years for plate tectonic cycles. and with many government objectives,
The same is true of length, breadth and but ICDP is firmly directed as a research
depth, from sub-micron bio-films and enabler focused on cutting edge science
mineral defects, to thousands of kilo- questions and innovations.
metres in fault movements, basin-filling The main themes in this document are:
and mountain-building processes. The • active faults and earthquakes
interconnectivity of processes, including • heat and mass transfer
feedbacks, amplifications and degrees • global cycles, and
of organisation between them, is stag- • the hidden biosphere
geringly complex, involving chemical, • cataclysmic events
physical and biological components. These will underpin societal challenges in:
Scientific drilling has made many fun- • water quality and availability
damental discoveries with individu- • climate and ecosystem evolution
al drill holes, but the coordination of • energy and mineral resources and
targeted activities is a key element in • natural hazards.
7 CONTENTS ICDP EXECUTIVE SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 ICDP—WHO WE ARE AND WHAT WE DO . . . . . . . . . . . . . . . . . . . . . . . . . . 8 QUO VADIS, ICDP ? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 CONFERENCE ACKNOWLEDGEMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 CHALLENGES FOR SCIENCE AND SOCIETY . . . . . . . . . . . . . . . . . . . . . . . 12 SCIENTIFIC DRILLING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 MORE THAN SIMPLY DRILLING HOLES—A STRATEGY FOR SUCCESS 16 PREAMBLE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 PAVING THE WAY FORWARD—THE SCIENCE PLAN ACTIVE FAULTS AND EARTHQUAKES . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 GLOBAL CYCLES AND ENVIRONMENTAL CHANGE . . . . . . . . . . . . . . . 32 HEAT AND MASS TRANSFER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 THE UBIQUITOUS HIDDEN BIOSPHERE . . . . . . . . . . . . . . . . . . . . . . . . . . 56 CATACLYSMIC EVENTS —IMPACT CRATERS AND PROCESSES . . . . . . 66 LINKS WITH OTHER ORGANISATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . 74 ROLE OF INDUSTRY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78 EDUCATION AND OUTREACH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80 EPILOGUE—ICDP IN ACTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
8 ICDP—WHO WE ARE AND WHAT WE DO
ICDP
ICDP —WHO WE ARE AND WHAT WE DO
Figure 1. ICDP’s commingled funding principle.
Our mission the drilling programme itself, and not
ICDP is the international platform for for the scientific investigations that fol-
scientific research drilling in continents. low. Commingled funding is the name
Founded in 1996 at GFZ in Potsdam, of the game—we encourage and assist
Germany, its mission is to explore the the scientists in gathering funding, but
Earth’s subsurface so that its structure do not take on full financial sponsor-
and workings are unfolded. ship. A key element provided by ICDP
in addition to financial support, is oper-
What we provide ational support—the sharing of tech-
ICDP is an infrastructure for scientific nical and logistical know-how and the
drilling. It provides financial and logis- provision of operational personnel and
tical assistance for leading international equipment is critical to scientific drill-
teams of earth scientists to investigate ing organisations. ICDP is an enabler,
sites of global geological significance. committed to putting excellent scientific
The financial assistance on offer is for ideas into best practice.
9 ICDP—WHO WE ARE AND WHAT WE DO
ICDP
The base The science plan
ICDP brings together scientists and ICDP is not a science funding body but
funding agencies from 22 nations will try to lay out the key research chal-
and one international organisation lenges in the coming years by commis-
( UNESCO ) to work together at the sioning a science plan. This plan acts as a
highest scientific and technical level to roadmap for the international earth sci-
collectively grant funding and imple- ence community and at the same time
ment logistical support. More than 30 serves as a docking station for national
drilling projects and 75 planning work- funding initiatives. This White Paper,
shops have been supported to date. ‘Unravelling the workings of Planet
The programme has an average annual Earth’, is a strategy document laying
budget of $3.5 million from member- out the major scientific challenges that
ship contributions. may be addressed by continental scien-
tific drilling for the period 2014-2019.
Benefits It is the third for ICDP: the first was
What are the benefits of the programme published shortly after the foundation of
for its international sponsors? To secure the program in 1996 by M. D. Zoback Figure 2. ICDP at the COSC drill site, Sweden.
ICDP funding, all projects must fulfil and R. Emmermann, entitled ‘Inter-
rigorous selection criteria, one of which national Continental Scientific Drill-
is addressing modern societal challeng- ing Program’ and in 2007 the second
es, be it the protection against natural ‘Continental Scientific Drilling, A dec-
disasters (‘natural hazards’), unravelling ade of Progress, and Challenges for the
past climate change ( ‘climate and eco- Future’ by U. Harms, C. Koeberl and
systems’ ), or serving an ever-growing M. D. Zoback. In parallel to the cur-
population with natural resources ( ‘sus- rent science plan is a special issue of the
tainable georesources’ ). ICDP projects International Journal of Earth Sciences
always have this element of added value. that provides a snapshot of the scien-
tific investigations currently underway
that are directly tied with drilling inves-
tigations.
10 QUO VADIS, ICDP ?
ICDP
QUO VADIS, ICDP ?
Figure 3. On-site participants, ICDP Science Conference 2013
The ICDP science conference ‘Imag- The conference’s aim was to debate
ing the Past to Imagine our Future’, the way forward for ICDP over the
was convened in Potsdam, Germany, next five years. The science plan
11–14 November, 2013. One hundred took shape by dovetailing scientific
and sixty-four invited attendees from goals with societal (socio-economic)
29 countries took part on-site—from challenges. The conference was also
early career dynamos to acknowledged used to strengthen and expand ties
experts—representing the full palette among member countries, consider
of earth science disciplines, with many how to best incorporate industry inter-
more participating via live streaming ests into ICDP (a science-driven organ-
from the geoscience world at large. isation). There also is the objective to
instigate new measuress for a better
gender balance in its panels and com-
mittees.11 CONFERENCE ACKNOWLEDGEMENTS
ICDP
CONFERENCE ACKNOWLEDGEMENTS
Our sincere thanks go out to those who White Paper contributions
have contributed their valuable time, Nicholas Arndt,
boundless energy and creative ideas to Keir Becker,
the conference and the White Paper. Marco Bohnhoff,
Achim Brauer,
Presenters, discussion leaders Philippe Claeys,
Flavio Anselmetti, Andrew Cohen,
Jean-Philipp Avouac, Georg Dresen,
Keir Becker, William Ellsworth,
Marco Bohnhoff, Guðmundur Ómar Friðleifsson, Figure 4. Scientists debating at the poster session.
Eduardo de Mulder, Ulrich Harms,
Donald Dingwell, Brian Horsfield,
William Ellsworth, Hans-Wofgang Hubberten,
Guðmundur Ómar Friðleifsson, Ernst Huenges,
Ulrich Harms, Roy Hyndman,
Steve Hickman, Jens Kallmeyer,
Brian Horsfield, Tom Kieft,
Roy Hyndman, Carola Knebel,
Jens Kallmeyer, Christian Koeberl,
Tom Kieft, Achim Kopf,
Christian Koeberl, Ilmo Kukkonen,
Ilmo Kukkonen, Ralf Littke,
Steve Larter, John Ludden,
Ralf Littke, Volker Lüders,
John Ludden, Stefan Luthi,
Stefan Luthi, Jim Mori,
Jim Mori, Karsten Pedersen,
John Shervais, Bernhard Prevedel,
Lynn Soreghan, Judith Schicks,
Jim Russell, Lynn Soreghan,
Alexander van Geen, Joanna Thomas,
Jim Whitcomb, Robert Trumbull,
Thomas Wiersberg Jim Whitcomb,
Thomas Wiersberg,
Maarten de Wit12 CHALLENGES FOR SCIENCE AND SOCIETY
ICDP
CHALLENGES FOR SCIENCE AND SOCIETY
Integrating the needs of science and Cycles
society is a cornerstone of the new sci- Then there is climate change … We All in all, the workings
ence plan … need to distinguish the change inflict- of planet Earth are
ed by man, for instance by combusting
far from understood;
The challenge fossil fuels, from the natural cycles that
Preparation for and minimising the risk are part and parcel of Mother Earth.
a great many frontiers
of natural disasters, supplying an ever Records of what has gone before in await modern-day
growing world population with indus- Earth history are preserved in sedimen- explorers. Scientific
trial raw materials, energy, clean water, tary rocks at surprisingly high resolu- drilling provides
and addressing the threats posed by glo- tion, that help to unravel the puzzle.
key insights into all of
bal change; these are some of the fun-
damental challenges facing mankind in The origins of life itself and the evolu-
these processes.
the 21st century. All of these challenges tion of species lie preserved in the sed-
are inextricably linked with the work- imentary record awaiting discovery.
ings of planet Earth, namely the chemical Unravelling the links among human
reactions, physical movements and bio- habitat, climate and palaeogeography is
logical interactions taking place within already underway.
the solid Earth and at interfaces with the
hydrosphere, atmosphere and biosphere. The deep biosphere
When we think of life on present-day
Warning and preparation Earth, we think of the diversity that is
Events such as earthquakes dramati- displayed in rain forests and oceans, and
cally impinge upon our lives in seconds, in the types of micro-organisms (want-
minutes and hours, but the root cause ed and unwanted) which live in and
is a build-up of stress over thousands amongst us. Intriguingly, there also is a
of years deep within the crust, often at biosphere within the pores and cracks of
distant locations. Predicting exactly rocks (recognised so far to about 2 km)
where and when such natural hazards that is roughly the same size as the bio-
will occur is a daunting task, but key sphere we know and love. We are only
advances have already been made by just beginning to understand how this
monitoring the stress and strain and deep biosphere is involved in the natural
fluid flow in the Earth’s subsurface using cycling of elements, and exploring the
sensitive instrumentation, and by issu- ways in which we can understand and
ing early warnings via integrated earth put this underground system to good
science infrastructure. use.THE EARTH BENEATH OUR FEET—
THE DARK UNDERGROUND
Brian Horsfield GFZ— German Research Centre for Geosciences, Germany
We think we know our planet, the underworld and to verify our models ‘We want to bring
Earth. Detailed maps, aerial pictures of Earth is to recover samples from scientific drilling on
and satellite images give us the im- depths and to obtain data in the dyna
continents within
pression —albeit false —that no place mic downs.
on our planet remains unexplored.
the reach of every
But who knows what it is like within Drilling is an expensive proposition member of the earth
the earth beneath our feet and how that rarely a single country can afford science community.’
can we gain information about this? due to the enormous costs associated
with the logistics. How can researchers
Geologists study every road cut, justify such costs to a funding agency,
where machines and dynamite have if the results are merely scientific and
exposed the layers of rock normally do not gush out a wealth of resources?
hidden beneath soil and vegetation. This is exactly where ICDP comes
Geophysicists use seismic rays and in. The goal of this programme is to
electromagnetic waves to figuratively encourage earth scientists considering
peel away the layers of the earth. drilling as a tool for their research
Geochemists study the rocks which and to make drilling the reality check
they believe were once part of the for the models and ideas developed.
interior of the earth. But the plethora
of information gathered by all these The scientific focus of ICDP for the
means leads at best to models and forthcoming years is laid out in this
hypotheses about the Earth’s interior. White Paper to serve as a guideline for
The best way to enlighten the obscure continental scientific drilling.
Figure 5. 3 D structural model of the Central European Basin System.14 SCIENTIFIC DRILLING ICDP SCIENTIFIC DRILLING Figure 6. The build-up of stress. Scientific drilling is an indispensa- ICDP is not alone in conducting sci- ble and unique tool for exploring and entific drilling on a global scale. We are unraveling the myriad natural and building stronger links between the ter- anthropogenic processes that are part restrial ( ICDP ) and marine ( IODP ) and parcel of ‘System Earth’. The pre- realms for the development of con- cious relicts and living systems it con- certed actions, extending from involve- tains need to be probed, collected, mon- ment in respective science plan defini- itored and analysed at key sites around tion, through individual project design, the globe. to the joint publication of the magazine
15 SCIENTIFIC DRILLING ICDP Scientific Drilling. There are further links with ANDRILL, whose focus is the Antarctic, and the Deep Carbon Observatory, which studies the deep carbon cycle, are also under develop- ment. The pooling and coordinating of our respective actions, whether it be on land, sea or ice, is impera- tive. The White Paper revisits these issues. Scientific drilling has objectives that are broadly shared with the oil and Figure 7. Drill bits at the Alpine Fault drill site, New Zealand gas, water, insurance, mining and oth- er industries. All are seeking to better understand the workings of ‘System Earth’. In the commercial world the objectives are to secure new resources, exploit known ones, and minimise risk associated with natural hazards and resource development. Scientific drill- ing remains science-driven, seeking to understand the chemistry, physics and biology in time-space coordinates. It makes sense to explore areas of com- mon interest with industry, for exam- ple selected data and sample acquisi- tion. When managed astutely, pure and applied research go hand in hand to achieve common objectives. The White Paper considers these issues.
16 MORE THAN SIMPLY DRILLING HOLES—A STRATEGY FOR SUCCESS ICDP MORE THAN SIMPLY DRILLING HOLES —A STRATEGY FOR SUCCESS Scientific drilling relies heavily on lead- • Provide operational support for ing edge technology. But it is way more drilling activities, downhole logging than that. The ICDP portfolio covers tools, and sample- and data- finances, logistics and operational sup- management software systems. port, and all with minimal administra- • To ensure appropriate monitoring tive and bureaucratic fuss. Here is a of the programme and accountability list of tasks and challenges that are part to sponsors in terms of scientific and parcel of that portfolio: effectiveness and financial efficiency; • Identify world class drilling • Ensure effective application sites to probe geological targets and dissemination of the results. Also of global significance. to inspire young scientists. ICDP • Fund workshops to assemble the best makes substantial effort to encourage science teams, define scientific earth science education and facilitate objectives and mesh scientific ideas knowledge transfer. with practical drilling concepts. • Provide accountability for sponsors We are striving to improve upon the for the programme as a whole, way we do business by ensuring that in terms of scientific effectiveness each task is conducted efficiently and and financial efficiency. effectively. The closing chapter of • Arrange commingled funding this White Paper looks into how the concepts for the effective planning, organisation can be managed better. implementation and execution of a viable strategic programme which meets scientific objectives of socio-economic relevance. • Identify sites for international cooperation in scientific drilling, and thus to provide cost effective means of answering key scientific questions, in close collaboration with other scientific drilling organisations. • Ensure that appropriate pre-site surveys are carried out at an early stage in planning, including required permits, environmental and local social issues.
17 ICDP
Modern technology for scientific drilling:
the basic elements
Geophysical pre-site surveys are needed to map out the lay
of the land. This means accurate target definition as well as
avoiding potential drilling hazards such as unstable rock
formations.
Blowout preventers are used to control the fluid and gas
pressure inside the well. They consist of several valves to
close the well if overpressure occurs.
Steel casing, cemented into place, is used to seal the
borehole along its length. Large diameters are used at
shallow depths, and succeeded by casing of progressively
lower diameter at depth. That way unstable zones can be
stabilised and different fluid horizons can be isolated
(e.g. groundwater from salt water).
Active control systems behind the bit help to ensure
exact vertical drilling. Thereby friction between the drill
string and the borehole wall can be minimised and the
borehole wall stays stable.
The drilling mud serves many purposes. It discharges
cuttings from the bit to the surface and stabilises the bore-
hole. It also constantly cools the drill bit, reduces friction, Cement
drives the downhole motor, and balances differences in
pressure. The drilling mud must therefore be monitored and
its chemistry and rheology adjusted continuously.
Borehole measurements and tests help to characterise
rocks and, fluids, thereby maximising safety. ICDP projects address a whole host of geologi-
cal targets from deep to shallow, from tectoni-
cally simple to complex, and under very diffe-
rent pressure and temperature conditions.
Controlled drilled horizontal wells with up to 10 km of
deviation and multiple re-entry protocols allow access to
Modern technology ensures all these targets
distant formations. When drilled along the bedding of a can be reached, even if they lie at 12 km depth!
formation, gas and crude oil production efficiency is
enhanced. Having said that, costs rise exponentially with
depth and degrees of difficulty, so detailed and
careful planning is prerequisite.
Figure 8. Drilling scheme18 THE SCIENCE PLAN—PREAMBLE
ICDP
THE SCIENCE PLAN — PREAMBLE
Maarten de Wit Africa Earth Observatory Network, Nelson Mandela Metropolitan University, Port Elizabeth, South Africa
Earth processes proceed at variable of Earth and life systems: the connectiv- Unearthing palaeo-
speeds, from steady and slow, to fast, ity between black smokers and ecosys- complexity through con-
sometimes showing gradual change, tems; or that of global changes emerg-
tinental scientific drilling
sometimes sudden, and sometimes ing out of the atmospheric ‘symphony’
impinging catastrophically on ecosys- of fluctuating palaeotemperatures and
for the benefit of
tems. In rock systems these changes palaeo-gas concentrations, as recorded future generations.
are recorded as stratigraphical inter- in ice cores. These, and similar discov-
ference patterns that geoscientists con- eries forced a relatively rapid shift in
vert with ever-greater precision into a focus from closed-system solid-Earth
narrative full of complexity and sur- geodynamics to its symgeosis with the
prises. We do not fully comprehend external gas–fluid envelope, the exo-
the system (Ager, 1973; Rudwick, 2005; sphere. The solid Earth’s ‘leaky’ systems,
Blackburn et al., 2013), but progress each evolve whilst interacting with each
has been made: geoscience has self- other, recycling through non-linear,
organised into earth systems science positive and negative, slow and fast,
enabling more complex questions to be feedback reactions forced by seemingly
addressed about systemic interdepend- unpredictable fluctuations in energy
encies and connectivity of palaeo-proc- and mass exchange. But, this ubiquitous
esses; about how oceans that opened connectivity is poorly understood.
and closed affected palaeo-global cur-
rents, climates, weathering, seawater Complex systems are comprised of
chemistry, and biodiversity. And when many interactive parts with the abil-
it became clear that such hyperconnec- ity to generate a new quality of collec-
tivity is vulnerable to failure through tive behaviour through self-organisa-
rapid external forces, such as extrater- tion (Prigogine, 1984; Odem, 1988; Bak,
restrial impacts or large mantle plumes, 1996; Camazine et al., 2001; Ben-Jacobs,
earth systems science suddenly stumbled 2002). Petrologists have long docu-
into a new era of exploring Earth as a mented evolving patterns and phase
complex interactive adaptive system. changes (solid–liquid–gas as a function
of pressure, temperature and composi-
Fundamental insights into how the tion) in mineral and rock systems at the
Earth functions as a complex auto- edge of chaos (fluids). At such special
catalytic and adaptive system emerged phase boundaries self-organisation is
at the end of the 20th and early in spontaneously constituted, and further
the 21st century, following exciting evi- complexity evolves through dissipative
dence, for example, of the co-evolution processes. Scale-invariant earth systems19 THE SCIENCE PLAN—PREAMBLE
ICDP
Figure 9. Complexity word cloud
somehow all appear to acquire the abil- maintains homeostasis through cause
ity to hover between order and cha- and effect (Lovelock, 1972). Which sys-
os. Ongoing ICDP projects which are tem dominates the Earth is still open to
looking into the supercritical zones of debate, but can be tested with new high-
hydrothermal and magmatic complexes resolution data and disruptive thinking.
are already providing new and needy
observational data to test for conditions Increasingly, ecosystem studies have
of instability at mantle scales. Similarly, generated concepts that may apply to
fast response drilling into fault zones all complex systems when appropriately
can test for critical states in the crust. generalised with network models, ener-
gy, and information. High-fidelity strati-
Self-organisation in natural systems graphical studies may recognise such
emerges from a dynamic hierarchy of signals in geosystems too. The ICDP
information. Self-organisation of earth community and their IODP colleagues
systems reconnects its parts and proc- have unique opportunities to core dis-
esses into new operating cycles through parate archives that overlap in time and
evolving information between core, space to search for palaeo-connectivity
mantle, crust, air, oceans, and life. No between earth systems, to reconstruct a
model can yet account holistically for palaeo-interconnected world, and tease-
such dynamic connectivity within natu- out local and global adaptive behaviour
ral information systems (Toniazzo et al., of the past. Bringing together the obser-
2005). Some argue that the basis for this vations from time-overlapping cores
is simply rooted in the second law of ther- retrieved from lakes, ice, speleothems,
modynamics to maximise entropy pro- rocks and minerals, will lead to better
duction unbeholding to cause and effect. understanding of palaeo-adaptive sys-
Systems dissipate and reorganise, driven tems over deep time and add immense
by simultaneous interactivity far from value to drilling projects.
equilibrium (Kleidon and Lorenz, 2005).
Others entertain the view that the entire The ability to compare overlapping
planet is a self-organising system that sequences across the planet, at selected20 THE SCIENCE PLAN—PREAMBLE
ICDP
8 44 26
37
3 26
43 26 31 7 54 23
14 14 24
12
10
42 18 35 49 23 2
17
39 33 46
32 22 17 51 57
27 20 33 13
43 9 36 30 4 45 58 3 34
15 28 52
25
27
18
49 28 48
31
3
37 40 9 29 66 5
6 34 10 12 19
23 35
42 4 10 11 19 8 16 27 24
56 46 50 16 47
38 20 7 21
14
28 9 17 63 11
4 32
7 55 24 25 3
47
8 44 30
5 3 29 65
21
16
62
2 15 5
36 21 64
48
41 39 1
6 40
2 38
1
15 11 25
13
45
20 18
30
53
61
22
12 6
24
14 16 10 18 7 9, 11 4 10
17 19 20 8, 15 26, 29 1, 3, 5, 6
New proposals
23 2
13,21
12 22
30 25
27, 28
3, 12, 13, 17, 20, 24, 25, 26, 29, 37, 38, 40, 42, 43, 45, 47, 48
18
46
1 7 28 9, 10, 36 14 27
11 19 16, 31 2, 30
15, 39 22 8
Submitted proposals
23 33 49 5, 35
4, 6, 41, 44
34 32
21
2, 3, 4, 5, 7, 10, 11, 16, 18, 20, 22, 24, 25, 28, 32, 34, 36, 38, 41, 42, 47, 52, 54, 58, 65, 66
1, 15 12 13 8
6, 23, 60 37 26, 40
9 17, 35
22, 49 50 43 19
44 33, 21
Completed and ongoing
61 27, 29
31, 51, 57
45
48
56, 14
59
63
64
30, 39, 46, 53, 55, 62
precambrian phanerozoic
Paleozoic Mesozoic Cenozoic
Archean Proterozoic
Cambrian Ordovician Silurian Devonian Carboniferous Permian Triassic Jurassic Cretaceous Paleogene Neogene Q
4000 2500 541 485 443 419 359 299 252 201 ~ 145 66 23 2.5 0
Figure 10. Decadal map of ICDP drill sites ( 2004–2014 ) showing locations of completed, planned and proposed continental drilling projects, together with their
projected archival time-spans. Numbers along the chronostratigraphical timescale are in millions of years; note that out of a 145 sites, 52% of planned cores
overlap within the most recent 2.6 million years [ Quaternary ( P=Pleistocene; H=Holocene ) ]; whilst 4% overlap within the earliest 1500 million years of earth
history for which there is a preserved rock record ( modified from Soreghan and Cohen, 2013 ).21
THE SCIENCE PLAN—PREAMBLE ICDP
lines of longitude across the equator to thinking to bridge the gap between the
the poles provides tests for global chang- earth and social-system sciences.
es. It can provide estimates of the ampli-
fication of system sensitivity caused by Today’s strongly connected global proc-
positive feedbacks, to develop a general ess networks are highly interdepen
set of algorithmic approaches for quanti- dent systems that we do not understand
fying the way complex adaptive systems well (Helbing, 2013). These systems are
interact with one another, and how they vulnerable to failure and can become
get connected through nature’s incessant unstable at all scales even when external
compulsion for self-organisation into shocks are absent. As the complexity of
evolving patterns. In deeper time too, interactions in global networked palaeo-
overlapping sequences from ancient cra- systems becomes better understood, we
tons will likely link high-fidelity fluctu- may develop technologies to make the
ations in biogeochemistry systems and anthropogenic systems manageable so
early life. that fundamental redesign for future
systems may become a reality.
Understanding how complex self-orga-
nising systems respond to external We are at the threshold of new transdis-
forcing is important, especially the ciplinary thinking about earth system
emergence of feedbacks sometimes complexity, and there will be a long list
passing ‘points of no return’ without of relevant questions that we must ask
warning before approaching tipping of the cores from drilling programmes.
points (‘catastrophic bifurcations’).There Inspection of the spatial and tempo-
are now signs that tipping points can ral distribution of ICDP ’s archived and
be predicted when critical thresholds anticipated drill-core (Figure 10) pro-
are approaching, spatially as well as vides powerful argument for construc-
temporally (Rietker et al., 2004; Scheffer tive engagement and efficient design
et al., 2009; Carpenter et al., 2011; of time-overlapping coring across the
Carpenter, 2013; Dai et al., 2013). globe through collaborative drilling
projects to chart the connectomics of
With more deep-spatial and deep-time our planet from core to space; and from
data it may become possible then to the past into the future.
make more robust predictions about a
future Earth to strengthen cohesion with Acknowledgements
socio-economic and political systems,
and to develop a greater planetary cul- I have benefited greatly from 10 years
ture to combat looming crisis (Morin interactive discourse on the ICDP Sci-
and Kern, 1999; Hansen et al., 2013). ence Advisory Group, under the leader-
New endeavours like earth stewardship ship of Stephen Hickman, who can create
science can collate the required criti- order out of any chaos. I am grateful to
cal knowledge to stimulate self-organ- ICDP for their facilitating role and gen-
ised paradigm shifts in transdisciplinary erous funding and to Bastien Linol for
help with Figure 10.22 THE SCIENCE PLAN—PREAMBLE
ICDP
References
Ager, D. V.: The Nature of the Stratigraphical Record, Soreghan, G. S. and Cohen, A. S.: Scientific drilling and the
Halsted (Wiley), New York, 114 pp. (3rd edition 1992, evolution of the earth system: climate, biota, biogeo-
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Criticality, New York, Copernicus, 1996. Toniazzo, T., Lenton, T. M., Cox, P. M., Gregory, J.: Entropy
Ben-Jacobs, E.: When order comes naturally, Nature, 415, 370, and Gaia: is there a link between MEP and self-
doi: 10.1038/415370a, 2002. regulation in the climate system? In: Non-equilibrium
Blackburn, T. J., Olsen, P. E., Bowring, S. A., McLean, N. M., thermodynamics and the production of Enthropy
Kent, D. V., Puffer, J., McHone, G., Rasbury, E. T., (Eds. Kleidon, A. and Lorenz, R. D.), Springer, Berlin,
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Camazine, S., Deneubourg, J.-L., Franks, N. R., Sneyd, J.,
Theraulaz, G., Bonabeau, E.: Self-Organisation
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Carpenter, S. R.: Complex systems: Spatial signatures
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Carpenter, S. R., Cole, J. J., Pace, M. L., Batt, R., Brock, W. A.,
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Shifts: A Whole-Ecosystem Experiment, Science, 322,
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Dai, L., Korolev, K. S., Gore, J.: Slower recovery in space
before collapse of connected populations, Nature 496,
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Hansen, J. et al.: Assessing “Dangerous Climate Change”:
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Helbing, D.: Globally networked risks and how to respond,
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Kleidon, A., Lorenz, R. D.: Non-equilibrium thermodynamics
and the production of entropy: Life, Earth, And Beyond
(understanding Complex Systems), Springer, Berlin,
260 pp., 2005.
Lovelock, J.E.: Gaia as seen through the atmosphere,
Atmospheric Environment Vol. 6, Pergamon Press,
579-580, 1972.
Morin, E. and Kern, A. B.: Homeland Earth: a Manifesto
for the new Millenium. Advances in system theory,
complexity and the human sciences, Hampton Press,
Inc. NJ., 153 pp., 1999.
Odem, H. T.: Self-Organisation, Transformity and Informa-
tion, Science 242, 1132–1139, 1988.
Prigogine, I.: Order out of Chaos, Toronto, Bantam Books,
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Rietkerk, M., Dekker, S. C., de Ruiter, P. C., van de Koppel, J.:
Self-Organised Patchiness and Catastrophic Shifts in
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Rudwick, M. J. S.: Bursting the Limits of Time—The recon-
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Scheffer, M., Bascompte, J., Brock, W. A., Brovkin, V.,
Carpenter, S. R., Dakos, V., Held, H., van Nes,
E. H., Rietkerk, M., Sugihara, G.: Early-warning signals
for critical transitions, Nature 461, 53–59, 2009.PAVING THE WAY FORWARD —THE SCIENCE PLAN ACTIVE FAULTS AND EARTHQUAKES GLOBAL CYCLES AND ENVIRONMENTAL CHANGE HEAT AND MASS TRANSFER THE UBIQUITOUS HIDDEN BIOSPHERE CATACLYSMIC EVENTS —IMPACT CRATERS AND PROCESSES
24 SCIENCE PLAN ELEMENTS
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ACTIVE FAULTS AND EARTHQUAKES
Jim Mori Disaster Prevention Research Institute, Kyoto University, Kyoto, Japan
William Ellsworth U.S. Geological Survey, Menlo Park, USA
Figure 11. An automobile crushed under the third story of an apartment building in the Marina District,
San Francisco — the Loma Prieta earthquake in 1989, magnitude 6,9
Lay of the land takes time and is an ongoing endeav-
our. However, contributions to scien-
A single earthquake and associated tsu- tific knowledge, as described in the fol-
nami in a populated region can kill tens lowing sections, address critical issues
of thousands of people and cause huge such as establishing occurrence rates of
economic losses that are a significant severe events and evaluating the inten-
percentage of the GDP of the strick- sity of the damaging ground shaking as
en country. The developing countries needed for seismic zoning and emer-
(the 2010 M7.0 Haiti earthquake killed gency measures planning. Also, drill-
over 100,000 people) and technologi- ing projects draw public attention to the
cally advanced countries (the M9.0 2011 seismic hazards of a region and can be
Tohoku earthquake in Japan caused sev- the catalyst for effective education and
eral hundred billion dollars of damage) outreach efforts.
are all prone to these disasters. A few
research boreholes drilled into active Earth tremors and earthquakes can be
faults and equipped with monitoring induced; with the increasing production
tools is not going to immediately reduce of shale gas and shale oil, the building
the damage from earthquakes; this of reservoirs for hydroelectricity, and25 SCIENCE PLAN ELEMENTS / ACTIVE FAULTS AND EARTHQUAKES
ICDP
the pumping of fluids into underground We have begun to answer some of the
storage areas, it is clear that the last dec- key questions raised 20 years ago when
ade has seen a dramatic increase in the the first boreholes into fault zones were
earthquakes associated with human being planned, and significant progress
activities (e.g. Gupta, 2002; Ellsworth, has been made in answering these ques-
2013). A better understanding of condi- tions.
tions and mechanisms of these seismic • Why are major plate-boundary
events should lead to better-informed faults like the San Andreas Fault weak?
policies for the regulation and operation • How do stress orientations and
of a number of human activities. magnitudes vary across the fault zone?
• What are the width and structure
Past accomplishments in ICDP (geological and thermal) of the princi-
pal slip surface(s) at depth?
During the last two decades, deep bore- • What are the mineralogies, defor-
hole drilling into fault zones has opened mation mechanisms and frictional
new fields of research for a better properties of the fault rocks?
understanding of earthquake process- • How is energy partitioned within
es. Land-based drilling projects on the the fault zone between seismic
Nojma Fault Japan, (Ando et al., 2001), radiation, frictional heating, commi-
San Andreas Fault, USA (Zoback et al., nution and other processes?
2011), Chelungpu Fault, Taiwan, (Ma et
al., 2006), Wenchuan Earthquake Fault, Fundamental open questions
(China, Li et al., 2012), Gulf of Corinth,
Greece (Cornet et al., 2004), and Alpine In the next decade, future fault zone Figure 12. The complexity of real fault zones.
Fault, New Zealand, (Toy et al., 2013a) projects will continue to improve our
along with ocean drilling in subduc- understanding of the structure and
tion zones of the Nankai Trough (Tob- processes of active faults which result in
in et al., 2009), Japan Trench (Chester large earthquakes, by focusing on these
et al., 2013), and Costa Rica (Vannuc- issues:
chi et al., 2013), have obtained valuable • How do earthquakes nucleate?
samples and measurements from active • How do they propagate?
fault zones from depths reaching several • Why do they stop?
kilometres. We have obtained a much • What controls the levels of ground
better knowledge of the physical prop- motion during earthquakes?
erties of active fault zones that produce • What controls the frequency and
large damaging earthquakes. An impor- size of earthquakes
tant result is recognition of the immense • How is fluid involved and how
complexity observed in the fault zone does fault permeability vary during
rocks, including their varied structur- earthquakes?
al and chemical characteristics, along • How does stress magnitude
with the associated fluid properties and orientation vary during the
(Figure 12). earthquake cycle?26 SCIENCE PLAN ELEMENTS / ACTIVE FAULTS AND EARTHQUAKES
ICDP
Future scientific targets structure of fault zones, flow paths of
fluids and the role chemical reactions of
From discussion at the 2013 ICDP introduced waters play in modifying the
Science Meeting, we have identified permeability structure. Permeabilities
research areas that can be advanced can vary by orders of magnitude across
through drilling projects and have the varying geological structures and have
potential for producing critical new a strong effect on the frictional proper-
results for understanding earthquakes. ties of the fault during large earthquakes
(e.g. Tanikawa et al., 2013). Borehole Figure 13. Start of drilling at the GONAF location
in Tuzla, Turkey
Induced earthquakes studies of the fluid-flow and pressure
It has been recently recognised that an transmission regimes may thus produce
increasing number of earthquakes are important results.
associated with human activities such
as reservoir filling, mining, waste-water Borehole observatories
injections, and CO2 sequestration. The last decade has seen a rapid increase
Induced earthquakes of small to moder- in the development and installation of
ate size have caused damage throughout borehole instrumentation on the San
the world (e.g. 1967 Koyna, India; 2011 Andreas Fault (Zoback et al., 2011),
Oklahoma; 2006 Basel, Switzerland). In Chelungpu Fault (Ma et al., 2012), North
many of the documented cases in the lit- Anatolian Fault (Bohnhoff, 2013), and
erature, variations in pore fluid pressure at various other locations around the
are implicated as the primary physical world (Figure 16). These instruments
mechanism that triggers earthquakes record a variety of types of data such
(e.g. Gupta, 2002; Deichmann and Gia- as seismic waves, deformation and
rdini, 2009; Ellsworth, 2013). Major tilt, temperature, and fluid pressure.
questions remain about how fluid pres- Boreholes provide unique access into
sure migrates through the Earth, and the nearfield region of the earthquake
how ancient faults can be reactivated source and provide extremely low noise
by this mechanism. Resolution of these conditions for observing the system,
and other questions requires in-situ which is not attainable at the Earth’s sur-
observations in boreholes in the source face. ICDP can play an important role
regions of these earthquakes. ICDP can in coordination of instrument develop-
play an important role in investigating ment among different groups and sup-
the physical and chemical processes and port for deployment at important sites
evaluating hazard implications of such on active seismic regions.
human-induced seismic events.
For example, little is known about the
Role of fluids source mechanisms of low-frequency
The importance of the effects of water earthquakes that may occur in more
for both natural and induced earth- ductile regions of the crust. Borehole
quakes has long been appreciated. observations of these and other types of
However there is currently only limit- seismic and deformation events can lead
ed information about the permeability to a better understanding of the wide27 ICDP
DOWNHOLE EARTH OBSERVATORY
Marco Bohnhoff, Georg Dresen GFZ— German Research Centre for Geosciences, Germany
High-resolution downhole research for decades, demonstrating band as well as GPS and strain meter
seismic monitoring that the effort needed for implement- measurements. Microseismicity will
In order to perform high-resolution ing permanent downhole monitoring be monitored at low magnitude-detec-
seismic monitoring of critical faults systems pays off on the long term. tion threshold and with high precision
overdue to generate large earth- not achievable with surface record-
quakes, it is necessary to place The ICDP-GONAF project ings. Using the downhole observa-
geophones in low-noise environments The North Anatolian Fault Zone in tions, the driving physical processes
and as close as possible to the fault Turkey has produced several large along a transform fault segment,
zone. Such conditions can be met only (M>7) earthquakes in the historic past which is in the final state of its seismic
by drilling boreholes located close to leaving the Marmara Sea segment cycle, will be studied prior, during
the target fault. Beginning in the late as the only part of the entire fault and after a large (M 7+) earthquake.
80s in the USA and Japan, borehole zone that has not generated a major Furthermore, the role of structural
installations have been successfully earthquake since 1766. Currently, heterogeneities of the NAFZ below
operated throughout the last decades. there is a high probability for a major the Sea of Marmara will be investi-
Much experience has been gained earthquake less than 20 km from the gated for slip distribution, nucleation
from these efforts, in particular from roughly 13 million people who live process, and magnitude of the pend-
the local high-resolution seismic in Istanbul. In order to monitor this ing Marmara earthquake.
network ( HRSN ) on the San Andreas critical part of the fault, a borehole
Fault in California and the Hi-net in Geophysical Observatory at the North Drilling holes is more than just
Japan. Such installations are still rare Anatolian Fault zone ( ICDP-GONAF collecting samples. Installation of sen-
but have produced unique earth- project) has been initiated. GONAF sitive instruments in boreholes allows
quake waveform recordings, provid- is a joint research venture between us to directly access the underground
ing state-of-the-art seismological GFZ Potsdam and the Turkish Disaster where earthquakes nucleate. This
and Emergency Presidency ( AFAD ) is the key for near-source earthquake
in Ankara. When completed, it will monitoring providing the base for im-
comprise an eight-station earthquake proved seismic risk and also resource
downhole observatory, each equipped management.
with vertical arrays of seismometers
in 300 m deep boreholes on the main-
land and on the Princes Islands being
located within 3 km to the fault.
Key challenges
The principal objectives of the
GONAF project are to monitor micro-
seismic activity and deformation proc-
esses in the broader Istanbul region
using downhole seismic observations
over the entire seismic frequency
Figure 14. Recordings of the Tuzla earthquake
swarm of 201328 SCIENCE PLAN ELEMENTS / ACTIVE FAULTS AND EARTHQUAKES
ICDP
range of physical mechanisms for strain Deep mines also provide a natural labo-
accumulation and release in the crust. ratory for studying failure mechanisms.
They provide straightforward access to
Experiments on core material the locus of deformation induced by
and modeling mining and can be extensively instru-
Laboratory analysis of rock, fluid and mented with seismic and deformation
gas samples from active faults obtained instrumentation in the extreme near-
from depth provide important infor- field of the process, such as in the South
mation on the physical and chemical African goldmines (e.g. Ogasawara et al., Figure 15. Affected dam after the Jiji earthquake
in 1999, Taiwan
properties of fault deformation mech- 2013).
anisms. These mechanisms span the
range from continuous creep to sudden Another potential experiment uses
slip in earthquakes (e.g. Ikari, 2013). The injection of water into a fault zone to
rate dependence of friction and tempo- produce small earthquakes. An experi-
ral evolution of fault-zone permeabil- ment of this type was done at Rangely,
ity are just two of the important para- Colorado, USA more than 40 years ago
metres that can only be obtained from when an array of boreholes into a fault
direct sampling of faults in-situ. Under- zone were used to modulate the rate of
standing of the physical and chemical earthquakes (Raleigh et al., 1976). This
processes that lead to the development experiment verified the effective stress
of the fault core where the great major- mechanism for triggering earthquakes
ity of the sliding occurs and surrounding by modulating the pore fluid pressure
damage zone requires the retrieval of a inside the fault. Today, critical questions
broad suite of samples of fault rocks and remain about the feedback between fault
fluids. Such physical data is especially movement and the enhancement of per-
needed to constrain dynamic modeling meability within a fault as it moves in a
of earthquake ruptures (Avouac et al., series of small earthquakes, or the con-
2013) trols on the magnitude of earthquakes
induced by this mechanism.
In-situ experiments
To bridge the gap between simulated Geological records of tsunamis
earthquakes in the laboratory (milli- and earthquakes
metre to metre scale) and the kilometre Geologists are always seeking new
dimensions of natural earthquakes, we methods for extending the record of
need better knowledge about the behav- past earthquakes and other large cata-
ior of materials for in-situ conditions. strophic events beyond the written his-
Experiments at depth in real fault zones torical record. Coastal deposits from
can study the conditions for producing large tsunamis (produced by earth-
earthquakes using small displacements quakes, volcanic events, meteorite
of the actual rock masses under natural impacts), as identified in borehole cores,
stress and temperature conditions (e.g. can be used to gain a better knowledge
Henry et al., 2013). of such events. Giant M earthquakes,
such as the recent 2004 Sumatra, Indo-29 SCIENCE PLAN ELEMENTS / ACTIVE FAULTS AND EARTHQUAKES
ICDP
Tiberian Fault
S France Gulf of Corinth Aigion Fault Wenchuan Fault
San Andreas Fault SE Iberia N Anatolian Fault
Nojima Fault
Chelungpu Fault
Koyna dam
Fault zone drilling and borehole observatory South African Goldmine
Borehole observatory
In situ experiment
Alpine Fault
Figure 16. Locations of continental fault-zone drilling projects, borehole observatories and in-situ experiments discussed in the Active Faults and Earthquake
Processes session at the ICDP Science Conference.
nesia and 2011 Tohoku, Japan earth- Capture the complete
quakes produced global-scale tsuna- earthquake cycle
mis which can be studied using coastal Past drilling projects have investigated
boreholes (e.g. Fujiwara, 2013). Also fault zones soon after the occurrence of
records from regions that have very high a large earthquake (e.g. Chelungpu and
sedimentation rates, such as glacial and Wenchuan), while others have studied
lake deposits, can provide new opportu- physical characteristics of faults in vari-
nities for extending earthquake histories ous stages of the earthquake cycle. In the
(Toy et al., 2013b). future, we envision a large-scale project
to make detailed subsurface observa-
Deep processes and tectonics tions before, during and after a large
In addition to providing detailed fault- earthquake. For such studies, it is essen-
zone characterisations, observations tial to measure the physical state of the
made in boreholes provide the only fault before the event and have in place a
direct means for measuring the state of borehole that can rapidly be reoccupied
stress in the Earth. Knowledge of the to observe the rapid temporal evolution
orientation and magnitude of the stress of the fault immediately after a large
field and its spatial variability may hold slip event. Clarifying time-dependent
the key to understanding the variability changes in the physical and chemical
in earthquake rupture and seismic wave properties should lead to important new
radiation, as well as providing impor- insights for understanding the whole
tant constraints on regional tectonic process of earthquake occurrence.
processes and deeper mantle processes.30 SCIENCE PLAN ELEMENTS / ACTIVE FAULTS AND EARTHQUAKES
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Drilling issues Recommendations
Reaching the depths of the seismogenic 1. Studying earthquakes using drilling
zone where earthquakes nucleate has provides unique opportunities for high-
always been a challenge for fault-zone profile, high-scientific return investi-
drilling projects. The maximum depth gations that hold the potential to revo-
reached in a fault-zone drilling project lutionise our understanding of active
was 3.0 km at SAFOD, although, for faulting and earthquake processes.
comparison, exploratory oil and gas Figure 17. Two scientists holding a drill core that
contains the Alpine Fault, New Zealand.
wells have been drilled to over three 2. These questions are of high interest to
times this depth. For core sampling, the public, so appropriate education and
there is the desire to reach greater depths outreach efforts should be considered
and pressures which may be more rep- from the planning stages. Furthermore,
resentative of the overall fault condi- serious consideration should be given to
tions of a large earthquake. Obtain- the practical applications of the scientif-
ing fault zone cores from depths of ic results to seismic hazard evaluations
5 to 10 km will need new cost-effective and mitigation.
techniques for deep drilling, including
advanced techniques for better recovery 3. ICDP workshops should be intro-
of the fragile fault zone. duced to discuss broader logistical and
design issues common to all earth-
For borehole observatories, such as the quake investigations, rather than just
GONAF array along the North Ana- the development of specific drilling
tolian Fault in Turkey (Bohnhoff et al., proposals. Possible topics that would
2013), more numerous sites with rela- be of interest to the scientific commu-
tively shallow boreholes are needed to nity include technologies in borehole
emplace seismometres, strainmetres and observatories, applications for seismic
other instruments in competent rock at hazard assessment, and a roadmap for
a depth of a few hundred metres. ICDP a coordinated global fault zone drilling
could lead efforts to develop efficient programme.
drilling and deployment strategies for
such borehole installations.
Also, improved logging tools and new
techniques for analysing cuttings are
needed to optimise the information
gained during the drilling.You can also read
