The Earth's climate system has demonstrably changed on both global and regional scales since the pre-industrial era, with some of these changes attributable to human activities (IPCC, 2001). Further amplified global warming since the 1970s, a rising sea level, regional climate shifts, and extreme climate events severely impact the human habitat. We have an obligation to conduct research that provides a mechanistic understanding of present and past variations in regional and global climate. Of greatest concern regarding the human perturbation of climate is not what we know but rather what we do not know. While some changes are likely to be milder than expounded in the popular press, there are others that may be unexpectedly severe, too.
It has been posited that the Deep Biosphere harbours a greater biomass than the mass of all the living cells, prokaryotic and eukaryotic, in the surface regions of the biosphere. These estimates of the extent of the Deep Biosphere have been made by projecting and extrapolating from data collected from a very limited number of boreholes in marine and terrestrial environments. In truth, we have only very limited data on which to base these estimates. The lower depth limit of the biosphere has not been reached in any borehole studies that have included a microbiological component, and the factors that control the abundance and activities of microbes at depth and the lower depth limit of life are still poorly understood.
Each day thousands of small bodies of extraterrestrial matter collide with Earth but large celestial travellers producing impacts structures of 100 of meters to hundreds of kilometers are rare. In the Phanerozoic eon, a giant impact in Mexico created a 200 km wide crater and devastations affecting the whole planet. This event wiped out major portions of the fauna and flora on the Earth and was strong enough to define the transition from the Cretaceous to the Tertiary era with the end of the dinosaurs and the rise to the dominance of the mammals. Thus, large impacts are the fastest geological events creating new ground for evolution.
Volcanic eruptions may affect climate and the environment from regional to global scale. On global scale they may contribute to global climate change through compositional changes in the earth's atmosphere. This can either be warming of the earth’s atmosphere through release of CO2 and water vapour which act as greenhouse gases, or global cooling through suspended volcanic particles. Dust and ash, and to an even greater extend sulphuric gases which form droplets of sulphuric acid can block out the earth's sunlight, hence reducing solar radiation (http://www.geology.sdsu.edu). Understanding the interplay between volcanic activities and climate variations requires knowledge of both volcanic and climate history.
Commonly the biosphere is defined as the small zone on Earth in which living organisms can exist. But the extend of deep life is not ending where humus-rich soil hits bedrock. An unbelievable richness of bacteria, viruses and archea is dwelling at depth to several thousand meters below ground and in temperatures of up to 122° C. With their metabolism they contribute critically to the generation of carbohydrate resources and they even contribute to the formation of several different mineral resources.
Volcanism, and more broadly -- where melting is not involved -- thermal regimes, are a fundamental aspect of planets. Radioactive decay of parent nuclides (U, Th, K), residual heat during Earth’s accretion, and crystallization are the main processes that generate heat inside the Earth; heat so intense that it melts rock and drives tectonic processes and planetary differentiation. Geothermal energy can be tapped from the Earth's natural heat at volcanoes or mantle plumes. When magma moves upward to depths of only a few kilometres it transfers heat by interaction with groundwater. The groundwater then circulates by convection and forms geothermal reservoirs. At shallower depth, decompression causes additional melting of rock and magma degassing which may leads to in volcanic eruptions. Holes drilled into a subsurface geothermal system allow rapid transfer of hot water or steam to the surface to drive turbines and generate electrical power.
The world’s population is expected to rise by 1.5 billion in the next 15 years, with most population growth occurring in the emerging economies of China and India. The increase of people expected by 2050 exceeds the world population that existed in 1950. Accompanying this growth is a relentless demand for natural resources to sustain economic development and to support rising standards of living. A key priority for the global community, now, and in the future, is to identify and develop increasingly sparse natural resources, including mineral resources, hydrocarbon reservoirs, and water, while at the same time protecting the environment.
At the borders of the major tectonic plates on Earth tremendous energy is released in earthquakes, through volcanoes and in mountain building. At the same time most of the erosion and deposition of sediments is culminating along the plate margins. Along with these recycling processes several minerals and organic matter are concentrated to many of the most important resources on Earth
Active faulting is by far the most common earthquake generating process beside volcanic activities, deep fluid circulation and collapsing of caverns and underground mines. The earthquake hazard is not only generated by ground shaking and ground displacement, but also by phenomena such like ground liquefaction, landslides and tsunamis. However, little is known on the mechanism of stress accumulation and rupture propagation and the chemical and physical processes that leads to stress release and why e.g. some faults are creeping while others are locked. Today we are still far away from reliable earthquake prediction. Only deep drilling provides access to seismogenic zones for monitoring and to retrieve samples from there to improve our understanding of fault processes.
Volcanic eruptions are one of Earth's most dramatic and violent agents of change. Volcanic eruptions can be placed into two general categories: those that are explosive, such as e.g. Mount St. Helens or large caldera volcanos, such as Campi Flegrei, and those that are effusive, such as the Hawaiian Hot Spot. Powerful explosive eruptions can drastically alter land and water for tens of kilometers around a volcano. Eruptions often force people living near volcanoes to abandon their land and homes, sometimes forever. Those living farther away are likely to avoid complete destruction, but their cities and towns, crops, industrial plants, transportation systems, and electrical grids can still be damaged by tephra, ash, lahars, and flooding. Some volcanoes exhibit precursory unrest that if detected and analyzed in time allows eruptions to be anticipated.
Throughout Earth’s history, hundreds of impacts have been reported, with some occurrences causing deaths, injuries, property damage or other significant consequences. Currently ca. 170 impact craters are known on Earth; about one third of those structures are not exposed on the surface and can only be studied by geophysics or drilling. The impact origin of geological structures can only be confirmed by petrographic and geochemical studies; thus, it is of crucial importance to obtain samples of subsurface structures. In addition, also structures that have surface exposures often require drilling and drill cores, to obtain information of the subsurface structure, to provide ground-truth for geophysical studies, and to obtain samples of rock types not exposed at the surface. For many years drilling of impact craters was rarely done for reasons unrelated to their impact origin.
Plate margins are areas where the most life-threatening geological phenomena occurs: huge earthquakes on subduction megathrusts, including the 2011 Tohoku earthquake, the 2004 Sumatra-Andaman earthquake (both Mw 9.0 and with the associated devastating tsunami), the 1960 Southern Chile earthquake (M 9.5), the 1964 Alaska earthquake (M 9.2), and the 1923 Kanto earthquake (M 7.9) that destroyed Tokyo, the capital of Japan. Accompanying geohazards include tsunamis, landslides, powerful volcanic eruptions, and other threats to human life, infrastructure and economics, and to ecosystems. Given that 60% of Earth's population lives within the frontal 50 km of the coast, there is a strong need for scientific and economic efforts, to shed light on the processes responsible for such ocean margin geohazards as well as their mitigation. Scientific drilling has a high potential to such studies and must be an integral and indispensable part of this effort.
This third ICDP Science Plan came about by engaging the international science community and it lays out some of the big open questions that confront the earth sciences. It suggests ways to answer these questions by scientific drilling. Read more
Drilling the Cretaceous Songliao Basin in China
Scientific Drilling in full swing
Spud in of the Continental Scientific Drilling Project of Cretaceous Songliao Basin (DPCSB), the deepest targeted ICDP co-funded project, was on April 13, 2014 using the new Chinese rig “Crust-I” with 10 km depth capacity. Read more
AGU 2015 Spring Meeting in Montréal December 18, 2014
May 3-7, 2015 in Montréal, Canada
The next AGU-GAC-MAC-CGU joint assembly will be held in Montréal – 3-7 May 2015. You are kindly invited to join the session
Exploring the subsurface through Scientific Drilling: contributions from ICDP and IODP
Drilling explorations in the oceans and on the continents provide means to tackle challenging geoscientific themes of socio-economic relevance such as long-term climate and environmental changes, earthquakes and volcanism, or unconventional energy resources. By monitoring, drilling, sampling, and analyzing the subsurface at locations where critical questions can best be approached, the International Continental Scientific Drilling Program (ICDP) and the International Ocean Discovery Program (IODP) are the key for advances in the understanding of our planet. This interdisciplinary session invites presentations on recent, ongoing and future IODP/ICDP projects of all kind and from everywhere. It seeks contributions presenting results arising from scientific drilling, new methods applicable to such efforts and new interdisciplinary approaches to interpret deep and hidden archives accessible only by drilling.
Multi-Well Deep Underground Laboratory in the Songliao BasinJune 27, 2015
June 27 to 30, 2015 in Beijing, PR China
The plan is to establish a deep multi-well (1000 - 6000 m) underground laboratory (MW-DUL) using a large number of existing boreholes in the Songliao Basin, NE China. The objectives are 1) detection and exploration of the deep biosphere; 2) geological CO2 sequestration; 3) seismic and volcanic activity monitoring; 4) sharing well-characterized samples containing possible abiotic methane or other hydrocarbons that can be analyzed in multiple laboratories; 5) sharing data on samples containing abiotic hydrocarbons; and 6) developing new international scientific collaborations. Because an extensive infrastructure exists within and around the Songliao Basin, this basin is an ideal site in which to create such a laboratory. The planning workshop will be held in Beijing, China, from June 27 to 30, 2015.