Full-time professor at the Free University of Brussels, Belgium
apreat@gmail.com
apreat@ulb.ac.be
• Department of Earth Sciences and Environment
Res. Grp. - Biogeochemistry & Modeling of the Earth System
Sedimentology & Basin Analysis
• Alumnus, Collège des Alumni, Académie Royale de Sciences, des Lettres et des Beaux Arts de Belgique (mars 2013). http://www.academieroyale.be/cgi?usr=2a8crwkksq&lg=fr&pag=858&rec=0&frm=0&par=aybabtu&id=4471&flux=8365323
• Prof. Invited, Université de Mons-Hainaut (2010-present-day)
• Prof. Coordinator and invited to the Royal Academy of Sciences of Belgium (Belgian College) (2009-
present day)
• Prof. partim to the DEA (third cycle) led by the University of Lille (9 universities from 1999 to 2004) - Prof. partim at the University of Paris-Sud/Orsay, European-Socrates Agreement (1995-1998)
• Prof. partim at the University of Louvain, Convention ULB-UCL (1993-2000)
• Since 2015 : Member of Comité éditorial de la Revue Géologie de la France http://geolfrance.brgm.fr
• Since 2014 : Regular author of texts for ‘la Revue Science et Pseudosciences’ http://www.pseudo-sciences.org/
• Many field works (several weeks to 2 months) (Meso- and Paleozoic carbonates, Paleo- to Neoproterozoic carbonates) in Europe, USA (Nevada), Papouasia (Holocene), North Africa (Algeria, Morrocco, Tunisia), West Africa (Gabon, DRC, Congo-Brazzaville, South Africa, Angola), Iraq... Recently : field works (3 to 5 weeks) Congo- Brazzaville 2012, 2015, 2016 (carbonate Neoproterozoic).
Degree in geological sciences at the Free University of Brussels (ULB) in 1974, I went to Algeria for two years teaching mining geology at the University of Constantine. Back in Belgium I worked for two years as an expert for the EEC (European Commission), first on the prospecting of Pb and Zn in carbonate environments, then the uranium exploration in Belgium. Then Assistant at ULB, Department of Geology I got the degree of Doctor of Sciences (Geology) in 1985. My thesis, devoted to the study of the Devonian carbonate sedimentology of northern France and southern Belgium, comprised a significant portion of field work whose interpretation and synthesis conducted to the establishment of model of carbonate platforms and ramps with reefal constructions.
I then worked for Petrofina SA and shared a little more than two years in Angola as Director of the Research Laboratory of this oil company. The lab included 22 people (micropaleontology, sedimentology, petrophysics). My main activity was to interpret facies reservoirs from drillings in the Cretaceous, sometimes in the Tertiary. I carried out many studies for oil companies operating in this country.
I returned to the ULB in 1988 as First Assistant and was appointed Professor in 1990. I carried out various missions for mining companies in Belgium and oil companies abroad and continued research, particularly through projects of the Scientific Research National Funds (FNRS).
My research still concerns sedimentology, geochemistry and diagenesis of carbonate rocks which leads me to travel many countries in Europe or outside Europe, North Africa, Papua New Guinea and the USA, to conduct field missions.
Since the late 90's, I expanded my field of research in addressing the problem of mass extinctions of organisms from the Upper Devonian series across Euramerica (from North America to Poland) and I also specialized in microbiological and geochemical analyses of ancient carbonate series developing a sustained collaboration with biologists of my university. We are at the origin of a paleoecological model based on the presence of iron-bacterial microfossils, which led me to travel many countries in Europe and North Africa. This model accounts for the red pigmentation of many marble and ornamental stones used in the world. This research also has implications on the emergence of Life from the earliest stages of formation of Earth, as well as in the field of exobiology or extraterrestrial life ...
More recently I invested in the study from the Precambrian series of Gabon and Congo. These works with colleagues from BRGM (Orléans) are as much about the academic side (consequences of the appearance of oxygen in the Paleoproterozoic and study of Neoproterozoic glaciations) that the potential applications in reservoir rocks and source rocks of oil (in collaboration with oil companies).
Finally I recently established a close collaboration with the Royal Institute of Natural Sciences of Belgium to study the susceptibility magnetic signal from various European Paleozoic series. All these works allowed me to gain a thorough understanding of carbonate rocks (petrology, micropaleontology, geobiology, geochemistry, sequence stratigraphy, diagenesis) as well in Precambrian (2.2 Ga and 0.6 Ga), Paleozoic (from Silurian to Carboniferous) and Mesozoic (Jurassic and Cretaceous) rocks. Recently (2010) I have established a collaboration with Iraqi Kurdistan as part of a government program to boost scientific research in this country.
My research led me to publish about 180 papers in international and national journals and presented more than 170 conference papers. I am a holder of eight courses at the ULB (5 mandatory and 3 optional), excursions and field stages, I taught at the third cycle in several French universities and led or co-managed a score of 20 Doctoral (PhD) and Post-doctoral theses and has been the promotor of more than 50 Masters theses.
Deep in the ocean’s twilight zone, swarms of ravenous single-celled organisms may be altering Earth’s carbon cycle in ways scientists never expected, according to a new study from Florida State University researchers.
In the area 100 to 1,000 meters below the ocean’s surface — dubbed the twilight zone because of its largely impenetrable darkness — scientists found that tiny organisms called phaeodarians are consuming sinking, carbon-rich particles before they settle on the seabed, where they would otherwise be stored and sequestered from the atmosphere for millennia.
This discovery, researchers suggest, could indicate the need for a re-evaluation of how carbon circulates throughout the ocean, and a new appraisal of the role these microorganisms might play in Earth’s shifting climate.
The findings were published in the journal Limnology and Oceanography.
The sun has been blank for 21 days–3 whole weeks without sunspots. To find an equal number of consecutive spotless days in the historical record, you have to go back to July-August 2009 when the sun was emerging from an unusually deep solar minimum. Solar minimum, welcome back!
While NBC News might think that 68,000 page views per month is impressive, in comparison to our regular daily traffic on WUWT, it pales in comparison. For example, here is a screencap from my WordPress dashboard from yesterday, July 16th, which was a fairly typical summer day for WUWT. Note that it shows 92,467 page views in one day.
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What’s most interesting is that while there’s been a slow, almost imperceptible increase in the phrase “climate change”, the search phrase “global warming” is getting far less use than it did when data was first collected, back in 2004. Right now, both “climate change”, and “global warming” have low interests.
There may be more than a quadrillion tons of diamond hidden in the Earth’s interior, according to a new study from MIT and other universities. But the new results are unlikely to set off a diamond rush. The scientists estimate the precious minerals are buried more than 100 miles below the surface, far deeper than any drilling expedition has ever reached.
The ultradeep cache may be scattered within cratonic roots — the oldest and most immovable sections of rock that lie beneath the center of most continental tectonic plates. Shaped like inverted mountains, cratons can stretch as deep as 200 miles through the Earth’s crust and into its mantle; geologists refer to their deepest sections as “roots.”
In the new study, scientists estimate that cratonic roots may contain 1 to 2 percent diamond. Considering the total volume of cratonic roots in the Earth, the team figures that about a quadrillion (1016) tons of diamond are scattered within these ancient rocks, 90 to 150 miles below the surface.
Sometimes a chance comment sets off a whole chain of investigation. Somewhere recently, in passing I noted the idea of the slope of the temperature gradient across the Pacific along the Equator. So I decided to take a look at it. Here is the area that I examined.
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I’ve written about this temperature gradient before, in a post called The Tao of El Nino. If you take time to read that post, this one will make more sense. …
by A. Préat, 16 juillet 2018 in ScienceClimatEnergie
L ’hydrogène, un gaz peu abondant…
L’ hydrogène n’est présent qu’à concurrence de 1 ppm ( = une ‘partie par million’, soit 0,0001%) dans l’atmosphère : autant dire que c’est presque rien. D’où vient-il ? Peut-on en produire de grandes quantités à partir de ressources naturelles (géologie) ou artificielles (chimie) ? Autant de questions que de plus en plus d’industriels, de scientifiques, de politiques et de citoyens (?) se posent pour faire face à ce qu’il est convenu d’appeler la transition énergétique tant à l’ordre du jour, à raison ou à tort, là n’est pas l’objet de cet article. Comme nous le verrons par la suite, l’exploitation directe de l’hydrogène naturel n’est pas encore rentable et il faudra sans doute le produire à partir d’une autre source d’énergie, car il n’est pas lui-même une source d’énergie, mais au contraire un simple vecteur d’énergie.A l’heure actuelle il n’est donc pas exploité à une échelle suffisante en raison des contraintes géologiques et économiques, et il faut le synthétiser [1]. C’est ce que réalise aujourd’hui l’industrie principalement en vue de la fabrication de l’ammoniac pour les engrais ou des plastiques.
Unearthed new evidence (Mangerud and Svendsen, 2018) reveals that during the Early Holocene, when CO2 concentrations hovered around 260 ppm, “warmth-demanding species” were living in locations 1,000 km farther north of where they exist today in Arctic Svalbard, indicating that summer temperatures must have been about “6°C warmer than at present”.
Proxy evidence from two other new papers suggests Svalbard’s Hinlopen Strait may have reached about 5 – 9°C warmer than 1955-2012 during the Early Holocene (Bartels et al., 2018), and Greenland may have been “4.0 to 7.0 °C warmer than modern [1952-2014]” between 10,000 and 8,000 years ago according to evidence found in rock formations at the bottom of ancient lakes (McFarlin et al., 2018).
In these 3 new papers, none of the scientists connect the “pronounced” and “exceptional” Early Holocene warmth to CO2 concentrations.
Hurricane threat to East Coast due to natural factors
First at his most recent Saturday Summary, the 40-year meteorologist first warns that in-close developing hurricanes of the sort seen in the 1930s are a risk to the US East Coast this year, due the current Atlantic temperature pattern. The reason has nothing to do with CO2 in the atmosphere, but because of natural sea surface temperature cycles.
Sea surface temperatures see “pretty dramatic turnaround”
Diesel cars may still be the most sensible option for many families who drive long distances, the transport secretary Chris Grayling said yesterday.
Despite a pledge to see the end of petrol and diesel vehicles on UK roads by 2040, Mr Grayling said new diesels were not destined for the scrapheap just yet.
He said: ‘If you are doing long distances on the motorway, maybe the new generation of diesel engines are the right option for now.
The Climategate emails expose to our view a world that was previously hidden from virtually everyone.
This formerly hidden world was made up of a very few players. But they controlled those critical Intergovernmental Panel on Climate Change (IPCC) processes involv- ing the temperature records from the past, and the official interpretation of cur- rent temperature data. They exerted previously unrecognized influence on the “peer review” process for papers seeking publication in the officially recognised climate science literature from which the IPCC was supposed to rely exclusively in order to draw its conclusions.
L’ Anthropocène est la dernière création marketing d’un géologue. Avec un certain succès médiatique alors que les scientifiques s’y opposent fermement. Pourquoi ?
The ‘average’ world temperature for June 2018 was +0.21 deg C above the 1981 – 2010 mean. That represented a decline of about 0.65 deg C from the all-time high of this 39-year record, which was reached in early 2016. The 0.65 deg C decline represented more than 75% of the amount by which the average temperature had exceeded the 1981 – 2010 mean at the highest point. Suddenly the fact that some large number of “all-time highs” was being set at the end of June does not seem very significant.”
by A. Alam Khan, February17, 2018 in GeoScienceFrontiers
Highlights
• Global warming and polar ice-melt not contribute to sea level rise.
• Melting of huge volume of floating sea-ice around polar region cool ocean-water preventing thermal expansion.
• Polar ice melting re-occupy same volume of the displaced water causing no sea level rise.
• Gravitational attraction of the earth plays a dominant role against sea level rise.
• Melting of land ice in the polar region allow crust to rebound elastically for isostatic balancing through uplift should cause sea level to drop relatively.
A University of Aizu team has identified two distinct Indo-Pacific processes shaping the unique features and extraordinary ferocity of super El Ninos. A systematic analysis of these processes and their interactions will improve forecasts of the elusive super El Ninos, the researchers claim.
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Extremely warm sea surface temperatures are a notable feature of the super El Ninos that occurred in 1972, 1982, and 1997. The fact that Pacific Ocean processes responsible for generating regular El Ninos could not explain this key signature of super El Ninos came as a big shock,” says Dachao Jin, co-author of the study.
If you were to believe the mainstream media, you’d think our world is burning up. But that is not true.
Yes, there were places on our planet where it was warmer than normal today. But many parts of the world displayed normal or even colder than normal temperatures.
A new German paper assesses wind energy in Europe . The results are devastating. It concludes that wind energy requires almost 100% backup and that the more capacity that gets installed, the greater the volatility.
The paper appearing at the VGB, authored by Thomas Linnemann and Guido Vallana, finds that “the total wind fleet output of 18 European countries extending over several thousand kilometers in north-south and east-west direction is highly volatile and exhibits a strong intermittent character.”
In other words the power supply across the European grid fluctuates wildly and thus cannot work well. The paper’s abstract continues: …
According to the report, if we are to take cooling demand seriously, the key stages to move towards a solution for cooling demand are:
Reducing the energy required for cooling: getting industry to adopt high efficiency cooling technologies and using maintenance to deliver optimum performance.
Reducing the need for cooling through better building design
Systems level thinking across built environment and transport
Considering the strategies and skills required for installing appliances and maintaining them in order to maximise efficiency and reduce energy demand
Creating a model for delivery of affordable cooling to those in rural and urban communities based on the energy needs of local requirements, rather than imposing a ‘one size fits all’ approach
According to the Guardian (9 July 2018), there is a “global heat wave” going on right now.
In Siberia, the heat is supposedly “completely unprecedented” and will surely (we are told) impact Arctic sea ice — the habitat of the iconic polar bear. Yet a comparison of previous years shows little to no impact on sea ice: there is more ice present than there was in 2007.
Discovery provides evidence of iron-rich seawater much later than previously thought.
The banded iron formation, located in western China, has been conclusively dated as Cambrian in age. Approximately 527 million years old, this formation is young by comparison to the majority of discoveries to date. The deposition of banded iron formations, which began approximately 3.8 billion years ago, had long been thought to terminate before the beginning of the Cambrian Period at 540 million years ago.
The Early Cambrian is known for the rise of animals, so the level of oxygen in seawater should have been closer to near modern levels. “This is important as the availability of oxygen has long been thought to be a handbrake on the evolution of complex life, and one that should have been alleviated by the Early Cambrian,” says Leslie Robbins, a PhD candidate in Konhauser’s lab and a co-author on the paper.
Lately Arctic sea ice volume has been a topic which climate skeptics have been looking at quite closely.
According to Al Gore and a number of climate ambulance chasers, Arctic sea ice in late summer should have long disappeared by now, see here..
But then just a few years after, the Arctic sea ice area began to recover from its lows of 2007 and 2012. So immediately alarmists shouted that area was not really what mattered, but rather sea ice volume is what really counted. Okay, that made perfect sense. Mass is in fact what’s important, and not area, when worrying about polar ice disappearing …
How have we measured the temperature of the ocean’s upper layer in the last 150 years? How does understanding physical processes and observational errors help to standardise climate data and understand climate change?
Sea surface temperature (SST) is also one of the climate indices with the longest histories of direct measurements. Because ocean makes up about 70% of the total Earth’s surface, changes in the temperature of its surface are a key factor for determining the global temperature of the planet’s surface.
Summers in the U.S. are hot. They always have been. Some are hotter than others.
Speaking as a PhD meteorologist with 40 years experience, this week’s heat wave is nothing special.
But judging from the memo released on June 22 by Public Citizen (a $17 million per year liberal/progressive consumer rights advocacy grouporiginally formed by Ralph Nader in 1971 and heavily funded by Leftwing billionaire George Soros’s Open Society Foundations), every heat wave must now be viewed as a reminder of human-caused climate change. The memo opines that (believe it or not) the news media have not been very good about linking weather events to climate change, which is leading to complacency among the public.
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La géologie, une science plus que passionnante … et diverse
