Planet Earth

Giant mountains discovered inside the Earth

Studying the boundary between the Earth’s core and mantle, geophysicists have found that it is not as smooth as previously thought. Surfaces separating the inner layers also have a complex relief. It turns out that our planet is not at all like a set of spheres nested into each other, as is customary to portray it.

Reading the waves. Earth’s crust

The deep bowels of geophysics are judged by seismic waves generated by earthquakes. There are longitudinal P-waves – when elastic mechanical vibrations occur along the propagation direction and transverse S-waves – the vibrations in them are perpendicular.At the boundary of layers with different densities, the wave velocity changes dramatically. In the transition from a solid crust to a more plastic upper mantle, it increases. This border is called the surface of Mokhorovichich. The lower mantle is harder than the upper. The outer core, in which transverse seismic waves do not propagate, is liquid, and the inner core is again solid, but slightly plastic.

While the network of seismographs was rare, the sections between the inner shells with a certain degree of conventionality were depicted as spheres. As the data accumulated, it became clear that each of these boundaries is a complex surface with its relief and internal “mountains” even higher than on the Earth’s surface, and the “troughs” are deeper. From the top of Everest to the bottom of the Mariana Trench about 20 kilometers, and, for example, the differences of the border of Mokhorovichich, dividing the crust and upper mantle, reach 40 kilometers. And all this at a depth of five to 70 kilometers.

This was proved by scientists from China and the United States . They analyzed the results of observations of hundreds of seismic stations obtained from the same events: the earthquakes in Bolivia of 1994 and the Sea of Okhotsk in 2008 and 2012, as well as archival records of seismographs of the National Center for Information on Earthquakes of the US Geological Survey.

The authors of the study found that for the boundary between the upper and lower mantle, located at a depth of about 660-670 kilometers, the data of the various stations almost completely coincide. That is, she has a stable relief, which she even managed to map. Signal processing of the Bolivian earthquake made it possible to literally create a “topographic map” of the surface of the lower mantle for an entire region in Southeast Asia .

The most dynamic area. Mantle and core

When talking about the dynamics of the Earth, they usually mean large-scale surface processes associated with the movement of lithospheric plates. In the zones of mid-ocean ridges and rifts, the lithosphere moves apart, and in subduction zones on the outskirts of the continents, oceanic plates sink under the continental.

But no less dynamic processes and surface movements occur inside the Earth – only their reflection. First of all, we are talking about mantle convection, which arises due to the temperature difference in the bowels and on the surface of the planet.

Upward flows of convection cells stretch the lithosphere, downward flows drag it into the mantle. Moreover, in the upper parts of the cells, the substance flows in a horizontal plane and these flows cause lithospheric plates to move.The most dynamic region of the Earth is located on the border of the core and mantle, at a depth of about 2900 kilometers.

It is believed that its heterogeneity affects many geological processes, in particular, the oscillation of the axis of rotation of the Earth and the characteristics of the geomagnetic field. In addition, convection itself is a consequence of what happens in the D ”layer at the boundary with the core.On its surface, scientists discovered arrays of unusually dense, hot rocks – zones of abnormally low seismic wave velocities (ULVZ – Ultra-low velocity zones). They stretch for hundreds of kilometers, and their “height” – tens of kilometers.Above them are hot spots with volcanoes: Hawaiian, Marquesas, Galapagos Islands and the Samoa archipelago in the Pacific Ocean, Canary Islands and Azores , Iceland in the Atlantic, Kerguelen archipelago in the Indian, Afar volcanism zone in the Great African Rift.

Using the new machine learning algorithm, American scientists at Johns Hopkins University and the University of Maryland at College Park together with their Israeli colleagues from Tel Aviv University performed a parallel analysis of seven thousand seismograms covering hundreds of earthquakes from 1990 to 2018, and for the first time compiled a detailed section map the core and mantle of the Pacific region, on which all ULVZ zones were applied.It turned out that ULVZ are only separate protrusions within the larger, low-shear-velocity provinces (LLSVP) provinces, which are also called superplumes. Their branches penetrate up into the mantle for thousands of kilometers. Now scientists distinguish two such provinces – African and Pacific.

Superplumes (provinces with a low shear rate) at the boundary of the core and mantle look like they look from the North (a) and South (b) poles. The center shows the core of the Earth with the projection onto it of the contours of the continents; outer contour - conditional border of the lower mantle — © Sanne Cottaar, Vedran Lekic / Geophysical Journal International, 2016Superplumes (provinces with a low shear rate) at the boundary of the core and mantle look like they look from the North (a) and South (b) poles. The center shows the core of the Earth with the projection onto it of the contours of the continents; outer contour – conditional border of the lower mantle

The circulation of matter in the mantle

Australian scientists from the University of Curtin suggested that the periods when all the land of the Earth united into single supercontinents – Pangea, Rodinia, Colombia and others, coincided with activity in the deep LLSVP provinces. They built a dynamic model linking the evolution of superplumes to the assembly and decay of supercontinent. According to this model, LLSVP arrays are formed from lithospheric plates, which, as it turned out, sinking, does not dissolve in the mantle, as previously thought, but descend to the very boundary of the core. Here they melt, and giant drops of preheated matter – mantle plumes – coming off from LLSVP, float to the surface, giving rise to a new geodynamic cycle. The lithosphere rises above the plumes, forming a dome, and then cracks and diverges.

Inside the core

Researchers from the US and China have analyzed how seismic waves passing through the boundary between the outer and inner core change. For this, we used signals from doublets – repeated earthquakes with the same epicenter.

It turned out that these changes have a certain periodicity, which can be explained by two mechanisms: either the inner core rotates by about 0.05-0.1 degrees per year, or high “mountains” and deep “canyons” appear on its surface. So, a dynamically changing relief can also be at the deepest boundary between the earth’s shells.

Planet Earth

Alvin Toffler: Rural bioconverters as an alternative to urbanism

The great American futurologist Alvin Toffler gives a chance to the countryside. His prediction is that the countryside will be covered by a network of “bioconverters” where biomass waste is converted into food, feed, fiber, bioplastics and other goods.

The US domestic bioeconomy will be able to meet 90% of the country’s need for organic chemical fertilizers and 50% – the need for liquid fuel. Every million liters of bioethanol produced creates 38 direct jobs. Therefore, jobs are formed not “at the oil pipe”, but in agricultural regions.

American philosopher and futurologist Alvin Toffler and his wife Heidi Toffler published the book “Revolutionary Wealth” in 2006. There was no Internet power yet, the heyday of alternative energy and robots, but Toffler was already looking beyond the horizon of our time. For example, he not only draws attention to the fact that “time has become denser” (the same processes a hundred years ago and today are proceeding at different speeds), but that traditional institutions – family and education, bureaucracy and political parties – are increasingly lagging behind the growth rate production, from new values, communications and from the process of globalization. And in this discrepancy between the old institutions and processes of the new time lies the source of the impending crisis.

In the preface to the Toffler’s book, he writes:

“Wealth does not arise only in fields, factories, and offices. Revolutionary wealth is associated not only with money. Currently, even the most stupid observers cannot help but see that the economy of the United States and several other countries is transforming, turning into an intelligent economy controlled by the mind. The full impact of this transformation on the fate of an individual, as well as on the fate of all countries and even continents, has yet to be felt. The past half century has been only a prologue to this transformation.”

Nevertheless, Tofflers in their book also pay attention to the transformation of old institutions – for example, rural production, assuming that, having transformed, it will give people an alternative way of life from the city. We provide an excerpt from the book “Revolutionary wealth” about the new life of the countryside.

“In a stunning document that was not given due attention, the Center for Technology and National Security Policy at the University of Washington National Defense paints a picture of the world where” agricultural fields will have the same meaning as oil fields.”

Even oil company managers have spoken about the “last days of the oil century.” Dr. Robert Armstrong, author of a report by the University of National Defense, develops this idea by claiming that we are moving towards a biology-based economy, where “gas will be replaced by genes” as a key source of not only various raw materials, but also energy.

At the beginning of the XXI century, American farmers produced 280 million tons of unnecessary leaves, stems and other plant waste per year. Some of this material is already being used, turning into chemicals, electricity, lubricants, plastic, adhesives and, most importantly, into fuel. This, however, is only the beginning. Armstrong anticipates that the countryside will be covered by a network of “bioconverters,” where biomass waste is converted into food, feed, fiber, bioplastics, and other products. He quotes from the 1999 report of the National Research Committee, which states that the US domestic bio-economy “will be able to satisfy 90% of the country’s need for organic chemical fertilizers and 50% of the need for liquid fuel.”

And this applies not only to America. In such an economy, Armstrong continues, “genes will be the basic raw materials, and they can be found everywhere, unlike oil.” Thus, he predicts a gigantic geopolitical shift in power from desert oil powers to tropical regions characterized by a rich and diverse biosphere.

“In the world of biotechnology,” Armstrong writes, “our relationship with Ecuador (a representative country) will become more significant than our relationship with Saudi Arabia.” Reason: Ecuador has a much greater diversity of the biosphere, and therefore – a variety of genes that have potential value for the whole world. If this is true in the case of Ecuador, what about Brazil? Or Central Africa?

The Eden project in Cornwall, England, launched by Tim Smith, is the largest greenhouse in the world. Smith believes that “we are on the eve of the greatest revolution. From plant materials we can produce composite materials that are more durable than steel and Kevlar. The possibilities for its use are phenomenal. Every country in the world can possess modern materials derived from its own plants.”

Alvin Toffler: Rural bioconverters as an alternative to urbanism 91

Eden Project in Cornwall

Moreover, Smith continues, “bioconverters should be built close to sources of raw materials. It is likely that regional agricultural crops will be actively developed, and special crops will be grown in certain regions to supply local bioconverters. The result of this process will be the creation of non-agricultural jobs in agricultural areas.”

Armstrong concludes:

“An economy based on biotechnology can ultimately stop the process of urbanization.”

North America plans to plant empty fields with Miscanthus, a giant elephant grass. Studies show that from one hectare it is possible to obtain by burning such an amount of fuel that is enough to replace 40 barrels of oil.

An example of Russia

In Russia, it is technically possible now every year to use about 800 million tons of wood biomass, which is not currently used in timber harvesting, and about 400 million tons of dry matter of organic waste, and 250 million tons of them of agricultural origin , 70 million tons of forestry and woodworking industry, 10 million tons of wood and hardwood waste (collected annually in cities), 60 million tons of municipal solid waste (mainly pulp and paper products and plastics) and 10 million tons other waste (for example, precipitation of municipal drains, etc.). Their processing potentially allows you to get 350-400 million tons of oil equivalent per year and open up to 500 thousand new jobs.

US example

Every million liters of bioethanol produced creates 38 direct jobs. Therefore, jobs are formed not “at the oil pipe”, but in agricultural regions. The raw materials for most bioeconomic products are sugar (glucose), starch (sugarcane) or cellulose (straw, sawdust). One of the most modern bio plants is the Dupont plant, which produces 100 thousand tons of corn bioplastics per year. This bioplastics surpasses nylon in cost price and consumer qualities.

Planet Earth

Silvery clouds alerted scientists

In summer, in the night sky, you can see something truly magical, namely silver clouds or mesospheric clouds. This rare phenomenon got its name because of the flickering effect in the twilight sky. However, despite its beauty ,these clouds can be a wake-up call.

Silvery clouds form in the mesosphere – a rarefied upper atmosphere with a small amount of moisture and low temperatures at an average height of 82 kilometers. The nature of this phenomenon has not been fully studied, however, scientists suggest that clouds form due to scarce water vapor, which freezes, creating crystals. Since the mesosphere is the coldest in summer, such clouds are observed precisely in this season.

The reason this phenomenon is not well understood is that the history of these clouds is relatively young. For the first time they were reported in 1885, and immediately scientists began to talk about the fact that they could appear due to climatic changes.

Now experts are again considering this possible reason, since for many years these clouds were mainly found only in the polar regions. But lately they have been laid much further, and look much brighter. So, on June 21, residents of the UK watched this beautiful phenomenon, although it is quite unusual for these places.

Most of the moisture needed to form clouds comes from methane – a greenhouse gas – that produces water vapor when it is destroyed in the upper atmosphere. And as methane pollution increased, silvery clouds became brighter, and most importantly, noticeable in new places.

Silvery clouds are studied by scientists, both from the Earth and from space, since they are quite high. However, to understand the true cause of the phenomenon, specialists still have a lot of work to do.

Planet Earth

A clear comparison of all the plastic in the world with New York

A modern person has a huge number of reasons for constant concern. And one of the most pressing concerns is plastic, which is about to evict us from our home planet.

Graphic craftsmen from the MetaBallStudios Youtube channel, specializing in visual comparisons of various things, decided to team up with the anti-plastic organization BeyondPlastic.net and create not just entertaining video, but entertaining and informative. It turned out, in our opinion, a real mini-horror movie.

Here’s what it took to create a horror movie: count all the volumes of plastic, put them together in black bags and compare with the city of New York. The video shares the following information with us:

on average, every inhabitant of Europe and America spends 100 kg of plastic annually (if you remember that plastic weighs almost nothing, it becomes uncomfortable);
daily in New York (substitute any city with a population of 9 million people) spent 2,300 tons of plastic;
30 thousand tons of disposable coffee cups are thrown around the world every day;
840 thousand tons of plastic are thrown out in New York annually;
in 1950, the global consumption of plastic was 1.5 million tons;
and today, up to 8 million tons of plastic are thrown into the ocean;
58 million tons of plastic bottles are produced worldwide annually;
and plastic bags altogether 100 million tons;

Perhaps, we will stop at this terrible figure – watch the video and understand everything yourself. We urge you to be responsible for nature.

Try to go to the store with a reusable bag, start with a reusable mug if you buy take-away coffee and generally think about the planet. Alas, we have nothing for life better than the Earth. This is proven.