- 2 days ago
Scientists trigger micro-quakes at the push of a button to understand how earthquakes start. Also: the environmental side of salt mining.
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00:08The Earth is a production of the U.S. Department of Health.
00:08Moving mountains at the push of a button.
00:13It might sound like science fiction, but in the Swiss Alps, it may soon become reality.
00:20In the Gotthardmassif, researchers at the University of Zurich hope to trigger a small earthquake.
00:26If it works, it could reveal more about how earthquakes start and whether they can be predicted.
00:36All this and more groundbreaking stories on DW's Science Show. Welcome to Tomorrow Today.
00:48The big moment is just days away.
00:50Researchers at ETH Zurich University are hoping to do something that's never been done in quite this way before.
00:57Deliberately triggering a small earthquake.
01:02But first, there's still plenty of work to do.
01:06A narrow road leads two and a half kilometers deep into the Gotthardmassif.
01:12The Bedretto tunnel underneath the mountain range is more than 50 years old and no longer in use.
01:18And now it's a perfect natural laboratory.
01:21Here, the team hopes to make an ancient fault deep inside the rock slip ever so slightly.
01:27We're here because of this fault zone. You can see the boundary here clearly. A thin line.
01:34In the middle, there's this very brittle material called fault gouge.
01:39That's evidence that the rock has slipped along this fault line before.
01:42This is where we're hoping to trigger a magnitude one earthquake.
01:51A magnitude one quake is tiny, far too small to be felt by humans at the surface.
01:57But it could reveal how earthquakes actually begin.
02:04We want to better understand the microphysics.
02:08What happens when an earthquake starts?
02:10How does the rupture propagate?
02:13Why does it continue and where and why does it stop?
02:16If we understand the underlying physics better, perhaps one day we'll be able to make better forecasts.
02:23Men Andrin Maia and his 70-member team have been planning and building this experiment for five years.
02:29They've installed more than 200 sensors inside the mountain, hoping to capture every moment of the earthquake as it unfolds.
02:39Here's how they plan to trigger it.
02:42The fault has slipped naturally before, producing tiny earthquakes.
02:50To reach it, the team has excavated a new tunnel branching off from the Budretto lab.
02:57From here, they'll pump water through three boreholes directly into the fault.
03:04As water pressure increases, the rock begins to shift.
03:08The existing stresses in the rock are released, triggering a micro-earthquake.
03:15Using six high-pressure pumps, they'll inject around 2,000 cubic meters of water into the boreholes to bring the
03:23fault to the point where it slips.
03:26The pump system operates at pressures approaching 200 bar, a demanding test for the equipment, and a potential hazard for
03:34anyone inside the tunnel.
03:37These are the anchoring systems.
03:40They're secured with chains and anchor pins in case the pressure becomes too high and part of the pipework comes
03:46loose.
03:49That could be quite dangerous because there's so much pressure behind it.
03:55We want to prevent damage to the equipment and avoid any injuries.
04:03The team checks every sensor and seismic instrument again and again.
04:11They want to make sure that all the data will stream live to the control room at ETH Zurich, where
04:17the experiment will be run.
04:20We're about to launch the first full-scale experiment. It's exciting.
04:27Two weeks later, the control room in Zurich.
04:30In just a few minutes, the test will begin.
04:37One last systems check at the Podretto lab, a hundred kilometers away.
04:45It's been a busy night and morning, but everything looks good and we're ready to go.
04:51The researchers are optimistic. The pumps are ready, and the safety systems are in place.
04:59So this button is to manually stop the pump.
05:03So we can press this button. Once we have it pressed for about eight seconds, the pumps in the tunnel
05:08will stop automatically.
05:09And this is a safety procedure that will allow to have a bit more control.
05:14The last members of the team have just left the tunnel.
05:17This is steam too, and that's pressure up by one megapascal.
05:23Here we go.
05:29The pumps are starting up, forcing water deep into the boreholes.
05:37The data stream to Zurich is running smoothly.
05:42Now comes the waiting game, watching the instruments and waiting for the fault to slip.
05:51Pressure inside the fault continues to rise, approaching 100 bar.
05:57Then, suddenly, a flood of new data appears.
06:02Deep inside the mountain, something has begun to move.
06:08We've already detected and located more than a thousand quakes since we started the simulation.
06:14They're almost certainly induced by us, given their number and size.
06:18We're doing this on purpose.
06:24After three hours, they've triggered more than 3,000 microquakes.
06:33Looking at it from above, you can see that these earthquakes line up along a plane that's roughly parallel to
06:38the tunnel.
06:42That's exactly the geological structure we were hoping to activate.
06:47It's working amazingly well.
06:49Now we just have to keep going, and hope we'll eventually reach magnitude 1.
06:57They didn't reach magnitude 1 this time, but the thousands of microquakes are already providing valuable clues about how earthquakes
07:05begin.
07:07Soon, they'll try again, hoping to make one tiny part of the Gotthard Massif slip.
07:13Just enough to trigger the mini-earthquake they've been waiting for.
07:22Deep beneath the Alps lies a resource prized for thousands of years.
07:29Salt.
07:31It's mined by pumping water underground, all cut directly from the rock.
07:37Often called white gold, its story began in Earth's ancient oceans.
07:43The story of this salt began 250 million years ago.
07:49Today, that salt lies deep underground.
07:53And we rely on salt in more ways than ever before.
07:57The seemingly humble mineral is one of the key raw materials of modern life.
08:04But table salt accounts for only a tiny fraction of its use.
08:09Most salt doesn't land on our plates.
08:13It's found in products we use every day.
08:16Without sodium chloride, many aspects of modern life simply wouldn't work.
08:21So how does such a simple substance become so incredibly versatile?
08:26The key lies in a chemical process that transforms it into three essential chemical building blocks.
08:33Chlorine is used to make plastics like PVC, medications, a wide range of chemical products, and to disinfect drinking water.
08:43Caustic soda is used to produce aluminum, paper and textiles, and much more.
08:51Hydrogen is a by-product used mainly in industry, and increasingly as an energy carrier.
09:01One raw material, countless products.
09:07In Germany, salt is an important natural resource.
09:10And the country produces an average of 18 million tons of salt every year.
09:17Most of domestic demand is met from these deposits, and large amounts of salt are exported every year.
09:28Today's salt deposits formed many millions of years ago.
09:33Back then, a shallow sea covered large parts of Central Europe.
09:40Shifting tectonic plates created isolated seas and salt lakes.
09:45As the water evaporated into the hot, arid climate, the dissolved salts crystallized.
09:51Eventually, layers of salt were buried under sediment and younger rock, over and over again.
09:58Today, salt deposits in the form of sodium chloride stretch beneath northern and central Germany.
10:04It's mined and then processed.
10:06But not all salt is the same.
10:09Sodium chloride is only part of the story.
10:12There are also potassium-rich salts, the most important raw material for a potash fertilizer.
10:19But it's not pure.
10:20Much of the ore consists of rock salt and other minerals that must be processed and separated.
10:28These deposits are concentrated in central Germany.
10:33Potassium is an essential nutrient for plants.
10:36That's why potash salts are used around the world to make fertilizers.
10:42Potash salts dissolve in the soil, releasing potassium that helps plants use water efficiently,
10:48and also resist drought, frost, and disease.
10:52And that, in turn, increases the quantity and quality of the harvest.
11:00But potash mining also has a downside.
11:04Only part of the ore is used, while huge quantities remain as solid and liquid residues.
11:11Over the decades, huge waste heaps have built up at some mining sites.
11:18The K&S Mining Company, for example, extracts up to 40 million tons of potassium-rich ore a year.
11:26After processing, that becomes just 9.5 million tons of marketable products.
11:32Most of the mined material ends up as waste.
11:36At just one site in central Germany, hundreds of millions of tons of residue are stored in towering heaps,
11:43with official approval.
11:45Rain washes salt from those heaps, creating waste water that's discharged into the Werra River.
11:52Liquid processing residues also end up there.
11:56Salt is a raw material essential to much of modern life.
12:00It helps power our world and reshape it.
12:04The question is, at what cost?
12:13This river has a problem.
12:15And you can measure it.
12:19Biologist André Busch and his colleagues are searching for life in the Werra.
12:26For decades, environmental authorities have been tracking salt levels here,
12:30and what they're doing to the plants and animals that depend on this river.
12:36Under the EU Water Framework Directive, rivers are graded on a five-point scale.
12:40Here at Gerstungen, the Werra is currently rated as being in poor environmental condition.
12:48One of the biggest reasons is salt.
12:50For decades, potash mining has discharged saline water into the river.
12:55The result is salt levels more than 20 times higher than in a healthy river.
13:01Many of the species you'd expect to find in freshwater have disappeared.
13:08The species here are highly salt-tolerant.
13:12Many also occur in the brackish waters off the North Sea and Baltic region,
13:16and some even in the seas themselves.
13:19We have the tiger scud and the invasive New Zealand mud snail here, for example.
13:24We also have water milfoil and gutweed.
13:27Their abundance is another clear sign of the river's high salt content.
13:34By now, things should be different.
13:36Under EU rules, rivers and lakes are supposed to be in good condition by 2027.
13:43That's essential for clean drinking water and healthy ecosystems.
13:53Further upstream, which isn't affected by the saline discharges, it's a different story.
14:01We've found about 70 species here in the unpolluted section of the Wehre,
14:05including important ones like mayflies, caddisflies and stoneflies,
14:09which are key indicators for the EU guidelines.
14:13Their presence is a sign of a healthy river.
14:16It's a glimpse of what the Wehre could become if salt levels were much lower.
14:25Further downstream, though, the discharges are set to continue.
14:29The K&S mining company has long faced criticism over the pollution,
14:33but says it's working to reduce its environmental impact.
14:39One major project is a more environmentally friendly processing system,
14:43designed to eliminate liquid production waste.
14:47K&S declined our request for an interview.
14:50In a written statement, the company said,
14:54When disposing of solid residues,
14:56we are also continuously minimizing our environmental impact
15:00and using state-of-the-art technology.
15:07The company's main solution is covering the waste heaps.
15:10Layers of plastic liner, soil and vegetation are designed to keep rainwater out,
15:16preventing salt from entering the river.
15:19But critics question whether it will work in the long run.
15:25Reducing the river's salt pollution is technically difficult and expensive,
15:29and the company says the problem can't be eliminated completely.
15:34The authorities have repeatedly renewed the discharge permits,
15:37although with progressively tighter limits.
15:42Salt levels in the Wehre have fallen,
15:44but the river still has a long way to go.
15:51Salt can also have healing properties.
15:54Salt brine has been used in spas for centuries.
16:00Now it's helping to grow sea lettuce,
16:03bringing a taste of the sea closer to home.
16:08Forget garden lettuce.
16:10Sea lettuce could be the food of the future.
16:12And it's now being grown beneath the spa in Bad Saro, in eastern Germany.
16:18This is edible lettuce, our Ulwe Compressa,
16:21originally collected near the island of Heligoland.
16:23We collected it there in 2019, isolated it, and over the years developed cultivars that are now thriving here in
16:30the brine.
16:33Anna Fricke has spent 20 years researching algae.
16:36For the past three, she's been growing sea lettuce in the spa's basement.
16:45One big advantage of algae is that they don't need fresh water.
16:49They grow in seawater, or even here in brine, so they don't depend on our drinking water.
16:55That's a huge difference from lettuce, which needs regular watering.
17:02Scientists and entrepreneurs have gathered in one of the spa's conference rooms to talk all things algae.
17:10Algae are incredibly versatile, not just in cooking, but in all kinds of different fields.
17:15They have something to offer for almost every application, from food supplements to cosmetics.
17:21In other words, algae have real commercial promise, and perhaps even more.
17:27Algae can be a key part of protecting our planet, if we're serious about doing that.
17:33Algae sommelier Oliver Skoluta is showing participants just how tasty they can be.
17:42We start with a fresh take on a classic German dish, Königsberger Klopse.
17:47Instead of parsley, I use sea lettuce.
17:50It's an easy way to bring algae into a traditional favourite.
17:55The dishes are vegan, and of course made with algae.
17:59So, what's the verdict?
18:01I like it, it has a little taste of the sea.
18:04For now, algae farming here is still being tested.
18:07But researchers hope to scale it up over the next few years.
18:14Our goal is to develop products people can use here on site, or take home with them.
18:23Anna Flickes says algae have plenty going for them.
18:26They can be cultivated sustainably and are rich in vitamins and proteins.
18:31But if you've never eaten algae before, your microbiome needs time to adapt.
18:37So you should introduce them gradually and get used to them step by step.
18:44It's still early days.
18:45But before long, superfood algae from Bad Saro could be on the menu.
18:52What are stars made of?
18:55How many colours can butterflies see?
18:58Could robots have babies one day?
19:01Do you have a science question?
19:03Then send it to us as a video, text or voice message.
19:07If we answer it in the show, then we'll send you a little gift as a thank you.
19:11So, just ask.
19:17Algae is often called the superfood of the future.
19:20It also contains iodine, a trace element our thyroid gland needs to function.
19:26But in Germany and many other countries, millions of people still don't get enough iodine.
19:31And here too, salt can be part of the solution.
19:37Around one in three people in Germany may not be getting enough iodine, often without realising it.
19:44Experts have been warning about the problem for years.
19:46Jochen Fedkamp is a doctor who's campaigning to improve iodine intake in Germany.
19:53The situation has worsened because of lower iodized salt consumption.
19:57The main problem is the food industry, which still relies mostly on ordinary salt.
20:02As a result, we're getting less iodine from our food.
20:06We've now reached the point where Germany once again meets the WHO criteria for iodine deficiency.
20:14Both West and East Germany began using iodized salt much more widely in the 1980s.
20:20By then, scientists already understood how important iodine is for health.
20:26Iodine is a trace element we need to get from food.
20:30The thyroid gland uses it to produce the hormones T3 and T4, which act on almost every cell in the
20:37body.
20:43These hormones help regulate the cardiovascular system and blood pressure, and support cell growth and development.
20:50That's why they're important for healthy bones and for the development of the brain and nervous system.
20:57They also help regulate metabolism, which influences body weight.
21:02Too little iodine over time can lead to health problems.
21:07Radiologist Melva Abel often sees thyroid nodules in her patients.
21:11Long-term iodine deficiency can be one factor in their development.
21:16The thyroid can enlarge, and that may contribute to nodules developing over time.
21:23Large nodules can cause swallowing problems or shortness of breath.
21:27And in some cases, a thyroid nodule may become cancerous.
21:35Treatment depends on the type of nodule, not just its size.
21:39Some only need monitoring.
21:41Others may require medication, radioiodine treatment or surgery.
21:48Mild iodine deficiency often goes unnoticed.
21:50But if the thyroid can no longer produce enough hormones, symptoms may include feeling cold, dry skin, hair loss, weight
22:00gain, as well as low mood and problems with memory and concentration.
22:05Over the long term, an iodine deficiency can cause what's known as a goiter.
22:10For adults, the WHO recommends a daily intake of 150 micrograms.
22:18Five grams of iodized salt provides roughly 100 micrograms.
22:22But most people in Germany consume only about one gram of iodized salt a day.
22:31We shouldn't eat too much salt, of course. It can raise blood pressure.
22:35But when we do use salt, it should be iodized.
22:39One of our goals is to make sure more of the salt people consume is iodized.
22:50Most of us consume too much salt.
22:52Much of it comes from processed foods, such as bread, cold cuts in cheese, and seasoning mixes.
23:00But manufacturers usually use ordinary salt rather than iodized salt.
23:05Cost is one reason.
23:07So we may be eating plenty of salt but still not getting enough iodine.
23:12Nutrition specialist Constanza Lohse says cooking more meals from scratch can help.
23:17Cook at home and eat mainly fresh, minimally processed foods rather than fast food or ready-made meals.
23:23And use iodized salt.
23:26Normal amounts of iodized salt are generally also safe for people with Hashimoto's thyroiditis.
23:35Using iodized table salt is generally okay for Hashimoto's.
23:39It doesn't make the condition worse.
23:41And the whole family benefits from consuming iodized salt.
23:46One more tip.
23:48Unfortified sea salt, Himalayan salt, and many specialty salts contain very little iodine.
23:54A diet based mainly on fresh, unprocessed foods provides about 120 micrograms of iodine a day.
24:01Fish and seaweed are naturally rich sources of iodine.
24:05But in Germany, most people don't eat them regularly.
24:09Milk, dairy products and eggs also provide small amounts, partly because iodine is added to animal feed.
24:17Fruit and vegetables generally contain very little.
24:20In much of Germany, the soil is naturally low in iodine.
24:25Another issue is dietary trends.
24:28That includes vegan diets and other eating patterns that exclude certain food groups, especially iodine-rich foods such as fatty
24:36fish.
24:39People at risk of iodine deficiency may benefit from an iodine supplement.
24:44Some experts in Germany recommend up to 100 micrograms daily.
24:49It's not a medication. It's a dietary supplement to maintain your health.
24:54And it's considered safe.
24:57Adequate iodine is especially important during pregnancy for the healthy development of the baby.
25:04Severe iodine deficiency during pregnancy and breastfeeding can cause lasting developmental problems.
25:10Even a mild deficiency may affect a child's brain development.
25:16Studies suggest that children who received too little iodine in the womb may later do less well in areas such
25:22as reading comprehension.
25:25Some studies have also found slightly lower IQ scores.
25:29That's why adequate iodine is important for the developing brain.
25:35And for many people, iodized salt is still the simplest way to get more iodine.
25:45That wraps things up this time around.
25:47Thanks for joining us and hope to see you next time on Tomorrow Today.
25:51Bye for now!
26:05Bye for now!
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