Everything Everywhere Daily: History, Science, Geography & More - All About Sand

Episode Date: December 15, 2024

One of the most common substances on Earth is sand.  Most people don’t think very much about sand, but sand is an extremely important part of our world.  It isn’t just for building sand castles ...and going to the beach. Sand is the second most consumed resource in the world after water.  There is an entire science to sand, what different types consist of, how it is made, and even how it moves.  Learn more about sand and the surprising complexity of a seemingly simple subject on this episode of Everything Everywhere Daily. Sponsors Mint Mobile Cut your wireless bill to 15 bucks a month at mintmobile.com/eed MasterClass Get up to 50% off at MASTERCLASS.COM/EVERYWHERE Quince Go to quince.com/daily for 365-day returns, plus free shipping on your order! ButcherBox New users that sign up for ButcherBox will receive 2lbs of grass fed ground beef in every box for the lifetime of their subscription + $20 off your first box when you use code daily at checkout! Subscribe to the podcast!  https://everything-everywhere.com/everything-everywhere-daily-podcast/ -------------------------------- Executive Producer: Charles Daniel Associate Producers: Ben Long & Cameron Kieffer   Become a supporter on Patreon: https://www.patreon.com/everythingeverywhere Update your podcast app at newpodcastapps.com Discord Server: https://discord.gg/UkRUJFh Instagram: https://www.instagram.com/everythingeverywhere/ Facebook Group: https://www.facebook.com/groups/everythingeverywheredaily Twitter: https://twitter.com/everywheretrip Website: https://everything-everywhere.com/  Learn more about your ad choices. Visit megaphone.fm/adchoices

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Starting point is 00:00:00 One of the most common substances on earth is sand. Most people don't think a whole lot about sand, but sand is an extremely important part of our world. It isn't just for building sand castles and going to the beach. Sand is the second most consumed resource in the world after water. There is an entire science to sand, what different types consist of, how it's made, and even how it moves. Learn more about sand and the surprising complexity of a seemingly simple subject on this episode of everything everywhere daily. What if your perceptions about the past were wrong?
Starting point is 00:00:47 ThruLine is a podcast that takes you back in time to uncover the parts of the story that may have gone unnoticed. It effectively turned day into night. And how it shaped the world now. Time travel with us every week on the ThruLine podcast from NPR. Let's start out with the basics and answer the question, What is Sand? We all know when we see it, but how is it actually defined?
Starting point is 00:01:20 Sand isn't a substance per se. There isn't one type of sand. Sand is a term that covers a wide variety of sedimentary particles of a given size. To understand how sand is classified, it's important to understand the Wentworth Scale. The Wentworth Scale and its modification known as the Crumbine Phi Scale is a widely used system for classifying sedimentary particles based on their size. It was developed by an American geologist Chester K. Wentworth in 1922 as a modification of earlier systems to provide a standardized framework for describing grain sizes in sediments and sedimentary rocks.
Starting point is 00:01:58 The Wentworth scale covers every sort of particle from the very large to the very small. Anything with a diameter greater than 256 millimeters is considered to be a boulder. Anything between 64 and 256 millimeters is called cobble. and this would be about the size of a river stone you might use for skipping rocks. Anything from 2 to 64 millimeters are considered pebbles. And finally, anything from 0.0625 to 2 millimeters is sand. And below sand on the scale is silt and clay. Sand can further be subdivided into very coarse, coarse, medium, fine, and very fine sand.
Starting point is 00:02:43 and that is all that sand is. Any rock or mineral that has a diameter between 0.0625 and 2 millimeters is sand. Sand and other sedimentary particles are created through a series of natural processes that break down larger rocks and minerals into smaller fragments. This process begins with weathering, the breaking down of rocks at or near the Earth's surface. Weathering occurs in three main forms, physical, chemical, and biological. Physical weathering involves mechanical forces such as the expansion of water when it freezes in rock cracks, causing the rock to fracture or abrasion, where rocks grind against each other due to wind, water, or ice. Over time, these actions produce smaller and smaller particles.
Starting point is 00:03:34 Chemical weathering transforms rocks by altering their mineral composition through reactions with water, oxygen or other chemicals. For example, hydrolysis occurs when water reacts with minerals like Feldspar, converting them into clay and soluble compounds. Similarly, oxidation causes iron-rich minerals to form rust-like substances breaking down the rock. Biological weathering, the third type, occurs when organisms such as plants and lichens physically break apart rocks or chemically alter them by secreting acids. Once the rocks are broken down into smaller pieces, Erosion removes these particles from their original location. Erosion is driven by forces such as water, wind, ice, and gravity.
Starting point is 00:04:17 Erosion is different from weathering in that it involves the movement of particles, whereas weathering does not. For example, flowing rivers and streams carry sediment downstream, while wind transports fine particles like sand and silt across deserts. Glaciers, moving massive sheets of ice, scrape and grind the underline rock, transporting the resulting particles far from their source. Waves can also move and erode sand along shores and coastal areas. The important thing to understand is that the process of weathering and erosion is going to be different for every collection of sand depending on where in the world you find it. While any rock or mineral of the right size can be considered sand, there are some types of sand that are very common all over the world. And the most common mineral that winds up as sand is quartz. Quartz is the most common mineral in sand due to its
Starting point is 00:05:08 abundance in the earth's crust and its resistance to weathering. Quartz is a very hard mineral. It's a seven on the Mo's hardness scale, which makes it much harder and much more difficult to erode than most other minerals. You'll usually find quartz sand where you find continental crust. Quartz sands are frequently found on beaches, particularly in regions with extensive weathering of continental rocks like granite. The high energy of waves and currents often remove lighter or softer minerals, concentrating the durable quartz grains. Most deserts contain a high amount of quartz. The Sahara Desert contains areas with significant quartz sand, as does the Namib Desert in Africa,
Starting point is 00:05:48 for example. White sand beaches like those in Siesta Key, Florida, or Whitehaven Beach in Queensland, Australia, are famous for their nearly pure quartz sand, which is also known as silica. Fraser Island in Australia is known for some of the purest quartz sand dunes in the world. However, not all white sand beaches are made out of quartz. If you go to a tropical island, you may see a white sand beach, and these beaches are almost never made out of quartz. They're made out of calcium carbonate, which is also white.
Starting point is 00:06:20 This type of sand primarily originates from biological processes and the breakdown of marine organisms. Coral, seashells, and plankton exoskeletons are all made out of calcium carbonate. When these organisms die, their shells and skeletons break apart due to wave action, predators, or decay. And over time, the fragments are ground into finer particles forming sand. There are also other types of white sand. White sands National Park in New Mexico has sand made out of gypsum, which is also white. This type of sand is very rare and only found where you have exposed gypsum deposits.
Starting point is 00:06:58 Other types of rare sands can be found all over the world as well. Black sand can be found in places with active volcanism. This comes from the erosion of black volcanic basalt rock. There are black sand beaches that can be found in Hawaii, the Canary Islands, Italy, Bali, French Polynesia, and many other places. There are four places in the world where you can find green sand, the most famous of which is the green sand beach on the big island of Hawaii. There are also green sand beaches in Guam, Ecuador, and Norway. The green sand comes from the mineral olivine. Olivine is very common in the earth's mantle, but much rare on the surface.
Starting point is 00:07:38 It comes to the surface through volcanoes. The green sand beach in Hawaii is the remnants of a cinder cone with a high level of olivine. And there's also an amber variant of olivine, which can be found with the green, but the green is what it's famous for. On the island of Maui, there's a red sand beach that can be found not far from the town of Hanna. The red is rust that comes from the iron-rich basalt found nearby. If the iron content was less, the beach would be black instead of red. Pink sand beaches are rare coastal areas where the sand has a distinct pinkish hue. The color comes primarily from tiny fragments of pheraminaifera,
Starting point is 00:08:16 which are marine organisms with reddish pink shells made of calcium carbonate. These shell fragments mix with standard sand particles, often alongside crushed coral and other marine debris, creating the soft pink coloration. These beaches are typically found in tropical regions near coral reefs, such as the Bahamas and Bermuda. As you are well aware, sand can form dunes. Dunes have unique properties that are probably worth an episode of their own at some point.
Starting point is 00:08:43 Dunes are not static formations. They are always slowly moving as winds blow sand. They can sometimes move as much as several meters a year, and over centuries they can change completely. Singing sand dunes, also known as booming dunes, are a natural phenomenon where sand emits a deep, resonant hum or booming sound when it moves. This occurs when large amounts of dry, well-sorted sand grains slide down the steep slopes of a dune under specific conditions. The sound is caused by the friction between the sand grains, creating vibrations that resonate through the dune. The pitch and tone of the sound depends on factors such as the size and shape of the grains, moisture content, and the speed of the,
Starting point is 00:09:26 of movement. Singing dunes are rare and can be found in deserts around the world, including the Sahara, Gobi, and Nabib deserts. As I mentioned in the introduction, sand is the world's second most used natural resource behind water. However, most of us don't really think of sand as a resource. Nonetheless, it's used for a wide variety of purposes. High purity silica sand is melted to create glass for windows, bottles, and screens. Likewise, silica sand is used to manufacture optical fiber, for telecommunications. Ultra-pure quartz sand is refined to extract silicon, a critical material and semiconductors for electronics like computers and smartphones. Sand is used in making tiles, pottery, and other ceramic products. Foundries use sand molds to shape molten metal into precise forms.
Starting point is 00:10:16 Sand is also a natural filter used in water purification systems and aquifers. The single largest use for sand, however, is in the construction industry. Sand plays a critical role in construction as a primary ingredient in essential building materials, such as concrete, mortar, and asphalt. In concrete, sand is combined with cement and gravel to form a durable, versatile material used in construction projects, bridges, roads, and dams. Mortar, a mix of sand and cement, binds, bricks, stones, and other materials in masonry. Sand also provides bulk and strength to construction materials improving their structural stability. Additionally, it's used as a base material in road construction, as a filling material in land reclamation, and as a leveling agent
Starting point is 00:11:01 beneath foundations and pavements. However, there is a problem with the construction industry's use of sand. We're running out of it. Now, this might seem absurd at first because we have deserts full of sand. It's almost like saying we're running out of seawater. Nonetheless, we are running out of sand because you can't just use any old sand for construction, especially for creating concrete. Desert sand is not suitable for construction because its grains are too smooth and rounded, a result of wind erosion that polishes the particles over time. These smooth grains lack the angular edges needed to create strong mechanical bonds with cement and concrete, leading to weaker structures. Additionally, desert sand is often too fine and uniform.
Starting point is 00:11:51 in size, which prevents it from achieving the proper density and stability required for construction materials. In contrast, river or quarry sand has angular grains and a mix of particle sizes, making it ideal for creating durable and strong concrete and mortar. The construction boom, particularly in fast-grine economies like India and China, has created immense demand for sand. Most of the sand used for construction comes from sand mining, usually on beaches and riverbeds. However, However, easily accessible sources of the right kind of sand are running out. And this has resulted in a surge in illegal sand mining. And it's become a big business for organized crime.
Starting point is 00:12:35 These criminal networks, often referred to as sand mafias, operate in countries like India, Kenya, and Cambodia, where they exploit poorly regulated or protected areas such as riverbeds, beaches, and coastal zones. They extract sand in large quantities, bypassing environmental laws, and not paying taxes. Their operations frequently involve violence, intimidation, and corruption, targeting activists, journalists, and officials who oppose illegal sand mining. Sand can be found almost everywhere around the world, albeit in very different forms.
Starting point is 00:13:08 It plays a vital role in everything from geology to biology to industry, and even, it appears, organized crime. The executive producer of Everything Everywhere Daily is Charles Daniel. The associate producers are Benji Long and Cameron Kiever. I want to give a big shout out to everyone who supports the show over on Patreon, including the show's producers. Your support helps me put out a show every single day. And also, Patreon is currently the only place where Everything Everywhere or daily merchandise
Starting point is 00:13:40 is available to the top tier of supporters. If you'd like to talk to other listeners of the show and members of the Completionist Club, you can join the Everything Everywhere Daily Facebook group or Discord server. Links to everything are in the show notes. Thank you.

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