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i Missing Chunks of the Earth’s Crust. PHOTO/ SCIENCE ALERT
ALASKA – World te constantly throwing perplexing questions at scientists, with new technologies such as space imaging helping them solve the mysteries.
A mystery that has baffled experts for more than a century refers to a large slab of Earth’s crust that is missing from the geological record.
New evidence has revealed that their disappearance may have been caused by severe glacial erosion that occurred during a time known as “Snowball Earth” when almost the entire planet was covered in ice.
The result is gaps in the sedimentary record that occur when the age of rocks changes drastically due to erosion of previous rocks.
This phenomenon was observed in 1869 at the Grand Canyon in Arizona. Experts noted that the age of the rocks changed drastically and found that this was happening in several places around the world, giving it the name The Great Unconformity.
The authors calculated that on a global average 3-5 kilometers (2-3 miles) of rock was eroded due to glacial erosion so that the rock “disappeared” from the record.
The study’s lead author, Dr Brenhin Keller of the Berkeley Geochronology Center, explains that the scale of rock loss is enormous, and estimates, along with his colleagues, that a billion cubic kilometers (200 million cubic miles) of pre-Cambrian material was lost based on what is thought to exist. .
Their theory suggests that more erosion occurred before the start of the Phanerozoic era than experts previously thought, and they present evidence showing crystals from that era have hafnium and oxygen isotopes.
This isotype is consistent with erosion of older rocks and deposition at low temperatures. Their theory also suggests that this is why there are many asteroid craters that are less than 700 million years old and only two that are older than that.
Regarding the current location of the rock, it is thought that the glaciers that eroded the sedimentary rock also washed it into the sea.
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Where Did All the Rocks Go?
ALASKA – It seems that while scientists are busy piecing together the Earth’s history, our planet is having a bit of a laugh at their expense! I mean, who knew rocks could play hide-and-seek with such enthusiasm? But alas, scientists have found something out of sorts – an actual missing chunk of Earth’s crust. Sounds like a plot twist in a geological thriller, doesn’t it? Spoiler alert: there’s no rock that actually went to the Bahamas!
Picture this: the Earth, back in a time charmingly referred to as “Snowball Earth,” where glaciers were basically the world’s biggest icebergs on a power trip, bulldozing through and erasing chunks of crust like a toddler with a crayon on a fancy wall. Yep, when it comes to geological battles, glaciers take the crown!
The Great Unconformity
So, what’s the deal with this Great Unconformity? In a nutshell, experts have discovered that the history books – or rather, sedimentary records – have some serious gaps. The Grand Canyon first raised the alarm in 1869 (thanks, guys!) when rocks started pulling a disappearing act. And like some kind of geological magician, this phenomenon popped up all over the globe. So many rocks lost, and we didn’t even have a birthday party to celebrate them!
Dr. Brenhin Keller and his team at the Berkeley Geochronology Center calculated that a staggering 3-5 kilometers of rock, or 2-3 miles if you prefer the old school measurement, have been eroded globally. And it gets better; they estimate that a billion cubic kilometers, or if you’re feeling fancy, 200 million cubic miles, of pre-Cambrian material just vanished, leaving geologists scratching their heads.
Glacial Erosion: A Snowy Bandit
The fuzzy, iced-up period of our planet’s history did more than just give us pretty igloos and regretful chills; it acted as nature’s very own shredder, turning solid rocks into little more than geological confetti. Glacial erosion was like the universe saying, “Let it snow! Let it… disappear?” And now, thanks to these icy vandals, we’re left with sediment records filled with more holes than a slice of Swiss cheese.
This massive erosion is likely why scientists have only spotted two asteroid craters that are over 700 million years old. Talk about a long lifespan for a rock, right? Perhaps they need to consider opening a retirement home for aging asteroids—a comfortable place where they can reminisce about their glory days, before those pesky glaciers came along!
Where Are All the Rocks Now?
And where did all that lost rock end up, you might ask? Well, if the erosion didn’t kill them, the glaciers likely sent them packing into the sea. It’s like one big geological game of “Who moved my cheese?” Just imagine the drama beneath the waves as these rocks sit there moaning about their glorious past while being trod upon by fish!
So, as we puzzle over the mysteries of Earth’s crust, let’s raise a glass (preferably of something cold in keeping with our icy theme) to those rocks. They may be missing from the record, but their legacy is far from forgotten. Keep on rocking, Earth! After all, every gap in the sedimentary record tells a tale, even if it’s a tale of an epic geological mishap. Cheers!
What are the implications of the missing chunks of Earth’s crust on our understanding of geological processes?
**Interview with Dr. Brenhin Keller on the Discovery of Missing Chunks of Earth’s Crust**
**Editor:** Welcome, Dr. Keller! Thank you for joining us today to discuss this fascinating discovery regarding the missing chunks of Earth’s crust.
**Dr. Keller:** Thank you for having me! It’s always a pleasure to share insights about our Earth’s geological history.
**Editor:** Let’s dive right in. Your recent study uncovers the mystery of large sections of the Earth’s crust that seem to be missing from the geological record. Can you explain what led to this finding?
**Dr. Keller:** Absolutely. The discovery stems from our analysis of a phenomenon known as the ”Great Unconformity.” This refers to the significant gaps in the sedimentary rock record that have puzzled geologists for over a century. Our research indicates that these gaps can largely be attributed to extensive glacial erosion during a time known as “Snowball Earth,” when glaciers covered much of the planet, erasing vast amounts of rock.
**Editor:** That’s incredible! You mentioned that this erosion was observed as long ago as 1869. Why did it take so long for scientists to connect these dots?
**Dr. Keller:** It’s a complex interplay of factors. For one, the methods and technologies available for studying geological processes have dramatically improved over the years, allowing us deeper insights into Earth’s history. Also, it took time for the scientific community to piece together the evidence from various regions and understand that the changes we see in rock layers aren’t simply local anomalies but rather a global phenomenon.
**Editor:** You spoke about the estimated volume of eroded rock, which is staggering. Can you elaborate on why such a vast amount is significant?
**Dr. Keller:** Of course! We estimate that around a billion cubic kilometers of pre-Cambrian material has been lost due to this glacial erosion. This is significant because it deepens our understanding of Earth’s geological timeline and challenges previous notions about sediment deposition and the timeline of erosion. It also redefines our understanding of Earth’s surface processes and their impact on the fossil record.
**Editor:** Fascinating! Your research also touches on the isotopic evidence found in crystals from that era. What does that tell us about the conditions of the Earth at that time?
**Dr. Keller:** The isotopes we analyzed, particularly hafnium and oxygen, indicate that the rocks were likely eroded and deposited at low temperatures. This tells us that the environmental conditions during this time were quite different from our current understanding of sedimentation processes, and it opens up new paths of inquiry regarding Earth’s climate systems throughout its history.
**Editor:** So, where do you think all the missing rocks have ended up?
**Dr. Keller:** The prevailing theory is that as glaciers flowed over the land, they didn’t just erode the rocks; they transported them to the oceans. This means that while they may be missing from our geological record, they likely exist in the seabeds or within the ocean itself.
**Editor:** Thank you for shedding light on this incredible research, Dr. Keller. It seems like we have a lot more to learn about our planet’s history!
**Dr. Keller:** Absolutely! The Earth continues to reveal its mysteries, and each discovery adds another layer to our understanding. Thank you for having me!
**Editor:** It’s been a pleasure! We look forward to your future findings.
