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The Eye of Africa

3 Apr

The ‘Eye of Africa’ (also known as the Eye of the Sahara) lies within the large east-African country of Mauritania, out in the Sahara Desert. Properly known as the Richat Structure, it is easy to see where its nickname comes from. Looking at it from above, it looks a lot like a big blue eye staring out of the ground. Here’s a picture of the Richat Structure:

Satellite image of the Richat Structure

Satellite image of the Richat Structure

Location of the structure in Mauritania

Location of the structure in Mauritania

Distant satellite image of Mauritania - the structure is still visble

Distant satellite image of Mauritania – the structure is justvisible, even from this far away

It is about 40 kilometers in diameter, and as you can see from the above picture, it is highly visible in satellite pictures.  So, how was this geological wonder formed? Researchers aren’t entirely sure. It was initially thought to have formed as the result of an asteroid impact, but scientists haven’t found any evidence for extraterrestrial involvement, other than its circular appearance.

richat4

Zoomed-in image of the Richat Structure from Google Maps

Geologists now believe that it is most likely to be a very symmetrical ‘geologic dome’. Wikipedia’s summary of a dome is this:

In structural geology, a dome is a deformational feature consisting of symmetrically-dipping anticlines; their general outline on a geologic map is circular or oval. The strata in a dome are upwarped in the center; if the top of a dome is eroded off, the result will be a series of concentric strata that grow progressively older from the outside-in, with the oldest rocks exposed at the center.’

No matter what led to the creation of it, the Richat Structure looks amazing, and I’m hoping that I will get to go and visit it one day.

Doggerland

31 Mar

It’s quite hard to imagine that only a few thousand years ago, there were lands on which people lived that have now completely disappeared into the ocean. But, this is exactly what happened to the area known as ‘Doggerland’.

Up until around 8500-8200 years ago, Doggerland was a large stretch of dry land that linked the European mainland to where the British Isles are today. Here’s a picture to show where it was, compared with what the area looks like today:

This is where Doggerland used to be in Europe. Credit: Max Naylor

This is where Doggerland used to be in Europe. Credit: Max Naylor

The same area today, minus Doggerland

The same area today, minus Doggerland

So, what happened to Doggerland, and how do we know about it?

Archaeologists first started to think that the area may have originally been above sea level in the early 1900’s, when fishing boats in the area would occasionally dredge up the remains of animals that had lived in Europe in prehistoric times, including mammoths and lions (yes, Europe used to have lions!). Plant remains were also brought up and studied by paleobiologists, who found them to be peat from when the land was above sea level and mostly tundra.

To add further interest, prehistoric tools and weapons used by ancient peoples were also found. Archaeologists now believe that Doggerland was occupied by humans during the Mesolithic period (this period started around 10,000 years ago), up until it started to disappear underwater. In fact, some think that it may have been one of the richest hunting and fishing environments available to European humans at the time.

Whilst surveying the area for petroleum, oil-company geologists produced seismic surveys of the land beneath the waves, and in 2012, the Royal Academy of London presented the results of the surveys along with all the artefacts that have been found so far. The seismic surveys allow researchers to see what the land looked like while it was still above sea level, and even Doggerland’s ancient river systems have been mapped in 3D. The largest of these rivers is known as the ‘Shotton River’.

In regards to the disappearance of Doggerland, researchers believe that at the end of the last glacial period, sea levels began to rise dramatically as the climate warmed up. Due to this, Doggerland was eventually submerged under the North Sea, and the British Isles were separated from the European mainland. This probably all happened around 8500 years ago.

Another recent theory claims that after already losing some land to rising sea levels, Doggerland may have become completely submerged as the result of a tsunami that hit the area 8200 years ago. This tsunami was caused by an event known as the ‘Storegga Slide’. It is named this because the event was a massive underwater landslide, occurring off the coast of Norway. The resulting tsunami would have been devastating to Mesolithic people who still lived on Dogger Bank, and after this event, British Mesolithic populations would have been totally separated from the rest.

The yellow numbers represent the height (in meters) of the tsunami waves from the Storegga Slide. Credit: Lamiot

The yellow numbers represent the height (in meters) of the tsunami waves from the Storegga Slide. Credit: Lamiot

One part of Doggerland actually remained for quite a while longer. An island known as ‘Dogger Bank’ emerged when the rest went underwater. Dogger Bank was an upland hill area of the original Doggerland, so the sea levels didn’t rise high enough to cover it. Eventually, however, Dogger Bank also disappeared into the ocean, and this probably happened around 7000 years ago. Here is a map that shows us where Dogger Bank is now:

The red line marks where Dogger Bank used to be. Credit: NASA

The red line marks where Dogger Bank used to be. Credit: NASA

It is fascinating to think that once-populated lands are now totally underwater. Geologists and archaeologists really have the most interesting jobs sometimes!

Derweze – The Door to Hell

31 Mar

In the Karakum (or ‘Black Sand’) Desert, which covers much of the central-Asian country of Turkmenistan, one of the strangest-looking natural gas deposits in the world sits outside of Derweze village. It is a large crater, with a diameter of 230 feet.

Location of Derweze in Turkmenistan

Location of Derweze in Turkmenistan

It is known to the locals as the ‘Door to Hell’, for reasons that become quite obvious when you look at it. The area also smells quite strongly of sulphur, which is quite a ‘hellish’ smell. Here’s some pictures of it:

Distant view of the crater. Credit: P. Lechian

Distant view of the crater. Credit: P. Lechian

Credit: Tormod Sandtorv

Credit: Tormod Sandtorv

If there actually was a doorway to hell, then this place really does resemble how most people would picture it. Why does it look like this, though?

Turkmenistan is known for its natural oil and gas reserves. In fact, it has the fourth-largest natural gas reserves in the world. In 1971, some scientists investigated the field near Derweze to see if they could drill for oil. Upon realising that the field was actually a very large natural gas field, they decided to store the gas, and started drilling operations to get to it. Unfortunately, the ground that they were drilling collapsed and formed a large crater, which released methane gases into the air. Worried that the methane would affect the local population and nearby environment, the scientists decided to burn the gas off. This was considered to be a normal way of getting rid of dangerous gases, and they figured the burning would only last a few days.

It didn’t burn for a few days, though, in fact, it kept burning for 40-odd years. Even today, it is still burning! The hole really does look like some kind of doorway to a fiery underworld, especially at night-time.

The crater as seen at night. Credit: Flydime (http://www.flickr.com/photos/flydime/4671890969/)

The crater as seen at night. Credit: Flydime (http://www.flickr.com/photos/flydime/4671890969/)

So, now you know why it looks like this. I think it would be a great place to visit, but I might never be able to. This is because, as of 2010, Turkmenistan’s government is taking measures to have the hole closed so that it doesn’t influence other natural gas drilling efforts in the region. Either way, the ‘Door to Hell’ is still probably one of the coolest things I’ve ever seen!

What was the Tunguska Event?

28 Mar

Early in the morning of June 17th, 1908, an enormous explosion rocked a remote Siberian area of Russia known as Krasnoyask Krai. The explosion was so massive that it leveled an entire forest of 80 million trees, and it is estimated that it was more than 1000 times more powerful than the atomic bomb that was dropped on Hiroshima during World War II. The epicenter of the explosion was in a swamp near the Podkamennaya Tunguska River, so the event became known as the Tunguska Event.

Location of the explosion's epicenter in Russia

Location of the explosion’s epicenter in Russia

Luckily, despite the size of the event, it is thought that only one person was killed by the blast (although, not so lucky for the poor man who was killed). This was due to the sheer remoteness of the area that was hit. A lot of people did see it happen, though. Witnesses from areas much farther south claimed that they saw something extremely bright and pale blue moving across the sky, and a few minutes later there was a bright flash accompanied by a thunderous sound. A shockwave, which would have registered at 5.0 on the Richter scale, caused people to be knocked off their feet hundreds of kilometers away.

Fallen trees after the explosion, taken in 1927 by Leonid Kulik's expedition to the area

Fallen trees after the explosion, taken in 1927 by Leonid Kulik’s expedition to the area

So, what actually caused this massive explosion? There are several theories. Some have claimed that it may have been caused by the release of natural gases from the Earth’s crust, and others proposed that the explosion may have been a nuclear one; caused by deuterium in a comet undergoing nuclear fusion as it entered the Earth’s atmosphere. Another theory claimed that it was caused by a black hole passing through Earth. And, of course, a lot of people have brought up theories involving UFOs and aliens, especially since as the event is referenced in pop-culture quite a lot.

However, the most widely-accepted explanation is that a large meteoroid or comet caused it, exploding just above the Earth’s surface. This would explain the lack of an impact crater in the area. If this is true, then it was the largest impact event on or near the Earth in modern history. Chemical analysis of soils in the region showed that parts of it contained materials of extraterrestrial origin, further supporting this impact theory.

Meteor. Credit: Navicore

Meteor falling to Earth. Credit: Navicore

Despite the fact that the Tunguska Event is still technically unexplained, I would agree that the impact event theory seems to be the most likely. I think it would be even more interesting if there were a more mysterious explanation, though! It’s also very fortunate that it happened in such a remote area, because if it hit a populated area, then the aftermath would have been far worse.

Bog Bodies

28 Mar

Depending on certain variables, human decomposition is generally a very short process, and a dead body buried underground will normally be completely skeletonized in a maximum period of 50 years. If left out in the open, a body will decompose much faster than this. However, the mummified remains of bodies found in peat bogs, known as ‘bog bodies’, can be up to thousands of years old and almost perfectly preserved.

Tollund Man - Found in Denmark and found to be around 2600 years old. Credit: Sven Rosborn

Tollund Man – Found in Denmark and dated to around 2400 years ago. Credit: Sven Rosborn

Grauballe Man - Found in Denmark and dated to 2300 years ago. Credit: Malene Thyssen

Grauballe Man – Found in Denmark and dated to 2300 years ago. Credit: Malene Thyssen

Rendswühren Man - Found in Germany and dated to around 1900 years old

Rendswühren Man – Found in Germany and dated to around 1900 years old

Brammer Man - Found in Germany and dated to around 500 years ago. Note the still visible beard on his face.

Brammer Man – Found in Germany and dated to around 500 years ago. Note the still-visible beard on his face.

Peat bogs are most prevalent in cold, temperate areas of the Northern Hemisphere (it is possible for them to occur in the Southern Hemisphere, but they are much smaller and less common), and thus, all the bog bodies located so far have been in Northern Europe and North America. Not all are well-preserved, but many still have intact hair, skin and internal organs. So, how is this possible? And, how did the bodies get there in the first place?

Peat bog - Credit to Boréal

Peat bog. Credit: Boréal

The water in peat bogs is cold, acidic, and lacks oxygen, and combined, these factors lead to amazing tissue preservation. Also, tannin (a compound present in tea – this is the stuff that can stain your tea-cups) in the bogs leads to the darker appearance of the skin, and has anti-bacterial properties that aid in the preservation. Unfortunately, the acid in the bog water often destroys the bones, as it dissolves the calcium phosphate in them, leaving only the tissue and hair preserved.

Because of the good soft-tissue preservation, the stomach contents of the bodies can be analysed in some cases, which tells us something about the diets of people during whichever period they lived in. In cases where bones have been preserved, archaeologists can tell what kinds of activities the person engaged in, and even if they were right-handed or left-handed! Also, forensic techniques have been applied to some of the bodies in order to reconstruct their appearances. Here’s some examples:

Reconstruction of Lindow Man's face - Credit: www.culture24.org.uk

Reconstruction of Lindow Man’s face. Credit: http://www.culture24.org.uk

Reconstructed face of the Girl from Uchter Moor - Credit to AxelHH

Reconstructed face of the Girl from Uchter Moor. Credit: AxelHH

The bodies that have been recovered from peat bogs cover a very wide time span, with some dated from 10,000 years ago and others all the way up to World War II. It seems that some of the bodies belonged to unlucky individuals who simply fell in, but many others appear to have died violently, after which they were thrown into the bogs. This may have been as punishment for a crime, or, perhaps it was human sacrifice. The majority of the violently-killed bodies have been dated to the Iron Age (this began around 3000 years ago, and lasted about 500 years), so some archaeologists believe that Iron Age groups may have had this means of execution or ritual sacrifice as a cultural tradition.

Overall, the bog bodies are not only interesting, but very useful to historians, archaeologists, and anthropologists, as they yield so much useful information in regards to past peoples who lived around the bogs. For more reading on the topic, check out

http://archive.archaeology.org/online/features/bog/

http://ngm.nationalgeographic.com/2007/09/bog-bodies/bog-bodies-text

The Devil’s Triangle

27 Mar

Almost everyone knows stories about the Bermuda Triangle; the sea between the three points of Bermuda, Florida, and Puerto Rico which is apparently responsible for the demise of many ships and planes due to ‘mysterious circumstances’. However, hardly anyone has heard of the allegedly equally-dangerous Devil’s Triangle (otherwise known as the Devil’s Sea or the Dragon’s Triangle).

This particular ‘triangle’ has apparently claimed the lives of many people over the years, and stories hold that some supernatural force causes ships to disappear. There have been claims that other paranormal events occur in this region too, like time lapses and electronic malfunction. Some people also believe they have seen UFOs in the area. Also, the ‘Dragon’s Triangle’ name apparently originates from ancient tales of fire-breathing dragons being in the area.

Japanese dragon painting by Ogato Gekko. Credit: Adam Cuerden

Japanese dragon painting by Ogato Gekko. Credit: Adam Cuerden

So, where exactly is the Devil’s Triangle? The location differs depending on who you ask, but it is thought to be somewhere in the Pacific Ocean, anywhere between 100 – 1300 km from Japan. That’s not exactly specific… however, most believe that the Devil’s Triangle is close to the Izu Islands, a chain of islands not too far south of Tokyo.

Map of the Izu Islands

Map of the Izu Islands

I wasn’t able to find any sources as to where the legend first definitively arose, aside from the ancient dragon legends, but a lot of it had to do with a book written by Charles Berlitz, called ‘The Dragon’s Triangle’. In this book, Berlitz claimed that Japan had officially declared the area a danger zone after they lost 700 people from military ships during 1952-1954. The ships apparently vanished into thin air, at which point Berlitz claims the Japanese government sent a research ship with 100 people to investigate. This research vessel promptly vanished too.

Now, this legend would be very spooky… if there were actually any truth to it. The oceans around Japan are known for their seismic and volcanic activity, so disappearances of ships/boats isn’t exactly an abnormal occurrence. The ‘fire-breathing dragons’ of the ancient legends could have just been volcanoes.

Credit: Oliver Spalt

Credit: Oliver Spalt

Also, it seems that Berlitz sensationalized the whole issue, along with simply making stuff up. The research ship, the Kaiyo Maru No. 5, actually only had 31 people aboard, and was found to have been destroyed by a volcanic eruption while it was investigating an underwater volcano. The military vessels that Berlitz referred to were actually just fishing vessels, and he conveniently ignored the fact that hundreds of fishing vessels are lost over the years in all different regions of the Pacific, not just the Izu Islands region.

I love reading about weird and creepy things, so it would be great if the stories surrounding the Devil’s Triangle were true. But, unfortunately, it seems like it is just another story that was made up to entertain people, or perhaps warn them about the real (seismic/volcanic) dangers of the area.

Wave Rock

26 Mar

There are many well-known natural formations all over the world; The Grand Canyon, Niagara Falls and Mt Everest, to name a few. In Australia, there is a particularly spectacular formation that many of our readers may not be aware of, due to its fairly remote location. I am referring to what is known as ‘Wave Rock’; an enormous rock formation in south-eastern Western Australia, which is the largest state in Australia.

Located 3km (or about 2 miles) from the small town of Hyden, this natural geological formation attracts approximately 140,000 tourists a year. The rock itself is a large granite formation that has been dated to 2.63 billion years old, and was created through complex geological processes. As you can see from the picture below, it closely resembles an ocean wave, hence the name, and is nearly 50 feet (14m) high and 350 feet (110m)  across.

Wave Rock. It stands 14m high and close to 110m long.

Wave Rock. It stands 14m high and close to 110m long.

While there are no creepy mysteries relating to Wave Rock itself, the local indigenous people stayed clear of the area for fear of the spirit ‘Mulka’.

Here is the story of Mulka sourced from the Wave Rock website

Legend of Mulka’s Cave

“The name Mulka comes from an Aboriginal legend associated with the cave. Mulka was the illegal son of a woman who fell in love with a man with whom marriage was forbidden according to their law.

It was believed that as a result of breaking these rules she bore a son with crossed eyes. Even though he grew to be an outstandingly strong man of colossal height, his crossed eyes prevented him from aiming a spear accurately and becoming a successful hunter.

Out of frustration it is said Mulka turned to catching and eating human children, and he became the terror of the district. He lived in Mulka’s cave, where the imprints of his hands can still be seen, much larger and higher than that of an ordinary man.

Apparently, his mother became increasingly concerned about him. When she scolded him for his anti-social behaviour he turned on his own mother and killed her. This disgraced him even further and he fled his cave, heading south.

The Aboriginal people of the area, outraged by Mulka’s behaviour, then tracked down this man who had flouted all the rules. They caught him near Dumbleyung, 156km south west of Hyden, where they speared him to death. Because he did not deserve a proper ritual burial, they left his body to the ants: a grim warning to those who break the law.”

So, how did this formation come to be? As previously stated, the geological processes that led to the formation of Wave Rock are quite complex, but I will attempt to break it down to a simple, easier to understand explanation for our readers. Basically, Wave Rock is a part of a much larger rock known as Hyden Rock, and the shape was created by continuous erosion of the softer rock beneath the upper edge, in the process of weathering. This occurred over many millions of years. Eventually, this resulted in an ‘undercut’ base with a rounded overhanging shape, and ended up in the wave shape that we see today.

Having lived in Western Australia most of my life, I have visited wave rock numerous times. If you ever decide to visit Western Australia, I highly suggest making the effort to go and see the rock and some of the Australian countryside whilst you are there.

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