Category: geology

Readers’ wildlife photos

December 19, 2024 • 8:15 am

Today is the third and last part of Athayde Tonhasca Júnior’s travelogue, including ancient paintings, from Brazil (part I is here and part II is here).  Athayde’s captions are indented, and you can enlarge his photos by clicking on them. Without further ado:

Back in the day. Way, way back, Part III

JAC: the introduction to part I:

The Brazilian north-eastern hinterland is not a hospitable place for an outsider. Except for a short and intense rainy season, this is a dry, dusty and sizzling territory: a land of the cactus, thorny scrub and stunted trees. The native Tupi speakers called this semiarid region caa (forest, vegetation) tinga (white), and the term was adopted by the Portuguese settlers as caatinga. But the apparent harshness of the landscape misrepresents its ecological importance. The caatinga is a biota found nowhere else in the world, harbouring more than 2,000 species of vascular plants and vertebrates, with endemism in these groups ranging from 7 to 60%. And like every other Brazilian ecoregion, the caatinga has been severely degraded and fragmented. But its plants and animals have one place of refuge: the Serra da Capivara National Park in the state of Piauí. The park is a haven to numerous birds and endangered mammals such as the giant anteater (Myrmecophaga tridactyla), three-banded armadillo (Tolypeutes tricinctus), jaguar (Panthera onca) and other cats, and the maned wolf (Chrysocyon brachyurus).

The 129,140-ha park contains a massif of sandstone sediments formed some 430 million years ago when the whole area was submerged under a sea. The massif, smoothed by water and wind, was once the seabed, and pebble conglomerates on top indicate an overlying beach.

New:

In 1963, Niède Guidon organized an exhibition of prehistoric paintings in São Paulo. She was approached by one of the visitors with some pictures of ‘Indian paintings’ from places near his property in Piauí, a remote and forgotten region in the 60s. Guidon saw right away that those pictures were something completely different. She only managed to visit the area about 10 years later, and thanks to her, Serra da Capivara was discovered by the outside world – including Brazilians.

Pedra Furada (pierced rock), near the place where Guidon’s excavations provided evidence for a much earlier human presence in South America than previously thought:

Zuzu, one of the oldest human specimens found in South America. Assigned as female at discovery, later transitioned to male by researchers. Zuzu died approximately 9,600 years ago (Museu do Homem Americano).

How Zuzu may have looked (Santos & Moraes, 2023):

Superstition helped preserve Serra da Capivara. Tales of eerie voices and floating apparitions meandering through the canyons kept people away (can you see the face profile on the left wall?). Local elders warned youngsters about bad things happening to those who disturbed the ‘Indian paintings’:

Many of Serra da Capivara‘s pre-historic paintings suggest that life among the cliffs and canyons was not peaceful and idyllic. Here we witness a possible murder or execution:

A shagging scene, but not of a vanilla variety. The supporting character on the right hints of a threesome or, ominously, a non-consensual act:

Leaping deer:

Despite having survived for thousands of years, the wall paintings suffer the ravages of weather. The most vulnerable ones have been shielded from running water:

Some of the park’s residents like the ubiquitous coroa-de-frade (friar’s crown, Melocactus zehntneri) are on standby to inflict pain on the absent minded:

A slice of the bottom of the sea. Our minds need training to see things in geological time frames:

A parting view of Serra da Capivara. If you sit here for a while, you’d be taken by the silence. Nothing seems to move, and you only hear your own breathing:

Going home: 300 km to the airport on a mostly empty road, although you need to watch for goats grazing by the roadside. All that changes when you pass the towns along the way: mountains of plastic bags, rubbish and rubble everywhere. Places that don’t do justice to a small paradise hidden in the caatinga heartland:

A visit to Bryce Canyon

October 30, 2024 • 9:00 am

Yesterday we took a drive to Utah’s Bryce Canyon National Park, a 2.5-hour trip from where I’m staying in Ivins, Utah.  Bryce is located where the red pin is in this Wikipedia map:

SANtosito, CC BY-SA 4.0, via Wikimedia Commons

It turns out that Bryce is one of the most beautiful places I’ve seen in America—indeed, anywhere on Earth. To me, its splendor, exemplified by the “amphitheaters” that contain the red geological spires known as hoodos, is unparalleled. I’ll show some photos below. First, a few words from Wikipedia:

The major feature of the park is Bryce Canyon, which despite its name, is not a canyon, but a collection of giant natural amphitheaters along the eastern side of the Paunsaugunt Plateau. Bryce is distinctive due to geological structures called hoodoos, formed by frost weathering and stream erosion of the river and lake bed sedimentary rock. The red, orange, and white colors of the rocks provide spectacular views for park visitors. Bryce Canyon National Park is much smaller and sits at a much higher elevation than nearby Zion National Park. The rim at Bryce varies from 8,000 to 9,000 feet (2,400 to 2,700 m).

And the geology, which explains these bizarre formations:

The Bryce Canyon area experienced soil deposition that spans from the last part of the Cretaceous period and the first half of the Cenozoic era. The ancient depositional environment varied. Dakota Sandstone and Tropic Shale were deposited in the warm, shallow waters of the advancing and retreating Cretaceous Seaway (outcrops of these rocks are found just outside park borders).

The Laramide orogeny affected the entire western part of what would become North America starting about 70 million to 50 MYA. This event helped to build the Rocky Mountains and in the process closed the Cretaceous Seaway. The Straight Cliffs, Wahweap, and Kaiparowits formations were victims of this uplift. The Colorado Plateaus rose 16 MYA and were segmented into plateaus, separated by faults and each having its own uplift rate.

This uplift created vertical joints, which over time preferentially eroded. The soft Pink Cliffs of the Claron Formation eroded to form freestanding hoodoo pinnacles in badlands, while the more resistant White Cliffs formed monoliths The brown, pink, and red colors are from hematite (iron oxide; Fe2O3); the yellows from limonite (FeO(OH)·nH2O); and the purples are from pyrolusite (MnO2).

So we have a sedimentary sandstone formation that of course formed the seabed, and, under the pressure of colliding tectonic plates (I’m dong the best I can here), produced a huge uplift of the seabed, with Bryce being part of a huge sandstone cliff.  Thrust above the ground, the cliff was subject to erosion as well as weathering as frost and ice invaded the cracks in the soil. That erosion of softer bits, as well as the cracking, created structures like these. These are “mini-hoodoos” that you see before you enter the Park itself:

The area is called “Dixie” because there was a period during which settlers tried to grow cotton in the area. This endeavor ultimately failed, probably because of extreme dryness and lack of water. They haven’t yet purged the name “Dixie” from many institutions and parks, but that will happen. There is even a “Dixie Technical College.”

These are just small previews of the Big Show that is Bryce Canyon:

Entering the park, you’re warned to stay away from prairie dogs (cute rodents in the genus Cynomys) who build extensive underground tunnel systems. Their fleas carry the bacterium the causes bubonic plague, which persists at a low level in the U.S (about nine cases a year in the past couple decades). Now that we have antibiotics, getting plague is no longer the death sentence it was in the Middle Ages.

The glories of the park are the series of hoodoo-containing ampitheaters, which you can see from above by climbing up a short path. They are breathtaking:

These spires are huge, not just small excrescences:

A panorama: be sure to click to enlarge the photo:

The day was bloody cold, with snow on the ground during much of the two-hour drive and some near white-outs. But the weather cleared sufficiently when we got to the Park so that photography was good, in muted light. Here’s my friend Phil Ward standing on the edge of the cliff, trying not to slip and fall into the canyon.

. . . and Professor Ceiling Cat in the same place: a vanity photo

More of the Canyon. It is much smaller than Zion but more breathtaking. You can pretty much take in the whole thing by climbing to one of the lookout points (this one was about 8,000 feet high, so you get out of breath hiking up):

Another panorama: click to enlarge:

After we froze our ears, hands, and noses (there was a stiff wind up there, and the temperature was below freezing), we parked the car overlooking some scenery and had a healthy Phil Ward-ian lunch (turkey breast and cream cheese on walnut bread, along with a ginger drink, a banana, and an apple). Then we repaired to the visitor center, which had good explanations and diagrams of how the park was formed. There were also relics from the Native Americans who lived in this area as well as the Mormon settlers. Here is a water jug from the late 1800s made of resin-coated wood:

There were lots of Bryce-related geegaws for sale in the gift ship, and I had a bit of fun with two pack rat puppets (rodents of the genus Neotoma).

Then it was time for the long drive home, and once again we had to go through snow and rain. But we were fortunate that the weather in the Park was good when we were there, and we could truly say this:

And when we got home, one of the people who co-owns the beautiful house where I’m staying served us raw oysters, grilled oysters, grilled burgers, and then two beautiful grilled ribeye steaks:

And the sun will come out tomorrow (in fact, today). The view from the house where I’m staying:

If you’re in southern Utah, you must visit both Bryce Canyon and Zion National Parks. But if you can visit only one, it must be Bryce. Truly, I’ve traveled a lot of this planet, and seen some beautiful places, but Bryce is surely among the top ten. (Others include Mt. Everest from Kala Pattar, Machu Picchu, the Taj Mahal under a full moon, and almost any part of Antarctica, as well as the giant sequoias of California.)

Feel free to list below the most beautiful places you’ve seen! This might help me amend my bucket list.

Living bacteria found in 2-billion-year-old rocks

October 20, 2024 • 9:30 am

Up to now, the oldest rocks known to contain living bacteria—microorganisms that were alive since the rock were formed—were sediments from about 100 million years ago.  Now, a group of researchers from South Africa, Japan, and Germany report finding living bacteria in rocks 20 times older than that: over two billion years ago.  And those bacteria were alive, and presumably dividing.

This finding, published in Microbial Ecology, suggests that if there was once life on Mars, one might be able to find its remnants by examining rock samples the way these researchers did.

The paper can be accessed by clicking on the screenshot below. You can also find a pdf here and a short New Scientist article about the discovery here.

The details: the researchers drilled into 2-billion-year old igneous “mafic rocks” in the Bushveld Igneous Complex of South Africa, described by Wikipedia as “the largest layered igneous intrusion within the Earth’s crust“.  Drilling down 15 meters using a special drilling fluid to lubricate and cool the drill bit, they extracted a 30-cm (about 12-inch) core of rock with a diameter of 8.5 cm (3.3 inches). They then carefully cut into this core, making sure not to contaminate it with modern bacteria.

Here’s a photo of part of the Bushveld intrusion showing the igneous rock (see caption for details:

(From Wikipedia): Chromitite (black) and anorthosite (light grey) layered igneous rocks in Critical Zone UG1 of the Bushveld Igneous Complex at the Mononono River outcrop, near Steelpoort Photo: kevinzim / Kevin Walsh, CC BY 2.0, via Wikimedia Commons

Remember that igneous rock is formed when other rock is melted by extreme heat and then cooled.  As this rock cooled, there were cracks in it that were filled with clay during the process, and, when the rock was solid, the clay was impervious to further intrusions. In other words, the clay in the rock cracks were 2 billion years old. But was the clay and its inhabitant bacteria that old? (See below.)

What they found.  To test whether what they saw in the cracks (bacteria!) were really original, 2-billion-year-old bacteria rather than organisms that had entered the rock after formation or were contaminants during the drilling or handling, the authors dissolved tiny fluorescent microspheres in the drilling fluid, spheres smaller than bacteria. Tests showed that although the microspheres were visible in the fluid sample, they were not seen within the rock (of course the researchers took great care to not contaminate the rock either during extraction or when it was cut and examined).  Here is their schematic of how the cores were extracted and handled (figure from the paper). Note the flaming to kill anything living on the outside of the core (click all figures and photos to enlarge them):

Here is a fluorescent sample of drilling fluid (on the left), showing many microspheres, and a sample of the rock showing DNA-stained bacteria on the right, which appear as green rods. The scale is the same, so you can see that the microspheres are smaller than the bacteria:

(from paper): Microscopic inspection of the drill fluid sample. A 1000-fold magnification images of fluorescent microspheres and (B) microbial cells stained by SYBR Green I

The presence of living organisms (at one time) in the cracks was also confirmed by finding “amides I and II,” which, say the authors “are diagnostic for proteins in microbial cells.”  The New Scientist paper adds that the cell walls of the bacteria (if they are indeed “bacteria”!) were intact, which, says author Chen Ly, is “a sign that the cells were alive and active”.

What did the bacteria eat? The paper’s authors say that “indigenous microbes are immobile and survive in the veins by metabolizing inorganic and/or organic energy available around clay minerals.” They do add that there is doubt about the ages of the clay cracks, as they might actually have been formed much more recently than two billion years. Both the paper and the NS blurb are careful not to say that the bacteria have actually been in the rocks for two billion years, but that seems to be the tacit assumption.

Here are two photos from the paper of one of the bacteria-containing cracks. The color indicates, say the authors, spectra from silicate minerals and microbial cells

The upshot and implications: These are by far the oldest rocks even seen to contain indigenous (rather than externally-derived) living organisms, presumably bacteria. It’s not 100% clear that the organisms are themselves 2 billion years old, but the assumption here is that they are. New Scientist floats the idea that we should do this kind of analysis to look for life on other planets, most notably Mars:

This discovery may also have important implications for the search for life on other planets. “The rocks in the Bushveld Igneous Complex are very similar to Martian rocks, especially in terms of age,” says Suzuki, so it is possible that microorganisms could be persisting beneath the surface of Mars. He believes that applying the same technique to differentiate between contaminant and indigenous microbes in Martian rock samples could help detect life on the Red Planet.

But they quote one critic who asks the same questions I do above, and insists that the bacteria aren’t as old as the rocks. (For one thing, bacteria couldn’t survive in an igneous rock when it was very hot during formation.)

“This study adds to the view that the deep subsurface is an important environment for microbial life,” says Manuel Reinhardt at the University of Göttingen, Germany. “But the microorganisms themselves are not 2 billion years old. They colonised the rocks after formation of cracks; the timing still needs to be investigated.”

Questions that remain:

1.) Are the bacteria themselves two billion years old? I’m not sure how they would investigate this if the clay could have entered the rock and then been sealed into the cracks a long time after the igneous rock was formed.

2.) If the bacteria that old, were they dividing during that period? I don’t see any mention of seeing dividing cells, and the authors say that the cells were effectively trapped in the clay. If so, could they still divide, or are we seeing the original bacteria, perhaps two billion years old and still kicking? This raises another question:

3.) Were the bacteria “alive” during this period? If they were really metabolizing over this period, then yes, they were alive. But if their metabolism was completely shut down, what do we mean by saying they were alive? The NS piece says that the presence of cell walls means that the bacteria were “alive and active”, but is that really true?

4.) Finally, if these things had stainable DNA, can it be sequenced? It would be interesting to get the DNA sequences of these bacteria, which they’d presumably have to do by culturing them. Although we now have methods to get the DNA sequence of a single bacterium by sequencing its RNA transcripts (see this report), you’d have to pry the bacteria out of the clay to do that. And if you can get the sequence, does it resemble that of any living bacteria, or are these ancient forms very different from today’s microbes?  (If they do resemble modern bacteria—for evolution would be very slow when cell division takes millions of years—then perhaps we could culture them.)

The biggest question, of course, is #1 above. I’m hoping that these things really are two billion years old, for what we’d then have is a very, very ancient bacterial culture. But I’m very dubious that we’ll find bacteria in Martian rocks.

 

h/t: Matthew Cobb, for alerting me to the relevant. tweet

 

Science or not science? Geology in New Zealand

August 1, 2024 • 9:30 am

Let others bang on about Trump; I’ve passed my judgment and have nothing to say about the loon. My brief this morning, as it is so often (sorry!) is New Zealand, which I see as the country of the world most captured by woke ideology (in this case, what we call DEI). In NZ, this takes the form of holding everything indigenous as sacred, and any criticism of such things cannot and will not be tolerated within the country. (I am safe in America.)  New Zealand may be a model of what will happen in countries like the US and UK, so we should pay attention.

What really burns my onions in when this kind of capture affects science, so that schoolkids—all the way up to college—are taught that science is not only compatible with the local “way of knowing” (Mātauranga Māori, or MM), but almost coequal, despite the fact that MM is a composite of empirical trial-and-error knowledge, spirituality, religion, myth and legend, and morality.

Today’s example, sent to me by yet another anonymous Kiwi (not the same one as yesterday!) puts the lie to the fact that this kind of capture is trivial and should be ignored. There are actually two articles, both from a government geological agency, GNS Science.

GNS Science is, according to Wikipedia,

. . . .a New Zealand Crown Research Institute. It focuses on geology, geophysics (including seismology and volcanology), and nuclear science (particularly ion-beam technologies, isotope science and carbon dating).

GNS Science was known as the Institute of Geological and Nuclear Sciences (IGNS) from 1992 to 2005. Originally part of the New Zealand Government’s Department of Scientific and Industrial Research (DSIR), it was established as an independent organisation when the Crown Research Institutes were set up in 1992.

As well as undertaking basic research, and operating the national geological hazards monitoring network (GeoNet) and the National Isotope Centre (NIC), GNS Science contracts its services to various private groups (notably energy companies) both in New Zealand and overseas, as well as to central and local government agencies, to provide scientific advice and information.

It’s analogous to the U.S. Geological Survey.

Click to read the summary page on “Minerals and Metals in New Zealand”:

After informing us that New Zealand is home to many minerals and metals (which are “not rocks”), and that these minerals and metals have many different uses, the page segues into spirituality and religion, which occupies fully half the page. Here you go:

Mātauranga Māori and minerals

Over hundreds of years, through interaction with and adaptation to the environment, Māori have developed a deep understanding and knowledge of minerals.

Māori believe that each rock and mineral type emerges from the Earth with its own story, its own whakapapa (genealogy) relating to its origin – hei koha tū, hei kura huna a Papa.

According to Māori tradition (pūrākau), Pūtoto, the god of magma, constantly seeks outward paths towards the Earth’s surface. On his upward journey, Pūtoto leaves many deposits — koha (gifts) for the guardians of the Earth’s bedrock and crust. Through the natural processes of heating, compression, solidification, weathering and erosion, Pūtoto’s deposits generate new varieties of stones, rocks, sand and minerals.

Pounamu (also known as jade or greenstone) is one of New Zealand’s most iconic mineral material. Pounamu is the Māori collective term for the semi-precious stone scientifically referred to as nephrite (kawakawa, kahurangi, inanga) or semi-nephrite. Ngāi Tahu are the kaitiaki (guardians) of pounamu and have a desire for it to be managed under the principle of ‘Tiakina he tino taonga Pounamu mō tātou, ā, mo kā uri ā muri ake nei’ (Care for the precious treasure Pounamu for all of us and our children who follow us). GNS Science provides scientific research and information to assist Ngāi Tahu with achieving these aspirations for now and for the benefit of future generations.

Well, I’m prepared to believe that the Māori know what uses metals and minerals have, but of course without modern science they don’t know how to make them into compounds or even the chemical composition of these substances. The geological origin of minerals, as recounted above, comes not from indigenous “ways of knowing” but also from modern science.  What distresses me is that the bit above mixes geology with legend. That isn’t science but anthropology—or even religion.  Seriously, are the things that traditional knowledge tells us of any use in a geology institute, or is it simply a form of virtue signaling? (They are, of course, of some use in anthropology or sociology.)

As the reader who sent this to me remarked,  “They’re trying to be both scientists and not at the same time!”

I have no idea whether the next article has anything to do with diluting geology with religion, but it’s an indication of what’s happening to science in New Zealand. Click to read:

The bad news:

GNS Science is proposing to axe dozens of jobs – the latest in a rolling series of shake-ups that have rocked the public and science sectors.

The Crown Research Institute has begun consulting staff on its cost-cutting proposals, which would disestablish 103 positions, of which one-quarter were vacant.

While 77 staff were affected by the plans, GNS was also proposing to establish 37 new roles, which it said would help the institute to “address its challenges and rise to its opportunities”.

“The change process anticipates these new positions will offer redeployment opportunities for some of our impacted staff,” GNS said in a statement.

The agency said it’d been focused on operating with fiscal prudence, seeking cost savings where possible and looking hard at any discretionary spending.

“Now, considering the size of our workforce alongside other cost-saving measures is a difficult but necessary step on a longer journey to financial sustainability,” it said.

“We are now encouraging staff to engage and provide feedback on the issues we face and our change proposals.”

It wasn’t yet clear how some of the agency’s vital functions – such as monitoring natural hazards or climate change research – might be affected.

Now I’m sure that New Zealand, a country of immense geological interest (it sits atop two tectonic plates) is full of excellent science-oriented geologists. I wonder what they think when their own governmental organization says stuff like this:

Ngāi Tahu are the kaitiaki (guardians) of pounamu and have a desire for it to be managed under the principle of ‘Tiakina he tino taonga Pounamu mō tātou, ā, mo kā uri ā muri ake nei’ (Care for the precious treasure Pounamu for all of us and our children who follow us). GNS Science provides scientific research and information to assist Ngāi Tahu with achieving these aspirations for now and for the benefit of future generations.

Is that the job of geologists?

On another page, you can see the “Framework of GNS”, described as “MAHIA Framework – the values that guide our work at GNS Science”.  These articles always have colorful diagrams for those who need pictures.

The New Zealand government unites indigenous knowledge with “western science” by claiming that gods cause earthquakes

July 24, 2024 • 11:45 am

A comment by reader Chris Slater called my attention to this article from GeoNet, an organization described as providing “geological hazard information for Aotearoa New Zealand.”  It’s also

. . . . sponsored by the New Zealand Government through its agencies: Natural Hazards Commission Toka Tū Ake, GNS Science, Toitū Te Whenua Land Information New Zealand (LINZ), the National Emergency Management Agency (NEMA) and the Ministry of Business, Innovation and Employment (MBIE).

The hazards include volcanoes, earthquakes, landslides, and tsunamis.  Useful, right? And of course the monitoring is done using scientific methods (see here for earthquakes, for instance), because you must use modern science to make the best predictions.

But this is New Zealand, and so GeoNet had to drag in some indigenous knowledge to satisfy the Zeitgeist; in this case, the addition was arrant superstition. This article, which you can read by clicking on the headline, invokes gods as a cause of earthquakes.  It’s all metaphor, of course, but it’s done to satisfy the claim that both kinds of “knowledge” is the optimal mixture for understanding the world.

The subheadline echoes the headline:

The weaving together of different knowledge strands, Mātauranga Māori and western science, strengthens our understanding of our whenua (land) and supports conversations on how we can be better prepared for natural hazard events, such as an Alpine Fault earthquake, together.

Note the assertion that combining indigenous “ways of knowing” with what they persist in calling “western science” (which is no longer western) will make for a better understanding of nature.  But Mātauranga Māori doesn’t just include practical knowledge gleaned from trial and error: it also includes superstition, ethics, morality, legend, and religion.  And here they bring in the religion. 

An excerpt (my bolding)

The Alpine Fault is the longest naturally forming straight line on earth. It marks the meeting of two large tectonic plates and has formed over millions of years, stretching longer, lifting our landscape up out of the ocean, and creating the peaks of Kā Tiritiri o te Moana (Southern Alps) with every large earthquake it generates.

According to Ngāi Tahu creation stories, earthquakes are caused by Rūaumoko, the son of Ranginui (the Sky Father) and his wife Papatūanuku (the Earth Mother). Māori have experienced rū whenua, which means ‘the shaking of the land’ for centuries.

Science tells us that Rūaumoko rumbles the Alpine Fault about every 300 years, and the last time was in 1717. These big earthquakes have been happening for millions of years and the next one is not a case of if, but when. The next large Alpine Fault earthquake will be long and strong and significantly alter the landscape of Te Waipounamu as we know it. Landslides, liquefaction, river changes, flooding, tsunami, and aftershocks are all likely.

A large Alpine Fault earthquake happening in our lifetimes is no doubt a scary thought! However, understanding how our whenua has moved in the past helps us prepare to move with it in the future. While we can’t predict when it will happen, we can work together to be better prepared for it by sharing our mātauranga (knowledge), science, and experiences of past earthquakes and emergencies to raise awareness, build understanding, and strengthen our relationships. The better connected we are beforehand, the easier it will be to support each other during and after a catastrophic event.

This is a hot mess.  Dragging in Māori religion not only doesn’t add anything to the prediction of earthquakes, but is likely to confuse students who think that religious mythology is inherent in this prediction. What on earth can it mean to say that “Science tells us that Rūaumoko rumbles the Alpine Fault about every 300 years. . “?  That is simply a flat-out lie.  The pressures on the tectonic plates makes them slip roughly once every 300 years. It’s not due to the actions of a god who decides to rumble the earth about every 300 years (does he get bored?).

It is a disservice—in fact, an insult—to geologists to add to their science the idea that gods are shaking the earth. It is an embarrassment to New Zealand’s government that they are more or less forced to mix indigenous myths with science to pretend that they can reinforce each other. And that pressure comes from trying to sacralize the indigenous people and satisfy, so they think, are the demands of the 1840 Treaty of Waitangi. But that treaty says nothing about indigenous ways of knowing being made coequal to modern science.

Yes, indigenous knowledge may be a useful addition to some limited scientific endeavors, but this is not one of them. Get the gods out of geology!

Readers’ wildlife photos

June 22, 2024 • 8:15 am

Today, wildlife is construed as including geology, in particular, photos from reader Kevin Elskin of a cave formation in Arkansas. Kevin’s notes are indented, and you can enlarge the photos by clicking on them.

I was born and raised in Arkansas, and happily so. The Ozark Mountains are a fascinating place. Historically, Osage tribes hunted the area, but they never really settled it. The mountains are hundreds of millions of years old, slowly weathering into oblivion. Maybe their most majestic days are behind them, but they still have secrets to share if you care to go looking.

Today I would like to share some photos of Blanchard Springs Caverns, owned and operated by the United Stated Forest Service. It is located in north central Arkansas, due north of Little Rock and maybe forty miles from Missouri as the crow flies. Basically, the middle of nowhere. It is near Mountain Home, Arkansas, a small town noted for its folk music.

The main tour of Blanchard Springs is the Dripstone Trail. Elevators take you just over 200 feet underground, where you enter a cavern up to six stories tall. It is a live cave, still in the process of creating formations.

The first photo I took tries to capture the enormousness of the cavern. If you look carefully you can see the trails and walking paths through the cavern.

The following photos are of various formations; as much as possible I tried to include walkways to give some evidence of perspective.

Here is the cleverly named ‘Battleship’ formation:

As you reach the end of the tour you come to the soda straw room. I did a poor job of capturing it, but essentially there are tubular stalactites, each hollow with a bit of water clinging to the end.

Lastly, you can take a short drive and see where Blanchard Spring Creek empties from the caves:

So come visit Arkansas. Yeah, you are going to see Confederate license plates and plenty of Trump 2024 signs. But you will also meet some nice, friendly people and see some charming and beautiful sights. And there is nothing wrong with that.

Readers’ wildlife photos

February 22, 2023 • 8:15 am

Today we have some lovely geology photos, relating to the early Earth, from reader Rodney Graetz. Rodney’s narration is indented, and you can enlarge his photos by clicking on them:

Pages from the history of planet Earth

The history of planet Earth is recorded by its rocks in the language of their composition and age, and we have only recently been able to read it.  The history is a significant component of human understanding.  It informs us about Early Earth events, such as the origin of Life, and exposes the absurdity of our creation myths.

Here are eleven Australian pages from Earth’s History.

The most interesting pages in Earth’s history are the oldest, for Deep Time is a synonym for Early Earth.  Some Australian landscapes contain old rocks, and one area, The Pilbara, has become an international focus for Early Earth research.

This is a typical Pilbara landscape looking hot and subdued by age.

At my feet was this layer-patterned rock, a fossilised stromatolite – a structure that is recognisable because living stromatolites still exist.  They are the result of a repeated sequence of sticky film-living, bacteria-like life forms being covered by fine sediment, then a new living film is generated and covered, and so on.  The age of this fossilised life is 3400 million years (My),one of the oldest, globally.  The Earth formed at 4543 (My) ago so, the Earth’s age when this stromatolite formed was (4543-3400), or1143 (My).  It took more than a billion years for Life to appear in Earth’s history.

A low conical hill at dawn, topped with an incongruous cap.  It also has that old, subdued look, and rightly so for measurements revealed the cone to be deeply weathered granite aged at 2950 (My), or Earth Age 1600 (My).  The cap rock is of a ‘young’ sandstone of ‘dinosaur’ time, 146-66 (My).

A broken block from a layer of fossilised stromatolites strikingly illustrates its structure, the repetitive layering of life activity and its burial.  Aged as 2740 (My).  Earth Age 1803 (My).

During the period 2470 – 2450 (My), the oceans ‘rusted’.  The soluble (Ferrous, green) Iron compounds were oxidized to insoluble (Ferric, red) form and precipitated out.  The proposed cause was increasing and fluctuating atmospheric oxygen known as The Great Oxidation Event.  The result was this example of Banded Iron Formation (BIF), known globally from many areas of ancient rocks, and the primary source for contemporary iron mining.  Earth’s landscapes, rocks, and soils have been ferric red ever since.  Earth Age 2073 (My).

Leaving the Pilbara, and moving to Northern Australia, this rock is uninteresting in appearance but puzzlingly isolated on a floodplain.  Its measured age is 1800 (My), Earth Age 2743 (My).  Much more interesting is that this outcrop, and the crust it is part of, was once a component of a now-dispersed supercontinent, Nuna/Columbia, located at 30° N, or approximately 5000 km (3000 mi) from where it is today.  The Earth’s crust, in action.

Now to Southern Australia, the Flinders Ranges.  A vertical-up photograph of a rubble-like rock layer overlying a totally different rock type.  The top layer of various sized boulders, gravel and sand is the unmistakable signature of glacial action, that was progressively discovered to be both massive and extensive.  Mapped globally, it was named the Cryogenian Period, 720 – 660 (My), but because it was found to be so widespread over 60 (My), it is thought the entire planet was frozen, the so-called Snowball Earth, or more correctly, Icehouse Earth.  Earth Age 3826 (My).

A ‘golden’ spike that Internationally defines the lower boundary on the geologic time scale.  In 2004, it marked the recognition of a new chapter in Earth’s history.  The beginning (rocks above the marker) of the newly-recognised Ediacaran Period, 660 – 540 (My), containing fossils never before seen.  The rocks below the marker are from the Cryogenian Period.  Earth Age 3883 (My).

The finger points to an unusual rock layer: unusual in that the particles within it are all angular and varied in size.  Interpreted only in 1986, this layer is an ejecta layer from a bolide (meteorite) impact at 590 (My), that created a 50+ kilometre wide crater (20-30 mi) now eroded to a salt lake, Lake Acraman.  This sample of the ejecta layer is about 300 kilometres (190 mi) distant from the crater.  Earth Age 3953 (My).

This fossil-filled rock was formed at 525 (My), Earth Age 4018 (My).  The fossil is an Archaeocyath, meaning ‘ancient cup’.  The circular sections are of a barrel shaped body.  The Archaeocyath are a now-extinct group of marine sponges that were important in forming the first reefs on Earth.  The location of these fossils has been recommended as a World Heritage site.

Back in Northern Australia.  This cliff bordering the Fitzroy River appears unusual in shape, colour, and layering.  Dated at 350 (My), Earth Age 4193 (My), the cliff was once part of a large, fossil-rich, reef.  Known as the Kimberley Fossil Reef, it is horseshoe-shaped and hundreds of kilometres in extent.  Nearby, there are numerous areas of high-quality, fish fossils, the first back-boned animal.  Until then, all land surfaces were lifeless, but from this time on, green (photosynthesizing) plants began invading the land and changing the colour of planet Earth.

Shark Bay, Western Australia, declared a World Heritage site to preserve a large populations of living stromatolites.  This very small sample captures their variation in area and shape, but notice the uniform height determined by tidal variation.  It is a way of living – a signature of Life – that has persisted for at least 3400 (My).  Earth age 4543 (My).