Lithospheric Dehumidifier

A few years ago a friend decided to demolish his old house due to extensive and expensive water damage to the ground floor. 

Could this be the explanation for the damage?

xkcd comics

A spanking new apartment building now stands at the spot of the old bungalow. There are no signs of any water damage so far. A giant lithospheric dehumidifier may have been used during construction.

There is no end to the add on and perks developers promise these days.

The Making Of Iceland

Committees are underappreciated. 

xkcd comics.

Happy New Year everyone! 

Saved By A Projection

I just had to share this wonderfully imaginative piece of science fiction from xkcd comics.

Using map projections to alter our perception of geography is an old trick.

Reverend William Buckland's Pie Crust

I came across this delightful passage in Elsa Panciroli's book, Beasts Before Us: The Untold Story of Mammal Origins and Evolution.

Naturalists exploring southern Scotland in the early nineteenth century came across some intriguing looking footprints impressed in red sandstone in a quarry at Corncockle Muir. The geologist Reverend Henry Duncan described these footprints and send some casts to the Reverend William Buckland who was making a name for himself in the emerging field of geology. The thinking was that these tracks were most likely made by crocodiles and turtles. Reverend Buckland came up with a clever way to test this idea. 

From Elsa Panciroli's book-

'Ist I made a crocodile walk over soft pye-crust [sic]' he wrote in a letter to Duncan, 'and took impressions of his feet...[second] I made tortoises, of three distinct species, travel over pye-crust, and wet sand and soft-clay...' Buckland's wife supplied the pie-crust and Buckland supplied the tortoises. Where the crocodiles came from is unclear, but as Buckland had a penchant for eating them he probably also had access to  live ones. The results : the marks matched the tortoises. He concluded, 'though I cannot identify them with any of the living species.... the form of the footsteps of a modern tortoise corresponds sufficiently well.... so I conceive your wild tortoises of the red sandstone age would move with more activity and speed... than my dull torpid prisoners.'

It was understood much later that these footprints in sand from Permian times (299 -252 million years ago) were made by early Therapsids from which arose the mammalian lineage. 

I am really enjoying this book! 

Eastern Ghats- The New Kid On The Block

We who live in the Deccan Volcanic Province in and near about the Western Ghats generally look down upon the Eastern Ghats. Call them the poor man's mountains. Point out that the Eastern ranges have a more gentle topographic profile than the Western ranges. We smirk at the lack of spectacular escarpments, narrow gorges and the mesas and pinnacles.

But, when it comes to geology, the Eastern Ghats more than holds its own. In fact, it has a much more complicated and interesting geologic history than the Western Ghats, at least the Deccan Volcanic part of the Western Ghats.

The Deccan Volcanic part of the Western Ghats is an elevated plateau which formed by the piling up of lava 66 million years ago and which since has been dissected by rivers, forming gorges, narrow valleys, and high relief. The edge of this plateau is the Western Ghat escarpment. The Eastern Ghats on the other hand is an ancient orogenic belt which formed by the collision between crustal blocks, resulting in the formation of fold mountains.

The map below shows the broad geology of the Eastern Ghat with the inset showing its location within the Indian continent.

Source: Relative Chronology in High-Grade Crystalline Terrain of the Eastern Ghats, India: New Insights: Samarendra Bhattacharya, Rajib Kar, Amit Kumar Saw, Prasanta Das 2011.

The Eastern Ghats is a Late Archean to Proterozoic age crustal block that has evolved through long and multiple episodes of magmatism, metamorphism and deformation.  It contains rocks ranging in age from 2. 9 billion years to 900 million years old. The rocks have some of the coolest names in petrology; charnockites and enderbites, khondalites, anorthosites and syenites along with granitic rocks and  sedimentary rocks like quartzites. Charnockites (and enderbites) and khondalites are granulite grade metamorphic rocks, i.e. they formed at very high temperatures of around 900-950 deg C by transformation of older igneous and sedimentary rocks respectively. Anorthosite is an igneous rock made up almost entirely of plagioclase feldspar. Syenite is also an igneous rock containing potassium and sodium rich feldspars with no or little quartz.

The interesting part is that the Eastern Ghat block was not part of India when these rocks formed. It may have been an independent block in the Archean (more than 2. 5 billion years ago), but at some point it became part of a larger block that is now the Antarctic continent. This region then underwent magmatism around 1.7-1.6 billion years ago, an episode of granulite metamorphism around 1.6 billion years ago in its southern regions, followed by sedimentary basin formation around 1.3 to 1.2 billion years ago. These sediments were then buried, intruded by magmas like syenites,  and subjected to another episode of granulite grade metamorphism around 1.2 to 1 billion years ago. This last episode of metamorphism and deformation was a result of continental movements and collisions related to the formation of the Rodinia Supercontinent.

When did the Eastern Ghats become part of India? Geologists have timed that event to around 500 million years ago, part of the assembly of Gondwanaland.

How did they figure that out? When the Eastern Ghat terrain collided with India in the Bastar region, it caused the Baster region crust to be buried to great depths resulting in the partial melting of that crust. Radiogenic dating of minerals titanite and zircon, which formed in these new melts, give an age of around 500 million years to this melting event.

I love it when these big ideas are depicted in simple and clean diagrams. Below is a graphic that shows the separation of the Eastern Ghat terrain from its conjugate Antarctica block called the Rayner Complex.

Source: Eastern Ghats Province (India)–Rayner Complex (Antarctica) accretion: Timing the event- Pritam Nasipuri, F. Corfu, and A. Bhattacharya 2018

Two scenarios are shown. The upper panel shows a composite Eastern Ghat Province-Rayner Complex colliding with the Greater Indian landmass around 500 million years ago, followed by a breaking away of the Rayner Complex. The lower panel shows that the Eastern Ghat Province had broken away from the Rayner Complex by 800 million years ago. It then collided with India around 500 million years ago.

The Indian continent was put together by the collision and welding of several smaller continental blocks, namely Dharwar, Aravalli, Bundelkhand, Bastar and Singbhum. This assembly took place between 2 billion and 1 billion years ago.

The Eastern Ghat block was the last to join India. As recent work suggests, as late as 500 million years ago.

Lamarckism Continues To Cast A Shadow Over The Archaeological Survey Of India

A friend mentioned that she was planning to visit the famous rock shelters at Bhimbetka in Madhya Pradesh. These sandstone caves are famous for rock art and stone tools ranging in age from Paleolithic to more recent times. The site is looked after by the Archaeological Survey of India (ASI).

I remembered my own trip there over three years ago. Diving into my picture collection I  came up with this gem. This plaque was in front of a cave where Paleolithic stone tools had been found. It describes the grand story of human evolution.

Underlined in yellow is the explanation for the evolution of our dexterous hands. I am not highlighting the language but the very Lamarckian-sounding mechanism. If the claim is that hands capable of making sophisticated tools evolved just by continuous handling of stone, then this is evolution occurring through inheritance of acquired characteristics. Just like a blacksmith passing on his musculature to his children. This is not a viable mechanism of evolution. Physiological changes acquired due to a life experience are not passed on to progeny. Our gametes are sequestered from our somatic cells. I strongly suspect that a lot of people still conflate inheritance of acquired characters with natural selection.

The very first sentence "Millions of  years after Ramapithecus the species Australopethecus and its subspecies came into existence" is confusing too.  As is another plaque which shows the classic linear march of hominin evolution from a more primitive looking ape to modern humans. In it, Ramapithecus appears to be an early ancestor of humans.

Australopithecus (genus, not species), did appear millions of years after Ramapithecus, but there is no ancestor-descendant relationship between the two. Ramapithecus was initially identified as a Miocene ape and a possible ancestor of humans. Its range was the Himalaya foothills, leading to some excitement that the human family roots can be traced to the Indian subcontinent. More fossil finds have changed this early interpretation. Ramapithecus is not even considered a valid taxon anymore. The fossils named Ramapithecus are now subsumed under the genus Sivapithecus. This latter genus includes a great variety of Asian ape species. The lineage is more closely related to the ancestors of the Orangutan and not to living African apes and the hominin family.

This is just a poor show by the ASI. They need to urgently upgrade the information they are providing the public.

Jesus n Mo: Those Furry Eskimos

They nail it every time!

Absence of furry "eskimos" is an actual argument touted against evolution! :)

Bias In The Spider Fossil Record

Loved this one from xkcd comics:

A World Made Of Coccolithophores And Foraminifera

A tweet by Andrew Alden sent me to this paper:

Factors regulating the Great Calcite Belt in the Southern Ocean and its biogeochemical significance- William Balch et al 2016

The Great Calcite Belt (GCB) is a region of elevated surface reflectance in the Southern Ocean (SO) covering ~16% of the global ocean and is thought to result from elevated, seasonal concentrations of coccolithophores. Here we describe field observations and experiments from two cruises that crossed the GCB in the Atlantic and Indian sectors of the SO. We confirm the presence of coccolithophores, their coccoliths, and associated optical scattering, located primarily in the region of the subtropical, Agulhas, and Subantarctic frontal regions.

Great Calcite Belt, Coccolithophores - tiny unicellular phytoplankton covering 16% of the global ocean...

how can one not go back to that wonderful essay by Stephen Jay Gould on Crazy Old Randolph Kirkpatrick

Kirkpatrick was an eccentric natural historian who in the early 1900's  proposed an outlandish theory that the earth was made up of Nummulites, a group of the protist organism Foraminifera. He saw nummulites everywhere he looked, in the global ocean, the entire crust, even in igneous rocks. He concluded that the earth's shell must have been made up of nummulites., Heat from the earth's interior fusing them together and fluids injecting them with silica to form the hard rock we recognize as the igneous variety..

Rocks are sometimes classified as fossiliferous and unfossiliferous, but all are fossiliferous... Really, then, there is, broadly speaking, one rock..... The lithosphere is veritably a silicated nummulosphere.

He thought that nummulites were one of earth's earliest creatures and gave them the name Eozoon and with a flourish wrote:

"After the discovery of the nummulitic nature of nearly the whole island of Porto Santo, of the buildings. wine presses, soil, etc., the name Eozoon portosantum seemed fitting one for the fossils. When the igneous rocks of Madeira were likewise found to be nummulitic, Eozoon atlanticum seemed a more fitting name."

"If Eozoon, after taking in the world, had sighed for more worlds to conquer, its fortunes would have surpassed those of Alexander, for its desires would have been realized. When the empire of the nummulites was found to extend to space a final alteration of name to Eozoon universum apparently became necessary."

We remain trapped in perceiving our world as one teeming with large multicellular animals. But the world is much more. It is a world full of microbes and unicellular eukaryotes too. These creatures occurs in numbers that dwarf our metazoan presence. They are ubiquitous in the surface ocean layers, in the sunlight plankton zone, and their skeletons blanket the depths, creating a layer of ooze covering the sea bed. Their life and evolutionary cycles modulate in large part the global carbon cycle.

Randolph Kirpatrick in his feverish imagination saw an empire of Nummulites.. not too far fetched from the Great Calcite Belt of Coccolithophores covering 16% of the global ocean.

On Being On The Lower Rungs Of Science Hierarchy

This made me chuckle: On being a mycologist from Adam Rogers- Proof: The Science of Booze

"It was something even I, an undergraduate who didn't know anything could do", Scott says. " I could go out there and look for stuff" In the space of one anecdote, Scott had become a mycologist. You think you were an iconoclast in college? Try being a tall, gay, banjo-playing fungus major with a microscope in  your dorm  room,  walls decorated with fungal family trees you drew yourself".

and.. this on perceived scientific hierarchy:

Magnified fungi look like alien plants from a 1930s pulp sci-fi magazine cover, or a Dr. Suess illustration rendered by Pixar. Its a weird landscape, not to everyone's taste. 'If you found a new deer, you'd be on the cover of Nature," says John Taylor, a mycologist at UC Berkeley. "If you find a new fungus, you're in the middle pages of Mycotaxon. But we're not bitter".

That last sentiment reminded me of a conversation I had a long time ago. It was during my M.Sc field training week in Central  India. We were walking back to  camp after a long day's tramp through forests and stream beds. The conversation turned to career choices and the merits and excitement  of getting into a science career. One faculty with us reminded us not to expect attention. Most scientists  will live through  a low profile career.  They will meet a small circle of colleagues and peers. Their papers  will be read by a few  handful of others. You need  to accept this and be satisfied that your  choice and your work is adding  incrementally to our knowledge. Don't expect revolutions.

Is there a division in geology between glamorous and less weighty fields? Again, I  am reminded of the situation during my graduate days at Pune University. The geology department there grew out of a hard rock petrology tradition. There were experts galore on igneous, metamorphic rocks, structure and tectonics and field mapping. Sedimentologists studying hard, consolidated, heavily diagenetically altered and cemented rocks were considered real geologists. Working on unconsolidated Quaternary sediments and landforms was looked down upon. Even worse was if you were in the "environmental" field. Dibbling  dabbling with water samples was just not worth the trouble! It's not hard core geology- was the majority voice.

But times are changing.  The recent impetus in studying climate change means that Quaternary sediments and the secrets they hold about past climates and sea level changes is a hot area of research. So are fields like environmental geochemistry, spurred by increasing social awareness and a tougher regulatory regime, geared towards understanding the myriad pollution problems we face today. They attract funding from government grants and younger faculty and scientists are seizing the opportunity and launching their careers on *shudder* ..the unconsolidated stuff..

Creationist Version Of Neanderthal Human Interbreeding

via The Panda's Thumb..

Had to put this up. Apparently creationists have their own take on the recent findings that Neanderthals interbreed with modern humans.

Svante Paabo who has led the effort to sequence the Neanderthal genome and has a popular book about it writes:

There were many others who were interested in the Neanderthal genome – perhaps most surprisingly, some fundamentalist Christians in the United States. A few months after our paper appeared, I met Nicholas J. Matzke, a doctoral candidate at the Center for Theoretical Evolutionary Genomics at UC Berkeley. Unbeknownst to me and the other authors, our paper had apparently caused quite a flurry of discussion in the creationist community. Nick explained to me that creationists come in two varieties. First, there are “young-earth creationists,” who believe that the earth, the heavens, and all life were created by direct acts of God sometime between 5,700 and 10,000 years ago. They tend to consider Neanderthals as “fully human,” sometimes saying they were another, now extinct “race” that was scattered after the fall of the Tower of Babel. As a consequence, young-earth creationists had no problem with our finding that Neanderthals and modern humans had mixed. Then there are “old-earth creationists,” who accept that the earth is old but reject evolution by natural, nondivine means. One major old-earth ministry is “Reasons to Believe,” headed by a Hugh Ross. He believes that modern humans were specially created around 50,000 years ago and that Neanderthals weren’t humans, but animals. Ross and other old-earth creationists didn’t like the finding that Neanderthals and modern humans had mixed. Nick sent me a transcript from a radio show in which he [meaning Hugh Ross] commented on our work, saying interbreeding was predictable “because the story of Genesis is early humanity getting into exceptionally wicked behavior practices,” and that God may have had to “forcibly scatter humanity over the face of the Earth” to stop this kind of interbreeding, which he compared to “animal bestiality.”

Clearly our paper was reaching a broader audience than we had ever imagined.

Aha.. so that's why humans colonized the entire planet. It was punishment for engaging in bestiality.

There is also a transcript of a bizarre conversation between creationists trying to answer the deep question that while there are references in scripture of God destroying angel-human hybrids, Neanderthal -human hybrids eventually died out too, leaving humans to be with humans only.

Sunday Humor: Rugby And Geology Don't Go Together

I ran into a friend after many years. Her son used to come to our academy for soccer and rugby coaching. She mentioned that a common friend had recently put up a link to my blog on his Facebook wall and after reading a few of my posts had showed my blog to her son, reminding him who I was.

Her son who is now a teenager exclaimed.. "but Mama how is it that a rugby coach can be clever enough to write a geology blog?"

My friend is now trying to persuade her son to meet me again. I on my part have promised to take him and his friends to a trip to the local geology museum.

Maybe I can convince him that sometimes sports, jocks and rocks do go together.

Found It! Memories Of Early Days Of Geology Education

A mouse got in to an old book shelf a few days ago. Panicky cleaning up ensued and there from the back out came a treasure.. (not the mouse.. it ran away)

This well worn copy of the Petrology classic was my introduction to rocks when I started taking geology classes during my first year B.Sc. The book written in the late 1920's was still being used in the mid late 1980's and early 1990's! There were about a hundred of us packed in the intro geology class with the instructor drawing rough sketches on the black board and explaining the basics of the interior of the earth and the three primary types of rocks, igneous, sedimentary and metamorphic.

I quickly gave up of Tyrrell and turned to other sources.. but those afternoons I do remember.. I knew that after two years of high school not knowing what I was going to do in life that I was on to something special. Geology has stayed with me ever since.

My decision to take up geology had interesting reactions from family and friends. My immediate family, mom, dad, sister and my grandfather completely supported me. Others were less convinced. I was not very good at math so engineering was out. I was not very good at biology so medicine was out. These two were the prestige courses for students.. they had high social standing and these degrees lead to high income careers. Taking a degree in pure sciences was basically admitting that you hadn't done well in the exams and thus could not hack it in the tough technical degrees.

Getting a B.Sc was for the duffers. But my relatives could not say that to me. So they were very sweet about it.." Geology?.. Yes you should take it.. someone has to do it..  we need oil.. minerals"... blah blah blah..

This condescending attitude continued until I got a scholarship to go to the U.S. Then snobbery took over. Getting scholarships to the U.S was again something that mostly only students from technical colleges like the IIT's were supposed to be successful at. Suddenly I was on par with them. Support for me was now because I had at last brought some prestige to the extended family.. "my nephew got a scholarship to the U.S... for a PhD"..

That I had really become passionate about geology and it meant to me more than scholarships and going to the U.S. completely escaped them.

Geopathic Stresses Behind Indian Expressway Mishaps

Ok..something lighthearted.. but this really was published as a serious article in the newspaper DNA:

Geopathic stress or simply “bad energies” are harmful radiation arising from the depths of our planet. According to geophysicists, there is a natural magnetic field on the earth’s surface to which all beings are acclimatised. Geopathic stress arises when this natural magnetic field of the earth is distorted by weak radiations generated by underground streams of water, sewers, drains, certain mineral concentrations, fault lines and underground cavities. This stress impact on the physiological condition of drivers leading to critical errors while driving. However, awareness about the existence of this factor can help drivers, experts say.

... Tyres bursting at this spot are the cause of a major number of accidents. The stretch has numerous cracks in the road, which are affecting vehicles. These cracks are due to hollow spots, which are generated due to tectonic movements and cannot be repaired by re-tarring, the earth at these high geopathic stress spots shifts periodically in intervals.

An explanation by people who dabble in Vastu.. which studies among other things the "energy" being emitted by the earth. This "energy" is manifest only to a select few.. alas the world's physicists have been unable to measure it and understand its nature.

Geopathic stress levels were determined by a rigorous survey and using sophisticated measurements along all the accident spots on the highway. Apparently the high "geopathic stresses" are indicated by vigorous movement of a dowsing rod like equipment. Geopathic stresses are ranked on a scale known as the Lecher scale from 1 to 15. Spots on this highway go up to 11. 2 on the Lecher.  The greater the movement of the dowsing rod - which a person holds in their hand while surveying- the higher the "geopathic stress". The scale was established after assiduously applying a correction for the "hand tremble syndrome" that seems to afflict practitioners of this art (I made up the last bit).

I am learning a lot!

As a geologist I am not really aware of the earth's magnetic field being distorted by underground sewers and such and that "distortions" will suddenly affect human physiology to the point of being disoriented. Claims that there are cracks in the road due to tectonic movements are also false... "Uhh.. we would have noticed the earthquake?" Movements large enough to generate cracks in the road will have registered on seismometers.. no such largish earthquake damage has been reported by geologists in this part of the country..

After all this hooey.. the Vastuworld team does give admirable advice:

...one major help in reducing the accident rate on the expressway would be that the drivers would still have to drive safely and without breaking the rules.

 Now..the day that happens in India.. the earth will rumble mightily.. right up to 15 on the Lecher scale !

Going Hiking In Pangaean India

I have been thinking unhappy thoughts ever since I came upon this map of Pangaea with today's political boundaries overlaid on it.

Where would I have going hiking in Pangaean India?

1) The Himalayas, crown jewel of hikers arose begining early Cenozoic and reached their bewitching heights in the mid Miocene -Pliocene.

2) The Western Ghats, the poor man's Himalayas, arose in the Cenozoic too after the breakup of India from Madagascar (88 mya) and Seychelles (66 mya). They represent heights reached due to an initial high rift flank, amplified by denudational isostacy and crustal upwarp due to intraplate stresses propagated southwards from the Himalayan collisional zone.

3) The Eastern Ghats, a line of mountains parallel to the east coast of India also arose much later than Pangaea forming during and after the breakup of India with Antarctica about 130 mya.

4) The Vindhyan and Satpura mountains in central India are composed of Proterozoic and late Paleozoic -Mesozoic rocks resp. but much of today's relief also represents topography rejuvenated since mid Cenozoic, ultimately related to stresses from the Himalayan collision.

5) The Aravalli mountains in Rajasthan is a Proterozoic orogenic belt but probably didn't have much topography during Pangaean times.

For most of the time period from Cambrian to Carboniferous the Indian shield was a tectonically stable area. Pangaean India was a place where a vast peneplain had developed over most of the Indian shield in response to long lasting denudation. This cycle of deep weathering and erosion lasting tens to a hundred million years would have stripped and ultimately flattened the Aravalli and south Indian orogenic mountains, exposing mountain roots and lower crustal rocks like granulites and charnokites. The result would have been a subdued topography with a flat horizon as far as the eye can see, occasionally interrupted by gentle rolling hillocks made up of more resistant lithologies like quartzites and charnokites. 

Subsequent episodes of uplift and erosion has destroyed this flat topographic surface from all over the Indian peninsular region but some remnants of this peneplain termed the Gondwana surface can be observed at around 2400 m mantling the granulites of south India around the popular hill stations of Ooty and Kodaikanal in the Nilgiri mountains.  It has been lifted to these heights during Cenozoic uplift of the Western Ghats.

The only places of considerable relief would have been the emerging Permo-Triassic rift basins of the Satpura, Pranhita Godavari and Mahanadi belts in the central and eastern part of  country. A horst graben structure would have resulting in a ridge and flat valley type topography. Not particularly attractive for a challenging hike. Plus it was really swampy and hot in those rift basins.

I wouldn't have liked to live in Pangaean India. I am too spoilt by views like this one, which appeared only in the Miocene.

Photo: Nanda Devi and Namik Glacier in the Kumaon Himalayas, November 2012.

Sunday Humor: A Professor's Prayer

Another classic from PHD comics:

"Submerged Continent" Story Trending For The Wrong Reasons

It does seem so judging by the comment stream of this article by Akshat Rathi which appeared in The Hindu last week. The article is currently in the most popular list of the Sci-Tech section of The Hindu.

"This could be another malefic design to make tamils believe they belong to different continent. As the validity of 75 yrs old dravidian myth is busted by science dna researches and rationale thinking. This could be yet another attempt to confuse south people".

from:  Periyar  

"It is interesting how scientist sometime make outlandish claims with no certainty of counter proofs. In fact it all depends which group you belong to, dominant or struggling, majority view which is stupid or minority non-peer view but sensible. So here we go again. The only certainty is that the world map did not look like today millions of years ago. There are unexplained artifacts many millions of years from different parts of the world which are neither explained or frankly admitted to be un-explainable. The reason being the Scientists calling the shots cannot eat humble pie. There are hundreds if not thousands of such artifacts. Some have conveniently disappeared to stop embarrassment for scientists. And then there are myths and legends, Ramayana and MahaBharat and 'in peoples memories'".

from:  Politenotpc 

"There was an article several days before that Australian aborgines share the same DNA as the rest of South India. So hypothetically speaking their ancestors would have traveled centuries before to Australia by land. impressive findings these.."

from:  Manoj 

"I was fascinated to read about the discovery of this new continent and its location so close to India.I was then wondering whether it could be the JAMBUDWIPA of yore which we repeatedly recite in Vedic chants."

from:  kumar

 

People are relating the submerged continent to events that may have taken place in human history with some nationalist pride and suspicions of scientists thrown in as well :)

The finding off course belongs to deep geological history.

Geophysical data indicated that the lithosphere in this region is thicker than what would be expected in an oceanic basin made up of basaltic crust alone. And zircons collected from xenocrysts (fragment of a foreign crystal) within lavas on the island of Mauritius gave a Proterozoic age. The lavas of Mauritius which contained these zircons were about 9-10 million years old. That suggested that these zircons belonged to very ancient continental fragment beneath Mauritius from which they were broken of and brought to the surface by younger lavas.

The continent is a smaller piece of Gondwanaland that separated from Madagascar about 60-80 million years ago as rifting between larger pieces of Gondwanaland (Madagascar and India) stretched and thinned the crust opening up an oceanic basin.  Prolific basaltic volcanism later covered this continental fragment . So, there never was a land connection across the Indian Ocean between India and other continents in recent geological history. Some of these continental fragments may have submerged below sea level much earlier and some would have appeared as small islands in the area between Mauritius and Seychelles - well to the south of India - before being covered by lava several millions of years before the presence of any humans on the Indian subcontinent.

But the allure of the "lost continent" endures.

The Real Reason Behind The Santa Cruz Islands Earthquake

From Jesus and Mo..

And here is the less likely explanation.

Plate Tectonics: The World Is A Chicken

Had to put this up.. via WEIT:

Sunday Humor: Young Earth Creationists And Oxygen Levels

I get responses to my blog posts from students, geology and nature lovers and even journalists asking questions, requesting papers and sometimes just to chat.

Occasionally I get comments like this one recently left on my blog post Early Homo Leaves Modern Footprints:

hasn't anyone ever stopped to think that, maybe when that giant flood happened a long time ago (10,00 years?) that maybe, just maybe, due to the serious compression of heat, oxygen, and pressure, that that is why we have fossils and remains? also, before "the flood" the oxygen level in the air was significantly higher than afterward. so our modern "technology" that measures how much oxygen something has been exposed to, is merely based on the level of oxygen that is currently in the air. not what the levels were long ago. thus, those who claim the earth is billions or millions of years old...is mistaken due to the lack of knowledge of the oxygen levels before "the flood".

Feel free to dissect this nonsense :)

The four glaring problems:

1) There is no evidence of "the flood" which in young earth creationist language means a global flood which deposited all the rocks seen on the surface today.

2) rocks exposed to "serious compression of heat, oxygen and pressure" would destroy organic remains, not provide conditions for fossilization.

3) There is no evidence that oxygen levels a few thousand years ago were much higher than today.

4) We don't rely on the levels of oxygen in the atmosphere to figure out how old the earth is.

One good thing about comments like these is that I get tempted to dig into the literature to read more on the fundamentals. I found two good sources on the geologic history of atmospheric oxygen. Atmospheric oxygen over Phanerozoic time by Robert Berner and a chapter on Oxygen Through Time in Out of Thin Air: Dinosaurs, Birds, and Earth's Ancient Atmosphere.