The curious case about seemingly endless energy

/ 17/10/2021

The most powerful geothermal well so far, the Icelandic Deep Drilling Project. Photograph borrowed from the Mannvit engineering company.

How’s that for a humdinger of a clickbait headline?

As clickbaity as it might seem, it is still true, but I freely admit that it comes with a couple of hippopotamus sized caveats.

Firstly, I should probably state that this article is about geology, geophysics and tectonic plates, and not as such about volcanoes, I do though hope that you my beloved reader will accept this little digression of mine.

Secondly, I should point out that I am a geophysicist working with volcanoes for a day job, specifically in regards of geothermal energy. For the last decade and a half, I have written dry reports to governments about the wonders of drilling large holes into volcanoes to extract energy.

It will probably not surprise anyone that governments enjoy dry reports, but not so much coughing up the money to build modern geothermal plants.

 

The background

Geothermal Power Plant at Krafla Volcano in Iceland, the beautiful picture is borrowed from Wikimedia and was taken by Ásgeir Eggertsson.

Normal bog-standard geothermal energy comes in three distinct flavours of extraction, the most common is when a household drill a shallow borehole in their garden to extract heat out of the ground. This is quite common in the northern part of the world, well at least in Sweden.

The next one is drilling into a geothermal field to extract hot water or steam for space heating and electricity production. Depending on the size of the field and your ambition you can extract anything from a few kilowatts to a few hundred megawatts.

This is done by using drilling techniques developed at the end of the 19th century during the initial oil-boom in the United States. In other words, a shallow hole, straight down to shallow or intermediate depth.

So far, the available extracted energy is depressingly limited.

The third version is far more exciting, and that is to drill into, or next to, a magma reservoir in an active volcano. This has already been done by the Icelandic Deep Drilling Project, and there is at least one large scale power-plant being in the permitting stage using this technique (caveat is here applied, I am involved in that one).

If you look at the drilling side, we are now well into the state-of-the-art techniques developed by the oil and gas industry during the last 100 years or so.

This form of geothermal energy will transform volcano rich countries and has the potential of solving roughly ten percent of the worlds current electricity needs in a sustainable and renewable way. Problem is that it is just not enough.

To meet the Paris Agreement, we need to replace all electricity produced by coal, gas, and oil-powered plants. And that is a whopping 61 percent to replace.

To compound the problem, if we all are good little ecological people and go electric when driving, then we need a further 36 percent more electricity than what is currently produced in the world.

On top of that the worlds electricity consumption is increasing with 5 percent per year as the developing world is catching up to the industrialized part of the world.

The ten percent that classical, and not so classical, geothermal energy can produce is now at best a partial solution of the problem.

Even with all the current hydropower electricity in the world, and a monster-sized expansion of wind and solar-power, it is not enough. Grid-storage and smart-grids are also only partial solutions to the problem.

Even with all these good and nice solutions we do not reach the target, we already notice this as rising electricity prices across Europe and the United States, and those prices will skyrocket in the next couple of decades.

Now some will jump up out of their chairs and scream “NUCLEAR!” But before you do that, please explain first how we will pay the 13 trillion (and counting) dollar bill that we have already accrued to clean up the mess that it has already produced. You can’t? Well, I sure as heck can’t either, so sit down and we will continue with geothermal energy which is what this article is all about.

 

The fourth way

This drillbit is all that remains from the record-breaking Bertha Rogers Hole. The drill-bit is to date the deepest drillbit fished out of a hole. I borrowed this picture from the East Texas Oil Museum.

In 1974 the Lone Star Production Company drilled the 1-27 Bertha Rogers Hole in Washita County, Oklahoma. At 9 583 meters depth they had not found any hydrocarbons, instead they hit molten sulphur that solidified around the drill-bit and the drill-pipe twisted off.

This borehole, and not Operation Mohole, set off a “drilling into the crust cold-war race”. Enter the Soviet Union and their Kol’skaya sverkhglubokaya skvazhina SG-3, more commonly known as the Kola Superdeep Borehole.

At 12 262 metres depth the (by now) Russians ran out of money, and the project was permanently shut down in 1994.

In 1987 Germany got into the drilling-race and the German Continental Drilling Program succeeded with a 9101-meter-deep hole into the ground.

As with all other cold war projects it was a game of brinkmanship, with just a thin wail of science draped on top to make it seem less ridiculous, at no point was geothermal energy a part of the equation.

There was thought heaps of data collected, and in that data, we find a couple of nice nuggets of golden information. In fact, they solved our electricity crisis without even realising it, or even caring about any future use of the collected information.

 

Crustal geothermal energy

Drill-tower from the Kola Superdeep Hole. Picture taken by Andre Belozeroff, and is borrowed from WikiMedia Commons.

For geothermal energy to work you need a surprisingly small temperature differential if you are just planning to warm up your house via a heat-exchanger.

If you wish to produce electricity more heat is definitely better. The gold standard is the temperature for dry steam found at a minimum of 275 Celsius at a pressure of 59.6 Bar. If the temperature is lower the steam will contain water-droplets that will damage the turbine-blades, and instead one must use either steam-cleaners or heat-converters and a lower-temperature superheated steam agent like ammonia. For any itinerant engineers, I know that I simplified this a lot, you guys aren’t the target audience in this context.

Bertha Rogers was drilled by oil-well roughneck’s working on a budget, so they did not write down long-winded reports about their findings, the just wanted black stuff to squirt out of the ground. Regardless, we still get a couple of nuggets out of them.

The first of those nuggets is that the absolute minimum temperature in the borehole at 9 583 metres was 115.2 Celsius, it was probably higher than that, but we only know that the sulphur was molten. They never wrote down the actual temperature to my utter dismay.

The second nugget is that they proved that even with the simpler technology of the 1970s it was feasible to drill that deep on a budget that would be reasonable if you are intending to drill many holes at the same place.

The budgeting issue will become important as a comparison to the next two boreholes.

The Kola Superdeep Borehole had no budget, instead the Soviet Union poured money into it, developing new methods of drilling, new record-breaking drill-rigs, and the cost in the end helped to ruin them (together with the arms race, mismanagement, the space race, and so on).

The Soviet Union never stated the cost for drilling the hole, but it was to all points and purposes mind-boggling.

Another thing to remember here is that the intent of drilling into the dense and cold Baltic Shield was to not get heat-problems while drilling. For geothermal purposes this was a nightmare place to drill into.

We did though get loads of geologic knowledge for the money, for instance the believed transition point at 7km from granite to basalt turned out to not be true, instead it was found to be metamorphic granite causing an inversion.

We also learned that the rock beyond this point was thoroughly fractured and permeated with water causing the rock to behave in a plastic fashion. We also learned about microscopic plankton fossils at the depth of 6km.

But the important part in regards of geothermal energy is that the temperature gradient was different than expected. It was expected that the coldest piece of crust known to mankind would be 100 Celsius at 12 kilometres depth, instead the readily available deep water was 180 Celsius.

At those pressure that temperature equates to 5MW of extractable energy. As a single 12km deep hole that is obviously not economically feasible even on the stingiest oil-drilling budget, but it is extremely interesting none the less, since it is a worst-case scenario.

 

The Hole of Germany

Drilltower at the Hole of Germany at the easy to pronounce Windischeneschenbach. Photography borrowed from Wikimedia Commons, taken by JW Pilsak.

If we now move onwards to the Hole of Germany, officially known as the German Continental Deep Drilling Program at Windischeschenbach, we find the same fractured plastic geology permeated by hot water. Here we do know the cost, an eye-watering amount of 270 million Euro in 1987 value.

There they also tried to push in additional water into the rock, and it was found that it was possible to inject large quantities of water without losing well-integrity.

Before drilling the Germans constructed a drill-bit able to survive temperatures up to 300 Celsius, a temperature that was expected at depths of 10 to 14km. Instead, they found that temperature to be exceeded at 9.1km depth.

In geothermal terms they produced a well able to produce sustainably produce 12MW of electricity. That is borderline feasible on the famously stingy oil-drilling budget for a single well.

 

A thought experiment

Let us now formulate a hypothetic story. One morning Vladimir Putin wakes up after having nightmares about global warming. Covered in cold sweat from his nightmare he decides to solve this problem once and for all with geothermal energy.

He then picks up the phone and orders Gazprom to drill a geothermal well for every single square kilometre of Russia. For good measure he explains that if they do not comply, he will Putinate all of them. Happily having solved the problem he goes back to a restful sleep filled with far nicer dreams about the upcoming Russian Electricity-dominated world.

As ludicrous as this idea might seem we should do the math of this insanity to see if it would solve the problem, let us not bother about pesky economics at this stage though.

Let us here assume that Russia is as uniformly cold underground as the Baltic shield is on the Kola Peninsula.

First of all, Russia is big, 17.13 million square kilometres big. At 5MW per square kilometre this equates to 85 650 000MW, or 85 650GW, or 85.65TW. The combined production of electricity in the world is currently roughly 28TW.

Dang, did our hypothetical Putin just save the world with ample margin to spare? Yes and no, and at the same time.

You would obviously need 85 million 5MW power-plants, and the grid-infrastructure to connect all of them. The cost for all of that would be so high that no feasible electricity price would ever merit that, not even if governments subsidized this loony idea.

 

Making a more feasible case

Let us now try to make economically viable case of Kola-holes. After all, the hypothetical people at Gazprom are the best in the world at drilling oil and gas-wells on a budget, and they learned heaps of stuff from the original Kola-hole.

First, they would use multi-pad drilling. This is when you drill several boreholes tightly together from the same derrick-pad. They would probably spud up to 8 boreholes without the extremely costly dismantling, moving, and then rebuilding the derrick for each hole.

These boreholes would then be made to drift outwards at an angle from each other to increase the uptake area of energy. A single hole would be 30-40 million Euro, with the multi-pad system we are now down to 20-25 million Euro per borehole.

Our hypothetical skilled Russians would now pull out the mother of all neat drilling-tricks. They would use each of the 8 boreholes as a parent-borehole down to 8km depth, from there they would split drill 3 side-holes from the parent-borehole, giving 4 extraction-wells per each of the eight surface boreholes on the pad. The deft Russians have now 32 wells on hand giving 20MW per parent-borehole, while at the same time having saved 24 kilometres of drilling for the same effect. By now each well is well below 15 million Euro.

Here economy of scale kicks in as they build a 160MW power-plant requiring a single grid-link instead of 32.

Even at this point it would require an extreme price per kWh for it to be feasible, or that a government would subsidize the project, but it is not impossibly far out if the alternative is all of us dying from the effects of global warming.

But the salient point here is that the Kola Superdeep Borehole was drilled at the worst possible place, at all other spots on earth you would either need to drill less deep, get more heat, or both improvements at the same time.

Even if we would cherry pick places with drilling depths of “only” 7km with the ability of producing supercritical fluid out of water (373 Celsius at 220 Bars), we would still have enough places to extract from to be economically viable at a cost of less than 10 Eurocent per kWh. Obviously the hotter and shorter the better.

And, if we run out of suitable continental crust, we can nick yet another trick from the rulebook written by oil-industry and go out into the much thinner oceanic crust.

 

Fringe benefits

Under this rusted steel plate lies one of the most important things on the planet, the Kola Superdeep Borehole. The birthplace of seemingly free and endless energy.
To me it is a very beautiful thing, but I guess not to that many others.
Photograph from Wikimedia Commons, taken by Rakot13.

There is yet another nugget hidden in the remnants of our three example boreholes. As they drilled the deeper parts of the boreholes, they noticed curious bubbling in the drill mud used as it was pushed up. At the Kola site they noted that it was so strong that it behaved like it was boiling.

At both the Kola site and at the Hole of Germany they duly tested the bubbly stuff and found that it was hydrogen that was bubbling up. At the site for the Bertha Rogers Hole, they just noted that the bubbly stuff burned, but was not useful methane, it is though quite likely to have been hydrogen since it did indeed burn.

At no site there was any excitement about the hydrogen, no particular follow-up research was done, and to this day we do not know what processes at such great depth produces hydrogen. After all, it was not the holy oil that was discovered, so why would they be interested?

Several decades later it is easy to scream out of frustration at the wasted opportunity for research into one of todays most promising energy sources.

Saving the planet is filled with these small little oversights.

 

Conclusion

No single solution will ever be able to solve our looming energy crisis. Instead, the solution is to be found in many different solutions, that if combined efficiently solves the problem.

In reality the answer is simple and complex at the same time. We need smart grids, grid-storage, solar-power, wind-power, hydropower and geothermal-power.

Of the options above, geothermal power is the best partner to wind and solar in roughly half of the world, and often in parts of the world struggling with getting enough electricity as it is. It is a technology that has the potential to change the world economy in the same way that oil did back in the day, but without destroying the planet while at it.

CARL REHNBERG

 

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672 thoughts on “The curious case about seemingly endless energy”

  2. I think, Carl, this is an inteesting approach.
    What I would like to know – this might come with the rhinoceros part – is whether transport is possible and how far?
    Precisely: Would it be possible to provide enough energy for Ethopia from the Afar triangle which would take some pressure from the dam, a nuisance for Egypt and Sudan? Or provide the South of Africa (including Tanzania and Kenia) which has a winter with heating and energy from say the volcanoes in Tanzania and Kenia?
    Same game for Chile and Argentina. And so on. So transport is my main question for a future piece.
    Aside from that there is no safe and clean energy. All of them have pitfalls.
    Another question (I read that sometimes): Is it possible that gigantic windparks reduce the Wind on the leeward side?

  3. Honestly, you should have thought that TV Canarias might pause to have a think about the positioning of their PiP. Or even consider not having it at all.

    Fortunately other feeds are available!

  5. I wonder what’s the petrological makeup of the lavas and ejecta in the ongoing eruption at Cumbre Vieja? Is it any different from the 1971 eruption?

    • Very nice catch, Randall!
      Curious how it doesn’t sound like a real lightning at all, but more like a large electric spark in a high voltage laboratory, having perhaps some 1 or 2 MV.
      I reckon this is due to the small size of the spark, which is leading to only a greatly limited volume of air emitting sound, as opposed to the many km of a common lightning bolt.

  12. The deeper quakes under La Palma, if occuring in series, are part of a long period event.
    I noticed that some days ago too, but wasn’t sure they took place simultaneously with the measured tremor.

    Today a new deep quake serie and a LP event on the charts does.
    La Palma tremor chart is far to busy to catch them proper, but La Gomera does and Tenerife station also, somewhat weaker.

    IGN Credits

    The earthquakes matching 14:12 – 14:24 (IGN list):

    es2021usjkr 22/10/2021 14:24:10 15:24:10 28.5611 -17.8406 33 3.0 mbLg NE FUENCALIENTE DE LA PALMA.IL
    es2021usjfj 22/10/2021 14:18:00 15:18:00 28.5619 -17.8194 34 3.2 mbLg SW VILLA DE MAZO.ILP
    es2021usjct 22/10/2021 14:15:06 15:15:06 28.5391 -17.8361 31 3.0 mbLg NE FUENCALIENTE DE LA PALMA.IL
    es2021usjbm 22/10/2021 14:13:27 15:13:27 28.5734 -17.8248 32 3.1 mbLg SW VILLA DE MAZO.ILP
    es2021usjao 22/10/2021 14:12:24 15:12:24 28.5525 -17.8273 28 2.9 mbLg NE FUENCALIENTE DE LA PALMA.IL

    • Good catch. Perhaps it’s the same mechanism that makes spasmodic (spiky) tremors in Greip and Pahala, although more powerful in this case.

    • What happens down there.
      Amateur alert!!! 😐

      I think the signal shows earthquakes (the largest are in the IGN list) and fluid movment as well.
      I am trying to visualize how the deformation takes place down there.

      The magma chambers may be small (I read) and form a complex in a large area, 10 km width perhaps.
      Depletion, lowering pressure causes gradual collapse in the complex, starting 28 km in this case and moving downward.

      It seems so logical, and besides if my view is true or not, it is fun to see such LP happening under La Palma. 🙂

  14. I see that the Smithsonian has marked off the Reykjanes peninsula volcanic eruption has officially ended- on 18th September 2021- just a wee day short of six months ( just in case am aware it could all start again soon.)

    • Yep, looks like FAF didn’t meke every effort to make that happen.
      At least it was longer than Holuhraun, though being much much weaker of course.

    • That means it is going to start again soon… FAF has habit of making geologist look foolish…

  15. Well interesting discussion, thanks for all the answers. Didn’t even know CAMP and NAMP were both on land instead of on the ocean and where the phenomens that drove breaking up of the plates.

    I saw someone mention hypercanes, i think they would be more common in Pangeae’s oceans, since if you have a supercontinent, you also have a superocean, especially battering the Eastern sides of Pangaea if you take into consideration modern circulations. The seas especially during Middle and Later Pangaea eras were also warmer than today’s. There would be a lot of fuel.

    But even if Pangaea was a supercontinent, i think on the prehistoric maps, there is still a part of China that was basically an island, part of an island or peninsula, but it’s exactly that kind of area that might have the most frequent hurricane impacts, and i also thought it was one of the more consistently wetter areas whereas other areas might have had much highly seasonal rainfall (and not only seasonal, but maybe also decadal / centennial droughts), and it’s rainfall might have been highly variable / unpredictable driven by monsoons which might have been vulnerable at times and hurricane trajectories / remnants. I think the area on the planet that resemble it the most today is the southern parts of the Arab Peninsula and the Arabian Sea / Persian Gulf and Gulf of Aden, as well as the Horn of Africa.

    • That’s right, China was supposedly consisting of two cratons back then, the North and the South China Craton sitting as a peninsula next to Siberia and an island underneath. Much of the West and the centre of China was formed when the Indian plate collided with the Eurasion plate. The cratons were situated between two oceans, Tehtys in the West and the Panthallassic, later Pacific, in the East.
      Once before, between 500 and 1000 mya, before even Laurasia and Gondwana, the predecessors of Pangaea had formed everything was sitting near Antarctica and between Antarctica and the Equator, even Baltica and Siberia.,

      Antarctica complained all the time feeling squeezed in. So everybody decided to divorce and to move up North, one after the other, and that’s exactly what they are still doing. It’s hard and takes a long time. The western route was busy. At some point they collided somewhere in the middle it seems. Antarctica has her own house now and sleeps contently under her ice sheet. Every now and then she has a cold and coughs in the West.

      Don’t take the second part too seriously. Earth invites to some stories.

  18. Someone on the chat said “It looks like a Hollywood volcano now.:

  20. Last 10 minues or so 3:53 am CET, a chip has developed in cone #3 where a part fell back into the pool and I am wondering if this erosion will continue and then redirect the spray down the north slope instead of just straight up, say a 20 deg angle or so?

    • 4:11 am CET parts of the cone falling in and creating a certain dark red smoke which I have seen from Galdingadlir which says major erosion occurring and pieces disintegrating

    • Lava rivers really running now, down in the town area, most lava I have ever seen now (so far) 4:19 am CET

      • 4:26 am CET and major flow of yellow hot lava going down north slope of cone, bigger than I have seen so far.

  21. Found this just now. Looks like Fagradalsfjall has got relatives.

    https://hiticeland.com/places_and_photos_from_iceland/eldborg-crater-sn%C3%A6fellsnes-peninsula

    https://www.facebook.com/photo/?fbid=10220535102028343&set=g.887053998798488

    Really the resemblance is quite striking. Seems these sorts of eruptions are not that rare just we havent seen them in recent years, except on Surtsey. I would expect we will see quite a lot more though from now on, with both Reykjanes and Snaefellsnes volcanic fields becoming volcanically active. Which is good, no ice or water to make them dangerous, and close proximity to Reykjavik.

    • Good catch Chad- it was good while it lasted-more to come- as long as it not near the Capital I’ll be happy with that.

    • Nice shape. Interesting idea.

      Btw, sometimes I strongly doubt the meteorite stuff, I think only the Iridium speaks for it.
      “Sometime between 80 and 60 million years ago, a large submarine plateau composed of unusually thick oceanic crust (possibly formed in the Pacific basin during initiation about 90 million years ago of a hot spot now located beneath the Galapagos-Islands) arrived at the subduction zone opposite the proto-Caribbean gulf. Because the oceanic plateau was too buoyant to be subducted, it began to override the proto-Caribbean gulf, carrying the Antilles volcanic arc on its prow.”

      I wouldn’t say there was nothing going on there in the sense of volcanism.
      From:
      https://www.britannica.com/place/North-America/Late-Mesozoic-and-Cenozoic-time

      • Add to this the structure of Lake Atitlán today. Imagine something like Atitlán, doubts should be valid.

      • Adding to my doubts is the fact that you find lots and lots of material about the medalists impact and Deccan Traps, and you have to browse back into Google to finally find something about volcanism in the area during that specific time. Finally I found something about Cuba. One passage:

        “The geology of Cuba is dominated by three lithotectonic associations, which reflect its evolution as a Cretaceous-Paleogene convergent margin: (1) deformed (para)autochthonous NOAM Jurassic and Cretaceous continental margin and basin sections and Paleocene-Eocene synorogenic foredeep deposits; (2) oceanic lithosphere and associated sedimentary rocks that formed on CARIB, including ophiolite complexes and serpentinite mélanges. These oceanic crustal assemblages are associated with ca. 135–47 Ma magmatic activity and interbedded with or overlain by synorogenic basins; and (3) (neo)autochthonous late Eocene to Recent deposits that unconformably overlie the two older units (Figs. 1B and 2; Iturralde-Vinent, 2011). Many of these units were partially subducted, metamorphosed, and exhumed. These lithotectonic associations are briefly summarized in the following sections.”
        https://www.geosociety.org/gsatoday/archive/26/10/article/i1052-5173-26-10-4.htm

        88 million years of magmatic activity, all assembled on the Caribbean ocean floor. Plus subduction. Big library for submarine science.

    • Back now.
      There is lava at the north flank, where there cannot be without the effusive vent.

    • That foreground effusive vent is looking a lot more ashy today, seems to me.

  23. Unlike our late Icelandic friend I can’t recall seeing any wet weather on La Palma. I guess it will make the ash clog harder .

  24. La Palma time arround 09:15 Ocean Entry? Steam or smoke the near the surface of the water.
    (Feed #3)

    • Notice the lack of pillow lava. I guess that pahoehoe would be needed for that.

  27. ….and we’re back to Etna. A big ashy explosion this morning

  28. La palma. On the last hours, multiple lava flows to north and wes has open on volcano flank, some explosions.

  30. Wondering about the height of Tajogaite now. Officially it is confirmed at 200 meters tall, presumably that is meaning 200 meters above the ground the vents first opened on, so it is actually taller facing the live camera perhaps even closer to 300 meters that way.

    Pu’u O’o failed when it was about 250 meters tall, with the eruption going downrift. Etnas summit cones have frequently done this too, only they seem to be more resilient and will fix themselves afterwards in a repeating cycle. I cant help but wonder if a low altitude effusive vent is going to open on La Palma, probably close to the current cones but then again in some older eruptions the effusive vents were some distance from the main one. The lava is very fluid now and it looks like sometimes there is a bit of a lava pond in the crater, at least in the one feeding the lava flows. We have already seen now weak the cone can be, a lower vent is not at all outside possibility especially if the cone keeps gettign bigger as it seems to be. If a low altitude vent opens it will probably be entirely effusive with little or no fountaining so will not turn to a’a as fast, it will be a lot more dangerous if it goes over new areas.

  31. The KT boundary is fascinating…
    As example: did modern megathermal broadleaf tropical rainforests exist during the Latest Maastrichtian? 66 MA. Did the dinosaurs walk through hardwood broadleaf rainforests during the very end of their reign? And When did these angiosperm rainforests evolve?

    Hell Creek Formation 66 Ma is dominated by angiosperms and was a tropical seasonal moonsoon forest with only minior gymnosperm elements. Walking With Dinosaurs last episode potraited Hell Creek very wrong in the forests enviroment, better they shot it in Indias moonsoon forests than in Chile. The dinosaurs where also outdated now in that episode.

    Modern Megathermal broadleaf tropical rainforests haves a very poor fossil record, because decomposition is extremely rapid in the heat and humidity. Only a few oxygen poor localities in the world have preserved them.
    The fossil record of modern Jungles been poor and mysterious.

    But example as PETM 50 million years ago, we know that already 50 million years ago that the entire planet was covered by modern megathermal rainforest, fossils from oxygen poor anoxic lakes like Messel Pit, London Clay, Bighorn Basin and Green River formations as well as European Amber, and some seafloor pollen cores.

    Messel Pit 49 Ma is the most detailed and most extraodinary fossils that have ever been found, color, fur, cells, even eyes turned to stone. That locality had made it clear, that it was very similar to Borneo today in species of plants and animals back then. Pretty much all modern megathermal rainforest plant and animal elements have been found in Messel Pit.

    Titanoboas carbon deposits in South America from Paleocene 60 million years ago, have shown a very similar biota to todays rainforests. Just with extinct giant snakes, crocs and turtles. Very similar to today in the huge angiosperm diversity, just perhaps a little less diversity in the diversity of plant species.

    Primate evolution seems co – evolve with the rise of angiosperms and fruit, most species never fossilize. Looking at the genetic molecular clock of primates, puts the origin back to almost 80 million years, long before the Late Paleocene early primate fossils. And 80 million years ago is also during the Cretaceous Terestrial Revolution I think. That perhaps puts the origin of the modern tropical rainforest to 80 million years ago?

    • Chad Whats your opinion?

      Any modern megathermal rainforest in the Meozoic?

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