The Orinoco Flow: sediment subduction and the Lesser Antilles volcanic arc

Radiogenic isotopes and the origin of volcanic island arcs

Isotopes are amazing geochemical tools. They can be used not only to date minerals radiometrically but to constrain small and large-scale geological processes. The subduction of oceanic sediments into the mantle is one such process, about which geologists want to know: what is the ultimate fate of ocean-bottom sediments? For example, what portion of these sediments is taken down into the mantle? How much is scraped off onto the accretionary prism? And finally, what portion of oceanic sediments are melted and returned to the surface through volcanism?

Some of the most important isotopic ratios used to answer these questions are also used in radiometric dating: 87Sr/86Sr, 143Nd/144Nd, 206Pb/204Pb, 207Pb/204Pb, 208Pb/204Pb, 176Hf/177Hf, and even 10Be/9Be. In each of these ratios, one isotope is radiogenic (produced by radioactive decay) and the other is stable. This ratio changes over time, therefore, based on the concentration of the radioactive parent element (Fig. 1). Since the isotope 87Rb decays into 87Sr, for example, the 87Sr/86Sr ratio will increase at a faster rate in minerals with a higher concentration of Rubidium than in minerals with zero Rubidium (i.e. if no Rb is present, the 87Sr/86Sr ratio will never change).

Figure 1: Isotopic evolution of 87Sr/86Sr over time in various Earth reservoirs.

The application of this principle to geochronology is straightforward: if the original isotopic ratio and decay rate can be determined, then so can the age of the mineral. But what does this have to do with plate tectonics, subduction zones, and island arcs in particular?

Consider the Lesser Antilles volcanic arc—that parabola of paradise off the north coast of Venezuela. These islands have been forming through volcanic eruptions over the past tens of millions of years, as Cretaceous-aged basalts and sediments were subducted beneath the Caribbean tectonic plate (Fig. 2). A portion of these rocks/sediments then began to melt upon reaching a depth of ~100 km, causing magma to ascend toward the surface and mix with the upper mantle (check out a visual explanation here). Since the subducted crust/sediment and the upper mantle are of different age and composition, their isotopic ratios will also be distinct (remember how and why these isotopic ratios change?). The final product (surface volcanic rocks) depends of the relative contribution of each, much like mixing yellow and blue paint in varying quantities to produce different hues of green. This geochemical variation is the key to answering the aforementioned questions for each volcanic arc around the world.

Figure 2: Age of basaltic oceanic crust (K-Ar method) currently being subducted beneath the Lesser Antilles island arc. Note that radiometric dates increase systematically from north to south, as expected from the geometry of the crust (distance from the spreading center) and the current plate movement of ~2 cm/yr. In other words, rocks that are 400 km further from the spreading center (the star marked 'Barbados' vs. the northernmost age) are about 20 million years older (~400 km divided by 2 cm/yr is 20 Ma; 105 Ma - 83 Ma = 22 Ma). From Carpentier et al. (2008).

From mantle to crust

Now take a step back in time, to an ancient Earth where massive continents do not yet exist. Much of the Earth's upper mantle would have had a very similar isotopic composition for elements such as Sr, Nd, U, and Pb. As early as ~4.3 billion years ago, basaltic crust began to crystallize at the surface. In the 'short' interval between ~3.5 and 2.5 billion years ago, a majority of continental crust also formed, and the mantle and crust became geochemically isolated reservoirs. Since the process of crystallization always prefers certain elements over others (smaller elements over bigger ones), each reservoir developed unique relative abundances of parent/daughter pairs. For example, the relative abundance of Rb vs. Sr is higher in the crust than in the mantle, so the isotopic ratio 87Sr/86Sr increases faster over time in crustal rocks than in the mantle. On the other hand, Sm vs. Nd is higher in the mantle than in the crust, and so the isotopic ratio 143Nd/144Nd increases faster in the mantle than in crustal rocks. Since 238U decays to 206Pb, relatively high abundances of Uranium (as in crustal rocks) contribute to higher 206Pb/204Pb ratios in continental crust.

In short, high 87Sr/86Sr and 206Pb/204Pb ratios accompanied by low 143Nd/144Nd ratios are good geochemical signatures of very old continental crust. Unless, of course, one can propose a viable alternative mechanism to explain their origin and evolution.

Sediment contribution over time to the Lesser Antilles archipelago

In the following graphics, one can see how geologists apply these isotopic systems to understand the contribution of subducted sediment to volcanic eruptions. First, we need to determine the 'hue' of our yellow and blue paints (i.e. the mixing 'end-members'). On the one hand, we have upper mantle that resides directly beneath the volcanic islands. The isotopic composition of the upper mantle is relatively easy to determine, since it is continually sampled and preserved by Mid-Ocean Ridges (MORs). Dredging ships frequently collect samples of Mid-Ocean Ridge Basalt (MORB), which are then analyzed for their isotopic and elemental compositions, as well as their magnetic polarity and age. Not surprisingly, MORBs from around the world are geochemically very similar. Furthermore, their distinct geochemistry is consistent with theories that the chemistry of the upper mantle is due to the formation of oceanic crust early on in Earth history (see previous section).

Our second mixing end-member is formed by clay-sized particles that sink to the bottom of the ocean. The origin of these particles is found on continents, where old continental crust is weathered and carried out to sea by major rivers. Fortunately, the ocean sediments being subducted beneath the Lesser Antilles have also been sampled in many places by the Deep Sea Drilling Project (the stars in Figures 2 and 3 represent such sites) and analyzed geochemically.

To determine the extent of mixing between these end-members, volcanic rocks are sampled along the arc. Figure 3 is taken from one study that focused on the petrologically diverse island of Martinique, which developed in multiple stages of a long eruption history. Since the volcanic island formed over the past 25 million years, the authors were able to address this question for much of the Cenozoic.

Figure 3: From Labanieh et al. (2010). Map of the Lesser Antilles volcanic arc and Martinique island, for which three stages of the island's volcanic history are delineated. Sampling sites of ocean sediments (stars) and volcanic rocks (see inset) are also shown. As an aside, note the width of the accretionary prism (distance between the 'Subduction trace' and the 'Prism front'). How long must this subduction zone have been collecting sediment?

One can predict the composition of the final product by plotting the isotopic compositions of both end-members on a graph with isotopic ratios on each axis (Fig. 4). The more that subducted sediments contributed to magma generation in the subduction zone, the closer those values will plot to modern isotopic ratios of oceanic sediments (dark gray fields):

Figure 4: From Labanieh et al. (2010). Four isotopic cross plots from Martinique Island,  indicating a significant contribution of oceanic sediments during magma generation (up to 20%). Red/Blue lines are mixing lines between MORB values and ocean sediment values. The range of compositions of Mid-Ocean Ridge Basalts between 30°N and 30°S are shown in light gray fields.

It is evident from the examples above that the composition of volcanic rocks on Martinique Island are due to a mixture between the upper mantle and subducted oceanic sediments. One can also see how the extent of mixing is variable in time and space (Fig. 5). For example, note how the mixing lines—blue vs. red—shifted slightly when the arc itself moved west (cf. Fig. 2). This westward shift in volcanism was possibly due to a shallowing of the angle of subduction following the subduction of an aseismic ridge around 6–7 Ma (Labanieh et al., 2010). In any case, the isotopic mixing trends seen at Martinique Island are common to the rest of the islands of the Lesser Antilles and are prime examples of this phenomenon of plate tectonics. These data also corroborate the theory elegantly, since they are predicted directly by it.

Figure 5: From Labanieh et al. (2010). Relative contribution of oceanic sediments over time, based on K-Ar dating of individual volcanic rock samples. After 5.1 Ma, the end-member composition changed, possibly due to the subduction of an aseismic ridge on the Atlantic Plate.

The Orinoco Flow

Figure 6: From White et al. (1985). Isotopic con-
tours show more radiogenic Sr and Pb in front of
the Orinoco River delta. Results are similar when
Nd isotopes are plotted.

What is the source of deep-ocean sediments being subducted between the Caribbean tectonic plate? One key to answering this question is the geographic variation in isotopes along the Lesser Antilles arc. Nearly 30 years ago, White et al. (1985) documented the modern influence of the Orinoco River on the isotopic composition of sediments lying immediately in front of the Caribbean Plate (Fig. 6). Since the Orinoco River watershed drains sediments derived from very old continental crust (the Archean-aged Guiana Highland), 206Pb/204Pb and 87Sr/86Sr ratios become higher as one moves closer to the river delta. We can predict, therefore, that these isotopic ratios are higher in volcanic rocks from the Southern Islands than in those from the Northern Islands.

As it turns out, that is precisely what White et al. (1985) and later researchers found. Although the debate regarding the significance of this mechanism is not yet fully settled (Carpentier et al., 2008), it is generally agreed that the Orinoco River basin has long been in place (since the Cretaceous) and contributed sediments enriched in radiogenic isotopes to the subducting slab.

Figure 7 represents a cross-plot of Nd and Pb isotopic data from the island arc. As you may recall, the relatively high 206Pb/204Pb and low 143Nd/144Nd ratios are characteristic of old continental crust. Such values (note the Site 543 sediments field) are represented more by the Southern Islands than the Northern Islands. This trend suggests that the geochemistry of volcanic rocks along the Lesser Antilles arc is strongly determined by the geochemistry of oceanic sediments in front of the arc.

Figure 7: From Carpentier et al. (2008). Cross plot of Nd and Pb isotopes showing greater contribution of oceanic sediments in the Southern Islands than in the Northern Islands.

To add some icing to our petrological cake, Carpentier et al. (2008) also demonstrated that Uranium-rich black shale units, which were deposited during the Late Cretaceous Oceanic Anoxic Events (OAE I and II), could account for anomalously high 206Pb/204Pb in the Southern Islands, since they are present only in sedimentary strata to the south. Over time, 238U decays to 206Pb, so the ratio of 206Pb/204Pb will increase at a faster rate in U-enriched sediments relative to the crust or mantle. What does all this mean? Even the islands of the eastern Caribbean can attest that the oceanographic events responsible for these black shales (a long-term reduction in available oxygen to the oceans) occurred more than 80-million years ago, while the Atlantic plate was being subducted slowly (about 2 cm/yr) below the Caribbean plate.

Conclusions and implications for YEC

Corroborative evidence is still being discovered for Plate Tectonic theory, which revolutionized geological disciplines in the 1970's. The Lesser Antilles volcanic island arc is a prime example of the phenomena associated with the subduction of oceanic crust and sediments. Combined isotopic data from numerous elements demonstrate how conventional theories regarding the Earth's age and history can be tested through multiple, independent methods. Simultaneously, one can see how such theories are potentially falsifiable, since they were formulated before the isotopic data were available, yet were able to predict trends in those data. If you were able to follow the examples above, I hope you will better understand how geology has progressed scientifically (rather than through conspiracy and ideology).

Young-Earth Creationism has attempted to keep up with modern geology by transforming Plate Tectonic theory (which describes a notably slow process) into 'Catastrophic' Plate Tectonics—a process that barely works on paper, but so rapidly that it would have boiled off most of the oceans. The latter is hotly debated within YEC and not accepted by many. Personally, I would predict its disappearance in the near future if it weren't so necessary to accepting the obvious evidence for Plate Tectonic theory. It will be interesting to see whether YECs make any attempt to adapt to the flood of new evidence for the theory's more conventional version.

Despite the fact that Catastrophic Plate Tectonics is an abstract, geophysical model (i.e. difficult to grasp or critique by the layman—myself included), one can ask whether it accurately predicts the relevant evidence. For example, how does Catastrophic Plate Tectonics explain the isotopic data presented above from the Lesser Antilles? How did the South American continent crystallize from molten rock (a slow process in itself), decay radioactively to produce distinct Nd, Sr, and Pb isotopic values (a 2.5 billion-year process), deform structurally (to form major river basins like the Orinoco), weather extensively (to fill the North Atlantic basin with fine-grained sediment, which typically needs thousands of years to settle at the ocean bottom), and yet be covered with miles of Phanerozoic sediments? When the big picture is considered as a whole, the YEC mentality becomes a fleeting illusion.

Radiogenic isotope data from the Lesser Antilles arc seem to indicate that oceanic sediments have long been weathering out of the Orinoco River watershed, subducted beneath the Caribbean Plate, and melted and incorporated into the magma that produced the idyllic islands of the eastern Caribbean. Radiometric dating of volcanic rocks and oceanic crust corroborate the picture interpreted from radiogenic isotope data (Fig. 2), and are even predicted by modern rates of subduction and distance from the trench to the spreading center. The Beryllium-10 method (which I will discuss in a later post) provides an additional test to determine that the process of subduction occurred over several million years rather than several hundred.

Catastrophic Plate Tectonics and YEC cannot account for the isotope trends in volcanic arcs, because they provide no mechanism by which distinct isotopic signatures form in a matter of hundreds or thousands of years. Furthermore, these paradigms cannot explain the origin of massive amounts of continentally derived sediment, which were subducted beneath oceanic plates before the modern tectonic picture formed (i.e. before the Flood). I will return to this point in the next post when I discuss Dr. Andrew Snelling's article entitled "The Relevance of Rb-Sr, Sm-Nd, and Pb-Pb Isotope Systematics to Elucidation of the Genesis and History of Recent Andesite Flows at Mt. Ngauruhoe, New Zealand, and the Implications for Radioisotopic Dating", in which he cunningly misrepresents the geochemical methods employed to understanding volcanic arc systems.

If this post was sensible to you, his errors will be obvious.


References Cited:


Carpentier, M., Chauvel, C., and Mattielli, N., 2008, Pb–Nd isotopic constraints on sedimentary input into the Lesser Antilles arc system: Earth and Planetary Science Letters, v. 272, p. 199–211.

Labanieh, S., Chauvel, C., Germa, A., Quidelleur, X., and Lewin, E., 2010, Isotopic hyperbolas constrain sources and processes under the Lesser Antilles arc: Earth and Planetary Science Letters, v. 298, p. 35–46.

White, W.M., Dupre, B., and Vidal, P., 1985, Isotope and trace element geochemistry of sediments from the Demerara Plain region, Atlantic Ocean: Geochimica et Cosmochimica Acta, v. 49, p. 1875-1886.

"Orthodox at Heart"—a personal reflection on the church in Russia

Such is the title of my guest post over at The Two Cities blog. If you're interested in the topic, please check it out and feel free to comment on the article at either site.

Much could be said in comparison of American and Russian churches. One topic at which I only hinted (but didn't have room to explore), is that of the relationship between the church and our respective  political revolutions (in 1775 and 1917). Both revolted against monarchist states, accused of exploiting the wealth and prosperity of the people while infringing on individual rights. Both led to quasi-secular nations that broke with the European tradition of a state church. In the American case, however, religious freedom was emphasized as a divine right, and the replacement oligarchy touted a quasi-Christian deism, in which God could be found through academia (forgive the oversimplification). For Russia, religious freedom was promoted only to undermine the Orthodox Church (associated with the strength of the Imperial upper classes), but later squashed through censorship and persecution. As a result, continued health of the Soviet Union relied on a new standard of orthodoxy, and to stray from such made one an enemy of the State. Despite the ostensible opposition to liberty, this structure secured the government against future revolution, as was seen, for example, in the American Civil War (for Southern Independence) scarcely 85 years after the nation's founding.


As the commemoration of our American Revolution approaches, we might ask ours uniquely bears on modern affairs, mindsets, and particularly the church, compared to those of other countries. Many Russians ask today whether their own revolution marked a positive or justified turn in national history. If we ask the same in America, what kind of answers emerge?


I never thought to ask this question, so I thought I would share.

This is St. Petersburg

Never do things turn out as you expect; I should have expected nothing less in moving to Russia.

It has been a month since we landed at Pulkovo airport, but only today did I feel that I actually 'live' here. Despite my hope that my summer would abound with free time to read and write, each day has flown by with a series of small tasks, whose size alone could not predict the induced stress and required time to complete. Yesterday, we visited a friend that was holding part of our luggage while we searched for an apartment. I timed the 9-mile journey: 8 minutes walking to the bus stop; 13 minutes riding to the Metro station after waiting nearly five. We spent another 39 minutes total in the subway (three lines, two transfers), after which we walked 8 minutes to another bus stop and waited 4 minutes for the right bus, which drove 8 minutes to our stop. Only 10 minutes of walking remained (that's 95 minutes total) before we took an elevator to the ninth floor and called victoriously through the door: "Мы пришли!"

"The Crimson Drawing Room", Yusupovskiy Palace

I miss my car and my freeways, but really we shouldn't complain. In exchange, I am living in the heart of a world-famous city that is ripe with history and cultural opportunity.

So perhaps I should begin with the good news? After more than two weeks of searching, we found a comfortable, clean apartment on one of the most famous streets in all of Russia: the Moika river embankment (Набережная реки Мойки). Alexander Pushkin once lived on the same, along with countless Russian nobles during the imperial age. Our apartment building—built in 1862 by a noble family for naval officers—faces the river, on which boats full of tourists or unwinding locals continually pass. Only a 5-minute walk takes us to St. Nicholas Naval Cathedral (Никольский Собор), the Neva River (see below), or the famous Yusupov Palace (Юсуповский Дворец; worth a Google-image search), in which Rasputin was assassinated shortly before the family was forced to flee Russia by rising revolution.

About 1:30 AM, the bridges of the Neva open for oversized traffic.

It was not without trial, however, that we recaptured what I came to know as a 'romanticized' view of the city. During my visit in December, we did not venture far outside of the 'Noble' city center. Upon our arrival, we soon learned that the most of St. Petersburg is not unlike any other Russian city: endless blocks are filled with familiar Soviet infrastructure and architecture; public trash cans overflow onto the streets and parks; cigarette smoke bellows from sad faces with a beer in one hand and a baby stroller in the other; excessive graffiti marks otherwise historical monuments, to which rusty metal doors offer little invitation; constant traffic inspires every driver to act as though he/she is transporting a woman in labor on a reality TV show. More importantly, however, we now had to deal with a range of services (from real estate markets to mobile phone providers to educational institutions) not used by tourists, as well as the peculiarities produced by a free market catered to Russian demands (of which common courtesy is not one!).

To be fair, we Americans share many of these habits and attitudes toward ourselves and our own cities, which are far from spotless. I think we just tend to 'hide' them better with countless misdemeanor laws. Though these laws exist in Russia, the police have no interest in enforcing them and the fines are so minimal (about $3 for speeding ~10 km/hr over the limit) so as to be ineffective. And though we take pride in our smiling faces behind the counter, a sincere care for strangers is notably rare.

Russian Real Estate

This common wooden flooring is creaky and
hygienically suspect, but quite durable!

Our greatest challenge by far was finding a permanent residency. After staying a weekend with friends, we managed to find a temporary 2-room apartment for rent. Although the conditions of the 80-year-old apartment were somewhat shocking at first, by the end of our weeklong stay (half the price of a hotel) we were very surprisingly comfortable and desired not to leave. This apartment was located downtown, one-block from Nevsky Prospect and Moscow Train station (i.e. the station from which trains depart toward Moscow), which made it a convenient, central point from which to explore the city. We did not anticipate, however, the complexities of the local real estate market. In fact, I would like to suggest to any entrepreneurs that one could turn a significant profit by streamlining this process.

If you want to find an apartment in the U.S., the process is rather straightforward and simple, especially if you have a neighborhood in mind. With internet access, you can basically 'walk' your prospective streets on Google maps until you find a nice looking complex, or sift through pages of website databases that sort by price, amenities, etc. In either case, you need only call the office to inquire about details or check out their website to find numerous pictures of each model. If you're in the area during business hours, you can even drop in for an immediate showing of available units. Rinse and repeat until you are satisfied with your new residence.

A very typical Russian kitchen: small, with
small appliances (including the washing
machine!) and minimal counter space.

Let's take a step back 80 years, and forward twelve time zones.

During the Soviet era, every piece of property was nationalized. Your residence was essentially assigned to you, and tenants had no liberty to move around or upgrade to different units (though a waiting list was available). On the one hand, you could enjoy life without the anxiety of mortgage payments and potential loan defaults. In exchange, however, three-generation families typically lived in a cozy, but incredibly tight space (300–600 square feet). Showers were nonexistent and bathtubs were a luxury. Many buildings were not even designed to carry them, as bathing was reserved for a weekly trip to the communal bathhouse (banya). The familiar 'blocky' Brezhnevka units, produced in mass during the late 60's, were notably cold from the concrete walls/floors and visually unappealing, but they were a significant step up for those living in 'Kommunalki', or Communal Apartments.

Everything changed with the post-Soviet 'reconstruction' era, when all property was instantly privatized. This meant that each family inherited the apartment(s) in which they lived. No mortgage, no rent; it was yours. Moreover, any family fortunate enough to have turned a profit in the free, but fierce, market could finally purchase something newer, bigger, and better. Enter the modern Russian real-estate market.

Somewhat reminiscent of my own childhood,
metal swings and teeter-totters fill the yards.

Although newly constructed apartment buildings appeared very slowly in the 1990's, vacancies abounded as millions of Russians fled through recently opened borders. Even today, many landlords of Russian apartments live abroad and rent out by giving power of attorney to friends/family (keep this concept in mind). The owners of our temporary home, for example, live in Germany and typically rent the place to international students at ~50% above market price. As an aside, most landlords prefer to deal only in cash, for it allows them to hide their supplemental income from being taxed. Since ~100% of your rent payment is income for the landlord, and the average rent and average salary are approximately equal, it pays well to be a landlord in Russia.

So what does all this mean for the potential letter of a Russian apartment? First, there is no such thing as a commercial 'apartment complex' with a manager's office, website, model units, and the like. Each individual unit is privately owned. Consequently, you can find vacancies only by word of mouth, internet databases, or real estate agencies. Second, the demand for apartments in major cities is extremely high, so you can hardly afford to be picky. Unless you work in the oil industry, your best economic opportunities are in St. Petersburg, Moscow, and the Volga cities. Russia is second only to the U.S. in terms of immigration, moreover, so thousands of new workers flood these cities each year, hoping for a chance to send money back home (in fact, the political parallels in immigration debates between the U.S./Mexico and Russia/former Soviet Republics are striking, right down to the cultural stereotypes). Lastly, where there is money, there is fraud and corruption. Renting an apartment from a crook is a common way to lose your savings.

The Search

Since real estate agents understand the market demands, they do very little work for too much money. In major cities, you can expect to pay 100% of the monthly rent as a "finder's fee" to the agent, and unless you are well connected or extremely patient, agents are necessary to your search. Very few are courteous/helpful, and many will not even take the trouble to e-mail you photos. Online databases are a tempting place to start, but once you call the number on the ad, you are likely to hear the following:

"Hello, I am calling about ad online for the apartment on Soviet street." "Sorry, it has been rented out. What are you looking for?" "We need a place with x, y, and z, no more than such and such price, near this metro station." "And who will be renting?" "We are a young couple, husband and wife, no kids or pets." "Both Russian?" "No, one is American." "White or black?" "White." "Good. Let me search and I will call you back."

We found that many ads are left posted because they draw a lot of calls, despite the fact that the unit is unavailable. Also, if you are single, or have kids, pets, or a face that doesn't look Russian or 'western European', your choices will be limited. At this point, the agent will search the common database (a highly specialized task, I know) and call back several hours later with some options:

"Hello, I found four apartments! Here are the addresses and specifications. Would you like to see any of them?" "Yes, the third one sounds nice." "Okay, I will call you back with an appointment time."

Now the agent will call another agent, who will call the apartment owner about a showing time, since the agents themselves do not have access to each apartment. Once the owner returns the call, the other agent returns his/her call, and you will hear back from the first agent within...1–2 days. You may have figured out by this point that working with multiple agents simultaneously can speed up the process.

Now it's time to see the apartment. Making your way across town can take up to an hour or more, so be sure you have no other priorities in life. Keep in mind also that 90% of apartments here are barely livable by modern standards, so you must give each the benefit of the doubt. Nonetheless, on three occasions we didn't even make it to the building before deciding 'absolutely not'. On three other occasions, even the realtor was shocked at the condition of the apartment. In two cases, the kitchen was in the hallway; once the bathroom was in the kitchen (I couldn't make that up). Sometimes the elevator worked, but just barely, and life's too precious to trust equipment with that much rust. Other times, the elevator was turned off to preserve power, or there was no elevator at all. Sometimes the real estate agents would smoke and talk on their phone while showing you the apartment. Often the address you were given was not the actual address, so the online street view would become a shattered dream. And as a last reminder, '10-minute walk from the Metro station' seems to be code for 'a 20-minute jog'.

To complicate matters (though for our own benefit), we received some friendly advice on how not to get scammed. Consider the following for future reference:

1. Never sign a lease with anyone but the owner of the apartment. Even if the unit is rented via Power of Attorney, the owner can arbitrarily vacate the premise ("Sorry, my family wants to visit St. Petersburg, so you'll have to move out now"). Demand to see the papers proving ownership before signing the agreement.

2. That being said, do not deal with realtors alone. The agents are nothing but middlemen, who profit by hiding information from you and from the owner. They make no guarantees and their fees are non-refundable.

3. Try out everything—stove, fridge, faucets (both cold and hot), bed, bath, shower, and toilet. Even do some business and make sure it flushes. Apartments are not likely to come with free maintenance.

4. Take pictures of all original documents. If you can, take pictures of the realtors themselves. It is not uncommon for crooks to rent an apartment temporarily using a forged passport, and then impersonate a real estate agent with a forged Power of Attorney to rent it to you, the hopeful tenant. If they are successful, they will make off with the agent fee, first month's rent, and a security deposit (~$2–3,000 total), while you are stuck with a set of keys that don't even fit the lock.

Next stop, St. Isaac's Cathedral—an architect-
ural masterpiece and cultural icon. View from
our street.

5. That being said, sign the lease and pay the fees inside the apartment with owner and realtors present. If everything works in your favor, you will never see the agents again; make sure you have no reason to. On the other hand, you will deal with the owner regularly. It is good to leave an endearing impression.

6. Lastly, don't be afraid to bargain and pretend that you are poor. Although market demand is high, and the odds are not in your favor, every case is different—you might get lucky! In our case, the owner was willing to replace the stove and sink, install a dishwasher, and redo the main plumbing at no cost, just to make it comfortable and presentable to her American tenant. We were very blessed.

At last, a place to call home

We did not expect to find a reasonably priced residence in the heart of the city, but rarely do things turn out as you expect. We faced none of the worries implied by the points of advice above and were rather shocked by the grace and kindness of our landlord. By the kind providence of God, we have come to experience that romantic perception and may live comfortably in what once was Peter's noble bastion, what became Leningrad—the city of heroes—and what is now a piece of living history. The neighborhood is both beautiful and friendly; numerous grocers, restaurants, and bus stops are within short walking distance. On that note, if any of you find the opportunity to visit St. Petersburg, do not hesitate to contact me. We'd be happy to show you around the city.

White Nights

View looking north in mid-June, ~2 AM.

In St. Petersburg, part of the summer is devoted to celebrating "White Nights" with nightly fireworks, concerts, and heavy pedestrian traffic past midnight. At 59.5° N latitude, the summer nights scarcely end. Jet lag is a challenge wherever you go, but here it was complicated by the lack of regular darkness. After the first week, we had adjusted to the Russian time zone; after two weeks, we nearly adjusted forward to PST. It is difficult to convince oneself that it is time to sleep when the sun never sets completely. On a clear night at 2 AM, it appears to be sunset, until you realize that the sun is 'setting' in the north—not the west. At 4 AM, it is fully bright again. Nonetheless, we enjoyed many late-night walks along the riverbanks of the Neva and Moika. It is a brilliant contrast to the cold, dark winter we had previously experienced.

What's next?

Now that we are settled in, my goals are simple: take advantage of the university to learn Russian more fluently; complete field work on several geological projects; write some posts about the latest in YEC news; eat lots of soup, pelmeni, pirogi, and chocolate; drink lots of tea, but only a little vodka; enjoy the city, especially its museums; and of course, stay healthy and have fun. The tea/chocolate are perhaps the most pertinent.

I hope this personalized detour has kept your interest. I will end here with some photos that didn't make it into the main text. See you next time.

St. Petersburg–Helsinki–Tallinn–Stockholm–Copenhagen;
sail the Baltic at a reasonable price! The port is a 5-minute walk
from us. (Photo taken from the bridge in the video above.)

Artificial zoom on the iPhone: just good enough to capture the midnight
skyline along the Neva.

Sleepy? Marry a Yusupov.

Arched entrance to "New Holland" island, built in Peter I's
time to house lumber for the shipyards and naval prisoners.
View looking across the Moika river from our street.

Looking west down the Moika; New Holland Island on the right.

I've always wanted a circular love seat under a hemispheric ceiling...

The concert hall and dance floor became deceptively large with the raised ceiling and its fleeting geometry, as well as  mirrors on both walls. Keep that in mind when designing your next home.

Did Alexander Pushkin leave a personalized copy of Homer's Iliad on your bookshelf, too? Strangely, I had an easier time reading the Greek on this page than the Russian translation...

This art gallery (i.e. the hallway connecting the concert hall to the theater) was once filled with a private collection that rivaled most in Europe. Note the skylight and brightly toned walls to illuminate the canvas paintings.

This hallway connects to the prior...

And leads here: another art gallery, which connects to the theater. The door on top is for the family 'box seats', while the stairs lead down to the guest seating (including those for the Emperor).

"Because it's my house, and I want to be noticed when I invite world-class musicians and thespians to entertain me and my guests." This has to be one of the most beautiful theaters around. Fortunately, the Russian educational ministry has kept it open for the occasional play/concert.

The stage is apparently as large as the theater itself, though it is hidden by curtains. Also hidden is the orchestra pit with seating for twelve musicians (look for the gap before the stage).

St. Nicholas Naval Cathedral. We happened to pass it on one of our walks downtown (of course, it's hard to miss).

This inspirational monument watches over Palace Square (see below).

Hermitage Museum (former Winter Palace of the Emperor). View from Palace Square.

I saw the masts from our apartment window and had to take a look. Can I steer?

View of the Izhora Plateau from Dudergof—one of several hills that breaks the flat landscape. During WWII, the city of Leningrad was under siege for 2 1/2 years. Hitler fully expected to capture it swiftly, rename it Adolfsburg, and then move forward to take Moscow. Instead, he was met with fierce resistance by a starving population. The campaign inflicted more than 1.5 million deaths—many of whom were civilians—but ultimately failed, nonetheless making it the most deadly in history. Essential to the siege was constant bombing from artillery, which gained a vantage point from this and other hills.

Speaking of German artillery...

View from the adjacent hill.

Ordovician carbonate strata underly much of the landscape (part of a field trip with the Physical Geography class at the university).

Something serene about the Russian summer cottage... Photo taken on the Izhora Plateau.

Strawmen, Sunday School, and St. Petersburg

St. Petersburg
Last things first. I thought it might be fitting to update everyone on my plans for the coming year. Recently, I received news that I have been awarded a Fulbright Scholarship to conduct research in St. Petersburg, Russia. Though the grant period begins in September, I will be moving to the Russian metropolis in less than two weeks to get an early start on my work (not to mention a change in scenery!). The news could not have come at a better time, as I was about to give up hope on deciphering Russian immigration policy and procedure (even being married to a Russian citizen, I would have numerous legal hurdles).

So a stipend and visa sponsorship have significantly simplified our lives, and we are grateful for the opportunity. Simultaneously moving further from and closer to friends and family, we will find ourselves in good company while cherishing connections strained. More pertinent to you, however, I anticipate having more personal time (not to mention, space to think and breathe), and I intend to fill part of that time writing more frequently here. My only question is: do I need to refocus my goals? Is my time better spent responding to the misuse of geology in young-Earth circles or discussing a positive, fresh outlook on scripture/science outside of the rigid confines of YEC hermeneutics?

Sunday School
Perhaps of interest to some of you, I recently finished teaching a 5-week Adult Sunday School course on 'Reading the Primeval History of Genesis'. Overall, feedback from the class (20–30 people) was very positive. It was my first time teaching (in person) on the subject, however, so at times my thoughts were somewhat disorganized and poorly articulated. Above all, I learned what is most important to say when you only have 45 minutes to cover a topic as broad as, for example, Genesis 6–9. On the other hand, preparing lessons for each section revealed how much I have yet to learn, particularly in a comprehensive study that seeks to elaborate all aspects of the text from literary to historical/cultural to theological. I am hesitant to post the audio or link directly to it here, but if you are interested in hearing my approach to Genesis 1–11, please contact me and I will provide those links.

The early chapters of Genesis are by far the most influential on biblical theology as a whole, and New Testament authors from Matthew to Paul to the apocalyptic John often framed their message in terms of Genesis motifs. Therefore, it is no understatement that this small compilation of stories from ancient Israel has shaped the course of world history out of proportion to her political fame in the Ancient Near East. In other words, it was not the stories of Egypt, Assyria, or Babylon—all of whom succeeded militarily at one point against Israel—that captivated the human heart and inspired millions to cultivate God's Eden. Why? What stood out in Israel's story that brought life to the land and its inhabitants?

In the first lesson, I attempted to fracture our modern hermeneutical lenses, which prevent us from reading scripture outside of our own time and place. Genesis was not written, for example, to lay the groundwork for modern scientific paradigms. Attempts to synthesize Genesis with modern science grossly miss the point and prevent us from hearing the main message. Neither was Genesis written simply to tell people 'what happened' or to provide a more accurate description of events. The story of divine intervention among a catastrophic flood, for example, was the most widely copied narrative in the Ancient Near East, preserved in four literary traditions that predate the composition of Genesis as we know it. Israel was not concerned to get all the historical facts 'right', as is the focus of modern historiography. Rather, she needed to hear why this happened and how these events relate to Israel's story—namely the holiness and mercy of Israel's god. Therefore, the story of Noah and his ark are cast poetically and intratextually in terms of uncreation/recreation motifs, with strong textual and thematic links to the stories of Abraham (Sodom/Gomorrah) and Israel (Exodus/Conquest). My conclusion is that we ought to treat Genesis 1–11 not merely as the 'Primeval History'—a record of original events—but as the 'Prologue to History', which defines the very nature of history itself and prepares us to understand Abraham's position in the cosmos.

In my treatment of the text of Genesis 1–11, I worked within two structural frameworks that I have found most helpful. The first recognizes Genesis 1–5 and 6–11 and parallel units, which elucidate the nature of mankind (i.e. the human condition) and of God's purpose to create a humanity in his own image despite the frailty and wickedness of man's heart:

Genesis 1–5 speaks of God's creation of the cosmos and of humanity, after which mankind is placed in a garden but takes of the fruit of the ground, exposing his nakedness and shame. This story is followed by a conflict between brothers (Cain/Abel), a genealogy that details the origins of culture (sons of Lamech), a prideful humanity (Lamech), and a genealogy that traces God's promised seed (Seth to Noah), through which he would bring mankind back into the garden (Gen. 5:28).

Genesis 6–11 speaks of God's uncreation and creation of the cosmos and of humanity (through the Flood and Noah's family), after which this new humanity works in a vineyard but takes of the fruit of the ground, exposing his nakedness and shame. This story is followed by a conflict between brothers (Canaan, via his father, and Shem), a genealogy that details the origins of culture (the sons of Noah), a prideful humanity (Babel), and a genealogy that traces God's promised seed (Shem to Abram), through which he would bring mankind back into the garden (notice that Abram heads west from Ur, after mankind was expelled east from the garden).

The second framework is logical and views the subunits of Genesis as literary diptychs—two-panelled story structures that explore a more complex reality than a singular monologue might convey. For example, Genesis 1–2:3 and 2:5–2:25 each tell of God's creative work. Both describe that work in terms of a two-part problem: Gen. 1:2, "that the earth was without form (Heb: tohu) and without inhabitant (Heb: bohu)"; Gen. 2:5, "that it had not rained and there was no man to till the ground". One speaks of the origin of life and goodness; the other of the origin of death and evil. In one, God speaks with unrivaled sovereignty over the cosmos and declares the result to be good. Every part of the world has its perfect function, and none disobey. In the other, God recognizes that the situation is not good and works (this time like a farmer, potter, and surgeon) to reshape the portrait into something more beautiful, much like an artist reworking blotches of paint. In both, blessed communion between mankind and God characterize the conclusion, so that creation affects spirituality and social structure as much as it does physics and physiology. Together, these stories tease out the dynamic relationship between God and his creation, which define the very course of history, and celebrate the fact that God is mighty to move in history to bring about his kingdom and will on earth as in heaven (cf. the petitions of the Lord's prayer in light of the narrative realities in Gen. 1–3).

Genesis 1–11 is comprised of 6 literary diptychs, which comment on creation (Gen. 1:1–2:25), sin (3:1–4:16), multiplication of knowledge and mankind (4:17–5:32), mercy amid judgement (6–9:17), cultural proliferation and the organic unity of mankind (9:18–10:32), and the confusion and curse of culture vs. the unity of culture through divine blessing (11:1–31). The dialogical structure allows the author to explore the basic problems of reality through one of the most unique and sophisticated forms of ancient historiography. The existential and eschatological are intertwined from the beginning, so that all of scripture to follow—whether law, prophet, or wisdom—falls firmly into place.

Strawman Arguments regarding the Nature of Scripture
In the latest issue of the Answers Research Journal, author Callie Joubert argued against the 'incarnational' view of Scripture, which is frequently cited in modern discussions to reconcile the Bible's ancient portrayals of the universe with the notion of divine inspiration (e.g. how can the infallible word of God speak of the sun as rising/setting over a stationary, flat earth?). But her article, entitled Understanding the Nature of Scripture, of Jesus, and the “Dis-Ease” of Theistic Evolutionists (BioLogos), offers little that is qualitatively new to the discussion, in my opinion, and frequently speaks past its interlocutors (senior fellows of Biologos). Consider the opening lines of the abstract:

"To understand the nature of the Bible, theistic evolutionists at BioLogos have proposed that Christians compare Scripture with the divine and human nature of Christ. Underlying this proposal is their assumption that the authors of Scripture and our Lord were not inerrant. The apostle Paul is also singled out as the ultimate source of the “dis-ease” for Christians who are seeking to reconcile the Bible and evolution..." (emphasis added)

Within the Protestant tradition, the incarnational model of Scripture has its conceptual roots in Calvin (not Biologos), who famously warned against learning astronomy from Genesis rather than astronomers. In this sense, Calvin is not far from Augustine, and both are inline with Paul's description in 2 Timothy 3:16, where Scripture is said to be God-breathed. If Paul's intention was to echo the words of Genesis 2:7 (in Greek, the parallel is striking), then the very pages of Scripture may be said to function like the ideal adam: "then the LORD God formed the man of dust from the ground and breathed into his nostrils the breath of life, and the man became a living creature." Like the adam of Genesis 1–2, Scripture is the image of the creator God, and works/lives to extend God's glory across the whole earth through instruction ("have dominion and rule over...") and cultivation ("Be fruitful and multiply... work the ground"). These images of Scripture's role are played out well in the parables of Jesus himself, wherein the gospel message (the word) goes forth to bring fruit, abundance, prosperity and life.

Jesus is the image of the invisible God, being the last adam, and his authority parallels that of Scripture. He is the word of God made flesh, which tabernacled amongst the people. Paul's likening of both Scripture and Messiah to adam proper is thus appropriate, and we should not miss the implications. Jesus—like Scripture—conveyed God's message and glory through human flesh. Jesus spoke in human language, often characterized by chiasm, drama, and metaphor; his words bore the markings of human speech and literature. As Calvin explains, God lisps to us in his speech. Else we cannot comprehend his majestic word.

The paradoxical unity of Jesus' divine and human nature was articulated most famously by the Council of Chalcedon (451 A.D.). Appealing to this doctrine to understand the incarnational aspect of Scripture results in what might appropriately be called a Chalcedonian hermeneutic (follow the link for an original explanation of the term). The basic implication is that we can better understand God's message through the study of history, language, and science. Why? Because Scripture is written in time and space through human language using human conventions, and it appeals to historical social settings and past perceptions of physical realities.

This foundation for reading and applying Scripture is a far cry from that critiqued by Joubert's article. It does not assume "that the authors of Scripture and our Lord were not inerrant". Neither does it, from this assumption, employ creative license to discern where the Bible is right or wrong in light of modern scientific and historical discoveries. Rather, it affirms that God speaks truthfully through human conventions—limited (and even fallible) descriptions of the world and how it works.

In his book I Love Jesus and I Accept Evolution, Dr. Denis Lamoreux (cited in Joubert's article) details this hermeneutic, in which the infallible Message of Faith is contained within the Incidental vessels of human understanding. Both ancient and modern descriptions of planetary motion, for example, are limited and fall short of reality. The Bible is not in error by saying "the sun sets, and hastens around to whence it came," even without our nuancing these words as 'figurative language'. If the biblical author did not intend to make a strict, architectural statement about the world, then the Bible cannot be in error regarding Earth's orbit. His description is phenomenological and true to experience. If we force Scripture to speak where it has not spoken, it is we that are in error.

Joubert thus ascribes a false motivation to Christians that accept science as a valid means to investigate the past. In her first conclusion, she states:

"...theistic evolutionists do their best to convince Christians that the biblical record of creation cannot be trusted as a straightforward historical account because such interpretation is contrary to “science” (by which they mean the evolutionist majority view of origins)."

It is true, the discoveries of modern science have caused readers to reconsider whether and how the language of the Bible corresponds to reality. Joubert and others do not solve this problem, however, by appealing to a 'straightforward' reading. Theologians and literary critics will tell you first that the biblical record of creation is far more dynamic than a literalistic reading allows. The narratives of Genesis are masterfully woven together so as to function canonically throughout Israel's story. Often (especially in the case of Cain/Abel), they are laconic and appeal to the imagination of the reader. One can object to reading Genesis as a 'straightforward historical account', therefore, on scientific and literary grounds.

If we read Genesis 2:7, for example, to imagine that God physically molded and then chemically transformed a 'handful' of dust through his (incarnate?) breath, we have not necessarily misread the text. If we use the text to formulate scientific hypotheses regarding the physical origin of mankind, however, then we have misapplied it. Why? Because the verse functions primarily to establish the true relationship between man and creation and creator, and it does so polemically through well known imagery (the molding of mankind from the earth). This view is confirmed by comparative studies in Ancient Near Eastern literature, and it was recognized even by other biblical authors (e.g. Psalm 103).

Joubert also spends much time writing about Jesus' use of the Old Testament narratives, particularly his reference to Genesis in terms of people and events. She does not establish, however, whether Jesus' exegetical and rabbinic use of these texts necessarily elucidates the authorial meaning. Does Jesus' reference to the creation of mankind as male and female in the beginning depend on Adam/Eve existing close to the beginning of the cosmos (the YEC timeline) rather than much later in history (conventional timelines)? Of course not. Jesus alludes to the text as it stands, and to the narrative reality of Genesis. A modern preacher that accepts the evolutionary timeline could respond exactly as Jesus did to the same effect.

Joubert's flat-footed reading of intrabiblical citations further belies the literary artistry of biblical authors. New Testament citations of Scripture were masterfully creative, sometimes betraying the original meaning intentionally or reorienting original meanings metaleptically around new contexts. To claim that "Jesus applied the text literally, and so should we" neglects the dynamic interaction between Scripture and the Messianic vocation and results in some glaring inconsistencies. How should we live, for example, in response to the fact that the "poor will always be with you" according to Jesus and according to the Torah? How exactly did Jesus "fulfill the Law"? Why does Matthew list exactly 42 generations between Abraham and Jesus (the OT records more than this)?

Christians need to abandon the literalistic hermeneutic of YEC, which provides no breathing space and offers (contrary to Joubert's assertions) no meaningful apologetic. Reading Genesis as 'straightforward history' betrays the intention of the author, whose poetic efforts add depth and richness to theology, if only we are willing to listen. Furthermore, Joubert and others commit themselves unnecessarily to pseudoscientific statements about the creation and its history, which cannot rationally be defended. The incarnational model of Scripture focuses on the real message of God's word, rather than distracting and limiting readers through unrelated discussions on modern science. Thereby, Scripture is able to function in time and space, conveying the very breath of God to readers in all cultures and generations. Finally, it allows Christians specialized in the natural sciences to speak of God's creative work where Scripture simply has not. This—we pray—enlightens and informs our perception of the covenant God of Israel, who has made heaven and earth.

Understanding 'historical science', Ancient forests reconstructed

In the course of catching up on my normal reading, I picked out a couple of pieces to share with you from the Naturalis Historia blog:

Origins Science and Misconceptions of Historical Science

This article offers a brief and practical discussion on the false dichotomy Answers in Genesis places between "origins science" and "operational science"—the latter of which is supposedly characterized by repeatable experimentation. The implications of AiG's dichotomy is that all scientific inquiries into past events are treated as suspect, and the conclusions of such studies become susceptible to arbitrary rejection. Although AiG and other creation ministries devote much to the study of Earth history as they imagine it, they escape the 'limitations' of historical science by claiming access to the words of an eyewitness observer—namely, God himself.

From a philosophical perspective, however, the methodological distinctions between these forms of scientific inquiry are not justified. Both involve repeatable, 'laboratory' experimentation, though in the case of historical inquiries, 'nature' is our laboratory and the trials have already been run. Hypotheses regarding historical (or geological) events are testable so long as new observations and analyses can falsify the prevalent interpretation. The currently accepted age of the Earth (4.54 Ga), for example, is potentially falsifiable by 1) observations that demonstrate a unique origin of Earth relative to the rest of the solar system; 2) geochemical models that better explain how a Rb/Sr isochron built from ~7 dozen meteorite samples could have resulted from a phenomenon other than the passage of 4.54 billion years, and 3) evidence for the non-uniformity of laws governing subatomic particle behavior in the past.

Answers in Genesis faces a hermeneutical problem as well: nowhere does the text of Genesis claim to be an eyewitness account of Earth's beginnings. The highly imaginative language of Genesis 1–11 conveys its message through alternating concrete narrative and highly structured, semi-poetic prose. Earth's beginnings are described through phenomenological language, consistent with ancient views of the structure of the cosmos. As such, the text may communicate much truth about the nature of the cosmos, humanity, and of history itself, but precludes any detailed reconstruction of that history in modern, scientific language.

The literary approach of Answers in Genesis is, therefore, both theologically shallow and hermeneutically naïve. Granted, they may want to defend against my accusation. But one should note: they cannot do so without appealing to the results of historical inquiry, such as linguistic analyses of ancient Hebrew grammar/vocabulary, comparative literature studies of the Ancient Near East, or the textual transmission of the Hebrew Bible. In other words, they must employ a method that their ministry deems suspect to defend the notion that only an 'eyewitness' account of Earth's origins can reliably guide the historical sciences.

Still interested in how scientists study historical phenomena? Not convinced that AiG's dichotomy is in error? I highly recommend that you pursue this discussion by reading the Natural Historian's latest post, which offers a novel and wholly different approach than in my comments above. Moreover, you will find a range of additional resources on the same topic, from personal commentaries to peer-reviewed literature.

An Ancient and Alien Forest Reconstructed: A challenge for young earth creationism – Part I

Follow this link for one of several posts at Naturalis Historia commenting on the implications of a recent paper by Wang et al. (2012, PNAS), in which scientists reconstructed an ancient (Permian) forest that was buried in situ. Rarely do paleontologists get the opportunity to see habitats as they actually existed, since most evidences of ancient plants/animals are washed into sedimentary basins some distance from their 'homes'. However, volcanoes have a way of taking some rather intrusive snapshots (much like the historical Pompeii). The linked blog article provides the full-color figures from the original study, portraying the methodology and results of the forest reconstruction. Whether or not you are interested in the implications of this find for Young-Earth Creationism, the pictures alone are 'just plain cool'. I highly recommend that you take a look!

Squishy bodies, strange seas: the mystery of Burgess Shale-type fossilization explained?

The Proceedings of the National Academy of Sciences recently published a landmark, yet profoundly simple, report offering direct geochemical evidence of a viable mechanism for Burgess Shale-type preservation (Gaines et al., 2012). One example of such well preserved fauna (called Marella) is shown below:

Results of the international team's research, summarized here, suggest that soft-bodied fossils were preserved in the Middle Cambrian by a combination of favorable ocean chemistry and sedimentary 'sealing'. In short, oxygen-poor basins promoted the preservation of organic matter while scant sulfate concentrations inhibited microbial scavengers that thrive on bacterial sulfate reduction. The researchers also discovered thin laminae of lime cement (calcium carbonate) overlying the fossils. These laminae effectively would have 'sealed' the substrate in which the fossils were forming, thereby allowing organic tissues to decay at rates sufficiently low to be imprinted on the muddy layers of deep ocean sediments.

Mystery solved? Or perhaps, in more scientific terms: 'Mystery framed within a plausible hypothesis with replicated empirical support!'

Or so those pesky paleontologists and paleoceanographers would have us believe, according to Brian Thomas of the Institute for Creation Research. Not surprisingly, Mr. Thomas is skeptical of the described mechanism and reaffirms his belief that Burgess Shale-type fossils are instead evidence of "the Genesis Flood [and an] unprecedented scale of violent geologic activity" (read the full article here).

Violent geologic activity? These words don't seem to fit with the fine-grained canvases upon which the soft-bodied aliens of the Cambrian ocean were stamped. Therefore, I should attempt to explain his thought process. Let's begin by asking: 1) Why does Mr. Thomas reject the mechanism offered by Gaines et al.? and 2) What alternate explanation can he offer for these taphonomic anomalies (i.e. cases of exceptional preservation) and associated geochemistry? The answers are as deceptively simple as his interlocutors are profound.

1) Because he can, and thusly he misleads his readers. Mr. Thomas offers no substantive critique.
2) He does not, though he still pretends to.

I do not mean to be crass, but I am often discouraged by the ease with which Mr. Thomas and Young-Earth Creationist authors dismiss the latest research by misrepresenting rather basic geological observations and principles (see below). The tactic is not only dishonest, but leaves millions of readers—who place their trust in these authors—ill-informed and pursuing a false hope. Let's consider how Mr. Thomas approaches the work by Gaines et al. (2012):

"Marine biologists...never [find] fossils in the process of forming...because when a sea creature dies, its carcass is totally recycled within weeks. So, if a creature's soft parts are going to fossilize, it has to happen extremely fast."

Preservation of soft parts requires something wholly different than rapid fossilization. As Gaines et al. noted in an earlier publication (2008, Geology), the chemistry of Burgess Shale-type (BST) fossils indicates that fossilization did not occur rapidly (i.e. through early permineralization, or a replacement of soft tissues with other minerals). Instead, the process of organic degradation had to be slowed significantly. The most recent paper described independent evidence at multiple sites around the globe for this mechanism, confirming the original hypothesis.

Mr. Thomas continues by sarcastically recounting the authors' description of the mechanism by which these fossils were preserved. For example, he speaks of 'the assumed "global ocean" of the time', adding quotes unnecessarily to cast unwarranted doubt. He then asks:

"But did all that really happen? Probably not, since most of those events invoke unexplained phenomena, such as strange ancient sea chemistry and a puzzling absence of bioturbation. Plus, if sealing buried creatures under limestone explains Burgess Shale-type fossils, then similarly preserved fossils should be found beneath the continent-covering limestones all over the globe, and not just in isolated pockets."

The chemistry of the Cambrian ocean is far from unexplained, and I highly doubt Mr. Thomas is familiar with the plethora of research that currently describes our understanding of it. For example, the oxygen content of the Cambrian ocean is fairly well constrained through proxy evidence (chemistry of preserved minerals and organic matter) as well as geochemical modeling. I know partly because I have presented on the topic at geological conferences and contributed some data. Also well documented are evidences for low sulfate concentrations (less than 1/10th of modern values) during the Middle Cambrian. These explanations are neither novel nor unique to the conclusions by Gaines et al. (2012). However, they were not previously associated with BST fossilization.

Oxygen and sulfate concentrations may also be lower in deeper ocean basins restricted from rejuvenating circulation. Why is this important? Because it inhibits organisms from burrowing in the oceanic sediments! Where no oxygen is available, multicellular eukaryotes cannot survive, so their absence here is far from puzzling! Unless, of course, you posit that a global flood was responsible for the deposition of these rocks, in which case it is puzzling that burrowing animals are absent from layers where other animals are abundant.

Lastly, Mr. Thomas strains at credulity when reasoning that BST fossils should be found across the globe under limestone everywhere. As Gaines et al. point out, it is not the simple presence of limestone overlying mudstone that is significant, but the sudden deposition of calcium carbonate mud to seal off microbial scavengers in environments that also contain the aforementioned geochemical conditions. This only describes a tiny percentage of ocean basins in history. But how does the limey cement arrive in the first place?

"The study authors cited evidence of "rapid entombment" by "bottom-flowing density currents." And whereas standard geology has no explanation for such widespread catastrophic undersea density flows, creation scientists can cite the Genesis Flood in describing the unprecedented scale of violent geologic activity implied by these and other fossils."

I am shocked to read that Mr. Thomas believes geology offers no explanation for density currents (which actually occur on a daily basis around the globe, even in terrestrial lake systems!). A simple exercise, which elaborates my surprise, requires nothing more than GoogleMaps. My example (there are thousands more, which you ought to explore) comes from near Lompoc, California:

What looks like a pitchfork, connecting the shallow continental shelf to the deeper oceanic basin, is a network of submarine channels that formed by turbidity currents. Density flows form as a result of subtle differences in temperature, salinity, or suspended sediment load between adjacent water masses (see a fun video demonstration here). These bottom-water currents are capable of transporting calcium carbonate mud from shallow water to deeper basins. And—as Gaines et al. noted—they also provide a convenient trap to preserve soft-bodied fossils under favorable geochemical conditions.

To conclude, I urge you not to be misled by Mr. Thomas' swift, unwarranted dismissal of the latest research in Cambrian fossil preservation. Thusly, a great disservice is done to these fine examples of early life, preserved by an incredibly delicate process. Mr. Thomas' claim that BST fossil beds imply violent geologic activity is flatly wrong. Rapid burial alone cannot explain their preservation, and swift currents—along with the intense weight of overlying sediments—are not likely to leave such squishy bodies intact. Furthermore, Mr. Thomas offers no alternative explanation for the geochemical data reported by Gaines et al. (2012), generally interpreted to reflect Cambrian ocean chemistry and microbial activity.

His credibility is totally lost by saying simply 'No, this can't be right, because then I might be wrong.'

Don't miss the boat!

You may have noticed, things are currently on hold here. In the meantime, I am redirecting you to a guest post I authored, entitled "Don't Miss the Boat!" The (short) article was published recently on The Two Cities blog, which many of you will find a profitable resource on theology, biblical studies, culture, etc. The atmosphere is sufficiently casual to allow for friendly discussion of topics—some quite common, others even controversial—but written by very capable and credentialed, young academics. I encourage you to look around.

Please feel free to share your comments regarding my article (here or there), but do note the following points to avoid some common misconceptions.

1) Despite the subtitle of the article (which was added by the editors), my aim was not to discuss the historicity of Noah's ark. Rather, I am focused on whether the obsession by some over this historical-critical question has unnecessarily divided the church and caused many to miss our real vocation.

2) The points I make do not commit to any particular stance on the historicity of Noah's ark. I do note in passing that there is no geological evidence for a recent global flood, but it is possible to agree with my thesis/discussion while disagreeing about the geological evidence. Obviously, that scientific question is more involved than 800 words can offer. Hence, this blog (among others) is filled with long, detailed discussions on the geological evidence to support my claim.

3) In saying that "the historical question is not primarily A, but B", I am not proposing a simple dichotomy between A and B (hence my use of the term 'primarily'). I understand that the question of the historicity of Gen. 6–9 is still valid and cannot necessarily be divorced from, say, the theological application of this story to redemptive history. My main point is that we should at least agree on how/whether the story speaks to our vocation today before marginalizing ourselves (perhaps unnecessarily) from most of modern society.

Enjoy! Hopefully I will be able to continue my thoughts here in the next week or so.