Category Archives: Digressions

Marie Tharp and the mid-Atlantic rift; a prelude to plate tectonics

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Map of North Atlantic mid-ocean ridge

The history of science is littered with the misplaced contributions by women, contributions that at best were pushed aside or ignored, and at worst thought of as shrill outbursts. Witness Rosalind Franklin’s fraught journey to DNA’s double helix, the recent unveiling of Eunice Foote’s experimental discovery of the greenhouse effect of CO2, and Bell Bernell’s discovery of pulsars, as corrections to a history where women found it difficult to escape the status of ‘footnote’. We can add Marie Tharp (1920-2006) to the growing list of corrections. In 1952 Tharp discovered the central rift system in the mid-Atlantic Ocean ridge (that later would become a critical component of sea floor spreading and plate tectonics) but for many years was regarded as a minor player in the burgeoning, post-war field of oceanography.

During the War, Tharp in her early twenties took advantage of opportunities to engage in university study, openings in science and engineering left by men who had gone to battle. She completed a Master’s degree in geology, but given that geology is a field-based discipline, and that women weren’t supposed to go into the field, she extended her studies to a Master’s in mathematics. In 1948 Lamont Geological Laboratory (now Lamont Doherty Earth Observatory) hired 28 year-old Tharp to draft maps of the Atlantic ocean floor, based on the growing database from SONAR and historical soundings. She worked with well-known geologist-oceanographer Bruce Heezen, who spent much of his time at sea. It must have been tedious work, but she counted herself lucky to have a position at all. This was a time when very few American universities (or anywhere else for that matter) offered science and engineering positions to women; a time of patriarchal condescension – “Mad Men” versus “Hidden Figures”.

 

description of SONAR
Tharp poured over depth and positional data for years, constructing 2-dimensional profiles of the Atlantic Ocean floor. She was aware, as other oceanographers were that an elevated region of sea floor apparently separated east and west Atlantic. This was initially mapped in 1854 by US Navy oceanographer, geologist and cartographer Matthew Maury, and later confirmed with depth soundings taken during the HMS Challenger expeditions (1873-1876 – Challenger had 291 km of hemp onboard to do this kind of thing; the ridge is generally deeper than 2000m). Tharp wasn’t surprised to find the Atlantic ridge on her profiles. What did catch her attention was the rift-like valley in the central part of the ridge; a geomorphic structure that was consistent through all her profiles. She immediately recognized the importance of this, because it implied significant extension, a pulling apart of Earth’s crust in the middle of the ocean. At the time, the general consensus was that ocean floors were relatively benign, featureless expanses. Her discovery indicated otherwise.

 

bathymetry profiles mid Atlantic

According to Tharp’s bio the response by Heezen and his colleagues was that she was being a typical woman – you know, “girl talk”. One can imagine the coffee room banter; ‘she’s great at drafting cross-sections but should leave the interpretation to the more learned’.

However, after some months and more profiles all showing the same rift- like structure, Heezen gradually accepted that this was real. A turning point for Heezen was the coincidence of several mid-ocean earthquake epicenters along the ridge. This was mid 1953. He understood its potential significance, particularly for those who thought that the hypothesis of continental drift had some credence (Heezen was not initially one of those people).

Ocean bathymetry studies in other basins in the early 1950s (Indian Ocean, Red Sea) revealed similar mid-ocean rifts. Tharp had by this time surmised that a rift valley coursed its way almost continuously the entire length of North and South Atlantic, a distance of 16,000 km; it was the largest continuous structure on Earth. The Lamont Doherty group gradually realized that the Atlantic structure, together with those discovered in other ocean basins, represented a gigantic Earth-encircling system of mid-ocean rifts, more than 64,000 km long.

Heezen presented their research to a 1956 American Geophysical Union conference in Toronto. Marie Tharp barely received a mention. She did co-author a few subsequent publications as an ‘et al.’, but it was a kind of ‘also ran’; the accolades and approbation went Heezen’s way.

Tharp was fired by the Laboratory, the victim of a spat between Heezen and Lamont boss Maurice Ewing, but she continued to develop the maps at home. Marie continued to work in the background, as the humble and grateful recipient of a job she considered to be fascinating; “I worked in the background for most of my career as a scientist, but I have absolutely no resentments. I thought I was lucky to have a job that was so interesting”.

Marie Tharp and Bruce Heezen

Marie Tharp was named one of the four great 20th century cartographers by the Library of Congress in 1997, was presented with the Woods Hole Oceanographic Institution Women Pioneer in oceanography Award in 1999, and the Lamont-Doherty Heritage Award in 2001.

There is no question that Tharp’s discovery influenced the promotion of Continental Drift in the geoscience community. Alfred Wegener’s bold hypothesis (1915) had one major problem – there was no known mechanism that could move oceanic crust and continents around, like some precursor shuffle to a jigsaw puzzle. In 1929 Arthur Holmes posited a mechanism that involved large convection cells in the mantle, but this too lacked an important degree of empirical verification. Discovery of the mid-Atlantic rift provided a solution to this vexing problem, and in 1962 Harry Hess proposed that new magma, via mantle convection cells, was erupted from mid-ocean rifts allowing oceanic crust to spread outwards. This was Sea Floor Spreading, a precursor to the grand theory of Plate Tectonics – the tectonic shift in geological thinking wherein oceanic crust is created at mid-ocean rifts and consumed down subduction zones, with the continents playing tag.

Marie Tharp’s doggedness in her belief and understanding of mid-ocean rifting is now celebrated. It’s taken a few decades, but she is no longer a footnote.

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Bluebottle entanglements; or how to ruin your day at the beach

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The southern hemisphere is coming into summer; it’s done this every year for as long as I can remember. For New Zealanders, and pretty well anyone else in this ocean-locked world there is an exodus, a migration as the population ups-sticks and heads to the beach. Unlike our nearest neighbour, we are not thwarted by crocs, sea snakes, Stone Fish or Box Jellyfish; Great Whites mostly ignore us. From the point of view of dastardly critters, these shores would be considered benign. Except for Bluebottles.

Bluebottles galore; entanglements that can ruin a perfect day at the beach (soft, squishy and potentially dangerous).  There are thousands of Bluebottle stings reported every year in New Zealand and Australia. Bluebottles are related to jellyfish, a very pretty blue, puffed up balloon-like, stranded along the high tide line, bedraggled. These creatures, delicately laced, frequently litter NZ beaches (and elsewhere), blown ashore on the tide.

Bluebottles belong to a group of marine animals (a phylum) called Cnidarians, a group that includes corals, sea anemones, true jellyfish, and siphonophores. They all have stinging cells (nematocysts), although corals, sea anenomes and many jellyfish tend to be relatively benign – except to the small critters they like to eat.

Bluebottles are not Jellyfish, they are siphonophores. A true Jellyfish is a single organism, a medusa that possesses a central gut and nervous system; they are all free swimming (Sea Anemones also are single organisms, consisting of a polyp attached to rock, shell or sediment).  Bluebottles are colonial organisms containing a myriad, microscopic, multicellular animals, or zooids, that find solace in community living. Despite being individuals, zooids are attached to and dependent on each other. Zooids tend to have specialized functions; some are attuned to digestion, others to swimming or carrying nematocysts in the tentacles .

The two most common species are Bluebottles that inhabit the Pacific and Indian oceans (the species Physalia utriculus), and the Atlantic (Physalia physalis), the latter more commonly known as the Portuguese Man o’ War (see image at the top of this post).  Both have an easily identifiable gas-filled bladder (pneumatophore) in an attractive blue with hints of mauve, from which dangle tentacles – the things do the damage to passing small fish and people. The bladders provide the only means for movement by catching wind and waves (again, unlike Jellyfish that propel themselves).

Portuguese Men o’ War tend to be larger than their Pacific cousins, with tentacles extending 10m, and even 30m below the sea surface.  Bluebottles have smaller pneumatophores, and fewer and shorter tentacles. The tentacles contain many stinging cells called nematocysts; their sole function is to catch and stun prey. Nematocysts on Bluebottles and Portuguese Men of War can penetrate skin to inject venom. A single stinging cell will do little damage. Unfortunately, tentacles tend to wrap their prey (including arms and legs), in an act of evolutionary hubris that inflicts multiple stings manifested in a nicely symmetrical, cork-screw like pattern of welts.

Bluebottle stings are painful- I can attest to this. In most people, this is as far as it goes, but if you are unfortunate to have tentacles wrapped around large areas of your semi-naked body, the venom can induce nausea and headaches, and in more serious cases, difficulty breathing or cardiovascular failure (happily the latter are rare).

There is plenty of advice on how to deal with Bluebottle and Portuguese Man o’ War stings. First and foremost, don’t try to rub or scrape off the tentacles; this will only exacerbate envenomation. Use seawater to wash thoroughly the affected area. Some authorities recommend dabbing vinegar on the welts to help ease the pain; others suggest this only makes matters worse (this link is an Open Access document). I must admit, a bottle of vinegar is not usually on my list of things to take to the beach, unless I’m planning to cook shellfish.

There is also the mistaken belief that peeing on the affected area will help. Urinating on oneself might be awkward, so you would probably need a willing accomplice.  But the real kicker here is that pee makes the nematocysts release more venom. So, if anyone suggests this remedy, do let them know it is nonsensical, notwithstanding the public spectacle. Tentacles can also release venom long after they have been blown ashore.  So it’s best to admire them from a distance.

Enjoy summer.

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Crème brûlée, jelly sandwich, and banana split; the manger a trois of layered earth models

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Some things in science are just too difficult to comprehend: the temperature at the center of the sun (15,000,000oC), the age of the earth (4.6 billion years), the size of a nano-particle (1-100 nanometres, or billionths of a metre). We can include in this list of imponderables, the skinny outer layers of the earth: the one we are in daily contact with (the crust), and other layers beneath it. Our familiarity with the crust is usually in terms of the dirt, rock, and water we work with. But what is it like 30km down? And, beneath the crust, the upper mantle is beyond reach of our senses. What does this layer look like? How does it respond to being pushed around?

Some scientists (geologists, geophysicists) spend a great deal of time pondering questions like these. The crust and upper mantle layers are collectively referred to as lithosphere. Beneath the continents it averages 150 km thick; beneath the oceans, it is as thin as 10 km beneath the mid-ocean ridges. Given we spend our entire lives on the uppermost veneer, a reasonable person might ask ‘why is it important?’.

A few common answers include: Most earthquakes are generated in the lithosphere; Magmas erupted at volcanoes melt at these depths. But the overarching reason is that all tectonic plates are born and destroyed as lithosphere. Plate tectonics governs pretty well everything that happens on earth over geologically short and long time-scales. So, what appears arcane at first sight, does have practical applications.

Enter the dessert trolley. There are three choices: a crème brûlée, a jelly sandwich, and a banana split. Proposed as models of the layered earth, they serve a dual purpose: they provide visual descriptions of how the lithosphere might be structured and, after evaluating the merits of each, they can be consumed.

The crème brûlée is a two-layered model.  A viscous fluid base (custard) is capped by a thin crust of caramelized sugar. The crust behaves in two ways. Poke it gently in the centre, and it will bend slightly – release the pressure and it will return to its original shape.  This represents elastic behaviour (think also of wire springs, or rubber bands). Press it too hard and it will break into several ragged pieces; in this instance, you have exceeded the elastic limit, or strength, and induced brittle failure. Earthquakes represent brittle failure where earth’s crust fractures, is displaced, and in the process causes mayhem. The crème brûlée model is probably the simplest of the dessert trio in terms of its relevance to the lithosphere.

The jelly sandwich is potentially the more variable of the three analogues. It is a three-layered model where two pieces of bread are separated by a layer of jelly.  Here, the upper bread layer represents a strong upper crust, and the jelly a weak lower crust. The bottom bread layer is compared with a strong upper mantle – in contrast to the weak custard (mantle) layer in the crème brûlée. The upper and lower bread layers are both quite bendy (unless you have toasted the bread). If you use plain white bread, then bending will be uniform. But if you prefer whole-grain slices there will be lots of lumps and greater heterogeneity, and hence a less predictable response to the application of pressure, or stress. The jelly is much less fluid than custard. It can behave elastically – witness the wobbling, that represents deformation from which it recovers, but at a certain point it too will fail.  Bread is less rigid than a crème brûlée crust; any kind of twisting or bending will probably result in some permanent deformation (i.e. it doesn’t bounce back to its original shape). Unlike the crème brûlée crust, bread is less prone to brittle failure.

The banana split adds another level of complication to models of the lithosphere. The rationale for this model is that the lithosphere contains zones of weakness, particularly near the boundaries of tectonic plates – imagine these plates colliding or sliding past one another, where the forces are large enough to create mountain belts and consume oceans. Here, scoops of ice-cream represent blocks of crust and mantle that are separated by large, very deep faults. This is a very temperature-dependant model. As the ice-cream melts there is a zone of weakness between it and the adjacent scoop (block). The presence of fluid, particularly water, exacerbates this weakness. In this dessert, we need to translate the fluid boundary between scoops of ice-cream, to structures 10s of kilometres deep. Modern examples include the Alpine fault in New Zealand, and San Andreas Fault in California. Some of these large structures can last for very long periods of geological time (100s of millions of years), and potentially influence events in the crust-upper mantle long after they first formed.

All models in science are simplifications of the things we try to explain. It may be the case that some consider the dessert trio to be trivial, even silly, providing little useful scientific information for the representation of the crust and mantle.  But the utility of models and analogues is not only in scientific explanation, but to present a complex world in visually interesting, and yes even amusing ways. Models and analogues need to stir the imagination of folk who are not directly involved in this kind of research but have a vested interest in it. In this regard, the dessert trio works, even if folk can relate to them only via our taste buds.

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A chance encounter with James Ussher, circa 1650

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A chance encounter of a different kind. The 9th century Book of Kells is exhibited in the Trinity College library (Dublin). The book contains 340 sumptuously illustrated folios written on vellum (calf skin), that make up the four Gospels (the entire book can be viewed online). It was written and illustrated around 800AD, in either Iona (Argyllshire, Scotland) or Kells (County Meath, Ireland), and possibly both. Monks from the St. Colum Cille Monastery in Iona, fled to Kells in 806 to evade further slaughter by marauding Vikings (who seemed to have a penchant for religious orders). Hence the uncertainty surrounding the location of the Book’s compilation.

Two or three folios are exhibited at any one time in the library.  There is something special about seeing this, regardless of one’s beliefs. That a document this ancient has survived pestilence, religious and political purges, plundering and the general ravages of time, is a testament to the enduring belief that human history is worth preserving.

A visit to the Book of Kells exhibit eventually leads to the Long Room, a cathedral-like hall with high barrel-vaulted ceiling dedicated to preserving old and ancient manuscripts, tomes, letters and assorted documents. It was first built in 1712) but enlarged in 1860 to accommodate a burgeoning collection.

One of the College’s 17th century benefactors was James Ussher, Archbishop of Armagh (although he never lived to see the actual Long Room). He was instrumental in purchasing books for the then nascent College library. Ussher became famous, or infamous, for his dating of Genesis creation at October 23rd, 4004 BC. He based this calculation (published in 1650) on biblical genealogies and historical events. Given what we now know about the age of the earth, Ussher’s calculation is generally viewed with a mix of ridicule and begrudging respect.

Acting on a hunch, I asked one of the library attendants if any of Ussher’s books were available for viewing. He suggested I check with the folk in charge of ‘reading room’ passes. This took a while but I was eventually issued a pass and ushered (sic) to the reading room. The first task was to search the catalogues.  One index of books had an entry annotated with scribbled comments on “creation dates”. Bingo. This particular volume appeared shortly thereafter in its own protective box. A rather plain unassuming book was placed carefully on a special reading rack. Instructions were given on how to turn the thin, brittle, dog-eared pages.

The journey through 400 year old documents like these is more one of personal discovery than some momentous event of universal import. The book was a collection of Ussher’s notes, annotated texts, and the odd piece of correspondence. Flicking through these pages gave, for a moment, a view into Ussher’s thinking. Here were his working notes, in a mix of Latin and English. Marginal scribblings on printed text and fragments of scripture, ecclesiastical compositions, calculations of cumulative dates gleaned from the scriptural register of births and deaths, crossings-out and corrections. Here was a person, a Bishop of repute, who tried genealogical combinations, recognized errors, approximated, and perhaps even fudged the odd date. Maybe there were even doubts about the progression of time.

The opportunity to look at Ussher’s notes came out of the blue. It was worth the multiple forms I was required to sign, acknowledging Trinity College’s copyright. I took photos of the text, but cannot display them. What a shame. A 400 year-old document originally intended to be read by all and sundry, now (figuratively) locked away by some arcane law (unless I payed a fee). I don’t decry all copyright conditions, just this one, that applies to a document written by a person who probably never intended such conditions of ownership to apply.

We now know that Ussher’s date for the beginning of earth history has a rather large margin of error. As absurd as his date may sound, it was derived from serious scholarship, in a manner we would now call ‘multidisciplinary’. This in itself is something to celebrate.

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Bishop James Ussher, and the beginning of everything

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In 1650 AD/CE, James Ussher, Bishop of Amargh and Primate of all Ireland, published the scholarly “Annals of the Old Testament, deduced from the first origins of the world” where he concluded that the universe, and everything in it, began at noon, October 23, 4004 BC. To many modern scholars of the earth, this seems outlandish, even ridiculous. Creationists though still attest to its veracity.

It is easy to fall into the trap of judging old ideas with modern concepts and proofs, rather than judging them according to the precepts and traditions of their day; of course, the real kicker here is that one needs to have some knowledge of those cultural contexts and traditions. I was reminded of this during a re-read of Stephen J. Gould’s Fall in the House of Ussher (Natural History, 1991). In an early paragraph Gould writes “To this day, one can scarcely find a textbook in introductory geology that does not take a swipe at Ussher’s date as the opening comment in an obligatory page or two on older concepts of the earth’s age (before radioactive dating allowed us to get it right). Other worthies are praised for good tries in a scientific spirit (even if their ages are way off), but Ussher is excoriated for biblical idolatry and just plain foolishness. How could anyone look at a hill, a lake, or a rock pile and not know that the earth must be ancient?” (Gould often used diverse ‘lead-ins’ to his essays, the pithy import of which don’t become apparent until one is well into the reading).  It is basically a statement about making judgements.

Confronted by a “hill, lake, or rock pile”, you try to imagine how long it took to get there. Your cogitation will go no further, from the point of view of actual explanation or some empirical value, unless you also happen to know about geological and geomorphic processes, their short-livedness or longevity. Without this knowledge, a priori, the longevity of this pile of rock will remain a mystery. For Ussher, this kind of knowledge was not part of his paradigm, his view of the universe.  Quite the opposite; his view was imbued with a theological tradition that was still trying to deal with the monstrous notion that man and earth were not the centre of the universe. Galileo’s excommunication had taken place a mere 17 years earlier.

Ussher lived and rationalised the universe in a tradition of theological doctrine, a tradition imbued with a belief in divine intervention. He was admired at the time as a scholar, who impressed the nobility so much that on his death in 1656, Oliver Cromwell ordered him buried at Westminster. The starting point for Ussher’s Old Testament genealogy was the death of King Nebuchadnezzar II (634-562 BC/BCE) of Babylon; from there he worked back through the generations to Adam, using a combination of biblical patriarchy and secular history.

Ussher was by no means the first to calculate a creation time-line. Luminaries like the Venerable Bede (672-735), who counted all the begets and begots in Genesis, traced creation to 3952 BC. Even Isaac Newton and Johannes Kepler, two giants in the history of science who we tend to associate with the rise of empiricism, concurred that 4000 BC was not just a nice round number but had meaning as the beginning of everything, based on biblical and secular histories. However, it was Dr. John Lightfoot, Chancellor of the University of Cambridge no less, who in 1642 used biblical genealogies and classical history to calculate the beginning at 9am, October 23, 4004 BC. October the 23rd was a Sunday (appropriate) and close to the autumnal equinox. Ussher must have been aware of Lightfoot’s work, and some historians have suggested that there was a degree of one-upmanship between the two academics. One historical footnote has even suggested that Lightfoot’s addition of “9 am” to the October 23rd date, was inserted after Ussher’s 1650 publication in a fit of academic pique (I guess some things haven’t changed).    Lightfoot’s work is now little more than a historical footnote to Ussher’s opus.

Following Ussher’s publication, The King James Bible (first completed in 1611) added dates to the margins of Old Testament scripture. Thus, “In the beginning…” (Genesis 1:1) has the margin note ‘4004 BC’, and the date Noah’s ark became stranded on Mt Ararat “May 5, 1491 BC. The annotations have been attributed to Ussher rather than Lightfoot, perhaps because he was in court-favour at the time. Use of Ussher’s dates in marginal notation continued in some published Bibles into the 20th century.  Perhaps the whole idea of a creation time-line needed a personality, and James Ussher was it.  Ussher’s legacy is that he still bears the brunt of the creationist claims of a ‘young’ earth, and a tendency to denigration from the scientific community who know how old earth really is.

And this is the central theme of Stephen Gould’s complaint. We now know earth is about 4.6 billion years old; this knowledge derives from radiometric dating of the most ancient earth rock, meteorites, and moon rocks.  But this knowledge was established only in the last half of the 20th century. Earlier estimates of the age of the earth (and solar system) through the 19th century, ranged from a few 100,000 to 300 million years (e.g. Charles Darwin, Charles Lyell, Lord Kelvin). All these early calculations by learned folk are taken (as they should) to be the best estimates at that time, given what was known about earth processes. The calculations were scholarly, and for the most part, well considered. We don’t ridicule them, simply because we now know them to be incorrect (radiometric dating methods were not part of the geologists’ toolbox until the early 1900s).

Likewise, Ussher and Lightfoot used, in a considered fashion, the information available at that juncture of the 17th century – the genealogies in biblical scripture and classical history. Galileo and Copernicus had certainly rocked the boat in terms of humanity’s place in the universe, but not its longevity. In the 17th century, the only way to decipher time past was through written history, or a vivid imagination.

According to the Old Testament, there were 75 generations between Adam and Jesus, and if we assume that each lived 50 years (with overlap of first-born sons – sorry, but it was all about the patriarchy back then), some quick, back-of-the-envelope arithmetic gives us about 3000-4000 years from creation. And again, if we treat the 6 days of creation as a kind of metaphor, where ” For a thousand years in thy sight are but as yesterday when it is past, and as a watch in the night” (Psalm 90, King James Bible), then 6000 years gives an upper limit for Day 1. These dates became ingrained in Renaissance and Enlightenment Christian views of the universe. For some in the 21st century they are still ingrained.

By all accounts, neither Ussher or Lightfoot were charlatans; they did not take all those BC genealogies through arcane twists and turns to prove a point (something modern Creationists are quite good at).  They were not trying to disprove science. No doubt there were errors of interpretation, and perhaps errors of omission.  There were certainly difficulties in aligning events according to the Julian, Gregorian, and Hebrew calendars, as Gould and other scholars have pointed out.

We often think of the Enlightenment as the beginning of modern science, but in the 17th century it was still nascent, and in a state of almost continuous tension with approved church doctrine. Ussher and Lightfoot may have been sympathetic with the emerging science (I’m not sure historians really know this), but they were also immersed in theological tradition. They took the information that was available and used it in a scholarly fashion.

So, next time you hear someone disparage Ussher and his colleagues, remind them that cultural, philosophical, political, and religious contexts are important when judging historical events. It is also worth keeping in mind that, 100 years hence, theories and hypotheses that today have scientific value, may send future generations into paroxysms of laughter.

Footnote: The historical annotations CE (Common Era) and AD (Ano Domini) refer to dates since the first year of the Gregorian calendar. Thus, BCE is before the common era, and refers to the same dates as BC (before Christ). The difference between the older BC/AD and recent BCE/CE notations is that the latter has no Christian connotations.

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In the field: from one extreme to another

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Have you ever looked at some locale on a map or photograph and thought “that looks like an intriguing place to work”, only to find, sometime later that you are smack in the middle of that same spot?  Time-warp? Some god’s lap?

I was preparing to travel to Canada. The plan was to do a PhD, and because I had not long completed a Masters thesis on geologically very young sedimentary deposits, had entertained the idea that research on very old rocks would add a kind of symmetry to my geological outlook – from one end of the geological time-scale to the other.  In preparation, I borrowed The Geology of Canada, a weighty tome, and homed in on the Precambrian system (basically everything older than 540 million years).  What caught my attention were some squiggly-shaped islands about 150km off the southeast coast of Hudson Bay; the Belcher Islands.  Their shape belied some interesting geological structures, and the strata a mix of sedimentary and volcanic rocks about 2 billion years old. What a neat place to work, although I envisioned the islands to be treed.

I arrived in Ottawa (early January, 1976) to minus 25oC and snow; I had never seen so much snow. I thought it quite beautiful, which elicited wry comments from the Ottawans I was meeting who were sick of shovelling driveways and digging vehicles out of snow drifts. Destination – Carleton University. My supervisor was to be Alan Donaldson, well-known in Precambrian geology circles. Following the introductions, he announced that my project, unless I had some objection, was to focus on the Belcher Islands.  LOL. I was to spend 5 months there in total over the summers of 1976-77.  The social environment, the weather, and the geology were remarkable.

Getting to the islands was a milk run: a drive to Montreal airport, a flight to Moosonee near the southern shores of James Bay (northern Ontario), a very noisy DC3 leg to Umiujaq (Quebec) where we picked up field equipment (kindly loaned to us by the Geological Survey of Canada), then Twin Otter across the 150 km to Sanikiluaq, the sole village on Belcher Islands. We were able to stay in a small house owned by the Hudson’s Bay Company for the two days needed to sort gear, buy food, and make sure the two inflatable Zodiacs and outboards worked. My assistants (John McEwan in 1976, Mike Ware in 1877) and I always used two boats as a safety measure (and for visitors).

The seas around the islands are mostly ice-free during the summer months, but the water is still only a few degrees above freezing, and the air close to the water cold. Even in the summer, we had to bundle up with wet-gear, fleeces, and life jackets (I was told the life jackets were necessary for insurance purposes – so they could retrieve the bodies). The islands and intervening channels are also elongated north, so that wave set-up could change drastically any time there was a wind shift.  We were caught out a few times with unfavourable seas, but there was always somewhere to shelter.

Belcher Islands are mostly held together by a thick volcanic unit that creates more or less linear coastlines. The strata were folded, like a series of waves, into simple anticlines and synclines, such that the package of sedimentary rocks is exposed in the anticlines, while the synclines are drowned by major channels and inlets.  The terrain is subdued with low relief – the islands were scraped clean by the Laurentide Ice Sheet during the Last Glaciation.

Our base camp was to be in a small, relatively sheltered inlet along the western shore of Tukurak Island (one of the largest and easternmost island).  It was a 3-4 hour journey, depending on weather.  This is the site of an abandoned Hudson’s Bay post. It was also the favoured summer holiday spot for local Inuit, primarily because it is close to their source of soapstone.  Belcher Island soapstone has an enviable reputation amongst northern communities, because of its uniform, deep green colour, and general lack of fractures that would render carving difficult. Whenever we were in base camp, we would watch the elders carving, and teaching their younger folk the same skills. They would also bring us bannock and Arctic Char. And there was never a shortage of Inuit kids around, checking in, telling stories, or simply hanging out. We would spend 4-5 days away from base camp, returning to stock up and cache samples. Time in base camp was always a delight.

Belcher Islands sit well below the Arctic Circle at 56oN (latitude), and yet the landscape is typically Arctic. The northern Canada tree-line is located south of Hudson Bay, such that the Islands have a typical Arctic flora (especially wild flowers), and no trees – so much for my earlier, wistful image of the place.

The weather alternated between gorgeous, with light winds and clear skies, and abysmal. On more than one occasion we returned to camp from a day’s work to find tents down and sleeping bags soaked.  High winds also prevented longer excursions with the boats, unless we were riding through sheltered channels and inlets.  With the boats, there was always one eye kept on the weather.

During the first couple of weeks in 1976, Bill Morris (Geological Survey of Canada) had joined us to sample rocks for geophysical measurements (looking for ancient magnetic poles). The day he was to leave base camp (and fly out of Sanikiluaq) was particularly inclement. He insisted on attempting the trip, but instead of using our inflatable boats, I decided to rent one of the larger, sturdier, Inuit canoes with twin outboard motors (I was the only one with boating experience). We ventured out of the sheltered inlet, into the maelstrom – at least that’s what it looked like from the perspective of our small craft. I doubt we got any further than 50m from the inlet entrance; a lull in the waves, a quick decision to about-face, a beeline back to calmer waters, and the colour returned to the faces of my two passengers.

“Guess I’m going to miss my flight”. We all new he probably would have missed it, even if we had continued. Back to base camp to drain what was left of a bottle of scotch, and cogitate on an earlier field season on a warm New Zealand Pacific coast.

This is the first blog on my Belcher Islands episode

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In the field: Beaches, sand dunes, and shellfish for lunch

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Final exams over, a moment of tomfoolery, and I found myself disconsolate in a hospital bed, recovering from an operation on a dislocated knee (no such thing as key-hole surgery back then).  I had completed my BSc (November,1972) and was contemplating doing a Masters on something sedimentological. A visit from one of my professors, a period of impatient recovery, then loaded the aging Morris Minor and headed north almost as far as it is possible to drive in New Zealand. This was to be my first bona fide field project.

My field area incorporated a 22km stretch of glorious coastline that, at its northern extent, culminated in a sandspit (Kokota Spit) and Parengarenga Harbour. The task was to decipher the sand deposits, from the very recent to maybe a million or so years old. This narrow strip of land is part of the much larger Aupouri Peninsula, founded on sandy bars and spits that connect small islands and headlands of harder, older igneous and sedimentary rock. Tasman Sea washes the west flank of Aupouri, and the Pacific the east; the two seas meet at Cape Reinga, the place where Maori spirits begin their new journey. Continue reading

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A Murex tattoo

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The Saturday Evening Post, March 4, 1944, featured on its cover the iconic Norman Rockwell portrait of The Tattoo Artist. The artist (a friend of Rockwell’s), his backside bulging towards the viewer, has crossed out the names of former loves and is in the process of immortalizing ‘Betty’ on the arm of a grateful sailor. The fickleness of love permanently inked on its next port of call.  A simple picture at first glance, but imbued with all kinds of hidden meaning: personal goals or conquests, the lighter side of global conflict, the personal choices one makes in life and their consequences (intended or otherwise), and the role of so many different tattoo motifs as symbols, metaphors, or memories. Continue reading

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Hold a ‘0’ to the light and look through it – there is nothing, and everything

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Several years ago I read Jerry P. King’s The Art of Mathematics (1992). Chapter 3 deals with Numbers, and in it is a statement that has bothered me ever since “Although they are the most fundamental of mathematical objects, the natural numbers are not found in nature.” There are real numbers, but none exist in the natural universe. We may count two people, write the number on a piece of paper, or solve an equation that gives the answer as two, but the number ‘two’ does not exist – we cannot pick it up or put it under a microscope. I have kept an eye out for ‘one’, but even this basic singularity is elusive. Numbers, it seems, are an abstraction.

So where does this leave ‘zero’? Zero means nothing, zilch, emptiness; so is it even a natural number – is it an integer? Several commentators of mathematics and science have suggested Continue reading

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In praise of field work

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The class field trip is underway.  Teacher hands out the rap-around, virtual imaging glasses, and you are transported to a green horizon. In the background, there is an annoying kind of buzz, as teacher relates the topic of enquiry, asks questions, provides comments. Fellow students may even be projected into your virtual reality, their essence reduced to pixels. There’s a resounding crash – one student, suffering from vertigo, has fallen off their chair. Another has just thrown up from motion sickness.  All in a day’s field study. Off come the glasses. The green horizon vanishes. All except one of your classmates are still in their chairs, surrounded by the same four classroom walls. What was learned? Continue reading

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