Author Archives: linarite

New clues to origin of porphyry-type ore deposits

The prominence of porphyry Cu-Au-Mo deposits above active subduction zones at continental margins, as in the Andes, has long encouraged ore geologists to suggest that they form as part of continental arc magmatism. Typically they occupy cupolas above large, intermediate to felsic, subvolcanic magma chambers that source the ore-forming fluid and most of the metals. Most show evidence of the influence of explosive fluid boiling that shatters the host porphyry mass during late stage hydrothermal activity thereby producing myriad cracks that become mineralised as a stockwork. One of the largest, among the longest worked and most investigated porphyry deposits is that at Bingham Canyon in Utah, USA. New isotope geochemistry bucks the accepted wisdom about porphyry-type mineralisation, in particular the source of the contained metals (Pettke, T. et al. 2010. The magma and metal source of giant porphyry-type ore deposits, based on lead isotope microanalysis of individual fluid inclusions. Earth and Planetary Science Letters, v. 296, p. 267–277).

The Bingham Canyon ores and host intrusion are Cenozoic in age (~38 Ma). However, isotopes of lead in fluid inclusions within the ore zone reveal a much more ancient metal endowment of the mantle underlying continental crust, around 1800 Ma ago, probably by metasomatism during the accretion of Palaeoproterozoic island arcs. Magmatism in the late Eocene, presaging the evolution of the Basin and Range extensional province drew in Cu and Au from the mantle and Mo from assimilated continental crust; i.e. Bingham Canyon and other huge porphyry deposits of the Western USA inherited metal enrichment from long beforehand, unlike those of active continental arcs. The intrinsic importance of the discovery is that given intermediate to felsic magmatism of any age, if it is sourced in relics of earlier arc-related igneous events then there is a chance that more recent activity may spawn rich porphyry deposits; more or less anywhere, given a metal endowed infrastructure. That opens up exploration possibilities to hitherto unexplored ground above ancient subduction zones.


Earlier colonisers of northern Europe

The Pleistocene of East Anglia in England is a rich source of the high-latitude flora and fauna from early interglacials of the 1 Ma long series of 100 ka climate cycles. Eyed by archaeologists for decades as a potential source of human remains, a coastal site at Pakefield in Suffolk finally yielded stone tools in 2005 (see Earliest tourism in northern Europe in EPN January 2006). The enclosing sediments, to widespread excitement, turned out to be around 700 ka old, establishing the earliest known human colonisation at that latitude (52ºN). At that time East Anglia was connected to Europe during both glacial and interglacial periods, and was crossed by a now-vanished river system draining the Midlands and Wales into the proto-North Sea. Stone artifacts have now emerged from similar interglacial terrestrial sediments on the shore below the village of Happisburgh (pronounced ‘Haze-burra’) further north still, in Norfolk (Parfitt, S.A and 115 others 2010. Early Pleistocene human occupation at the edge of the boreal zone in northwest Europe. Nature, v. 466, p. 229-233). Magnetostratigraphy pushes back the human influence here to more than 800 ka, maybe as far back as 950 ka. As yet no human remains have been turned up, and the site is below high-tide level and liable to be destroyed by winter storms so work proceeds as fast as possible. Yet cliff erosion will inevitably reveal new material each spring.

Fauna and flora from Happisburgh indicate a slow flowing river flanked by coniferous forest with grassed clearings. Beetle fossils suggest summer temperatures slightly warmer than those in modern southern Britain, but with winters some 3ºC colder than now. The climate was analogous to that in southern Norway today, at the transition from temperate to boreal vegetation zones; certainly tough in winter for people without shelter. Yet the permanent connection with continental Europe would have permitted easy seasonal migration across great plains that extended to warmer southern climes. The tool-using people were not the earliest Europeans, for several archaeological sites in Spain, southern France and Italy extend back to 1.3 Ma. Who or rather what hominin species they were needs bones, preferably those of the head. The discovery that there were at least 4 hominin species cohabiting Eurasia during the last glacial epoch encourages caution in any speculation.

See also: Roberts, A.P. & Grűn, R. 2010. Early human northerners. Nature, v. 466, p. 189-190.

Survival by the seaside

Increasingly, hominins have survived swings of climate by their wits and by chance. Neither underpin the instinct to migrate when times are hard, but where one ends up depended, until the Holocene, more on chance than design. Early migrations must have been more by diffusion than purposeful, especially in the vastness of the African continent. Yet groups of hominins found their way into Eurasia several times and thrived there. Far more of them would have met the coast far from a continental exit route, such as the Levant or the Straits of Bab el Mandab. However, in stressful glacial episodes reaching the coast was a key to survival as its food resources are almost limitless (see Human migration and sea food May 2000 issue of EPN). Our own species found refuge by the sea not long after we originated (Marean, C.W. 2010. When the sea saved humanity. Scientific American, v. 303 (August 2010), p. 40-47). Around 195 ka climate began to cool and dry to reach a glacial maximum at roughly 123 ka. Curtis Marean (Arizona State University, USA) was one of the first scientists to look for signs of coastal refuges in Africa during the early 1990s, particularly at its southern tip. With co-workers he found several caves on the coast of South Africa that yielded the evidence on which he has based a review of littoral survival opportunities and the skills that we developed. This particular coastal stretch has a huge diversity of plant life, most unique to it, and many of which store carbohydrate in tubers, bulbs and corms. They are adapted to dry conditions and need only the simplest technology – digging sticks and fires for cooking – to exploit starchy, easily digested energy resources, along with the more obvious animal protein sources present on all shorelines. Marean’s review puts in plain language all the discoveries made by his group over the last 20 years, including evidence of the use of fire treatment to improve flaked stone tools and the development of art based on iron-oxide pigments, plus his own take on their anthropological significance.

Another big surprise

The discovery from the Neanderthal genome that people outside Africa have such a muscular bloke in their distant ancestry (see Yes, it seems that they did…in May 2010 issue of EPN) ought to be quite enough of a shock for one year, but hard on its heels comes another. Animal bones from Ethiopia in sediments dated at more than 3.4 Ma show clear signs of having flesh cut from them with a sharp blade (McPherron, S.P. et al. 2010. Evidence for stone-tool assisted consumption of animal tissues before 3.39 million years ago at Dikika, Ethiopia. Nature, v. 466, p. 857-860). The oldest known stone tools date back only 2.4 Ma (none were found at Dikika), and those associated with a known hominin (H. habilis) to half a million years later than that. No species of the genus Homo is known to have been living 3.4 Ma ago, so a likely candidate for making and wielding stone tools then would be Australopithecus afarensis: Lucy’s genus. In fact the infant A. afarensis named Selam (see ‘Peace’ (Selam) disturbed in October 2006 issue of EPN) was found a mere 300 m away from the cut-marked bones.

There are several problems that arise from these butchered bones, as regards their implications. Do hominin specialists reserve the genus Homo exclusively for tool makers? If so, do Lucy and Selam become H. afarensis? But without actual tools associated with the bones, it is impossible to decide whether they were specifically made to deflesh prey or carrion, or were just sharp, naturally occurring bits of stone that some creature with insubstantial teeth happened to use to snaffle a quick snack from competing carnivores. Even more intriguing, in the light of the immense rarity of hominin remains, was there some creature more advanced than A. afarensis roaming the stifling plains of Ethiopia’s Awash valley 1.4 Ma before the first known tool maker? The various Awash projects will run and run after this new and startling discovery.

Neanderthal ‘bling’

Led by João Zilhão of the University of Bristol, UK, a team of British, French, Italian and Spanish archaeologists and anthropologists have at a stroke rid our former companions in Europe, the Neanderthals, of the popular and academic stigma of being uncultured (Zilhao, J. and 16 others 2010. Symbolic use of marine shells and mineral pigments by Iberian Neandertals. Proceedings of the National Academy of Sciences, v. 107 p. 1023-1028). They wore jewellery in the form of necklaces and pendants of bivalve shells, remains of which have turned up in large numbers in caves and rock shelters in the interior of southeast Spain. Some of the perforated shells show clear signs of having been painted, and a few show grooves worn by string. They found even a paint container and painting tools made of small bones from a horse’s foot. The container and tools retain distinct traces of pigment made from the common iron colorants goethite, jarosite and hematite. One large, perforated scallop shell shows that its white interior was painted to match its reddish exterior.

It has often been commented that Neanderthal adornments ( a few possible finds precede this work) and intricate tools were simply copied from those of fully modern humans. The deposits containing this ornamentation are around 50 thousand years old: preceding modern human occupation of the Iberian Peninsula by at least 10 ka. Evidence for artistic work by early H. sapiens comes from South Africa as far back as 165 ka (see Technology, culture and migration in the Middle Palaeolithic of southern Africa in January 2009 EPN, and When and where ‘culture’ began in EPN of November 2007). Iron-based pigments are still widely used for body painting in many societies, but obviously that use will not feature directly in archaeological finds. Association of lumps of potential pigments with hominin tools go back even further in Africa, beyond the presence of fully modern humans, but to ascribe pieces of say hematite to cultural practice needs evidence for scraping or grinding. There seems no reason why Neanderthals and modern humans maintained an ancient cultural tradition.

New Journal

The New Year saw the launch of a new Earth science journal: Nature Geoscience, part of the growing ‘family’ of specialist twiglets from the main trunk of their parent. Whether publishing in it will match the kudos of having a Letter in Nature itself remains to be seen. A monthly rather than a weekly format will keep an issue on the shelf for browsers, but will they rush to thumb through it in paper or on-line? Should Nature Geoscience take off and attract all the geoscience that was once in Nature, then Earth scientists may stop checking through each issue of that august journal, which would be a shame when our discipline is looking for an upsurge in cross-pollination with others. Whatever, the first issue had enough to interest me – three noteworthy Letters – but I can’t say the same for the second.

Watch out, watch out, there are burglars about

f the major journals are anything to go by, the gravest crime that scientists can commit is to make up data and publish the results after peer review. The only thing worse in the eyes of us ‘academics’ is to publish the same makey-up data several times without being rumbled by referees. Once discovered, all the hammers of hell fall on the miscreant: they lose their jobs; their faces are splashed on the news pages of Nature and Science; they are blackballed internationally and can never work in academic circles again. Pretty harsh treatment for what, after all, is a good old-fashioned con (and often one of some ingenuity). In general, most of us love a rascally grifter, so long as they haven’t trousered our life savings. So why is the academic equivalent of the death penalty reserved for what is little different from getting a gullible public to believe that politicians act in the best interests of humanity? If any geologist looked deeply into his or her conscience most would find several cases where they had fudged a bit of data – marked a geological boundary on a map where there was barely a shred of evidence, for instance. We have all speculated well beyond the realms of reality, and often that has passed peer review easily. It is in the very nature of a dominantly observational science to do the odd bit of grifting and have it accepted.

What we detest in real life is the burglar, who desecrates our homes and work. Having anything stolen leaves a life-long trauma and a feeling of being somehow dirtied. In our academic world, theft is called plagiarism. It is most generally applied these days to the actions of students who snip bits and pieces from published sources to get a good mark from a term-paper or dissertation. Like the fabricator of data, they are generally hammered if caught at it. Yet there is a real theft that damages its victims rather than merely soiling the ‘clean image’ of education, and these victims are usually ‘junior partners’ in research. It is rife, and in one form is actually condoned and even encouraged. These days many research students are forced to more or less sign away their intellectual property to their supervisors, often a sizeable posse most of whom do very little, if anything at all. If a research student wants to publish the posse must be in the list of authors. Many commentators have noted that this riding on the backs of the inexperienced is how CVs are built up and fast-track promotion is achieved. It could be called the ‘pillion passenger’ route to greatness. But this kind of institutionalised pillaging is by no means the worst form that plagiarism can take. Far worse is to find out accidentally that one’s original ideas, data, or graphics are being published or uttered by someone else without any acknowledgement, especially if they have yet to be published.

The police rarely catch a burglar, and even less-often recover stolen goods. Similarly, victims of this worst form of academic plagiarism also know that having the record properly set straight is unlikely. The academic burglar excuses him/herself with the defence that, “there is no copyright over ideas”. To accuse such charlatans invites being actioned for libel, because of legal vagueness over intellectual property. Last month I witnessed an attempted burglary at a conference in London. In that case the burglar not only published purloined ideas previously but clearly fed his student those ideas. Unwittingly, she presented them, suitably tarted up, but with him as second author – i.e. trying to have his cake and eat it. All would have gone smoothly for the snaffler, but for one thing. The victim was there and gave the genuine presentation only 30 minutes before the blagged one hit the floor. Quite clearly, she knew what she was talking about whereas the coached presenter obviously did not. Thanks to two or three acute, and honest people in the audience, the game was up. The perpetrator of the burglary was, in the most polite (and legal) fashion, academically savaged with not inconsiderable relish. In a way, justice was done, but not entirely.

Anyone who attempts to build a career by theft needs to be stopped in their tracks, but in the ‘halls of academe’ only con-artists who are caught have the book thrown at them. So, keep your eyes and ears open in 2008, on behalf of others as well as yourself, for that is the only way metaphorically to give burglars a touch of the old Black and Decker about the knee caps.

Assigning Copyright

If anything is growing super-exponentially (where the rate of growth also grows) it is the annual number of scientific publications. Since the number of potential readers is not, a crunch point is surely coming where the average number of readers of a learned paper may be just the authors themselves: someone with the time can do the necessary arithmetic to check that casual prognosis. To a semi-professional browser of a few leading journals in one subject area, it does sometimes seem as if that point arrived a while back. Yet the number of actual journals is growing as well, for example Nature now has more than 30 satellite journals, when once it stood at stratospheric height astride the entire breadth of Science. One journal, which professional etiquette will not allow me to mention by name, is currently submerged beneath a backlog of unpublished but accepted papers, to the extent that a decision to jump from 18 issues to 24 per year has run into difficulties. Its next 6 issues will be bundled into two weighty volumes to clear the desks of a single sub-editor, who it seems is definitely getting a bit ‘frayed around the edges’. How do publishers manage to blurt out such an awesome volume without a sort of heat death of the literary universe and, more mundanely, economic collapse? For a start, they take adverts and up the subscription rates, both for paper and on-line versions. Oddly there is a huge range of subscription rates for top-ranking geoscientific journals, from about £100 for the beautifully typeset and edited Journal of Geology published by University of Chicago Press to almost £3000 for Palaeogeography, Palaeoclimatology, Palaeoecology published by Elsevier (2005 rates). Publishers can charge for colour content – most do but a few do not. Of course, they do not pay for a paper’s creative content, unlike almost every other kind of publication, but that is born of hubris, which is probably inbred among scientists. For the same reason they do not pay their referees; in fact I am sure that some would pay for the privilege (see above). Let us be clear on one thing: scientific publishing is a hugely profitable business, and most scientists would be hamstrung if they did not go along with its rapacity, unless perhaps they club together to create free on-line, peer-reviewed journals outside the pack.

Among the ruses aimed at milking the demonically possessed Gadarene herd, to which most scientists belong, is one worth special approbation: compulsory assignment of copyright (Marris, E. 2006. PS I want all the rights. Nature, v.442, p. 118-119). That is relatively new, and along with it is a rapid attrition of the only perk, free offprints to distribute, amaze your friends and rub salt in the wounds of your enemies. It is now common to give authors only the final on-line PDF, file, but with stern warnings that only a certain number of free distributions are allowed. To get paper offprints (still much more highly valued by colleagues than electronic text), authors increasingly have to pay extortionate fees, almost equivalent page per page to the market value of a hand-illuminated, mediaeval manuscript. Let’s get this straight, publishers do not pay authors (and referees), and often demand payment for necessary colour work that visually enhances journals (costs of 4-colour printing have plummeted in recent years), yet claim ownership of the published article, effectively violating the intellectual property rights of authors. A powerful move against this is beginning. Original PDFs of almost 50 % of papers inScience and Nature and increasing numbers of those in other prestigious journals are appearing for free download from the Web. Major grant givers in the medical sciences now demand that work that they sponsor becomes free to all, once published. Some provide authors with forms to add to the copyright transfer papers that must be signed to ensure free access to all. Publishers complain direly that such action will destroy their journals financially, claiming that, ‘the final version is where publishers add value’ and that the version published by a journal is ‘definitive’, ‘part of the minutes of science’. Readers can draw their own conclusions about this issue of form versus content. It is relatively simple to prepare PDFs of corrected papers and their figures to a publishing standard and distribute them freely, a widely adopted move among physicists, biologists and medical scientists through open-access libraries such as PubMedCentral.


Anonymous referees

Anyone who submits their first paper to a journal soon becomes aware of the “peer review” process: probably the single greatest contributor to academic suspicion and anxiety.  Of course, these “peers” fall into two categories: the “esteemed colleague” (helpful); the “witless wonder” (negative, and prone to crushing your paper).  Write a book, a play or an operatic score, and your critics in the media have a name.  You could even find out where they keep their pet rabbit.  They are accountable. Yet, editors of journals claim to have a “duty of confidentiality” towards those referees who opt for anonymity: guess which category most often does. At one time or another, most academics asked for critiques by learned journals only to recommend rejection have succumbed to “taking the veil”.  Equally, there are few researchers who have not suffered a similar fate to one they may have meted out themselves.  Learning by experience is not necessarily a strong point among scientists.  A typical case came to my notice recently, but the identity of one faceless and repugnant referee eventually became clear.  I know him well.  He too had suffered acute stress from a grossly delayed manuscript and the vicious comment of an anonymous referee some years back, yet saw fit to indulge his own spleen when offered a place in the shade: goodness only knows why, but in this case I have my suspicions.

The whole scientific community grows increasingly uneasy about anonymous peer-review, and the abuse that it sometimes makes possible. Examples are deliberate delays by unnamed referees engaged in similar research or related commercial activity, plagiarism, incompetence and the self-indulgence of gratuitously destructive and belittling comment.  It is the near-universal policy of referee anonymity that allows these unwholesome practices to fester and grow.  Most journals give their referees the option of coming out of the closet, or remaining smugly behind its door.  Some assume anonymity, so that a referee has to ask explicitly for their name to be revealed.  Anonymous referees are simply moral cowards, along with editors of the journals that give them a cloak. What do they fear?  Are direct questions about their comments cause for timidity?

Referee malpractice can be removed completely by editors refusing to allow referees to skulk behind anonymity. Now, in the UK at least, it seems possible to challenge this unwholesome editorial prerogative, because of the Freedom of Information Act 2000 (2002 Scotland), which came into force on 1 Jan 2005, and the Data Protection Act 1998.  Resorting to the Acts ought not to be necessary as regards the activities of scholarly journals, yet editors continue to defend the more faceless of their referees.  No doubt there would be a temporary shortage of referees should compulsory “outing” become the norm, but it would remove those who do engage in malpractice.  The most important result would be an increase in objectively constructive comment, which softens the blow of a rejection slip by showing a way forward to authors.   Peer-review should work both ways, and should be seen to be honest.


Protecting your intellectual property

Long ago, most students entered research by thinking up their own project, albeit with advice from potential supervisors.  That is rarely possible today, for many reasons.  Instead, gifted students are recruited to research topics proposed to funding agencies by established scientists.  More often than not, such projects slot into an overall strategy centred on an academic’s career or the ambitions of a research group.  There are advantages in having the sometimes undivided attention of a “boss”, a structured approach to work within a broader framework, access to a group’s equipment and funding, and support from several co-thinkers.  With the old style, there were risks in “ploughing a lone furrow”, such as abandonment by a disenchanted supervisor (the enchanted ones could be even more worrying).  The single most important advantage of designing your own project, hard and risky as that might be, was one of possession from the outset.  Such responsibility develops qualities that are otherwise not easy to get: independence of thought and action, time-management,  resourcefulness, an ability to argue your case, and self-discipline – if you can really “hack” it.  Except for the indolent and irrecoverably stupid, most people can, given some knowledge of where their subject is going and thesine qua non of curiosity.  In those “old days”, the risks were more than offset by the advantage of ownership, and it was rare for postgraduates not to be successful, and the majority gained their doctorates within three years.  Today, up to a third of enrolled graduate students withdraw or fail their degrees, and hardly any complete inside this reasonable period.

Funding agencies now demand guarantees that their outlay bears fruit.  They increasingly direct lines of research, so that studentships follow previous funding.  The funders are more accountable, and by the iron logic of the marketplace so too must be the recipients.  The upshot is continual assessment of research performance by departments, the creation of “centres of excellence”, and the crushing of departments that do not measure up to an amoebic growth of criteria and guidelines.  So, for anyone keen on testing their abilities to the limit and following their curiosity, the options are increasingly limited.  Even if you have independent means, it is now a very rare department that encourages self-motivated research by students, or even by its established staff.  In truth, most academics find it hard to be independent, because they no longer have the security that once guaranteed freedom of thought, action and expression.  In Britain, if an academic began their career or earned promotion after 20 November 1987, they can be dismissed solely on grounds of redundancy, rather than “with good cause”, which was the rock on which tenure used to be based.  “Gross moral turpitude” was, I believe, the operative and infinitely more expressive phrase in US institutions.  So for your average supervisor the world has turned upside down.  Now it’s a case of “publish or perish”, larded with citation and impact records, and bringing cash into your institution to boost its research assessment.  There are very few academics with the energy, imagination, brass neck and wit to jump through all these hoops and remain sanely independent.  So we see a growth of hidden but nonetheless unwholesome vices adopted by some to survive and prosper in this deranged environment.  There are many victims, but the new researcher is most at risk.  During the festive season it is customary to give and receive advice, as well as greetings.  Here is some that concerns the vice that dare not speak its name –plagiarism – in the form of a bestiary to help you memorise potentially risky people.

  1. Chameleons Check out potential supervisors.  The Science Citation Index will reveal their record of sole or senior authorship of papers (notreviews).  If they are what they claim to be, that will dominate.  Relative to that, how many times does their name appear within multi-author papers, of which they are not senior author?  If the latter dominates, their reputation probably rests on offering technical facilities that they control, or the research talents of other people.  You may find individuals who have a short publication list of either kind.  They are either at the start of their career, or beyond all human help (except perhaps your own).
  2. Beavers Never let anyone else do any work for you, unless they are a kindly technician (who then deserves at least an acknowledgement).  Where possible, keep your research materials under your personal control – in some institutions burial is a useful tactic.
  3. Curlews Be suspicious of a supervisor who shares your findings with the rest of a team; either you do that yourself or not at all.
  4. Moles Although communication with others is an essential aspect of research, until you are ready to submit a paper for peer review, do not reveal all in seminars and conferences.  Pay particular attention to your posters.  At every conference you will see people photographing them, whom you can safely assume are after your ideas.
  5. Hamsters Beware the friendly soul offering, without being asked, to read your first draft of a paper.  Instead, plead with the most curmudgeonly academic around, the one who hammers your every utterance, for he or she will probably be honest.
  6. Tapeworms Do not allow your supervisor to routinely add their name or others in a research team to your papers.  Authorship is not based on advice, basic training in research techniques or discussion of your work.  That is your supervisor’s duty of care, and a good one should give far more than they take. Acknowledgements are the place to express gratitude for such assistance.  Authors have to do real work, both analytical and intellectual, to deserve a place in the list.
  7. Squirrels Insist that your supervisor lets you read all drafts of their papers that bear on your own field, to check that your findings are not included, as well as to learn.  If your work appears, you have a right to authorship.
  8. Weasels Be aware of the relationships among academics and post-docs in your department, and theirs with others in outside institutions.  Keep an eye on “networking”, which often involves mutual sharing of information as well as gossip, particularly if joint bids for funding are in the offing.
  9. Ravens It is easy to be pressured overtly and subtly, particularly in a large research group.  That may be beneficial, but can be to get you to toe the “party line”.

10.  Wolverines Never tolerate anything that seems like plagiarism, manipulation, obstruction, exploitation, bullying or harassment.   Best to confront politely yet firmly the person responsible, but that is not easy.  Finding someone who can help is not easy either.  Your institution may well have a policy of pastoral care based on designated individuals, who are deemed to be disinterested and trustworthy.  In the real world there is a culture of protecting long-term colleagues, which extends throughout a university; you are transitory…  In case of difficulty, ask to change your pastoral advisor.  Other students of longer standing may know who is straight, or have similar experiences.  Whatever, it is essential that you get honest support to resolve such problems.  One useful tactic is to air your grievances as accurately as possible in writing, with a copy to someone that you can trust.

11.  Diverse enchanted beasts The most difficult obstacle to ownership can be, oddly, the genuinely honest, kindly and enthusiastic supervisor.  Because of their greater experience and breadth of knowledge, your work can easily become their obsession, usually because of their frustration with your progress.  They will not steal your thunder consciously, but can easily end up driving you rather than the other way round.  If you want to become their creature, fine.  If not, then you have battles ahead, but they will serve both of you well!