One field day in a paleontologist’s career

By ōu zhì jí

A typical day on Digermulen starts with a cheerful breakfast in our kitchen tent — bacon, fried eggs, porridge and müsli, usually accompanied by tea, coffee or hot chocolate depending on what we feel like. Such high-calorie food guarantees enough energy for a sturdy hike in the morning and a long workday. After breakfast, researchers will discuss the day’s destinations; bad weather can have a large impact on planned work. We then grab something for our individual packs as lunch — including bread, dry tech, cup noodles, fruits, norwegian sausages, hot water and any leftovers from breakfast. We do this because the field localities are not always near our campsite, we do not want to spend lots of time hiking back for lunch.

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Figure 1. Organisms living on Digermulen besides visiting paleontologists. A: a stranded comb jelly awaiting photography. B: a lonely reindeer await his true love. C: a vivid sea urchin. D: edible mushrooms picked by Wendy.

Besides the basic necessaries for surviving a day in the field, we also need to pack our ‘working tools’. A geologist’s hammer is the most important tool, which is used in several ways, such as obtaining a fresh surface of a rock to determine its composition or reveal fossils inside, splitting fine-grained clastic rocks to search for macrofossils, breaking rocks to make them smaller for transport back to campsite, they can also be used as a scale for photography. Chisels, crowbars and sledgehammers are useful aids to the hammer. We use a high-resolution geological map, topographic maps and GPS when we get confused about the layers of rock, when we try to find an easy path to our destination, or simply record where we are in the notebook. Any interesting observations or ideas during fieldwork is written down in the notebook and we go through our notes every evening in camp. A good camera is a powerful tool to rescue paleontologists from field sketching as they did 50 years ago, especially for those who are not good at drawing. Photographing is faster and record more details than the old fashion, however, the simple sketches in your notebook are invaluable. Sampling bags and newspapers are used for packing samples. Sometimes we bring the equipment needed for casting as well — not all of the valuable specimens are possible to collect, and some are simply best left in place.

Then we head out on foot rather than four-wheelers — the only roads are reindeer trails. However, we travel by boat occasionally when the sections are all along the seashore. In the field, we observe rocks, write down what interests us scientifically and collect, or make casts of what we cannot bring back. There is a short break at noon for lunch. Moreover, we can have numerous breaks for watching whales, seals, reindeer, birds or just scenery — as long as there are no other paleontologists around!

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Figure 2. Splendid scenery on the Digermulen Peninsula. A: a quartzite castle of the Great Digermulen Empire. B: a reindeer trail leads you to heaven. C: multicolored beach made by colorful sandstones. D: a sunny day for fossil hunting. E: view over to the Varanger side. F: trilobite hunting ground.

The end of the day is to share a long dinner in the kitchen tent together. Different from the lunch, the dinner is always cooked in pots and pans (many thanks to the chefs). But, refilling empty stomachs is not the only theme: researchers take out exciting fossils collected on that day and have heated discussions. After that, a summary of the day gone by and a simple plan for the next day are discussed.

Around 10-11pm, everyone goes into his or her own tent to recover from the day’s hard work and look forward to the next expedition on the coming day. Nevertheless, I think the best way of relaxing is to loose myself in the most beautiful scenery ever to exist on our lovely planet.

1000 thanks to the organizer and everyone in the field this summer!

Scientific super powers!

By Wendy L.Taylor

All scientists use one tool more than any other in their academic arsenal – the power of observation. A keen sense of observation is the foundation of rigorous science and the key to unlocking new discoveries. In the world of field-based research, what we observe – often in the most physically challenging and uncomfortable of settings – fuels our curiosity and inspires our most basic urge to explore the world. Ionian philosophers, Anaximander and Xenophanes, of ancient Greece made some of the earliest geological observations during the 6th Century B.C.E. They noticed the presence of fossil fish and shells in rock far removed from oceans of the day and suggested they were once living animals buried in mud during ancient floods. Observations like these, paved the way for the birth of paleontology, the study of the history of life. As a modern day paleontologist, I have access to an array of powerful technologies designed to enhance and sharpen my powers of observation in the field and lab. Some new and some not-so-new tools including photogrammetry and panoramic photography, X-ray imaging and even robotic technologies make it possible to capture important scientific details and share discoveries with the public in new and exciting ways. Here are some examples from our recent expedition to study the extraordinary fossils of the Digermulen Peninsula in northern Finnmark.


Figure 1: Flying of “Major Tom” (inset) in the field at Digermulen (left). A drone’s view of the Lower to Middle Cambrian age rocks (~540-520 million years) of Breidvika Valley.

First used on a large scale by the military for combat purposes, growth in the use of UAV’s (unmanned aerial vehicles) or drones has dramatically expanded over the past 10 years due to the miniaturization of scientific instrumentation and the accessibility of affordable models. Today there is widespread deployment of drones in the biological, geological and atmospheric sciences. Images and video taken by our project’s drone, affectionately named “Major Tom”, at Digermulen give a bird’s-eye view of important rock outcrops (Fig. 1) that record approximately 200 million years of Earth history during a critical time in evolution of complex life. These rocks contain the oldest evidence of multicellular animal life in Scandinavia!

Another tool we use to image rock surfaces in the field is panoramic photography. This technique is done with a camera mounted on a specialized panoramic tripod head that allows 360° rotation on a tripod (Fig. 2). A series of images are taken at 30° increments and stitched together using specialized software.

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Figure 2: Spherical panorama set up (right) and me photographing at Digermulen (left). 360° panorama movie made of one study site at Manndrapselva.

The resultant 360° interactive movies or “sphericals” can be hosted on websites and offer an immersive view of remote field sites (Fig. 2). Examples of spherical panoramas used for geoscience education can be found online at http://vft.asu.edu. We also capture high-resolution gigapixel panoramas that are made of 100’s to over 1000 images stitched together. These images give researchers the chance to study the details of large areas that are difficult to access in the field and can also be used in a variety of educational contexts.

For the study of much smaller features such as the delicate morphology (form and structure) of fossils and their state of preservation in the rock (or taphonomy), we use macro photography (see Fig. 3). This type of photography is done using a camera with a macro or close-up lens mounted on a tripod (or copystand) with lights. Many fossils require extra preparation before they can be photographed. The first step involves the cleaning and removal of any extra rock covering the fossil (mechanical preparation), 2) blackening with water-based ink to reduce the effect of colors on the surface, and then 3) whitening with ammonium chloride to bring out fine details. Whitening is done with a glass tube filled with ammonium chloride powder that is heated over a flame (Fig. 2). When heated the powder forms a gas that sublimates when it cools to form a white coating on the rock. This enhances fine surface details and often brings out features the eye cannot discern. Now the fossil is ready to be photographed.

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Figure 3: Fossil specimen being blackened with ink (left), whitened with ammonium chloride in a fume hood (bottom) and then photographed.

These modern tools enhance our limited human capabilities allowing us to make many more observations much more precisely. We need all the help we can get to extract the elusive clues of how organisms lived and died in ancient oceans over 540 million years ago!

Tracing the early evolution of animals on Digermulen Peninsula

by Sören Jensen

For most of the Earth’s history life consisted of small, mainly single-celled, organisms. It is only in rocks deposited during the last 570 million years before the present that large, complex, fossils appear, indicating the rise of animals. Digermulen Peninsula, northern Norway, offers the opportunity to study rocks, the Stáhpogieddi and Breidvika formations, laid down during the time of early evolution of animals. The interpretation of the best known of the earliest large complex fossils, the so called Ediacara-type fossils, also found on the Digermulen Peninsula, is controversial; some may bear no relationship to now living animals, some may be related to cnidarians, with there being few candidates for bilaterian animals such as worms or arthropods. Some of the earliest evidence for bilaterians, in fact, comes from burrows and other activity left on, and inside, the sea-floor. Although little can be said about the producers in detail, the complexity of the traces suggest they were made by an organism with features characterizing bilaterian animals. This includes an anterior concentration of the nervous system and an internal body cavity. So, by the beginning of the Cambrian Period, some 542 million years ago, complex branching burrows are found, some of which are called Treptichnus pedum (see image). The argument can be extended to even earlier and more simple trace fossils (see image), on a global scale indicating that bilaterian animals were around at least as far back as 555 million years before the present.

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Trace fossils from the Digermulen Peninsula. To the left, Treptichnus pedum, from the basal Cambrian part of the succession; to the right, simple trace fossils from late Ediacaran rocks. Photo Sören Jensen, scale is 2 cm for both images.

After the appearance of complex branching trace fossils, the next major innovation, about 535 million years ago, was the appearance of trace fossil showing evidence for limbs such as those on modern arthropods. This order of appearance of trace fossils has been documented globally, and the first appearance of complex trace fossils such as Treptichnus pedum has been choosen to mark the beginning of the Cambrian Period of time; on the Digermulen Peninsula, placing the Ediacaran-Cambrian boundary in the upper part of the Stahpogiedde Formation. Rusophycus, a burrow made by arthropods, occurs slightly higher in the succession, in the Breidvika Formation. Ediacara-type fossils are known from lower and middle part of the Stáhpogieddi Formation. No trace fossils have been found in these beds, suggesting either an age older than about 555 Ma for these fossils, or that the activity did not get preserved. This is one of the questions that we are currently exploring.

Forsteinet oppførsel

Av Magne Høyberget

Det å finne fossiler etter urtidsdyr er selvfølgelig svært spennenede og interessant i seg selv, men vi finner også en annen slags type fossiler her på Digermulen: Vi finner noe så utrolig som forsteinet oppførsel etter disse dyrene. En lang rekke forskjellige organismer som trilobitter og andre leddyr, marklignende vesener og bløtdyr har beveget seg gjennom mudderet på en havbunn som er eldre enn en halv millard år gammel og etterlatt seg spor! Noen steder er det så tett med sporfossiler at de nærmest dekker lagflaten.

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Fig. 1: Store gravespor ligger så tett at de overlapper hverandre (Foto Magne Høyberget).

Det fantes et mylder av vesener som ikke hadde noe hardt skall og som dermed ikke kunne bli forsteinet. Takket være sporfossilene så ser vi at det har vært et slikt yrende liv på urtidshavbunnen.
De forskjellige organismene har etterlatt seg sine helt spesielle og gjenkjennelige spor. Noen gravde seg loddrett ned, andre ploget og snodde seg fram, mens atter andre gikk i spiral eller lagde seg forgrenete graveganger i mudderet. Disse sporene og gravegangene i mudderet ble siden fylt igjen med litt grovere sand. Gjennom millioner av år er både mudder og sand forsteinet. Sandinnfyllingene er motstandsdyktige mot erosjon, mens den bløtere mudderforsteiningen har løst seg opp og dermed står flotte avstøpninger igjen etter sporet. Rett og slett en forsteinet oppførsel!
Disse sporfossilene blir gitt navn etter hvordan de er blitt lagd. Dette betyr at forskjellige arter kan ha beveget seg på samme måte og dermed lagd samme type spor.

Slike sporfossiler er nyttige. Noen dyr gjorde helt karakteristiske bevegelser og flere av disse lett gjenkjennelige sporene er funnet over store deler av verden. Noen lagrekker har sine helt typiske sporfossiler, dermed kan vi sammenligne med andre steder i verden og si noe om alderen på de lagrekkene vi undersøker.
Vi har til og med lett etter helt spesielle typer spor som vi forventet å finne i bestemte lagrekker, fordi de burde opptre på samme tid på Digermulen som andre steder i verden –og funnet dem!
Vi finner også nye typer spor som viser en oppførsel som ikke er beskrevet tidligere. Disse kan vi beskrive og gi nye navn.

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Fig. 2: Her er det sannsynligvis den samme trilobitten som har gravd ned i mudderet og etterlatt seg krafsespor. Denne type krafsespor kalles Rusophychus. (Foto Magne Høyberget)

Trilobittene har etterlatt seg mange forskjellige slags spor etter forskjellig slags oppførsel. Dette kan være både hvilespor, gang- og løpespor eller spor etter jakt. Alle disse sporene har dermed fått forskjellige navn. Det kan til og med se ut som om vi finner spor etter dramaet der trilobitten har krafset seg gjennom mudderet langsetter et markspor og fanget marken. Gravesporet etter marken ender brått i trilobittens krafsespor.
Dermed forteller sporene oss noe om hvordan de forskjellige dyrene faktisk levde i kambriumperioden, for en halv milliard år siden.

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Fig. 3: Her har en trilobitt ploget seg gjennom mudderet og etterlatt seg et langt spor med avtrykk etter beinparene. Denne type spor kalles Cruziana. (Foto Magne Høyberget)

Biostratigrafisk överblick utav utbredningen av Sabellidites – en loggblogg

Av Frida Hybertsen

Att åka ut i fält inger alltid en särskild känsla av upprymdhet och speciellt nu när jag får chansen att vara en del i en riktig forskningsexpedition. Vid fossilletande i en lagerföljd är det viktigt att kunna korrelera sina fynd till en viss nivå i lagerföljden så att det är lättare att jämföra med samma lagerföljd på en annan plats. På så vis kan en överblick utav utbredningen av ett specifikt fossil ges på olika ställen och det blir lättare att återskapa t ex levnadsförhållandena som de var eller preservationen av fossilet. Min del i det här projektet är att skapa en logg över den tredje cykeln i Manndrapselva member, Finnmark i vilken utbredningen av fossilet Sabellidites är beskriven. Det kanske inte låter som en alltför svår uppgift, men att skapa en tillräckligt detaljerad logg över nya sediment som jag bara sett på karta tidigare när jag dessutom bara tränat loggning på sektioner några få meter höga och under mycket kortare tid så blir det här en ganska knepig uppgift. Som student har jag inte riktigt hunnit upprätta en vana för loggning, vilket hade gjort uppdraget mycket lättare.

När jag först fick se sektionen som skulle loggas tyckte jag att det såg bra ut, lagrena var väl exponerade och såg ut att vara lätta att följa. Jag fick hjälp med att etablera en startpunkt, min nollpunkt i loggen. Nollpunkten sattes strax under ett finkornigt lager innehållandes massiva sandstenlinser – distinkt och lätt att komma tillbaka till. Därefter började jag beskriva lagrena.

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Figur 1: Lagerföljden mellan 0-6 m i loggen. Foto: Bianca Harrison.

Manndrapselva mbr är ca 60 meter tjock och lagrena har beskrivits tidigare, men inte just här. Jag fick därför rådet att logga en meter i taget för att få tillräckligt många detaljer i loggen. Efter att ha loggat ca tre meter på en halvtimme insåg jag att min logg förmodligen är alldeles för detaljerad. Ett nybörjarmisstag. Då jag tog ett steg tillbaka och tittade på hur lagerföljden såg ut ovanför och under den meter jag loggade insåg jag att lagrena var väldigt uniforma och att jag då hellre kunde logga upp till tre meter istället för en meter just här. På så vis loggar jag en yta som är i stort sett likadan i ett längre spann och kan då markera större förändringar eller speciella strukturer här som en notis vid sidan om loggen. Då blir loggen mindre plottrig och lättare att överblicka. Så istället för att stirra mig blind på varje liten centimeter kunde jag nu skissa på en mer generell logg och så fort jag hade lärt mig ungefär hur detaljerad loggen skulle bli gick det lättare och snabbare att logga resten av sektionen. För att hålla koll på var i loggen jag befann mig vid fick jag hjälp att sätta ut nivåmarkeringar så att jag lätt kunde se hur högt upp i lagerföljden jag befann mig.

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Figur 2: Nivåmarkering 25,5 m. Nästan halvvägs! Foto: Frida Hybertsen

Eftersom fokus i min uppgift ligger på att visa utbredningen av ett specifikt fossil i en lagerföljd behöver loggen inte innehålla centimetervisa detaljer, men eventuella strukturer i lagrena såsom rippelytor, strykning och stupning, erosionsytor etc. är inkluderade för att ge en så klar bild som möjligt. För att visa utbredningen av Sabellidites loggar jag provtagningplatser markerade av mina projektkollegor. Där någon av dem hittat ett fossil placerade de ett gult band så att jag senare kunde gå och samla in samt numrera alla prover. Numreringarna fördes sedan in i loggen som en notis vid den nivå som fyndet gjorts.
Jag loggade hela sektionen under två dagar, den första skissen var nästan färdig under dag ett. Det gick extra fort eftersom jag hela tiden hade hjälp utav en annan masterstudent, Bianca. Under dag två var jag tillbaka i sektionen för att färdigställa loggen. Då fick jag även input från flera håll angående eventuella ändringar och generell feedback, mycket uppskattat!

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Figur 3: Förslag till ändringar och generell feedback innan loggningen under dag två. Foto: Wendy L. Taylor.

Men efter det ville jag helst göra om hela loggen eftersom jag tyckte att den hade för många brister. Efter lite eftertanke insåg jag dock att alla detaljer faktiskt finns i mina anteckningar, om än lite ostrukturerat. Jag får kanske rita om loggen både en och två gånger, men all information är samlad och mitt fältuppdrag är avklarat.