The weekend
Tired and unfocused after last night’s fun, I stumbled a lot around the dark red oil shale rocks in our next site. I did not quite catch where we were exactly, because it was not according to schedule. Actually, none of the sites we visited this day were planned, but the localities we had intended to go to first were closed, or unavailable for other reasons I cannot recall. Not that that was bad in any way, it’s just that I did not know where we were. (If anyone who knows me well would describe me in three words, I am sure two of them will be “generally disoriented”.) Our guide mentioned Kukersite, which sounds like a site, so I thought that was the name of this place, but I checked it up, and kukersite is actually a type of Estonian Ordovician marine oil shale – kukersite is the type of rock, not the name of the locality.
This, our guide said, was an incredibly diverse fauna, with over 200 identified species! The environment would have been a very rich marine environment, which is unusual for oil shales. This rock type has a high content of organic matter, and therefore usually forms in anoxic conditions, where the decomposing microbes do not have enough oxygen to break down the dead organic matter, which instead is preserved in the rock, if buried by sediment. This habitat, however, was clearly teeming with life, and would thus have been full of oxygen (otherwise, so many animals could not have lived there), which attributes the high amount of organic matter in the shale to the fact that there actually was so much life there that the sediments that later buried the environment would have been full of organic material.
The brachiopods of this locality were wonderfully well-preserved, three-dimensionally with shell and all. I found a complete rhynconelliform (I think), slightly larger than a thumb nail, beautifully preserved with clear shell details, but it somehow got lost on the way back to the bus, possibly because I put it in the same pocket as I had my gloves; it might have fallen out as I took the gloves to put on my cold hands. A terrible mistake I hope will be the first and last of the sort! I was quite demoralised after that.
There are also few pictures from this locality, as I was “busy” searching for trilobites. I had already found an impressive brachiopod, and I did not expect that I would eventually lose it, so I went after a second trilobite find. Stephen picked up trilobite after trilobite, so you can imagine how jealous I was when I could not find anything except a weird mark that looked like one, with a little imagination and a great deal of wishful thinking.
Although I did find something for the first time in this trip: an orthocone, a type of straight-shelled cephalopod, related to squids and octopi (plural of octopus; things ending with -us get their end changed into -i in their plural form, e.g. cactus, fungus, mucus). (Note: that last example was a joke, in case you did not realise; mucus does not even have a plural form.) The orthocone preservation is rather remarkable. Usually, as for example typically seen in old marble stone floors, the shell structure is what is preserved, where you also can see the inward-curved walls (septa) dividing the shell into several small chambers. In this specimen, however, the shell has vanished, and the chambers are preserved instead. The shell minerals have probably been dissolved away, leaving only the already solidified sediments that filled the chambers.
The last picture I include mostly to show the importance of having a scale in the picture.
These trace fossils look enormous, mostly because the people in the background seem small. Really, they are just standing far away – more than ten metres – but it is hard to tell since you cannot see the ground. I am also standing quite close to the fossil block with my camera, but it is impossible to tell how near I stand. I only have a rough idea of the diameter of the burrows, but I will leave it untold, and let you guess instead. It’s more frustrating that way.
The final fossil site we went to was another cliff exposure with early Ordovician limestones near a small stream.
The exposure was barely broad enough for all of us to look at it at the same time, and the area between the cliff and the stream was a narrow, steep heap of rock fragments. Therefore, our teachers were kind enough to skip any detailed examining of the cliff layer sequence. They definitely knew all about it and certainly had a lot to say, but decided to be merciful and let us roam for fossils instead.
It was quite hard to find anything. I had probably been looking around for ten minutes without seeing a single fossil before I began to give up hope. But, the persevere prevail – I picked up a rock, turned it over, and there it was: a tiny but oh so clear trilobite!
Trilobites are called so because their bodies are divided into three lobes: the axial lobe, running centrally from head to hindpart, and two pleural lobes on the sides of the axial one. Now, you probably wonder what a lobe is, and, honestly, I am not quite sure. The Concise Oxford Dictionary (seventh edition) defines a lobe as a “roundish and flattish projecting or pendulous part, often one of two or more such parts divided by a fissure”. The former part seems to be more applicable to the earlobe, and the latter seems to be a rather vague description. This confusion is not made easier by the fact that trilobites are also clearly dividable into three parts across their length too: the cephalon (head), thorax (main body, containing the legs etc.) and pygidium (hind part, almost like a short tail). Since it is quite unclear what a lobe is, it is easy to think that the tripartite division is between these parts. (A word of warning: this opens up a possibility for a trick question on any trilobite-related exam, so make sure you remember that the lobes run along the length axis.)
Curiously, the fossil I picked up had only the pleural lobes preserved – the centre was missing, and so was the head and maybe the tail. Since the head part is gone, it might be impossible to tell how large this trilobite actually was, since the thoracic segments vary greatly between different species. In other words, we cannot tell how much of the animal had been cut off – is this just the tip of the hindpart, or is it most of the body?
Regardless, it is the prettiest trilobite I could ever dream of finding. I do not dare to try to break off the rock around it, although it is so soft it could easily be done by fingers. The risk of breaking this peculiar fossil is too great, since you never really know how a rock will break apart – it could just as well turn the trilobite into powder.
I had found a second trilobite, and not a weird thingy like at Ohesaare, but a clear specimen that even I myself could tell was definitely a trilobite! It would not win Graham’s competition, but it would certainly win my own.
Unless…
There, just lying there, completely exposed among the fragmented rocks and dirt, it was: another trilobite, so amazing that I could not believe it!
It was big, roughly the size of a thumbnail, and exquisitely preserved – although lacking the head. Here, you can clearly see the three lobes, and how they can be distinguished all the way down through the pygidium. It even looks as if the outer shell of the pygidium has been pealed off, revealing the internal structure of the tail part, but I do not dare claim anything for certain.
I feel false pride about having found this weird and truly wonderful trilobite, but it was really mere luck. It was so exposed that anyone who would have gazed upon it would have noticed what it was. My eyes just happened to look at the right place.
Still, that does not stop me being incredibly happy about it! And I could go on about how terrific this discovery was to me, how beautiful it is, and what a treasure it is for a beginner like me, but I will leave it at saying that it made it among the three winners of Graham’s trilobite tournament! I was guaranteed a lovely apple juice on the boat.
This was truly the climax of the trip, in terms of fossils, and conveniently at the last site. From here, we returned to Tallin to catch the ferry back home.
The last night was truly a night to celebrate, not only because it was the last night, but also because the following day was Heda’s birthday!
Not being a fan of alcohol, I restricted the celebration beverages to a sip of champagne and a try of port wine. When I chose my trilobite award drink to be a glass of apple juice, Stephen sighed and said that I failed the first test to becoming a paleontologist – drinking hard. Oh, well…
The ferry had the good taste of having a lot of Latin American music, which I realised is the only type of music I can manage to dance fairly well to. I think it is because the rhythm is weird enough – I cannot move to those regular pop beats… they are too normal.
A few years ago, the stench of cigarette smoke was utterly unbearable to me, but I have gotten more used to it, which is lucky, as the place where most people went to chat and get some fresh air was the smoking room. The fresh air bit might seem ironical (and it is), but the reason is that the smoking rooms were basically outside, with only a roof on our heads, the wind naturally blowing away the smoke. So, this was the place for conversation, which is my favourite part of socialising.
Illiam had earlier gone on about knowing the world’s most gruesomely brilliant limerick (a type of five-lined poem with a certain rhyme pattern – aabba – and usually a perverse twist in the end), but would not tell it, no matter how much we pleaded him. Finally, he said that he would tell it to anyone who was up after 3 am. Naturally, I had to stay up that long, but I could not find Illiam after that, so I never got to hear it anyway. For better or for worse?
Although it felt sad to leave my new friends in the morning, I knew I would see them again sometime, and I was longing to come home. It had been a truly fantastic adventure, but it was enough for now. All I wanted was to rest, and remember the taste of my mom’s wonderful food.
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