Maria Matilda Ogilvie Gordon - A Women Geoscientist In The Dolomites

The Scottish Maria Matilda Ogilvie Gordon (1864-1939), or May as she was called, was the oldest daughter of a pastoral family composed of eight children, five boys and three girls. Maria Ogilvie entered Merchant Company Schools' Ladies College in Edinburgh at the age of nine. Already in these early years, she showed a profound interest in nature. During holidays she enjoyed exploring the landscape of the Scottish Highlands accompanied by her elder brother, the later geologist Sir Francis Ogilvie. Maria Ogilvie aspired to become a musician and at age of eighteen she went to London to study music, becoming a promising pianist, but already in the first year her interests into the natural world prevailed and she went for a career in science.

Studying both in London and Edinburgh she obtained her degree in geology, botany and zoology in 1890. Maria Ogilvie hoped to follow-up their studies in Germany, but in 1891, despite a recommendation even by the famous geologist Baron Ferdinand Freiherr von Richthofen (pioneer geologist of the Dolomites), she was rejected at the University of Berlin - women were still not permitted to enroll for higher education in England and Germany. She went to Munich, where she was welcomed friendly by eminent paleontologist Karl von Zittel (1839-1904) and zoologist Richard von Hertwig (1850-1927). However, she was not allowed to join male students. Sitting in a separate room she listened through the half-open doors to the lectures.

In July 1891, Richthofen invited her to join a five-week trip to the nearby Dolomites Mountains, visiting the Gröden-Valley. From the very first day, Maria Ogilvie was immensely impressed by the landscape and learned rock climbing to better explore the mountains. Richthofen introduced Maria Ogilvie to alpine geology and they visited the pastures of Stuores in the Gader-Valley. At the time Maria Ogilvie was studying modern corals to become a zoologist, but Richthofen, showing her the beautifully preserved fossil corals found here in the Triassic sediments, convinced her to become rather a geologist.

The pastures of Stuores in the Gader-Valley with outcrops of Triassic marl.

Richthofen was over sixty years old and therefore he couldn't provide much support in the field. Maria Ogilvie remembers later the challenge and danger of field work, sometimes accompanied by a local rock climber named Josef Kostner:

"When I began my fieldwork, I was not under the eye of any Professor. There was no one to include me in his official round of visits among the young geologists in the field, and to subject my maps and sections to tough criticism on the ground. The lack of supervision at the outset was undoubtedly a serious handicap."

For two summers she hiked, climbed and studied various areas in the Dolomites and instructed local collectors to carefully record and describe their fossil sites. In 1893 she published "Contributions to the geology of the Wengen and St. Cassian Strata in southern Tyrol". In the paper she included detailed figures of the landscape, geological maps and stratigraphic charts of the Dolomites, establishing fossil marker horizons and describing the ecology of various fossil corals associations. She described 345 species from the today 1,400 known species of mollusks and corals of the local Wengen- and St. Cassian-Formations.
The published paper, a summary of her thesis "The geology of the Wengen and Saint Cassian Strata in southern Tyrol", finally earned her respect by the scientific community. In 1893 she became the first female doctor of science in the United Kingdom. The same year she returned into the Dolomites to continue with her geological and paleontological research. In 1894 she published the important "Coral in the Dolomites of South Tyrol." Maria Ogilvie argued that the systematic classification of corals must be based on microscopic examination and characteristics, not as usually done at the time, on superficial similarities.

Fossil corals from the pastures of Stuores, plate from LAUBE (1865).

In 1895 she returned to Aberdeen, where she married a longstanding admirer. Dr. John Gordon respected and encouraged her passion for the Dolomites. He and their four children accompanied Maria Ogilvie on various excursions into the Dolomites.

In 1900 she returned to Munich, becoming the first woman to obtain a Ph.D. She helped her old mentor, paleontologist von Zittel, to translate his extensive German research on the "Geschichte der Geologie und Palaeontologie" - "The History of Geology and Palaeontology."

Maria Ogilvie continued her studies and continued to publish. In 1913 she was preparing another important work about the geology and geomorphology of the Dolomites, to be published in Germany, but in 1914 with the onset of World War I. and the death of the publisher, the finished maps, plates and manuscripts were lost in the general chaos.
In 1922 she returned into the Dolomites, where she encountered the young paleontologist Julius Pia, who, during the war, had carried out research in the Dolomites. Together they explored many times the Dolomites.

Landscape profile of the Langkofel-massif after GORDON & PIA (1939): Zur Geologie der Langkofelgruppe in den Südtiroler Dolomiten. Maria Matilda included hand-drawn sketches in her research.

Apart from scientific papers, Maria Matilda published also one of the first examples of geological guide books for the Dolomites. To honor her contributions to earth sciences in 2000 a new fossil fern genus, discovered in Triassic sediments, was named Gordonopteris lorigae.

Interested in reading more? Try:

WACHTLER, M. & BUREK, C.V. (2007): Maria Matilda Ogilvie Gordon (1864-1939): a Scottish researcher in the Alps. In BUREK, C. V. & HIGGS, B. (eds): The Role of Women in the History of Geology. Geological Society: 305-317

Radioactivity and Earth's Age

In the 19th century, the discrepancy between the age of Earth and the age of the cosmos posed a great problem to scientists. Geologists had calculated, using methods like erosion or sedimentation rates, ages for Earth spanning from three million to fifteen billion years. Physicists and astronomers, based mostly on the energy output of stars, calculated an age for the universe spanning from twenty million to ten billion years - so in many models of the cosmos, Earth seemed to be too young or too old to fit in. In August 1893, during a meeting of the American Association for the Advancement of Science, geologist Charles D. Walcott (1850-1927) summarized the debate as follows:

"Of all subjects of speculative geology, few are more attractive or more uncertain in positive results than geological time. The physicists have drawn the lines closer and closer until the geologist is told that he must bring his estimates of the age of the earth within a limit of from ten to thirty millions of years. The geologist masses his observations and replies that more time is required, and suggests to the physicist that there may be an error somewhere in his data or the method of his treatment."

In 1896 the French physicist Henri Becquerel (1852-1908), based on Conrad Röntgen's (1845-1923) research, discovered that naturally occurring elements, like uranium, also emit X-rays and in 1897 Polish physicist Marie Curie (1867-1934) coined the term radioactivity to describe this energy of unknown origin. Her husband, Pierre Curie (1859-1906), realized that this energy from radioactive decay must be considered when calculating the age of Earth. Physicists supporting a young Earth based their calculations on a quickly cooling Earth. However, radioactive decay in Earth's interior provided a continuous source of energy and heat, therefore Earth was cooling slowly and so could be quite old.

Radioactive decay or another similar long-lasting and high-energy source (nuclear fusion was discovered later) could also explain how stars could produce light and heat for very long periods of time. The notion that stars or the sun had to be young (in most calculations younger than Earth) could also be dismissed.

But even better - the discovery of radioactivity provided not only indirect evidence of an old Earth but by measuring the constant decay it was also possible to calculate the exact age of a mineral, a rock and even of Earth.

High-energy rays, derived from radioactive decay, form a halo of alteration around a mineral grain in the larger biotite-crystal, image from J. JOYLE (1909): Radioactivity and geology, an account of the influence of radioactive energy on terrestrial history.

A 3,000 Year Old Geological Map

According to ancient historians, gold in the kingdom of Egypt was as common as is sand in the desert. It´s true that Egypt exported for centuries large quantities, and even the Romans mined gold in Egypt (last attempts for gold mining were done in the 1950s). However, where the ancient mines were once located became forgotten over time.
 

Archaeologist Rosemarie and Dietrich Klemm discovered in the 1980s the lost mines following an ancient "geological" map. Discovered near modern Luxor (ancient Thebes) between 1814 and 1821, the papyrus/map was brought to Italy and is today hosted in the collection of the Museum of Egyptian History in Turin. The Turin papyrus dates back to 1,150 BC and  was prepared for an expedition led by Ramesses IV.

Reconstructed map of the Turin papyrus, image source. Pinkish-red= gold-bearing rocks, dark-green= rocks for construction.

Modern interpretation of geology , red=Hammamat-fm sandstone and volcanics, blue= Atalla-Serpentinite, yellow & green= Fawakhir-Granite.

The map shows the landscape around an unknown oasis. Inscriptions describe the "Mountain of the Gold”, the “Mountain of the Silver”, but also the location of the “Village of the Miners”, the "Temple of Amun", the streets to the (Red-) Sea and a street to Ta-menti (an unknown locality). The different colors of the map are inspired by the real colors of the rocks, reddish feldspar-granite (Fawakhir-Granite), dark Atalla-Serpentinite and Hammamat-Formation, and yellow for the sand of the desert. A dry river runs down the entire valley, eroding and transprting the rocks, as shown by the pebbles in different colors. A quarry of bekhen stone, a blue-green sandstone used to carve statues, is shown, as are many mines for gold. The most important indication was the location of a well near the village. Thanks to this well, archaeologists identified the area shown on the map. The ancient mountains of gold and silver are situated in the Wadi Hammamat, near Bir-Um-Fawakhir, an ancient miner settlement, almost 100km east of Luxor. Following the indications of the map into the field, the archaeologist discovered ancient signs of mining, like 50m long tunnels following quartz veins. The important veins are shown as lines in the Turin map. The gold is found as tiny fragments in the massive quartz, almost invisible to the naked eye. That ancient Egyptians found it, is a impressive evidence for their (emprical) geological knowledge. Already in 3,200 BC professional geological prospectors, called “sementi“, searched for deposits and veins of gold, to meet the demand of the divine pharao. Tutankhamun’s tomb alone was filled with more than 500 items, many made of pure gold. Following the veins into the mountain, the miners extracted the rock, crushing it, and washing the heavy gold out. Large deposits of quartz sand, the remains of the crushed rocks, still today testimony the hard work done by the ancient miners.

Frauds, Fakes and Fossils

“What are they?

Creations of mind?- The mind can make Substance,
and people planets of its own
With beings brighter than have been, and give
A breath to forms which can outlive all flesh”
“The Dream“, Lord Bryon (1788-1824)

In the year 1725 the professor of medicine and personal physician of the bishop of the German town of Würzburg, Dr. Johann Bartholomäus Adam Beringer (1667-1738), was approached by three chaps, who offered him the possibility to purchase some strange stones they had found in the fields.

Beringer recognized the unique value of the discovery and paid a rich reward for these and further specimens. After a short time he possessed the greatest collection of stones displaying on the surface various bugs, molluscs, plants, birds, mammals, stars, suns and even Hebraic letters.
One year later, in 1726, Beringer published a monographic work with 14 sections and 21 plates depicting 204 specimens of his collection: the “Lithographia Wirceburgensis”, assuring the veracity of the stones as a divine miracle.

But then the scandal was revealed – the chaps admitted that the stones were artificially carved, incited by two peers of Beringer, the mathematician Jean Ignace Roderique (1697-1756) and the theologian Johann Georg von Eckhardt (1664-1730). The two scholars admitted that the fraud was their revenge for the presumptuous behaviour of Beringer and intended to expose his credulity and incompetence. The public was not amused by the childish behaviour of all the involved persons: The reputation of all the three scholars was ruined, Roderique and Eckhardt were forced to leave the city and Beringer tried to minimize the damage by destroying almost all of the printed copies and the printing plates of his book. He never recovered from the humiliation and died embittered years later.
Almost every student of earth sciences knows this or a similar version of the myth, often told in textbooks as warning of blind faith and argument from authority. The beautiful carved stones of limestone are today remembered as “Würzburger Lügensteine” – the infamous “lying stones of Würzburg“.

However careful study of the still existing stones and the preserved historic documents of the lawsuit that investigated the claims of fraud at Beringer´s time depict a much more complicated “criminal case.”

Today 434 lying stones survive, 494 are depicted in the Lithographia Wirceburgensis and Beringer himself claims that he possessed more than 2.000. However considering the short period in which the “discoveries” took place (less than one year) it seems more reasonable to assume that this number is deliberately exaggerated. Estimated 600 to 1.100 true lying stones seem a more plausible number.

Beringer affirms that he received or discovered the first stones in May of the year 1725. Between June and November he hired the two brothers Hehn, the chap Zänger and later a fourth person, which name is not recorded, to collect further stones on the presumed site of the first discovery.

Beringer began almost immediately to describe the various stones and ordered the printing plates for his book; he also published a preview of his work in October of 1725. Already then first doubts were cast on the veracity of the stones, but Beringer presented various witnesses that could testify that indeed the stones were found during the excavations on a hill near Würzburg. Johann Georg von Eckhardt, and later Jean Ignace Roderique, were send to investigate the site but couldn’t find any stone there. However they also couldn’t provide evidence to dismiss Beringer´s claims.

It is important to note that Beringer never affirmed that the stones were true petrifactions (as the petrified remains of organisms killed by the biblical flood) and he even states that the stones differ from the true petrifactions found in the hills near Würzburg. He discusses in great detail the various explanations proposed for the origin of petrifactions in the first chapters of “his” Lithographia (as a matter of fact the book is published as doctoral thesis under the name of one of Beringer´s students – Georg Ludwig Hueber – but his contribution is limited to an introduction of nine pages) and examines the various hypotheses, but dismiss all in favour of a literally “miracle”. God himself created these stones and the recognizable carving spurs (!) on the stones are only a trace of the power of god creating these figures.

In spring of 1726 Beringer received some rocks from the fourth chap, this time in fact fabricated by Roderique to reveal the artificial nature of the stones. The fraud is revealed, even in the presence of the bishop (the Lithographia is dedicated to him), but Beringer simply modifies some chapters of the Lithographia, still in press, claiming that it is now only proven that the last stones are fakes and the first generation is still evidence for (literally) god’s hand carving the rocks. Beringer is apparently so self-confident in his position that he initiates a process against the claims of fraud regarding his persona. In the process, that will last until after the publication of the Lithographia, the incriminated chaps will only admit to have sold the stones to Beringer, but not to have carved the figures. Considering the depictions of exotic animals and even Hebraic letters on the lying stones it is in fact difficult to image that people from a rural area with no naturalistic background would be able to execute such an elaborate hoax.

There is no doubt that the scholar Roderique manufactured some of the stones, however he arrived to Würzburg only in the winter 1725-1726, so he can not be responsible for the first generations of stones described by Beringer already in October of 1725. Roderique left Würzburg voluntarily in 1730, the revealed “scandal” had no influence on his career and he died as respected scholar and publisher years later. There is no evidence that Eckhart played a major role in the entire story, apart the first investigation of the supposed excavation site. Both Roderique and Eckhart had no need for revenge versus Beringer and were relatively unsuccessful in the attempt to discredit the lying stones, as they – or others, could never demonstrate that that the first stones were fakes.

But who then faked the first lying stones?

Beringer didn’t suffer too much from the supposed scandal, not only didn’t he even try to prevent the publication of the Lithographia after the first claims of fraud (there was still plenty of time left), but he retained his position and reputation. In 1767 even a second edition of the Lithographia was published with the original plates (not even touched by Beringer) of the first edition.
His hypothesis of divine intervention on the rocks was never ridiculed in a time when fossils were anyway considered the vestiges of a biblical flood. However it is true that after the newspapers revealed that it was possible to fake the stones (like done by Roderique) the lying stones could no longer be used to support uncritically the "divine crafted" hypothesis.

Only after Beringer´s death his strange behaviour, he remained unimpressed by all the claims of fraud, was interpreted by many authors as simple ignorance or even criminal stubbornness. But maybe he remained calm because he was sure that nobody could definitely prove that the first generations of stones were fakes, simply because he knew who carved the figures in the stones. Beringer had the naturalistic knowledge and probably also the contacts to professional craftsmen to perpetuate such an elaborate hoax – even if we never will know the entire truth, one fact is clear, the modern myth of the lying stones is itself a lie…

Bibliography:

BEHRINGER, J.B.A. & HUEBER, G.L. (1726): Litographiae Wirceburgensis, ducentis lapidum figuratorum, a potiori insectiformium, prodigiosis imaginibus exornatae specimen. Würzburg 1726. Scan by www.BioLib.de
NIEBUHR, B. & GEYER, G. (2005): Beringers Lügensteine: 493 Corpora Delicti zwischen Dichtung und Wahrheit. Beringeria Sonderheft 5, Teil II: 188

The Four Layers of Earth

In a letter dated to March 30, 1759 the Italian mining engineer Giovanni Arduino (1714-1795) proposed to the physician and fossil collector Prof. Antonio Vallisnieri the subdivision of earth’s crust in various types, or layers, of rocks.

Based on his observations along the foothills of the Alps, Arduino recognized a stratigraphic column with four rock-layers: unstratified or poorly stratified crystalline rocks (or “Primary Rocks“, survived into the 20th century as “Paleozoic“ epoch), stratified rocks (“Secondary Rocks“, or “Mesozoic“), more recent, as yet unconsolidated, sediments (“Tertiary Rocks“) and finally all volcanic rocks.

Arduino used a section of rocks exposed in the Val d´Agno to explain his classification scheme. The numbers refer to the thickness of the strata, the letters to the description in the accompanying text. The extremely tattered state of the original drawing suggests that Arduino demonstrated it repeatedly to the many naturalists who visited him.

Bibliography:

VAI, G.B. (2007): A history of chronostratigraphy. Stratigraphy Vol.4 No. 2/3: 83-97

A History of Geological Maps: I. From Outcrop to the first Map

March 23, 1769 marks the birthday of pioneering stratigrapher William Smith, who is also credited as author of the first modern geological map, however like many other great accomplishments also Smith’s idea of depicting the distribution of rocks on a topographic map didn’t materialize out of nowhere.

The German mining engineer Georgius Agricola (1494-1555) dedicated in his “De re metallica” (1556) -  an early  textbook on mining technologies – an entire chapter to the distribution of valuable rocks in earth’s crust. The written description is correlated with various figures, showing in a sort of combined landscape – section the distribution, thickness and direction inside the mountain of the mineralized veins.

 

Fig.1. Veins and mineral seams, figure from “De re metallica”, not a real map, however directions are given on the borders.

The idea of a real map of rock-distribution was proposed first in 1684 by the British physician and naturalist Martin Lister (1639-1712). Lister suggested that the distribution of the different soil types of the British landscape could accurately be represented on a topographic map.

“The Soil might either be coloured, by variety of Lines, or Etchings; but the great care must be, very exactly to note upon the Map, where such and such Soiles are bounded…Now if it were noted, how far these extended, and the limits of each Soil appeared on a Map, something more might be comprehended from the whole, and from every part, then I can possibly foresee, which would make such a labour very well worth the pains.“
 

As – so Lister continues – the soil types correlate with the underlying bedrock, by mapping the soils one could also map the rocks hidden in the underground.

However Lister never realized a real map based on this theoretical premise. It was the Italian Count Luigi Ferdinando Marsili (1658-1730) who made the next important step. As military engineer Marsigli traveled widely in Italy, France, Germany, the Balkans and Turkey, creating topographic maps for military use of the visited countries. An exact representation of the landscape was essential to plan movements of an army or identify the best locations for fortifications. Marsigli became a keen observer and a skilled cartographer of the landscape, sketching rock outcrops or  prominent features of the landscape. After an unfortunate military campaign in Germany, Marsigli was accused of cowardice, his military career ruined he used his acquired skills to create maps for more peaceful applications.

 

Fig.2. Section combined with a map of a silvermine, published in - "Mappa metalographica…[]" by Luigi Ferdinando Marsili, he added also some geological information (lower right corner) with a detailed rock-section - "Upper rock", "Vein" with mined "Ore" and "Lower Quartz".

In 1726 he published a map of the mining districts in Hungary and sketched the distribution of gypsum and sulfur deposits near his hometown Bologna (1717). In his sketch he connected the single gypsum quarries and outcrops along rivers with a shaded area, delimiting so the folded gypsum-bearing rocks. This map is important as it displays a first approach to the problem all geologists must face – not only documenting the visible outcrop of a rock or the position of a mine or quarry (such maps existed already), but interpolating the distribution of the not accessible part of  a geological formation.

 

Fig.3. The map from “Atlas et Description Minéralogiques de la France” (1780), by French pharmacist and botanist Jean-Étienne Guettard, shows the distribution of outcrops with minerals, fossils or rocks. Such mineralogical maps predate true geological maps, showing sites of geological interest, however lacking the interpolation between the single “data points” (image in public domain, originally posted by BibliOdyssey).

It may surprises that despite many naturalist had already produced very detailed descriptions and maps of single outcrops, almost nobody made a connection between sites with similar rocks. But not only was the unequivocal identification of geologic formations at the time still very difficult, many naturalists considered connecting single outcrops by a presumed (not visible at the surface) extension of the rocks as unscientific speculation. This aversion of early geognosts to geological maps is exemplified by the strange behavior of naturalist Jean-Étienne Guettard (1715-1786), famous for his detailed mineralogical and volcanological maps. Guettard in 1777, after eleven years of  hard work, abandoned the prestigious project by the French minister of Mining to produce a series of geological maps of France. He simply couldn’t overcome the idea that a map should represent only facts (in this case outcrops) – but a blank map with just some isolated spots of color wasn’t exactly what the French authorities wanted.

Maybe the first true geological map was drawn by an anonymous naval cartographer in 1757. In the outlines of the German island of Heligoland he added boundaries between four different rock types: Kreide (chalk), Muschelkalkstein (limestone), Bunter Sandstein (sandstone) and Kohle (coal beds). The map depicts the boundaries of the various geological formations even below the sea.

As the author, also the intended use of this map is unknown. The historian of geology  – David. R. Oldroyd – speculates that the map maybe could be used as aid to navigation, as sailors could determine their position by evaluating the rocks and sediments dredged from the seafloor.

To be continued…

Bibliography:

FRANCESCHELLI, C. & MARABINI, S. (2006): Luigi Ferdinando Marsili (1658-1730): A pioneer in geomorphological and archaeological surveying. In VAI, G.B. ed, The origins of geology in Italy: Geological Society of America Special Paper 411: 129-139
OLDROYD, D. (2013): Maps as pictures or diagrams: The early development of geological maps. In BAKER, V.R. ed, Rethinking the fabric of geology: Geological Society of America Special Paper 502: 41-101

A History of the Use of Illustrations in the Geosciences: I. Seeing is Believing...

The progress made in understanding realistic landscape-views and the rediscovery of ancient encyclopedias (like the works by Pliny the Elder) inspired Renaissance naturalists to adopt an exact and systematic approach to describe the curiosities found in the natural world. As most information as possible should be associated to every studied object – compiled from the works of ancient authors, own observations, may also supposed medical and magical properties, a good description should also include a detailed figure showing the described specimen (at the time a very expensive approach, as artists and engravers had to be hired).
 

One of the most extraordinary examples of this new approach to nature is the work by Italian naturalist Ulisse Aldrovandi (1522-1605) – his motto was “to understand plants and animals there is no better way than to depict them from life“. The commissioned figures for his encyclopedia on animals and freaks of nature are indeed of exquisite quality, even more if compared to the at the time still very popular bestiaries with their fanciful illustrations of mythical monsters. 

Aldrovandi included also some drawings of fossils in his work, not of such high quality as the depicted animals, however good enough to still identify the real fossil models.

The first book to depict in a systematic order fossils was published in 1565 by naturalist Conrad Gesner (1516- 1565). In "De Rerum fossilium, Lapidum et Gemmarum maxime, figuris et similitudinis Liber” (On Fossil Objects), Gesner compares fossil sea urchins with living specimens, arguing that some fossils are lithified organisms. However Gesner observed and shows also differences between living organisms and fossils, arguing that those differences are evidence that other fossils are of inorganic origin. The figures play an important role to support his observations, theories and make them accessible also to other scholars. Also Danish anatomist and naturalist Niels Stensen uses in 1667 a similar approach when showing the organic nature of fossil shark teeth.
 

Fig.1. Shark teeth depicted in C. Gesner´s "De Rerum fossilium...[]”. Such figures made it possible for other naturalists to compare their fossils with specimens of other collectors or hosted in private, non easily accessible, collections. However the quality of the used wood cuts was still poor and were soon replaced by copper engravings, with a higher reproduction quality.
 

Naturalist Federico Angelo Cesi (1585–1630) founded in 1603 the Accademia dei Lincei (Academy of Lynx, as a tribute to the sharpness of vision of this animal). This Italian association of scholars was devoted to study and classify all of nature, one member, Fabio Collona, predated even Steno in the interpretation of fossil shark teeth. The Accademia supported the use of drawings in the member´s publications and in the end it possessed more than 7.000 drawings and paintings in its collection. Cesi was interested in the classification and origin of what appeared to be fossil wood, emerging from Pliocene sediments of Umbria. In his posthumously (1637) published work, according to the principles of the association, he not only features drawings of the collected and studied specimens, but also – for the very first time – drawings from the field. In Cesi´s field drawings he documents the landscape of the fossil sites, the horizon of the wood samples, also the work done, like the excavation of large logs. Some drawings are accompanied by descriptions of the samples, with measurements and notes on color, shape and weight of specimens. Only 200 years later geological works will equal Cesi´s notes.
 

Fig.2. Drawing of field site showing a gully with accumulation of fossil wood.

 

Fig.3. Published plate (1637) of a fossil log as found and excavated in situ.

Fig.4. Fossil wood shown in a classic manner, as collection of specimens.

Bibliography:

MARRA, A,C, (2004): Iconografia dei fossili tra scienza, filosofia e istificazione. PaleoItalia, No.10: 3-8
SCOTT, A.C. (2001): Federico Cesi and his field study on the origin of fossils between 1610 and 1630. Endeavour, Vol.25(3): 93-103

Geomorphologic Groundhog Day !

We don’t know how much wood a woodchuck would chuck if he could chuck wood, but we know how much sediment he moves per year…

Biogeomorphology, also referred as ecogeomorphology or sometimes as zoogeomorphology, is the study of the links between ecology and geomorphology, or in simple terms between life-forms and landforms. Such interactions range from simple tracks left by an organism in the landscape to the complex cycles of energy and matter transfer (like for the element carbon) between the biosphere and the lithosphere.

The role of animals in the evolution of a landscape is still poorly studied, but one of the most interesting processes modifying a landscape involves digging animals.
 

Mammals move earth for two reasons – to collect food (digging up roots or other animals) or to dig a burrow. Large rodents, like the groundhogs (genus Marmota), are feared for their burrowing habits in agricultural areas, as the entrance to – or the collapse of – their extensive burrow systems can pose a hazard for machines or the livestock.
 
The density of burrows varies with the climate and environment, for example a humid mountain area can provide more food and guarantee the survival of more individuals than a dry steppe.
The increased activity of a large number of marmots can influence the surface runoff and erosion of a mountain slope and redistribute humus, moisture and mineral components in the soil profile. 

The research by TADZHIYEV & ODINOSHOYEV (1978) “Influence of marmots on soil cover of the eastern Pamirs” on the digging capacity of red marmots showed that they could move almost 28 cubic meter (that´s almost a medium-sized truck) of earth per hectare  in a single year. This suggests that on local scale marmots and relatives can play a quite important role as a geomorphologic factor.

Bibliography:

BUTLER, D.R. (2009) Zoogeomorphology – Animals as Geomorphic Agents. Cambridge University Press: 239
GOUDIE, A.S. (ed) (2001): Encyclopedia of Geomorphology Volume 1 A-I. Routledge, Taylor & Francis Group, London – New York: 1156

"Mad about Geology" - Geologizing with Darwin

"A journey of a thousand miles begins with a single step."
Chinese proverb

January 16, 1832 the H.M.S.Beagle, with Charles Darwin on board, arrived to the barren "Quail Island" (today Island of Santa Maria, Cape Verde Islands). It was the first time that Darwin geologized alone in a foreign country, however he was well prepared...

In 1831 Charles R. Darwin went on a life changing field trip – not to mention the voyage on board of the Beagle later in that year. The botanist John Stevens Henslow introduced the 22-year old Darwin to 46-year old Adam Sedgwick, self-educated naturalist and professor for geology and botany at Cambridge University. Even if Darwin was a student at Cambridge, he seems not to have attended Sedgwick´s lectures on geology, as he regrets in an autobiographic note that

“Had I done so I should probably have become a geologist earlier than I did.“

At the time Sedgwick was studying the geology of Wales and invited Darwin to join him in a field trip from Shrewsbury, Darwin’s hometown. Sedgwick was especially interested in the stratigraphic succession exposed in North Wales (Sedgwick will later use his observations to define the geologic epoch of the “Cambrian“) and Darwin was interested to acquire the basics of geological field work. Darwin wrote in July to a friend

“I am now mad about Geology & daresay I shall put a plan which I am now hatching, into execution sometime in August, …[]“

Darwin was well equipped for his geological field investigation. He purchased a new clinometer with an incorporated compass for structural analysis and a geological hammer for the collection of rocks.
 

He visited Llanymynech (located west of Shrewsbury) alone and "on my return to Shropshire I examined sections and coloured a map of parts round Shrewsbury", mapping outcrops of sandstone and coal measures.

Sedgwick arrived to Shrewsbury on the 2nd August, visiting in the next days some outcrops located south-west of the city, where he recognized limestone and volcanic rocks. It’s not clear if he met Darwin already, for sure both geologist left Shrewsbury on August 5th venturing north. They spend a week trying to find Old Red Sandstone. Sedgwick was interested in the geological formations underlying the Old Red Sandstone (Silurian to Carboniferous in age), as the age of these rocks was still unknown and according to the large-scale geological map published by George Greenough in 1819 such rocks should be found in the area. However despite their combined efforts and a meeting in Llangollen with another great geologist, Robert Dawson, no Old Red Sandstone was found.

In his autobiography Darwin affirms that he left Sedgwick at Capel Curig, however it may be possible that he visited with Sedgwick the island of Anglesey and even made a short trip to Dublin (as Sedgwick did, on Anglesey he found also the Red Sandstone he was after). During his voyage on the Beagle, Darwin will recognize on the Cape Verde Islands Serpentine, this kind of rock he could have only previously seen on Anglesey - or maybe he used Sedgwick notes.

Fig.1. Geology of North Wales, after Reynolds 1860, 1889, Woodward 1904 (click to enlarge), with the route of Darwin and Sedgwick after ROBERTS 2001. The first part of the route, starting from Shrewsbury, follows the contact of the Silurian limestone (pink-coloured) and younger sediments (blue colour; Carboniferous to Permian), as both geologist hoped to find the Old Red Sandstone formation. Sedgwick found it (dark-orange) only on the island of Anglesey.

Twenty pages of notes made by Darwin during this tour are still today conserved – in his autobiography he will later remember: “This tour was of decided use in teaching me a little how to make out the geology of a country…”
 

When Darwin returned home to Shrewsbury August 29th a letter by botanist John Stevens Henslow, in name of Captain Robert FitzRoy, was offering him a position as gentlemen companion and naturalist on board of the Beagle. 

Read on...

Bibliography:

HERBERT, S. (2005): Charles Darwin, Geologist. Cornell University Press: 485
ROBERTS, M. (2001): Just before the Beagle: Charles Darwin’s geological fieldwork in Wales, summer 1831. Endeavour Vol. 25(1): 33-37

Nicolas Steno and the Origin of Fossils

In October 1666 a large shark was captured by a French fishing boat in the sea of Livorno (today Italy, at the time County of Tuscany), pulled onto the shore, the animal was beaten to death and dismembered, as the body was quite too heavy to be transported and only the head was saved. In Florence the Danish anatomist and naturalist Niels Stensen or latinized Nicolas Steno (born January 11, 1638) was asked to dissect this head. 

Stensen observed various anatomical particularities: the skin was covered by glands, secreting a reddish slime. Steno assumed that this slime would keep the skin smooth, helping the animal to move in water (today the ampullae of Lorenzini are considered part of an organ to sense electromagnetic fields). He noted also the structure of the brain, arguing that it appeared quite too small to coordinate such a large animal, so also the spine must have some role in (unconscious) movements (like reflexes). Finally Steno studied the mouth, noting the ranks of sharp teeth.
 

Steno, after the anatomical description, adds a chapter comparing these teeth with common fossils - the Glossopetrae or tongue stones. It´s important to note that Steno was not the first to speculate over the organic origin of such fossils, already in 1616 the Italian Fabio Colonna (1567-1640) explained glossopetrae as shark teeth. However many naturalist argued that the organic origin of fossils could not explain how such remains of sea animals  could become entrapped in rocks, found on dry land and even high in the mountains. 

Fig.1. Recent, mummified shark head.
 

But Steno was for the first time able to explain why these fossilized teeth were found inside rocks, far distant to the modern sea.  Steno had already observed fossils hosted in the Royal Danish Kunstkammer (Copenhagen) and in a private note he writes "Snails, shells, oysters, fish, etc., found petrified on places far remote from the sea. Either they have remained there after an ancient flood or because the bed of the seas has slowly been changed. On the change of the surface of the earth I plan a book, etc."
 

Fig.2. Steno's figure of a dissected shark head, comparing the teeth of a modern shark to the fossil Glossopetrae, from "Elementorum myologiæ specimen, seu musculi descriptio geometrica : cui accedunt Canis Carchariæ dissectum caput, et dissectus piscis ex Canum genere" (1667).
 

He also studied outcrops of layered rocks in Tuscany, recognizing the sedimentary origin and a stratigraphic order. However only with the description of the shark head he combines all his observations in one "geo-theory":

• Fossils, resembling modern animals, are not found in recent soils of dry land. If fossils were of inorganic nature, however we should find them in every kind of soil and rocks.
• The layering was formed by sedimentary deposition, the soil where fossils are found once was therefore a sort of liquid mud, so that bodies of dying animals could become imbedded into it
• Those soils were deposited and therefore covered once by water, this explains why fossils resemble animals of the sea
• The sea can become repeatedly dry land by movements and disturbances of earth´s crust , the fossils in the mud are uplifted, the mud dries and becomes hard soil, therefore fossils can be found high in the mountains

However Steno's work, like the work of many others before him, was ignored for decades. Then a certain John Woodward, considered an amateur physician and naturalist by some, by others a quack, used/stole the principles formulated by Steno in his 1695 book "An Essay toward a Natural History of the Earth". The best part of work, thought to support the idea of the biblical sin flood as origin of the fossils, were the text passages copied from Steno.
However the book of Woodward and the principles of Steno used in it initiated a new interest in the study of sedimentary rocks.

Bibliography:

KARDEL, T. & MAQUET, P. (eds.) (2013): Nicolaus Steno - Biography and Original Papers of a 17th Century Scientist. Springer Publishing: 739

A Concise History of Geological Maps: From Outcrop to the first Map

March 23, 1769 marks the birthday of pioneering stratigrapher William Smith, who is also credited with creating the first useful geological map, however like many other great accomplishments also Smith’s idea of depicting the distribution of rocks on a topographic map didn’t materialize out of nowhere.

Geologizing with Darwin and Sedgwick

"Therefore on my return to Shropshire I examined sections and coloured a map of parts round Shrewsbury."

In 1831 Charles Darwin attended a life changing expedition - not considering the voyage on board of the "H.M.S. Beagle". The botanist John Stevens Henslow introduced the 22-year old Darwin to 46-year old Adam Sedgwick, self-educated naturalist and professor for geology and botany at Cambridge University (1785 - January 27, 1873). Even if Darwin was a student at Cambridge, he seems not to have attended Sedgwick´s lectures on geology, as he regrets in an autobiographic note that

"Had I done so I should probably have become a geologist earlier than I did."

At the time Sedgwick was studying the geology of Wales and invited Darwin to join him at a field trip from Shrewsbury, Darwin's hometown. Sedgwick was especially interested in the stratigraphic succession exposed in North Wales (Sedgwick will later use his observations to define the geologic epoch of the "Cambrian"), Darwin was interested to acquire the basics of geological field work. Darwin wrote in July to a friend

 "I am now mad about Geology & daresay I shall put a plan which I am now hatching, into execution sometime in August, …[]"

Darwin was well equipped for his geological field investigation. He purchased a new clinometer with an incorporated compass for structural analysis, a geological hammer for the collection of rocks and various copies of topographic and geological maps.

He visited Llanymynech (west of Shrewsbury) alone and started to colour a map, mapping outcrops of sandstone and coal measures.

Fig.1. Geology of North Wales, after WOODWARD 1904, REYNOLDS 1860, 1889, with the route of Darwin and Sedgwick after ROBERTS 2001. The first part of the route, starting from Shrewsbury, follows the contact of the Silurian limestone (pink-colored) and younger sediments (blue color; Carboniferous to Permian), as both geologist hoped to find the Old Red Sandstone formation. Sedgwick found it (dark-orange) only on the island of Anglesey (original map in public domain, click on the image to enlarge).

Sedgwick arrived to Shrewsbury on 2nd August, visiting in the next days some outcrops located south-west of the city, where he recognized limestone and volcanic rocks. It's not clear if he met Darwin already, for sure both geologist left Shrewsbury on 5th August venturing north. They spend a week trying to find Old Red Sandstone. Sedgwick was interested in the geological formations underlying the Old Red Sandstone (Silurian to Carboniferous in age), as the age of these rocks was still unknown and according to the large-scale geological map published by George Greenough in 1819 such rocks should be found in the area. However - despite their combined efforts - and a meeting in Llangollen with another great geologist, Robert Dawson, no Old Red Sandstone was found.

 In his autobiography Darwin affirms that he left Sedgwick at Capel Curig, however it seems reasonable to assume that he visited with Sedgwick the island of Anglesey and even made a short trip to Dublin (as Sedgwick did, on Anglesey he found also the Red Sandstone he was after). During his voyage on the Beagle, Darwin will recognize on the Cape Verde Islands Serpentine, this kind of rock he could have only previously seen on Anglesey.
 

Twenty pages of notes made by Darwin during this tour are still today conserved in the library of the Cambridge University. In his private autobiography he will later remember: "This tour was of decided use in teaching me a little how to make out the geology of a country…"
When Darwin returned to Shrewsbury on 29th August, a letter from Captain Robert FitzRoy was offering him a position as gentlemen companion on board of the Beagle. The rest is history.

Bibliography:

HERBERT, S. (2005): Charles Darwin, Geologist. Cornell University Press: 485
ROBERTS, M. (2001): Just before the Beagle: Charles Darwin's geological fieldwork in Wales, summer 1831. Endeavour Vol. 25(1): 33-37

John Joly tracking Oldhamia

John Joly (1857-1933) was an Irish professor of geology, trained as engineer, who made important contributions to geology, mineralogy, geophysics, tectonics, geochronology, but also optics, chemistry, photography, mechanics and laboratory equipment. He discovered his love for geology in 1880, during a field trip into the hills south of Dublin, where he collected various specimens of minerals and fossils. Seventeen years later he managed to convince the Trinity College that he, due his experience and expertise in the field, was the right man for the, at the time, vacant position as geology professor.

During a walk in County Wicklow in the winter of 1984 he observed how ice crystals had formed an intricate pattern in the muddy soil. The pattern reminded him of Oldhamia, a trace fossil of unknown origin he had collected in Cambrian (541-485 million years ago) rocks at Bray Head.

Could it be that these presumed fossils were in fact of inorganic nature? 

 "Elements of Geology" by C. Lyell (1871)

Joly tried to replicate the patterns in the laboratory by freezing various samples of soil and mud, and succeeded to reproduce a pattern resembling an ichnofossi - Oldhamia radiata. However he failed to reproduce other similar ichnofossils with a more complex pattern, like Oldhamia antiqua. He blamed his failure in part to problems to exactly reproduce the grain size distribution of the sediments preserving the traces.

Later Joyle realized some other problems in his hypothesis with the inorganic origin of the Oldhamia fossils. O. radiata was found in the field always as depression, O. antiqua in relief, probably resulting from the relationship between the bedding plane and the mechanism by which they were produced. 

An inorganic mechanism, like freezing, would probably show no such preferences. Today it is also known that the Cambrian sediments where Oldhamia fossils can be found were deposited in deep water, not as Joly imagined along shores or tidal flats, where the mud could freeze.

 
Bibliography:

JACKSON, P.N.W. (2011): History of Ichnology: John Joly (1857-1933) on Oldhamia: Poetic and Scientific Observations. Ichnos 18(4): 209-212

Paleoseismology of the Anatolian and Caucasus Region

"The people of Behura fled from my weapons into the mountains of Uschkiani and Banni. I surrounded part of them and killed all. The others that could flee were burned by the earth god Teischeba."
Description of the military campaign of king Argischti I in 780-756 B.C.

Turkey is characterized by two main strike-slip fault systems - the North Anatolian Fault (NAF) and the East Anatolian Fault - that in the Caucasus region merge together in a complex tectonic system dominated by compressional thrust faulting. 

Devastating earthquakes of the last decades occurred mainly along the dextral North Anatolian Fault that forms the plate boundary between the Anatolian and Eurasian plates. This is also a densely populated region with the city of Istanbul as one of the most important harbours of the Mediterranean Sea. 

May 10, 1566 the cities of Rossana and Constantinople (modern Istanbul) were hit by an earthquake that caused the collapse of buildings. Some 50 years earlier (October 10, 1509) Constantinople had been affected by an even worse disaster, killing 13.000 people. 

During the 20th century seismic activity apparently moved along the NAF from the east to the west, in 1999 two strong earthquakes hit the city of Izmit, killing 17.000 people.

In Armenia the strongest earthquake since centuries occurred December 7, 1988, it destroyed the city of Spitak and killed 25.000 people.

Fig.1. Simplified tectonic map of the Caucasus region with the locations of important earthquakes - the recent earthquake at Van, the earthquake of Spitak and the historic earthquake of Behura. Various sections of the North Anatolian Fault show a progressive younger activity from the east to the west (colour coded). According to some models this could suggest that stress is released following the fault system and that Istanbul could be hit again by a stronger earthquake in the future.

The region around Lake Van was repeatedly hit in the present and the past by strong earthquakes. Cronicles report of havoc and destruction in the 4th century and again in the 10th century, in 1976 an earthquake in the Van Province caused 4.000 victims.
One of the oldest earthquakes in the Caucasus region was inferred from historic descriptions and confirmed by geologic evidence -it dates back to more than 2.700 years. 

A French-Armenian team of paleoseismologists searching for suitable sites for their research discovered on aerial photographies the ruins of the ancient city of Behura.
Paleoseismology tries to collect evidence for earthquakes based on both archaeological as geologic proxies to improve the knowledge of the seismic history of a region. Knowing this history of a region can help to estimate the time-intervals occurring between earthquakes of a certain magnitude.
Ancient documents refer to a city located in the area around the Lake Sevan that was conquered in 780 to 756 B.C. by the great king Argischti I, the description of the siege is curious, mentioning fire, ash and clouds (send supposedly by the earth god Teischeba) helping destroying the city. Maybe this is the description of a volcanic eruption accompanied by earthquakes. Nearby the site relatively unweathered and therefore probably young lava flows coming from the volcano Porak were discovered,
In Behura the excavation of a trench revealed a complex stratigraphy of soils, a displaced wall, scree deposits and younger soils, suggesting that the city was in fact destroyed by an earthquake.

Bibliography:

HERVÈ, P. & KARAKHANIAN, A. (2001): Der Untergand von Behura. Spektrum der Wissenschaft -Dossier 2 "Die Unruhige Erde": 31-35
JACOB, K. (2006): Istanbul - Warten auf den großen Schlag. Bild der Wissenschaft 2: 48-53