Geologists in the land of the Kangaroo

Terra Australis - the southern continent had been “discovered” by Europeans already in 1606, but only in 1642 the size of the new “island” becomes clear and the first geological observations  were made only in the early 19th century.

October 1800 two ships – the “Geographe” and the “Naturaliste” – set sail from the harbor of Le Havre, France. Under the command of Captain Nicolas Baudin (1754-1803) geographers, astronomers, artists, naturalists, zoologists, botanists, and 2 mineralogists – Louis Depuch (1774-1803) and Charles Bailly (1777-1844) – were instructed to explore, map and eventually claim for France new territories of this new world. In the last moment also the young zoologist, and trained paleontologist, Francois Auguste Peron (1775-1810) joined the expedition.

The geological observations made by Depuch (died during the expedition) are known from various reports send to Baudin. Bailly will publish some notes after his return to France and Peron included his research in the official report of the expedition.

In May 27, 1801 the bare land of Cape Leeuwin was in sight and the naturalists went on land along the Wonnerup Inlet, where they collected the first specimens of Australian animals, plants and rocks.

 

Fig.1. The “Baudin” – expedition, route drawn on Louis de Freycinet´s (1779-1842) “Carte générale de la Nouvelle Hollande”, published in 1811 as part of the results of the 1800-1804 expedition.

A storm forced the men to remain on land for several days and one man died during a failed attempt to reach the ships (during the entire expedition 32 men died, 13% of the crew, a surprising low percentage considering the period). The storm separated the two ships, the “Naturaliste” proceeded to the island of Timor, a Dutch colony at the time, where the crew fell ill with Malaria and other tropical diseases. The “Geographe” approached in November 1801 the island of Tasmania, where the expedition will stay for three months.
April 1802 the “Geographe” meet the British vessel “Investigator“. The expedition of the “Investigator” will map large parts of South-Australia and prove that Australia is one large continent, not two islands separated by a sea strait, as some geographers assumed. This was a disappointing discovery for captain Baudin, as there was no apparent geographic separation between the territories already claimed by British explorers, the entire continent had to be considered of British domain.

Captain Baudin, the crew and the naturalists could now only hope to gain some fame with the scientific results of the expedition...

The geologists Depuch and Bailly used a rock classification scheme, developed by the famous French geologist Déodat de Dolomieu, with four categories. They recognized primary rocks, such as granite; secondary rocks, such as stratified sandstone and limestone; alluvium (recent deposits) and volcanic rocks, such as basalt. The presence of these rocks in Australia was an important discovery, it proved that the classification scheme developed in Europe could be applied worldwide.

 

Fig.2. Charles-Alexandre Lesueur´s and Nicolas-Martin Petit´s depiction of Van-Diemen´s-Land for the “Voyage de decouvertes aux Terres Australes“. The two young men – unskilled workers at the beginning of the expedition -  were invited by Baudin to illustrate the logbook  -  both will become the most skilled artists for animal- and plantlife of the time. The granitic rocks found on the island of Tasmania convinced Peron and the other geologists that the most ancient – the primary – rock was Granite, forming the basement of all continents.

Paleontologist Peron noted along the west coast of Australia horizontal sand- and limestone layers (the Tamala-Limestone) and concluded, based on similarities to recent sediments, that these layers were deposited along an ancient beach, implying substantial variations in the sea level during geologic time:

“One of the greatest achievements of modern geology research and also one of its most indisputable, is the certain knowledge that, in the past, the level of the sea was higher than at the present time. At almost all places in the old and the new world is the proof of this phenomenon as numerous as it is evident. Only in les Terres australes was this still to be ascertained as, by virtue of its immense areal extent, it could have proved to be an important exception to the universality of the former domination of the ocean over the land.” 

(PERON & FREYCINET 1816)

Unfortunately the return to France will be disappointing for Peron. Captain Baudin dies on the island of Timor and French authorities will show little interest in the 220.000 samples of animals, plants and rocks, the 73 living animals, 3 kangaroos, 2 emus and 3 wombats brought back to Europe.

Peron publish his report “Voyage de decouvertes aux Terres Australes” only in  1807, after a long struggle for money and dies just three years later, before the completion of the second volume. However the sea shells collected during the expedition will be studied by an important French naturalist – Jean-Baptiste de Lamarck. In 1804 Lamarck publishes his theory about the transmutation of species, based in part of the observation that the fossil shells found in the sediments of France are similar, but not identical, to shells of living molluscs collected in Australia.

 

Fig.3. Peron discovers on the shores of Tasmania a living clam with a peculiar triangular shape – Trigonia antarctica – a genus of bivalve known only from fossils found in the sediments of the basin of Paris. He notes the similarities of this living specimen with fossil specimens – an important step to consider a relationship between fossil and extant species. Image of Trigonia sp. from Cretaceous sediments of Bavaria.

Unfortunately for Lamarck – and the naturalists of the Baudin expedition – he mixed his careful observations with wild speculations. Lamarck noted variations of organisms in time, however he could not explain why such variations occur or why certain organisms went extinct or survived – apart invoking a final cause and implying a sort of supernatural scheme. Geologist Charles Darwin will later regard Lamarck’s work as “useless“...

Fig.4. Geological map by Jules Grange, published in 1850, surprisingly little was known of the geology of Australia until the 20th century.

Bibliography:

GLAUBRECHT, M. & MERMET, G. (2007): Josephines Emu oder Die Geschichte einer vergessenen Expedition. GEO Nr.6/2007: 98-122
MAYER, W. (2008): Early geological investigations of the Pleistocene Tamala Limestone, Western Australia. from GRAPES, R.H.; OLDROYD, D. & GRIGELIS, A. (eds) History of Geomorphology and Quaternary Geology. Geological Society, London, Special Publications 301: 279-293
MAYER, W. (2009): The Geological Work of the Baudin Expedition in Australia (1801-1803): The Mineralogists, the Discoveries and the Legacy. Earth Sciences History Vol.28 (2): 293-324
RUDWICK, M.J.S. (2005): Bursting the limits of time – The reconstruction of Geohistory in the Age of Revolution. The University of Chicago Press, Chicago, London: 708

Invasion of the European Dinosaurs!! Part I: ca. 1800-1900

Fig.1. Archaeopteryx  

The fossil gallery at the recent Munich Show 2011 was dedicated to the "European Dinosaurs" - a good overview of some of the historic fossils (with the classics from Victorian Britain and Germany), but also special apparitions of the newest discoveries from the Mesozoic of the European continent.

Dinosaurs have a long tradition in Europe - the first (as such) recognized "terrible lizards" came from England: it was in 1824 that there Reverend William Buckland described the lower jaw of Megalosaurus. 

Fig.2. The jaw of Megalosaurus as published in Buckland´s "Notice on the Megalosaurus or great Fossil Lizard of Stonesfield" (1824).

Fig.3. Isolated tooth, Megalosaurus bucklandi, from the Jurassic Stonesfield-Formation (Oxfordshire), found previously of 1882.

But already in 1677 the English historian Robert Plot (1640-1696) describes in his "The natural history of Oxfordshire" a gigantic bone (today lost), found presumably in a quarry at Chipping Norton (also Oxfordshire), as the bone of an elephant of Roman age.
It seems plausible that in the next centuries ulterior bones were discovered, however only with the advent of comparative anatomy (promoted by the French naturalist Georges Cuvier) it became clear what these bones could be - the remains of large reptiles, however quite different to all living animals. After the description of Megalosaurus soon followed Iguanodon (1825), Hyaeosaurus (1833), Thecodontosaurus (1836) and Cetiosaurus (1836).

The first non-british dinosaur came from the Triassic sediments of Southern Germany, described by the German palaeontologist Hermann von Meyer as Plateosaurus in 1837. 

 Fig.5. Plateosaurus.

Streptospondylus and Poekilopleuron were described in 1832 and respectively in 1838 from Jurassic sediments in France. Archaeopteryx was first described (again by von Meyer) in 1861 based on a single feather, only later an almost complete specimen started an intense debate about the evolutionary connection between dinosaurs and birds. In the same year a distant cousin of Archaeopteryx was described by Andreas Wagner as a sort of very strange lizard: Compsognathus longipes.

Fig.6. The first fossil of Compsognathus, discovered in 1858 by physicist and fossil collector Joseph Oberndorfer.

The British anatomist Thomas Henry Huxley recognized it as example of one of the first complete dinosaurs and based his very cautionary and speculative hypothesis of a possible "relationship" between reptiles and birds on this species. Huxley described in 1868 another small dinosaur species, but this time a herbivore: Hypsilophodon.
In February 1878 miners discovered a bone bed of Iguanodon, the almost complete skeletons enabled palaeontologist Louis Dollo (1857-1931) to reconstruct a large, biped and herbivorous animal. 

Fig.7. Hypsilophodon foxii, Wealden (Lower Cretaceous), collected previously 1882.

Bibliography:

RAUHUT, O.W.M. (2011): Kontinent der Dinosaurier - Europa. Mineralientage München - Messekatalog: 132-146

In Megalonyx We Trust: Jefferson's patriotic monsters

During the transition of the 18th to the 19th century earth sciences experienced a major revolution - the principles of the modern identification of rocks was introduced and sediments subdivided by the content of embedded fossils. Animals of the past apparently differed from modern ones in their abundance and in their diversity (so they could be used to subdivide the stratigraphic column) and some organisms were completely unknown to modern scholars. These observations led to a major problem: if these organisms are today unknown, are they surviving in remote regions of the globe and yet not discovered?
Classic monsters, like sea serpents along the shores of North America, the giant kraken along the shores of Africa and even sirens in the sea surrounding the United Kingdom, were spotted and depicted in books for centuries (and still today), but now naturalists responded with scepticism and reluctance to these stories - reports coming from America were soon considered as "Yankee Humbug" by European scholars.

In 1812 Georges Cuvier proclaimed that there was little hope to discover new species of large tetrapods and regarding the efforts of explorers to track down mythical animals he noted:

"…we hope that nobody thinks to search them for real, it would be like searching the animals of Daniel or the beasts of the apocalypse. Let us not even search for the mythical animals of the Persians, results of an even greater imagination."

In 1796 the third president of the United States, also president of the American Philosophical Society and naturalist Thomas Jefferson (1743-1826) studied some fossil bones and a giant claw discovered during mining activities in a cave.
March 10, 1797 he presented the results to the Philosophical Society under the title "A Memoir on the Discovery of Certain Bones of a Quadruped of the Clawed Kind in the Western Parts of Virginia" and concluded that these remains belong to a giant felid " three times as large as the lion" which he named "Megalonyx" (great claw).

Fig.1. Engraving of the bones of the foot, toe, and claw of Megalonyx, as published in a paper by Caspar Wistar "A description of the Bones deposited by the President, in the Museum of the Society, and represented in the annexed plates." (1799). Jefferson's Megalonyx paper, which had no illustrations of the bones, was published in the same volume of American Philosophical Society Transactions.

Jefferson, in accordance to the naturalistic knowledge of the time, believed that in nature no species could became extinct, so he continued in his report:

"In the present interior of our continent there is surely space and range enough for elephants and lions, if in that climate they could subsist; and for the mammoth and megalonyxes who may subsist there. Our entire ignorance of the immense country to the West and North-West, and of its contents, does not authorise us so say what is does not contain."

Jefferson based this conclusion in part on anecdotes of woodsmen being terrorized by a large cat-like animal in the wilderness and the presumed representations of lions in Indian rock paintings (possibly the American lion Panthera atrox ?).

However the most important argument for Jefferson was a theological one: if a species can become extinct in a perfect divine creation such a creation can't possibly be so perfect all along, the continuous loss of species would inevitable lead to the end of this imperfect creation.

"The movements of nature are in a never ending circle. The animal species which has once been put into a train of motion, is still probably moving in that train. For if one link in nature's chain might be lost, another and another might be lost, till this whole system of things should be evanish by piece-meal; a conclusion not warranted by the local disappearance of one or two species of animals, and opposed by the thousands and thousands of instances of the renovating power constantly exercised by nature for the reproduction of all her subjects, animal, vegetable, and mineral."

Fig.2. Sketch of the so called "Madrid skeleton" sent to Jefferson by tradesman William Carmichael in 1789. A large skeleton was found near Buenos Aires, in his letter Carmichael notes "I also inclose…a discription of the Skeleton of an Animal discovered lately in Spanish America. I supposed these to be objects of Curiosity to you,…" Jefferson recognized that the bones and claw he had attributed to his large cat Megalonyx were comparable to these of this animal, described in 1796 by Cuvier as Megatherium.
Jefferson also collected all sorts of information about large mammals and bones to support his view of the new continent as populated with fascinating animals as the old continent and rest of the world.

Jefferson also had some political motives to support the existence of large and ferocious animals in the U.S.
In his works the eminent France naturalist Georges-Louis Leclerc, Comte de Buffon (1707-1788) proposed a theory to explain the worldwide distribution of animal species: from environmental optimal centres species would spread all over the globe, however degenerating in areas with less favourable climate or environment - and according to Buffon the fauna of America was an perfect example of such a degenerated European and African fauna.
This worldview not only offended Jefferson's personal feelings, but also seriously damaged the reputation of the young United States of America. The U.S. needed the political and financial support of France during the Revolutionary Wars (1775-1783), Buffon was however popularizing the perception that "America is an excessively cold and humid continent where big animals cannot survive, domestic animals become scrawny, and men become stupid and lose their sexual vigor" (ROWLAND 2009)

In spring 1785 Jefferson published anonymous his "Notes on the State of Virginia", where he discussed naturalistic and also political facts of this state. In various lists he compared the mammals of the new continent to the mammals of the old continent, concluding that the body mass and diversity of American animals was far superior then envisaged by Buffon. He also reaffirmed his view on the impossibility of extinction:

"The bones of the Mammoth which have been found in America, are as large as those found in the old world. It may be asked, why I insert the Mammoth, as if it still existed? I ask in return, why I should omit it, as if it did not exist?
Such is the economy of nature, that no instance can be produced of her having permitted any one race of her animals to become extinct; of her having formed any link in her great work so weak as to be broken. To add to this, the traditionary testimony of the Indians, that this animal still exists in the northern and western parts of America, would be adding the light of a taper to that of the meridian sun. Those parts still remain in their aboriginal state, unexplored and undisturbed by us, or by others for us. He may as well exist there now, as he did formerly where we find his bones."

In 1803 Jefferson organized the famous Lewis and Clark expedition; apart political important tasks, like the geographical exploration of Louisiana and the search for a navigable passage to the Pacific, this expedition should also dig for fossils and search for the supposed unknown large tetrapods of North America.

Jefferson in his lifetime never really embraced the theory of extinction, probably as a results of personal religious beliefs and political agenda - only in the mid 19th century extinction will become a scientific fact.

Bibliography:

ROWLAND, S.M. (2009): Thomas Jefferson, extinction, and the evolving view of Earth history in the late eighteenth and early nineteenth centuries. In ROSENBERG, G.D., ed., The Revolution in Geology from the Renaissance to the Enlightenment: Geological Society of America Memoir 203: 225-246

Online Resources:

MURPHY, D.C. (): Fossils and Extinction. The Academy of Natural Sciences. (Accessed 15.08.2011)
MURPHY, D.C. (): Discovering The Great Claw: Part 1 - The Giant Cat. The Academy of Natural Sciences. (Accessed 15.08.2011)

8, July 1836: Darwin on St Helena

The HMS Beagle, with on board the amateur naturalist Charles Darwin, arrived at the remote island of St Helena on July 8, 1836, where it stayed until noon of July 14, afterwards proceeding its journey back to the United Kingdom and setting sails to the nearby island of Ascension.
Darwin used these five days to explore the geology of the island and hired an elderly man as a guide. Since Van Diemen´s Land Darwin's written notes and observations had become more hasty and fragmentary - as a combination of the short stops by the Beagle on the single islands and maybe a bit of homesickness, nevertheless Darwin dedicated later one of his notebooks, written down in September to December 1938, to the island, the "St Helena Model", where he on 15 pages noted observations and thoughts on the general island geology (and also troubles with the laundry).
As already on the island of St. Jago Darwin noted various geological evidence that the island had risen from the sea in an outcrop of basaltic rocks:

"The successive sheets are either closely united together, or are separated from each other by beds of scoriaceous rock and of laminate tuff, frequently containing well rounded fragments. The interstices of these beds are filled with gypsum and salt; the gypsum also, sometimes occurring in thin layers. From the large quantity of these two substances, from the presence of rounded pebbles in the tuff, and from the abundant amygdaloids, I cannot doubt that these basal volcanic strata flowed beneath the sea."
DARWIN (1844) "Geological Observations on the volcanic islands and parts of South America visited during the Voyage of H.M.S. "Beagle"." 75-76

Fig.1. A section trough the coastline of St Helena by the hands of Charles Darwin (dated 15 September 1838), from CHANCELLOR 1990.

At the time the origin of volcanoes as mountains was under scrutiny, one model - proposed by the eminent German geologist Leopold von Buch (1774-1835) - stated that volcanoes form like a bubble: first geologic forces upraise the ground and form the mountain, the summit collapses, forming the steep crater walls, finally the magma can spout trough the surface, causing an eruption. Lava flows or ash layers where therefore a secondary feature of volcanoes, not the "construction material" of the volcanic complex. This "crater of elevation" hypothesis was very popular at the time and supported by most European geologists. Two French geologists, Armand Dufresnoy (1792-1857) and Léonce Elie de Beaumont (1798-1874), tried even to prove mathematically that continuous lava flows can form only on surfaces with an inclination less than 6°, according to their calculations on steeper surface a flow start to disintegrate, and as most observed lava flows were however steeper, this observations could only be explained by the surface of the volcano steepen over time.

Fig.2. Topographic map of the Canary Island published by von Buch in 1814 in his book "Description physique des lles Canaries, suivie dúne indication des principaux volcans du globe." Von Buch assumed that the radial valleys, descending from the central summit, are fissures caused by the inflation and uprising mountain - in fact these valleys are formed by the erosion of the volcanic rocks.

Darwin did not share entirely this vision of uprising volcanoes; in part the model proposed very fast rates of elevation and Darwin was more inclined to follow the gradual geology as proposed by Charles Lyell - Lyell himself refused the "crater of elevation" hypothesis outright.
Darwin addressed the problem only superficially: he used the observations on St Helena to formulate an intermediate hypothesis, volcanoes rise by slow, gradual and episodic events, he also suggested that more research was necessary to map and determinate the inclination of lava flows.

In 1850 Lyell demonstrated on a lava flow of Mount Etna that the lava solidified on a slope inclined by 35° - the "crater of elevation" hypothesis had lost one of its most important arguments and Darwin left behind the hypothesis of inflating volcanoes.

Bibliography:

CHANCELLOR, G.R. (1990): Charles Darwin's St Helena Model Notebook. Bull. Br .Mus. Nat. Hist. 18(2): 203-228
HERBERT, S. (2005): Charles Darwin, Geologist. Cornell University Press: 485
KRAFFT, M. (1993): I vulcani - il fuoco della terra. Universale Electa-Gallimard: 191

May 8, 1902: La Pelée

"My Dear Sister: This morning the whole population of the city is on the alert and every eye is directed toward Mont Pelee, an extinct volcano. Everybody is afraid that the volcano has taken into its heart to burst forth and destroy the whole island."

Mrs. Thomas T. Prentis, wife of the United States Consul at St. Pierre, to her sister in Melrose (Boston). After May 8, rescuers would find the charred corpses of both the consul and his wife, sitting in chairs in front of a window that faced Pelée. The bodies of their children would never be found.

Despite recognized as volcano, Mount Pelée, - the bald headed mountain - owning possibly its name to the devastation of an eruption occurred in 1635 before the European colonization, on the island of Martinique was considered extinct since an eruption in 1767 that killed more than 16.000 people living on its slope. In 1856 the mountain however gave signs of activity with minor eruptions of steam and single mudflows descending the slopes, however the rich city of St. Pierre was not affected.

Fig.1. A relief map of Mount Pelée showing the area affected by the eruptions of 8 May and 3 August, 1902, after Lacrox 1904. Note on the summit of the volcano two depressions - L´Etang Sec, a temporary lake, and the Lac de Palmistes.

In April 1902 the old father - as the mountain was referred by the locals- awoke again with violent explosions and on the summit a depression became filed with boiling water - the L'Etang Sec (the dry lake). End of April ash fall on St. Pierre were reported by the local newspaper "Les Colonies":

"The rain of ashes never ceases. At about half-past nine the sun shone forth timidly. The passing of carriages in the streets is no longer heard. The wheels are muffled [in the ashes]. Puffs of wind sweep the ashes from the roofs and awnings, and blow them into rooms of which the windows have imprudently been left open."

The population of St. Pierre became anxious, many of the residents left the city, but they became immediately replaced by refugees from the area surrounding the volcano and many non-residents coming to town for the election of the new island governor on May 10.

On May 5, heavy rain occurred and the dam holding back the boiling water of L´Etang Sec collapsed, a gigantic mudflow rushed down the slopes of Pelée and buried completely a sugar mill on the base of the mountain, 150 people were killed, the waves generated in the sea reached even the harbour of St. Pierre - people begun to panic.
In an effort to tranquillize the public and hold the voters in the city the French governor appointed a commission to investigate the danger from the volcano. "Les Colonies" stated:

"[Professor Landes of the Lycée concludes that] Mt. Pelée presents no more danger to the inhabitants of Saint Pierre than does Vesuvius to those of Naples."

Fig. 2. The newspaper "Les Colonies" May 7, 1902 with the statement that La Pelée "presents no danger", 24 hours later all journalists and editor were dead.

Ironically the Italian Marino Leboffe, Capitan of the freighter Orsolina anchoring in the harbour, complained on May 2, to the local authorities:

"I know nothing about Mount Pelée, but if Vesuvius were looking the way your volcano looks this morning, I'd get out of Naples."

On May 7, the volcano La Soufriére on the island of St. Vincent, 145 km distant, exploded, people hoped that the violent eruption released enough pressure of the earth to prevent the eruption of old father, the residents settled down.

May 8, would became a sunny day, a column of steam was rising above the old father, but otherwise the activity of the volcano seemed unchanged.
At 7:50 in the morning the Pelée blew itself to pieces. For hours after the four explosions the city burned, and for days it was unapproachable by the great heat emanating from the ruins.
Estimated 28.000 to 40.000 people died, only three survivors were reported. The young shoemaker Léon Compère-Léandre (1874-1936) escaped from the border of St. Pierre into the village of Fonds-Saint-Denis, the girl Havivra Da Ifrile tried to escape to a cave near the coast and was washed onto the sea, where she was rescued days later. To Da Ifrile we owe one or the rare eyewitnesses accounts of the eruption:

"But before I got there, I looked back-and the whole side of the mountain which was near the town seemed to open and boil down on the screaming people. I was burned a good deal by the stones and ashes that came flying about the boat, but I got to the cave,…"

One of the most well-know survivor was the 25-year-old stevedore Louis-Auguste Cyparis (1875-1929), who survived in his small prison cell and became known as the "Samson of St. Pierre" in the Barnum & Bailey Circus where he worked and told his story after his rescue.

Fig.3. The "Samson of St. Pierre".

Fig.4. and 5. Photograph of St. Pierre, Martinique, in the 19th century long before the eruption, and photograph by Angelo Heilprin of St. Pierre after the eruption of Mount Pelée on May 8, 1902. The monstrous blast and subsequent pyroclastic flows wiped out the entire city, only four locals survived this day of the final eruption, one was staying outside the city, the other three escaped or survived by mere chance.

On May 20, Pelée exploded again investing the ruins of the city and killing 2.000 rescuers, engineers, and mariners bringing relief supplies to the island.

The devastation experienced in St. Pierre was unexplainable at the time when volcanology was still regarded only as a minor branch of geology. However May 21, the first scientists arrived to the island to study the volcano. They noted the signs of an unknown and deadly phenomenon - the "nueé ardente" or pyroclastic flows, a dense "cloud" of ash, hot gases, fragments of magma and superheated steam moving downhill generated by the collapse of volcanic domes.

Fig.6. Pyroclastic flows December 16, 1902 at La Pelée documented by Lacroix 1904. Lacroux will propose the first modern classification of volcanic activity - one explosive type will be known as Pelean type.

This particular kind of eruption was first studied at Pelée and gave since then its name to this kind of volcanic activity: the Pelean type is common on convergent plate margins and characterized by its explosive character and dangerous pyroclastic density currents.

Fig.7. From October 1902 to September 1903 (when it collapsed) a 300m high obelisk like dome of lava grow from the crater of L´Etang Sec, the American scientist Angel Heilprin noted that is seemed as if ". . . nature's monument dedicated to the 30,000 dead who lay in the silent city below."

Bibliography:

DAVIS, L. (2008): Natural Disasters. Facts on File Sience Library. Infobase Publishing: 464
HEILPRIN, A.(1903): Mont Pelée and the Tragedy of Martinique. J.B. Lippincott Company, Philadelphia and London: 335.
LACROIX, A. (1904) : La Montagne Pelée et ses éruptions. Masson et Cie, Paris.
MORRIS, C. (2006): The San Francisco Calamity by Earthquake and Fire. Librivox.

Online Resources:

ALEAN, J. ; CARNIEL, R. & FULLE, M. (15.05.2007): La Montagne Pelée und Saint Pierre - September 2005. (Accessed 08.05.2011)
Cerimes (01.01.1974): Eruption de la montagne Pelée - 8 mai 1902. (Accessed 08.05.2011)

The Eruption of the Revolutionary Volcano

The subversions ongoing in the North African countries of Tunisia, Egypt and Libya have inspired a cartoon found by Malcolm and presented on his blog Pawn of the Pumice Castle - the depiction, aside from the ludicrous concept of geology, compares the rage of the people with a sort of magma chamber soon to feed a volcanic eruption (in Egypt already successful).

The use of forces of nature as metaphor has a long tradition, especially phenomena as fire, floods or storms were often associated to negative historic events like war, invasion or plagues.
In the 18th century the European revolutions to overthrow kings and dictators, especially the French revolution of 1789-1799, changed this negative significance, now fast occurring social changes were like disasters with a positive aftermath - the old becomes destroyed to make place for the new. It was still under the impression left by the great earthquake of Lisbon in 1755 that the metaphors of earthquake arouse - a local event hat could affect an entire continent.

"Many parts of Europe are in obvious disorder. In many others there is a dull rumble coming from underground, a faint movement is felt that threatens the political world like a general earthquake."
Edmund Blurke (Irish philosopher, 1729-1797)

The picture of the volcano as positive symbol of insurrection against social injustice needed more time to become popular. Despite travel accounts and pamphlets, an erupting volcano was a rare event in Central Europe and mostly unknown to the larger public. In contrasts the popular tumult in Naples of 1647 was promptly compared to a volcanic eruption by the contemporary chronicles.

The use in the French language of the general term "éruption" during the French Revolution, meaning all kinds of release, from buds releasing their flower to realising own feelings or anger, became connected with the general comparison of the revolution to a purifying fire - it was then a short step to use the volcano to depict the enraged population:

"In the Royal Palace the most violent invocations followed with tremendous speed, the most violent orators jumped on the tables, inflamed the minds of their audience, which assembled around them, then to spread into the city like the burning lava of a volcano."
"Histoire de la Revolution de 1789 et de l´Establissement d´une Constitution en France." (1790)

Fig.1. "Third Eruption of the Revolutionary Volcano" (original caption "third eruption of the volcano of 1789, to take place before the end of the world, which will shake all thrones, and overturn a horde of monarchies") by Auguste Desperret (1804-65), lithography published in the magazine "La Caricature" of June 1833. Only after 1795 depictions of eruptions became commonly associated with social revolution (see also the volcanism blog for a further analysis of the image).

Bibliography:

THÜSEN, J.v.d. (2008) : Schönheit und Schrecken der Vulkane - Zur Kulturgeschichte des Vulkanismus. Wissenschaftliche Buchgesellschaft, Darmstadt: 239

Outburst flood from Glacier de Tete Rousse: A past and future threat

To protect the 3.000 inhabitants of the France village of Saint-Gervais–Le Fayet from a possible glacier outburst, the authorities have decided to drill into and install pumps on the Glacier de Tête-Rousse (Mont Blanc Massif), where a larger volume (65.000 cubic meters) of stagnant water is presumed. A supraglacial lake containing estimated 25.000 cubic meters water was discovered during this March, the authorities now fear that the water could be released in a sudden outburst when the surrounding icewalls collapse or the water excavates an outlet. In the course of this week the base camp at 3.200m a.s.l will be prepared, the drilling and installing of the pumps will presumably be concluded until October, before the onset of the winter.

Meanwhile the residents of the villages were warned of the possible danger and a evacuation plan is in elaboration.
The precautions are not entirely unfounded; in the night between July 11. and 12., 1892 the village of Saint-Gervais was severely damaged and 175 peoples killed by a 200.000 cubic meters outburst coming from the Tête-Rousse Glacier.
In the Alps, outburst floods from intraglacial cavities are not rare but generally lead to only small discharges and debris flows causing little or no damage. The outburst flood from Tête-Rousse was, however, one of the deadliest disasters ever caused by a glacier.

Before 1878, in a period with increased rate of ablation, a supraglacial lake formed in the centre of the glacier, this lake subsequently became covered by ice and snow.
The collapse of the glacier tongue in 1892 finally released the accumulated water, a large cavity 40m in diameter and 20m high containing estimated 20.000 cubic meters water at the glacier terminus remained as testimony. From this lower cavity, an 85m long intraglacial conduit led to the upper cavity (the former lake) with an additional volume of 80.000 cubic meters.

Fig. 1. The lower cavity at the terminus of the glacier, note epeople for scale. A part of the snout has been torn from the glacier. Photograph by H. PELLOUX, September 1892, figure from VINCENT et al. 2010.

Fig. 2. The upper cavity (former supraglacial lake) at the centre of the glacier. Photograph by M. KUSS, 13 August 1893, figure from VINCENT et al. 2010.

Fig. 3. Longitudinal section of the tongue, sketch from VALLOT and others (1892), figure from VINCENT et al. 2010.

After the catastrophe a monitoring program was initialized and in 1898-1899 a horizontal tunnel drilled to prevent water accumulation inside the glacier. In 1901, a 50m long and 40m deep crevasse became filled with water, so until 1904 a new tunnel was constructed, and 22.000 cubic meter water drained. This tunnel still exists and is supposed to prevent water accumulation close to the bedrock of the glacier.

Fig. 4. Map of surface and bedrock topography in 2007. The locations of the upper cavity and lower cavity (green dashed curve) and the excavated tunnels 81899 and 1904) are shown.

References:

VINCENT, C.; GARAMBOIS, S.; THIBERT, E; LEFEBVRE, E.; LeMEUR, E. & SIX, D. (2010): Origin of the outburst flood from Glacier de Tète Rousse in 1892 (Mont Blanc area, France). Journal of Glaciology, Vol. 56(198): 688 - 698

Landslides in the Alps: Introduction and History of research

Landslide and rockfall events belong to a class of geological phenomena which occur rapidly, contradicting our believes of geology occurring only on large time spans, and for this and the often catastrophic results they are widely recognized even by non geologists. Especially native people in mountain ranges, like the Alps, know rockfall events and their aftermath.

Fig.1. Landslides in the Alps after ABELE 1974 with mentioned sites.

Myths in the Alps often refer to landslides as punishment for greedy people, the mountains punish the village or man who denied help to others by entombing it alive. In historic times documented landslides in the Alps are reported from the Roman Tauredunum (exact location unknown, but presumably Wallis, Swiss) and from the Lavini di Marco (Italy) in 833 A.D., Mont Granier (France) in 1246 A.D., Dobratsch (Austria) in 1348 and Plurs (Swiss) in 1618, to mention some examples.

Fig.2. A strong precipitation event caused in 1618 the landslide that destroyed the Swiss city of Plurs (Cantone Graubünden). Figure from BEHRINGER 2007.

The first scientific considerations on landslides were published by BERTRAND in 1757, who studied especially the relationship between landslides and earthquakes, and BEAUMONT in 1806, who in a description of the region of Savoy (France-Italy) includes also landslides and their deposits. The landslide catastrophe of Goldau in 1806, where an entire village was destroyed and 457 people killed, was described in detail by ZAY (1806).

Fig.3. The Goldau rock slide on September 2nd. 1806 at the Rossberg, Cantone Schwyz, Switzerland. Painting by H. Keller 1806. Figure from THURO et al. 2005.

In 1807 ESCHER completes a first inclusive list of historic landslides in Swiss. In his "Geschichte der durch Überlieferungen nachgewiesenen natürlichen Veränderungen der Erdoberfläche" (History of lore on the proven natural variations of Earth's surface) HOFF (1834) extens the list to the entire Alps.

In the Eastern Alps the study of landslide morphologies is carried out some years later, with pioneering work by SCHAUBACH (1845-1847) and BALTZER (1847-1875 and 1880).
The catastrophe of Elm in 1881, where a landslide was triggered by unsafe quarrying of schist and caused the death of 115 peoples, enforced the scientific study of landslide in relationship to men's activity and safety, an important contribution in these times is appropriately denominated "Bergsturz und Menschenleben" (Landslide and human life) (HEIM 1932).

The first half of the 20th century sees the compilation of a register by various authors of landslides on a regional scale, most time for single mountain groups in the Alps. But in the same period the interests of geologists and engineers shifts to slow mass movements, like slope deformations, better studied and understand at these times.

This situation , like before, changes with a human induced catastrophe in 1963. The tragedy of the landslide of the Vajont, resulting in more than 2000 victims, shifts back the interest to the research on rock mechanics and fast occurring mass movements.
One of the more recent and classic works important for the alpine geology is the work by ABELE 1974 "Bergstürze in den Alpen" (Landslides* in the Alps).

All the mentioned publications are prevalent of descriptive character, mapping the extent of landslide deposits, characterising their morphology and their relationship to other geomorphologic features, but only the last years have experienced a increase of our understanding of the mechanism of landslides-initiation and movement. With the development of geophysical survey methods it is possible to look into landslide deposits, with new dating methods it is possible to date such deposits, and interfere "periods" of landslide activity and possible triggers occurring at these times, with the advancement of computer models large landslide deposits can be simulated and compared to features observed in the field.

References:

ABELE G. (1974): Bergstürze in den Alpen. Wissenschaftl. Alpenvereinshefte Nr. 25: 230
AMANTI, M. & CESI, C. (2004): Italian Alpine Landslides. Field Trip guide Book - PostCongress P05, ITALIA 2004 32nd International Geological Congress, Florence - Italy August 20-28, 2004: 65
BALTZER, A. (1874/1875): Über die Bergstürze in den Alpen. Jahrbuch des Schweizer Alpenclub, Jg.10: 409-456
BALTZER, A. (1875): Über einen neuen Felssturz am Roßberg, nebst einigen allgemeinen Bemerkungen über derartige Erscheinungen in den Alpen. Neues Jahrbuch f. Min. Geol. u. Pal.: 15-26
BALTZER, A. (1880): Über Bergstürze. Neues Jahrbuch f. Min. Geol. u. Pal.: 197-199
BEAUMONT, A. (1806): Description des Alpes Grecques et Cottiennes ou tableau historique et statistique de la Savoie. Vol.2.(2), Paris: 659
BEHRINGER, W. (2010): A Cultural History of Climate. Polity Press: 295
BERTRAND, M.E. (1757): Mèmoires historiquè et physiques sur les tremblements de terre. la Haye: 326
ESCHER, H.C. (1807): Über Bergstürze in der Schweiz. Neujahrsblatt d. Naturf. Ges., Zürich: 1-8
HEIM, A. (1932): Bergsturz und Menschenleben. Beiblatt zur Vierteljahrsschrift der Naturforschenden Gesellschaft in Zürich, Nr. 77, Zürich: 218
HOFF, K.E.A.v. (1834): Geschichte der durch Überlieferung nachgewiesenen natürlichen Veränderungen der Erdoberfläche. III Theil, Gotha: 511
SCHAUBACH, A. (1845-47): Die Deutschen Alpen. Jena, Teil I-V
THURO, K., BERNER, C. & EBERHARDT, E. (2005): Der Bergsturz von Goldau 1806 - Versagensmechanismen in wechsellagernden Konglomeraten und Mergeln: 303-308. In: Moser, M. (ed): Veröffentlichungen von der 15. Tagung Ingenieurgeologie, 6-9. April 2005, Erlangen: 482
ZAY, K. (1807): Goldau und seine Gegend, wie sie war und wie sie geworden. Zürich: 390

*The German term Bergsturz (mountain fall) is not completely synonymous to the English term landslide - it is defined as movements of rocks or debris at high speed (that can include falling and/or gliding) with a volume exceeding 1 million cubicmeters and covering an area of more than 0,1 km2.

History of Paleomammology: Cuvier's opossum

"Every life form is to be considered as a unit, a unified and closed system, in which single parts correspond each to other and work together: A specific action invokes a specific reaction. No part may change if not other parts also change. Hence the result, that if we observe a single part, we can deduct the other ones."

On the first of February 1796 the French naturalist Cuvier held a presentation about known modern and fossil elephants. He studied many bones found in Europe, Siberia, America, Africa and India, and as an important result he finally described a new fossil species, the first elephant - Elephas primigenius.
Cuvier is convinced that the bones came from an extinct creature of distant past, not, as some other naturalists claim, represent the remains of the war-elephants of Hannibal in 218 B.C.

Cuvier is today considered the founder of comparative anatomy and palaeontology; with only some parts of the skeleton it is possible to reconstruct the whole animal and its behaviour.
"If the guts of an animal are specialized to digest meat, the jaw and teeth must be suitable to swallow the prey, and the claws have to catch and tear apart the flesh. Its system of locomotion must be suitable to hunt prey, and its senses must register prey from the distance. Nature must given it a brain and the instinct to entrap the victim."

He dedicated many publications to this approach: His researches on modern mammals comprise the osteology of the Indian Rhinoceros (Rhinoceros indicus = R. unicornis), of the tapir and Hippopotamus, sloth, manatee and many others.
He examined the remains of the fossil giant sloth, Megalonyx of Megatherium, the cave hyena, the Palaeotherium, as well as studying and describing various extinct species of rhinoceros, hippopotamus, elephant, manatee, seal and cave bear.
He examined intensively the remains of mammals found in the layers of Montmartre, an area with quarries in the periphery of Paris, describing the fossil marsupial-like Didelphys gypsorum - denominated for its resemblance to the American opossum as Opossum of Montmartre.

Fig.1. Didelphys gypsorum as published in "Recherches sur les fossiles de ossements quadrupedes" (1812).

"The imprint is weak, it should be observed very closely to recognize something. But its posses an immense value, this are the footprints of an animal, from which we would otherwise have no trace."
The fossil is well preserved, and observing the characters of the jaw and teeth, Cuvier recognizes that the fossil is related to the modern opossum. Following his own rules, he predicts that along with the skeleton there must be found two small bones, that in modern marsupials sustain the poach. It was a triumph for Cuvier's method when the bones were finally discovered under the scrutiny of invited colleagues.*

The summary results of the geological and paleontological studies of Cuvier were finally made public in 1812 with two separate works, the first is the celebrated "Recherches sur les fossiles de ossements quadrupedes", and the second is the "Discours sur les revolutions de la surface du globe."

Fig.2. Stratigraphic profile published by Cuvier and Brongniart in their work "Essai minéraligique sur les environs de Paris" (1st edition 1808), figure from here, for the stratotype see here.

Cuvier, as previously Buffon, claims that the fossils show an alternation of different faunas during the geological history of the earth, various "revolutions" have changed the face of the earth and species have become extinct and been replaced by new ones.
To support this hypothesis he begins to study and map the stratigraphic successions of the basin of Paris. In collaboration with the young geologist Alexandre Brongniart, after four years of work, in 1808 they publish the "Essai minéraligique sur les environs de Paris" (1st edition 1808), complete with a geological map and a stratigraphic column with seven formations, some of which contain the fossils vertebrates studied by Cuvier (especially the Formation of chalk colored in blue).

The method of comparative anatomy promoted by Cuvier marks the beginning of another aspect in palaeontology - the reconstruction of life appearance of extinct animals by scientists and artists. Using the principles he formulated, Cuvier commissioned the first scientific accurate reconstruction of an extinct mammal. In his book "Recherches sur les fossiles…[]" (1812) were published the reconstruction drawings of two paleomammals of the French Tertiary, Palaeotherium and Anoplotherium.
This simple act is an attempt to create life starting from the skeletons of ancient animals, today such art seems natural, but it was a sensation at that time, for the first time anyone beside the experts could see and admire the creatures of the past. Although Cuvier's drawings are simple sketches that show the animals in outline, they have been widely reproduced over the years.

Fig.3. The reconstructions of Palaeotherium and Anoplotherium as drawn by the artist C.L. Laurillard in Cuvier's " Recherches sur les fossiles…[]" (1812).

*Gideon A. Mantell notes that in some marsupials these bones are only small appendages of cartilage, as an example he cites the case of the opossum with the dog head or Tasmanian hyena - the thylacine. If we would only be in possession of the single bones, and no living specimens - although at the brink of extinction [sic], the animal could not be attributed with certainty to the marsupials (1854, "The Creation of medals" pag.804).

References:

BENTON, M.J.; COOK, E. & HOOKER, J.J. (2005): Mesozoic and Tertiary Fossil Mammals and Birds of Great Britain. Geological Conservation Review Series 32: 215
CUVIER, G. (1825): Discours sur les Révolutions de la surface du Globe, et sur les changemens qu'elles ont produits dans le règne animal. Dufour et d'Ocagne, Paris.
CUVIER, G. (1812): Recherches sur les ossemens fossiles ou l'on rétablit les caractères de plusieurs animaux dont les révolutions du globe ont détruit les espèces. Dufour et d'Ocagne, 4 Vol.. Paris.
CUVIER, G. (1851): Die Erdumwälzungen. deutsch bearbeitet und mit erläuternden Bemerkungen über die neuesten Entdeckungen in der Geologie und Paläontologie versehen. Verlag von Ambr: Abel.