Charlotte Hibbert 1832 Map (first loess map)

Sam.Hibbert's book on the volcanos(sic) of the Eifel region was published in 1832; it contained some interesting discussion on loess and loess deposits (see Loess Letter 67 at www.loessletter.msu.edu).
Attached was a remarkable map, drawn by Charlotte Hibbert- which deserves to be better known and appreciated. We reproduce some parts; what is needed is a full scale republication- the map's full title is:  The volcanic district bounded by the rivers Nette & Bruhl on the Lower Rhine-(for some discussion see Fitzsimmons et al 2019).

Fitzsimmons, K., McLaren, S., Smalley, I.J. 2018.  The first loess maps and related matters; contributions by twenty significant women loess scholars.  Open Geosciences 10, 311-322.

Smalley, I.J. 2019.  Samuel Hibbert in Edinburgh; early studies on loess deposits- connecting Leonard and Lyell.  Quaternary International 502A, 165-172.

 

Loess in Britain XVII: Sir Joseph Prestwich [1812-1896]

Prestwich, J.  1864. (a) Theoretical considerations on the conditions under which the (drift) deposits
containing the remains of extinct mammalia and flint implements were accumulated and their geological age  (b) On the Loess of the valleys of the south of England, and of the Somme and the Seine.  Philosophical Transactions of the Royal Society of London 12, 154,  247-309.

Prestwich wrote on loess and published a significant paper in the Roy.Soc. transactions of 1864. Actually the loess material appeared as part of a two-section paper- which has caused some confusion

There is some bibliographical muddle and this may have prevented him from receiving the loessic credit which is is due.
 

 

Sedgwick & Murchison: early observations on Loess in the Danube valley

Sedgwick, A., Murchison, R.I.  1832.  A sketch of the structure of the eastern Alps, with sections from the newer formations on the northern flanks of the chain, and through the Tertiary deposits of Styria etc. etc.   Transactions of the Geological Society of London (s2) 3, 301-420
with supplementary observations, sections, and a map by R.I.Murchison.

An enormous paper, and difficult to reference; we approach it via the writings of Horner and Lyell.
Horner (1836, p.460): " In the synopsis of the successive deposits in the basin of Vienna, given by Mr.Murchison, the uppermost is described to be 'Alluvial loam, called Loess, with terrestrial shells of existing species.. mixed with bones of elephants of extinct species. The average thickness of this deposit is about 60ft but at some places the thickness is much greater. Further, it is greatly expanded near Krems and St.Polten, reaching occasionally the thickness of 140ft, and having, near these places, the exact appearance of the old alluvial hillocks in the valley of the Rhine, which have been described by M.Voltz.." 
We appear to have early references to the loess in the Danube basin; in fact these might be among the earliest references to loess in the Danube basin..

Charles Lyell is in Europe in July 1835, he writes to Sedgwick: " I am reading you and Murchison on the Eastern Alps, as I am going so near your section. Your elaborate joint paper is now quite a treat. Boue has given me many Gosau fossils. He is going to live four years in Vienna, and next year to do the Balkan. My wife says, 'Give my kind regards to Mr.Sedgwick, and tell him it is dreadfully hot.'
Lyell deploys a well chosen phrase-'your elaborate joint paper; its impressive that he carried so much paper with him.  This elaborate joint paper appears to have been a bit neglected subsequently; no mention in the detailed history of Danube loess research by Markovic et al (2016)- not surprising, the material is well hidden but the 140ft thick loess at Krems deserves a mention.

The history of Danube loess research 2016.  Markovic, S.B., Fitzsimmons, K.E., Sprafke, T., Gavrilovic, D., Smalley, I.J., Jovic, V., Svircev, Z., Gavrilov, M.B., Beslin, M.  Quaternary International 399, 76-89.

Zalasiewicz on Geology

Jan Zalasiewicz  2018.  Geology: A Very Short Introduction.  Oxford University Press 145p.

JZ presents the story of geology in the compact format of the 'Very Short Introduction' series by OUP.  There are over 550 titles in the VSI series and 'Geology' is a welcome addition.

Earth history from the very beginning to the Anthropocene- neatly illustrated; -and properly indexed. Go to L in the index, look for Loess- we have an entry- p.83. We will have to quote- the temptation is too great:
"These are still widely called 'drift' deposits (from the old idea that many formed from drifting icebergs), but are more technically referred to as 'superficial' or 'surficial' deposits. Not all relate to glaciation, by any means. In low latitude parts of the world they can include thick windblown sand deposits, as in parts of the Sahara, or the thick windblown silt or loess that covers much of Central China, having been blown there during the past two and a half million years from the Himalayas, and peat bog deposits. Where large rivers such as the Mississippi or Ganges-Brahmaputra meet the sea, huge deltas build out. "
Good to see the Himalayas acknowledged as the source of loess material; and two and a half million years of loess deposition. Is Central China the place or would the loess region be better described as northern China? and where do the peat bog deposits contribute? 

Another relevant VSI book is The Ice Age by Jamie Woodward:
Jamie Woodward 2014.  The Ice Age: A Very Short Introduction.  Oxford University Press 163p.

This is in many ways an excellent study of Quaternary matters- but there is one terrible short-coming.
Look in the index, go to L- where is Loess?  Why does JW not mention loess? surely Loess is one of the most interesting and significant of the Ice Age deposits.

Adobe as Loess (Why not?)

Alfred Scheidig (1934) in his classic book 'Der Loess und seine geotechnischen Eigenschaften' stated that:  In addition to the aforementioned loesses, which are mainly of glacial origin, there are continental loesses in the fringe regions around desert and steppe zones. Keilhack (1920) mentions this in Texas, Shaler (1899) in Montana, Henning (1911) in Colorado, New Mexico and Arizona. In the latter two areas, the loess is closely related to the formation known as 'adobe' (pronounced adobi) in fact, in most cases it is identical to adobe (translated by LL).

Adobe is widely used as a building material in Africa- in and around the 15N region; it is also used in the S.W.USA; these are probably the best known adobe regions. The sources of adobe material in Africa can perhaps be demarcated.

On the map <<<  FJ is the Fonta-Djalon highlands; BD is the Bodele depression; EH is the Ethiopian highlands. Also indicated- the catchment of the River Niger.  The highlands can be seen as particle-source regions- possibly for loess sized particles. The Bodele depression is the classic source region for small dust particles- derived from deposits in ancient Lake Chad. This can deliver clay-mineral material and silica diatoms. A lot of interesting particulate material is available in the 15N region. For the adobe reaction to function effectively there needs to be some carbonates in the system. The Ethiopian Highlands deliver large amounts of silt-sized material for the Nile Valley deposits and also makes material available for the eastern parts of the adobe region. There are actually few well defined loess deposits in Africa- but there must be a large amount of usable material in accessible regions.

 

Onn Crouvi and associates have provided a neat map of Africa showing loess deposits and the critical regions. The countries of Mauritania, Mali, Niger and Chad cover much of this region; classic adobe buildings are found in this zone.

Crouvi, O., Amit, R., Enzel, Y., Gillespie, A.Ar. 2010.  Active sand seas and the formation of desert loess.  Quaternary Science Reviews 29, 2087-2098.

 

Brickmakers at Mohenjo Daro

Bricks are ubiquitous at Mohenjo Daro and Harappa. Bricks were important in the Indus Valley settlements. The ancient Chinese society left us many objects and much writing; the ancient Egyptians left us an entire academic discipline; the Indus Valley people mostly left us bricks.

Very few artefacts- most famously the bronze statuette of the young woman dancer and the 'Priest/King' stone bust; but very many bricks- good quality fired bricks in enormous numbers. Can we study the Indus Valley people more closely via their bricks? Can we mobilize brick specialists to tell us more?- via a study of bricks.
We propose that these were loess bricks. Loess is known as excellent brickearth; the positioning of the loess deposits may have influenced the location of the brick built cities. Great brick buildings extend beyond Hampton Court Palace and St.Pancras station, they include the city structures at Mohenjo Daro and Harappa. The loess deposits in Kent & Essex supplied the bricks for Victorian London; the Indus Valley loess supplied the bricks for Mohenjo Daro.

The bricks at Harappa were discovered before the city (can we say that?). When the Lahore -Karachi railway was being constructed in 1856 the constructors discovered large deposits of hard, strong bricks which they used to construct the trackbed foundations for many miles of track (about 100 miles). These four thousand year old bricks provided excellent ballast material. The old Harappans made amazingly good bricks- possibly because they had the best available brickearth. Perhaps the brickmakers were important people in Indus Valley societies; perhaps the priest/king is really a brickmaker.

Figures from:
J.M.Kenoyer 1991. The Indus Valley traditions of Pakistan and western India. Journal of World Prehistory 5 (4)  331-385
 

Loess & Society: the Indus Valley civilizations ~3000 BCE - 1500 BCE.

The Chinese society grew, developed and flourished in the loess regions associated with the eastern parts of High Asia. This was/is the most impressive and longest lasting of the ancient civilizations and it can be argued that it owes much of its success to its firm foundation in the loess lands. There were/are loess lands associated with the western end of High Asia; not so spectacular and amazing as the Chinese occurrences but significant and deserving of appreciation. The Central Asian loess has been studied and investigated but the loess now in India and Pakistan has been neglected and its societal influence has not been fully appreciated. The Indus Valley was the home for well developed societies in the period of around 3000-1500 BCE; two centres are identified: Harappa and Mohenjo Daro and they both appear to have interesting loessic connections. Here were well developed societies with brick buildings, built with fired bricks, and an alphabet or writing system, which still needs to be significantly translated.

Some of these symbols appear to have geomorphological significance. There are four major rivers in the Punjab- the Jhelum, Chenab, Ravi & Sutlej dominate the region, and are closely associated with the Harappan society. The better known Mohenjo Daro situation is located further down the Indus Valley. The loess deposits in the Indus Valley are not well demarcated; there has not been much mapping activity, but the two deposits indicated by S.Z.Rozycki correspond nicely with the two sites of ancient societies

.
Region 7 on the High Asia diagram is where we find the Indus Valley civilizations; region 1 is the Central Asian loess region; the two rivers indicated are the Amu-Darya and the Syr-Darya. Regions 3 & 4 contain the Chinese loess deposits.

S.Z.Rozycki  1991.  Loess and Loess-like Deposits. Ossolinium Wroclaw. On p.117 in the section on Local Loesses of Southern Asia - one of the very few maps of loess in India region. SZR has made the picture rather too complex but he manages to show the two loess regions: NE of the Thar desert and W of the Thar desert; the locations of the Harappan and Mohenjo-Daro civilizations.

 Bricks. Thoughts about bricks. The Indus Valley people built with fired bricks; and they built extensively- there was a lot of brick construction in Harappa and Mohenjo Daro. So they must have had good access to large deposits of suitable brickearth- the sort of brickearth that encouraged the making of fired bricks. It has been suggested that the location of early brick buildings in England was to some extent controlled by access to loessic brickearth- for the construction of suitable bricks. Similar constraints could apply in the Indus Valley; city location may depend on the provision of material for making bricks. In the case of Mohenjo Daro the city appears to be placed exactly on the loess region demarcated by Rozycki. A large patch of suitable loess providing building material for a substantial city. And there must have been plenty of wood available; we see the bricks being fired in clamps with wood as the fuel. A lot of bricks requires a lot of wood.

The bricks were made to a 4:2:1 ratio; the sizes were 10 x 20 x 40cms or 7 x 14 x 28 cms. These are large bricks; the smaller bricks appear to been used in houses and the larger bricks in public buildings. They were well laid and many of the constructions have lasted remarkably well.

The question of the big brick.
Reports suggest that fired bricks were used to construct the buildings at Harappa and Mohenjo Daro. Also it is suggested that some of these were very large- the big bricks 10 x 20 x 40 cms; far too large to be conveniently handled. The normal European brick in the 21st Century has dimensions of about 6 x 10 x 21 cm. It is designed to fit the hand of the bricklayer, and also be of a weight which he or she can lift and manipulate.
To be able to produce, to move, and to construct with these large bricks suggests a very well organised and efficient society. The number of bricks used in Harappa and Mohenjo Daro is enormous- so vast brickearth resources were required, and large amounts of fuel for firing. But it is the size of the large brick which causes questions. It is too big; it requires two people to handle it- particularly in the unfired state; great skill and dexterity would have been required. And to get satisfactory firing.. difficult.

Are the reports perhaps mistaken? The reported smaller Indus Valley brick at 7 x 14 x 28 cm is not that much larger than the standard European brick and would seem to have been a logical size for normal use. We need a brick measuring expedition to the Indus Valley to measure the bricks, and try
to locate the regions where they were produced.