 |
| John Hardcastle; aged about 60, or early sixties(above) A Brad Pillans map of the South Island showing the location of Timaru. Note the basalt volcanics at Timaru- and nowhere else in the South Island |
Tuesday, 22 April 2014
John Hardcastle of Timaru
Saturday, 19 April 2014
Depressions in Loess Ground; on the Titel Plateau, and at Timaru in South Canterbury NZ
Christian Zeeden, Michael Hark, Ulrich Hambach, Slobodan B. Markovic, Ludwig Zoeller 2007
Depressions on the Titel Loess Plateau: Form-Pattern-Genesis. Geographica Pannonica 11, 4-8.
These depressions are fairly shallow, maybe up to 4m in depth; perhaps 50, 100, 200m wide- shallow bowl-like depressions on/in the loess ground surface. Investigated by Zeeden et al- who hint at formation aided by some dissolution processes. One wonders if there might be selective and localised hydrocollapse going on. The Titel depressions have a preferred northwest-southeast orientation which obviously could be significant. To investigate loess hollows more examples are required.. and the ancient literature may have revealed one. John Hardcastle, discussing the Timaru loess in his 'Notes on the Geology of South Canterbury'(1908) mentions some depressions which sound remarkably like the Titel depressions. He gives few details but hopefully some investigations can be launched. There does not appear to be any obvious reason why the Titel and Timaru loess deposits should not be very similar.
Depressions on the Titel Loess Plateau: Form-Pattern-Genesis. Geographica Pannonica 11, 4-8.
These depressions are fairly shallow, maybe up to 4m in depth; perhaps 50, 100, 200m wide- shallow bowl-like depressions on/in the loess ground surface. Investigated by Zeeden et al- who hint at formation aided by some dissolution processes. One wonders if there might be selective and localised hydrocollapse going on. The Titel depressions have a preferred northwest-southeast orientation which obviously could be significant. To investigate loess hollows more examples are required.. and the ancient literature may have revealed one. John Hardcastle, discussing the Timaru loess in his 'Notes on the Geology of South Canterbury'(1908) mentions some depressions which sound remarkably like the Titel depressions. He gives few details but hopefully some investigations can be launched. There does not appear to be any obvious reason why the Titel and Timaru loess deposits should not be very similar.
Monday, 10 March 2014
JH in NZ: Loessic intimations of John Hardcastle
JH in NZ: Loessic intimations of John Hardcastle
John Hardcastle (1847-1927) was born in Yorkshire, England. There is some dispute about whether he was born in Beverley, or in Wakefield; East Riding vs.West Riding. Wakefield is probably right. He went to New Zealand as a child and spent much of his life at Timaru, on the east coast of the South Island. He spent many years associated with the Timaru Herald newspaper. He was a scholar and a scientist and in the years 1889-1890 published two very significant papers on loess.(see Smalley et al.2001).
He had access to the Dashing Rocks section at Timaru, described by J.D.Raeside as the chief candidate to be the type section of the NZ loess. JH was a meticulous field scientist and he recorded his observations on the loess in his papers in the Transactions and Proceedings of the New Zealand Institute. He was a member of the Philosophical Institute of Canterbury, part of the NZ Institute, which met in Christchurch, not too far from Timaru.
His 1890 paper was the first to point out that loess could act as a 'climate register' - the loess contained a record of the changing climate. This must have been one of the first real observations in the science of palaeoclimatology. These climatic observations are being recognized but it is becoming apparent that some other of his observations and considerations deserve to be more fully examined. In the 1889 paper he examined the processes of loess deposit formation and he was the first to propose the breaking down of the process into defineable stages or events. This was not proposed again until 1966, and is still being refined. The event sequence P1T1D1T2D2 should be named the Hardcastle sequence- this is the default sequence for the formation of a basic loess deposit.
P1 formation of material by cold processes in mountains
T1 transportation of material by rivers
D1 deposition on flood plains
T2 aeolian transportation of loess material
D2 formation of open structured metastable loess deposit
This sequence works well for the Timaru loess, with the Southern Alps providing the P1 provenance action. JH was perceptive at the P1 level and was probably the first to emphasize the role of glacial action in loess formation. He reported climatic effects recorded in the loess and in the course of doing so made the first description of a fragipan horizon. The fragipan is a hard, diagnostic soil horizon, associated with loess deposits and essentially named and defined by Guy Smith around 1948. Smith defined it but JH had already provided a beautiful description; the fragipans at Dashing Rocks are impressive and accessible. This first fragipan description should be recognized. JH was also very perceptive on the observation of bird crop stones distributed in the loess; he felt that these had stratigraphic and climatic value- and this is a topic which has not been fully explored even now. Perhaps more pertinent in NZ because moa crop stones are observed and these could offer useful information in various fields.
The Timaru loess should be recognized as a very significant deposit; steps should be taken to preserve and appreciate it. This could be a major geoheritage/geotourism site. The site should be recognized and so should John Hardcastle. He had an annus mirabilis in 1889-1890 and wrote two brilliant papers which unfortunately were not appreciated at the time Albert Einstein had an annus mirabilis in 1905 and the papers he wrote changed the world. That short burst of brilliance perhaps characterises the outstanding scholar and JH should certainly be seen as outstanding, and given much credit in the development of loess science.
Fagg, R. 2001. John Hardcastle (1847-1927) A gifted amateur. Geological Society of New Zealand Historical Studies Group Newsletter 22, 21-25.
Smalley, I.J. 1983. John Hardcastle on glacier motion and glacial loess. Journal of Glaciology 29, 480-484.
Smalley, I.J., Jefferson, I.F., Dijkstra, T.A., Derbyshire, E. 2001. Some major events in the development of the scientific study of loess. Earth Science Reviews 54, 5-18.
John Hardcastle (1847-1927) was born in Yorkshire, England. There is some dispute about whether he was born in Beverley, or in Wakefield; East Riding vs.West Riding. Wakefield is probably right. He went to New Zealand as a child and spent much of his life at Timaru, on the east coast of the South Island. He spent many years associated with the Timaru Herald newspaper. He was a scholar and a scientist and in the years 1889-1890 published two very significant papers on loess.(see Smalley et al.2001).
He had access to the Dashing Rocks section at Timaru, described by J.D.Raeside as the chief candidate to be the type section of the NZ loess. JH was a meticulous field scientist and he recorded his observations on the loess in his papers in the Transactions and Proceedings of the New Zealand Institute. He was a member of the Philosophical Institute of Canterbury, part of the NZ Institute, which met in Christchurch, not too far from Timaru.
His 1890 paper was the first to point out that loess could act as a 'climate register' - the loess contained a record of the changing climate. This must have been one of the first real observations in the science of palaeoclimatology. These climatic observations are being recognized but it is becoming apparent that some other of his observations and considerations deserve to be more fully examined. In the 1889 paper he examined the processes of loess deposit formation and he was the first to propose the breaking down of the process into defineable stages or events. This was not proposed again until 1966, and is still being refined. The event sequence P1T1D1T2D2 should be named the Hardcastle sequence- this is the default sequence for the formation of a basic loess deposit.
P1 formation of material by cold processes in mountains
T1 transportation of material by rivers
D1 deposition on flood plains
T2 aeolian transportation of loess material
D2 formation of open structured metastable loess deposit
This sequence works well for the Timaru loess, with the Southern Alps providing the P1 provenance action. JH was perceptive at the P1 level and was probably the first to emphasize the role of glacial action in loess formation. He reported climatic effects recorded in the loess and in the course of doing so made the first description of a fragipan horizon. The fragipan is a hard, diagnostic soil horizon, associated with loess deposits and essentially named and defined by Guy Smith around 1948. Smith defined it but JH had already provided a beautiful description; the fragipans at Dashing Rocks are impressive and accessible. This first fragipan description should be recognized. JH was also very perceptive on the observation of bird crop stones distributed in the loess; he felt that these had stratigraphic and climatic value- and this is a topic which has not been fully explored even now. Perhaps more pertinent in NZ because moa crop stones are observed and these could offer useful information in various fields.
The Timaru loess should be recognized as a very significant deposit; steps should be taken to preserve and appreciate it. This could be a major geoheritage/geotourism site. The site should be recognized and so should John Hardcastle. He had an annus mirabilis in 1889-1890 and wrote two brilliant papers which unfortunately were not appreciated at the time Albert Einstein had an annus mirabilis in 1905 and the papers he wrote changed the world. That short burst of brilliance perhaps characterises the outstanding scholar and JH should certainly be seen as outstanding, and given much credit in the development of loess science.
Fagg, R. 2001. John Hardcastle (1847-1927) A gifted amateur. Geological Society of New Zealand Historical Studies Group Newsletter 22, 21-25.
Smalley, I.J. 1983. John Hardcastle on glacier motion and glacial loess. Journal of Glaciology 29, 480-484.
Smalley, I.J., Jefferson, I.F., Dijkstra, T.A., Derbyshire, E. 2001. Some major events in the development of the scientific study of loess. Earth Science Reviews 54, 5-18.
Tuesday, 31 December 2013
23 Topics for Loess Research
23 Topics for Loess Research [in 21st Century]
In 1900, at the International Conference of Mathematicians in Berlin, the famous mathematician David Hilbert offered a list of problems and topics to be considered in the 20th Century. This list became very famous and to some extent influenced the direction of mathematical research and scholarship; it set out directions and targets. Now, in a scaled-down, much more modest version of the target setting exercise we offer some target topics for loess research in the 21st Century. Hilbert offered 23 topics/problems and therefore we shall do the same: the 23 Topics for Loess Research:
1. Words. Words have always been a problem; the word Loess requires lengthy explanations when introduced into conversations. Remarkably few people know what loess is- we need an educational programme. There may be a way forward in the use of loess as an adjective; loess ground has some virtues- we speak of loess deposits, loess soils, loess material.. Ground studies are beset by imprecision, we talk of clay when it is unclear whether we mean clay size or clay mineral. Requirement: more precision with words; a more perceptive use of words.
2. Particles. Loess is one of the classic particulate sediments. There are particulate generalizations that can be made; Loess is described as a silty sediment, and the mode mineralogy appears to be quartz. The mode particle might be considered as a 30um diameter quartz particle. The on-going problems relate to the factors constraining the particle size range, and the mode of formation of the particles.
3. Structures. A defining factor for a loess deposit is the open structure, caused by the airfall mode of formation of the deposit. Loess deposit as particle packing; the packing structure of a loess deposit cannot be defined, although it can be modelled in various ways, which can give interesting and useful results. How to describe a packing; the one truly unanswerable question on the list.
4. Bonds. Bonding between particles. The open structure is maintained by a set of interparticle bonds. In the loess system there is a complex interaction between short range and long range bonds. The basic system of primary mineral particles will be bonded by short range contact bonds but the interesting behaviour is mediated by long range, clay-mineral type bonds.
5. Collapse. Initial collapse depends on clay mineral material which is concentrated at the major contact points in the metastable structure. The hydroconsolidation process becomes clearer and better understood, but further investigations are definitely needed.
6. Mineralogy. Quartz is seen to dominate, but other minerals will become more important as they are used as indicators of provenance and age. Sophisticated mineralogy will continue to impress.
7. Dust/Loess relationships. If loess is large dust with a mode size around 30um and small dust(travelling high in suspension dust) has a mode size of say around 3um.. are there other modes in this general size range or are there really basically two types of dust? Confusion has arisen because of a failure to identify the nature of dust material in many studies.
8. Places. Where is the loess? do we know? How well is the world's loess mapped? Is there widespread loess in Pakistan and N.W.India? How about Africa? the Kriger 1965 map showed no loess in Africa but there could be modest deposits. Loess is Siberia deserves to be better known. For various reasons various loess places have not been recognized and explored and investigated; some geographical action is required.
9. pL Loessification. Loessification has been sub-divided into small scale loessification (pL) and large scale loessification (gL). There is some interest in pL processes because they are seen as operating after Aeolian deposition. They serve to make the ground more loessic. The gL processes have been dismissed as too extreme, but pL processes, in particular the development of collapsibility, appear to merit further study.
10. PTDC systems. P provenence, the formation of loess material; T transportation, the moving of loess material; D deposition, the deposition of loess material, the formation of loess deposits; C change in the deposit. The C process has recently been added to the PTDC system- it may be here that attention is focussed, although the recognition of river action in the T stage is developing. In the C stage we find chernozemisation; C might stand for chernozemisation- it actually stands for change. The P and T processes fit securely in the world of sedimentology, the C processes are probably in the world of pedology. The D processes are transition processes. This transition has caused problems in earlier loess discussions.
11. Dating. Central to the study of loess. New techniques will be developed; greater reliability and precision will be achieved. The last 2 million+ years will be dated via the loess.
12. Climates The alternation of loess and palaeosol gives a clear indication of climate change; precision can be improved. The Hardcastle observation(the loess/climate link) turns out to be one of the most fundamental and important in loess research.
13. Rivers. We see the Danube as a loess river, but what about the Niger, Indus, Dnepr, Ob. Rivers may have a key role to play in the T stage of the loess deposit formation process.
14. Other Planets. Mars maybe? Titan maybe? We need to be aware that the idea of loess on other planets may present interesting scientific challenges. The PTDC criteria will need to be applied; will they work on other planets?
15. Erosion. Wind and water. Tensile failure; a disruption of the soil structure, a dispersion of the components, the breaking of the bonds which keep the structure intact. Loess ground may be the most erodible ground; counter erosion activities may need to be focussed on loess.
16. Deformation. This could be mostly problems with slope stability, which still pose a large problem, particularly in China. Or it could deal with what has been called the 'Teton Dam' problem- the difficult properties displayed by remoulded loess. The great geotechnical problem related to loess arises from the collapse of the open structure and this has garnered most of the attention, but there are problems with remoulded loess.
17. Cyclicity. Milankovitch gave cyclicity to the Quaternary. The cyclicity of the Quaternary is also manifested in the alternation of loess and palaeosol. There are views through other windows showing cyclicity; all shall be reconciled.
18. Larger Animals. Mammoths for example. Mammoth remains are found in loess deposits. It may be that mammoths had a special relationship to loess terrain; the Mammoth Steppe could have been a particularly loessic zone. More studies of the Mammoth/loess relationship are required. And studies of other large animals in the loess.
19. Smaller Animals. Cyanobacteria down at the very small level; here is a promising region of study and research. Snails- the classic small animals in loess; Lyell was impressed by the snails in the loess and modern malacologists maintain a high level of interest.
20. Agriculture. Ward Chesworth said that loess soils are the best soils. Loess brings good soil structure and good nutrient status; given enough water this is the ideal soil. The addition of loess material to a soil which is not obviously a loess soil gives added virtue. The soils of southern England are better soils for a sprinkling of loess. These loess-augmented soils need to be further investigated.
21. Civilization. The Chinese civilization, founded in the loess, is the oldest civilization. Loess promotes civilization. The early Europeans advanced up the Danube valley from loess deposit to loess deposit, and invented European art on the way (mostly at Willendorf).
22. Language. Varieties of English seem to have taken over the role of communication within the world of science. We need to be a little cautious in the world of loess, for good historical reasons. Loess study begins in 1824 and most of the early work was in German. Loess study is in many ways a regional study and we need to be aware of regional material written in regional languages. This is particularly true of Russian; there is a vast literature in Russian which will continue to have relevance for many years.
23. eWorld. Suddenly the whole world is the computer world. All science occurs within computer world, and loess scientists and scholars, like all scientists and scholars have to adapt. Is there are sort of loess/computer connection that needs to be recognised/exploited? Has the incorporation of loess science into eWorld forced any changes or adjustments? This might be a really fundamental question, or it might be that the changes only occur at a second order level and affect the way we store our data and publish our results.
23 entries- and this is just a trial list. Please make suggestions for additions and alterations. Like the various loess historical lists which have appeared lately this list has a large subjective content. It is open to modification.
.
In 1900, at the International Conference of Mathematicians in Berlin, the famous mathematician David Hilbert offered a list of problems and topics to be considered in the 20th Century. This list became very famous and to some extent influenced the direction of mathematical research and scholarship; it set out directions and targets. Now, in a scaled-down, much more modest version of the target setting exercise we offer some target topics for loess research in the 21st Century. Hilbert offered 23 topics/problems and therefore we shall do the same: the 23 Topics for Loess Research:
1. Words. Words have always been a problem; the word Loess requires lengthy explanations when introduced into conversations. Remarkably few people know what loess is- we need an educational programme. There may be a way forward in the use of loess as an adjective; loess ground has some virtues- we speak of loess deposits, loess soils, loess material.. Ground studies are beset by imprecision, we talk of clay when it is unclear whether we mean clay size or clay mineral. Requirement: more precision with words; a more perceptive use of words.
2. Particles. Loess is one of the classic particulate sediments. There are particulate generalizations that can be made; Loess is described as a silty sediment, and the mode mineralogy appears to be quartz. The mode particle might be considered as a 30um diameter quartz particle. The on-going problems relate to the factors constraining the particle size range, and the mode of formation of the particles.
3. Structures. A defining factor for a loess deposit is the open structure, caused by the airfall mode of formation of the deposit. Loess deposit as particle packing; the packing structure of a loess deposit cannot be defined, although it can be modelled in various ways, which can give interesting and useful results. How to describe a packing; the one truly unanswerable question on the list.
4. Bonds. Bonding between particles. The open structure is maintained by a set of interparticle bonds. In the loess system there is a complex interaction between short range and long range bonds. The basic system of primary mineral particles will be bonded by short range contact bonds but the interesting behaviour is mediated by long range, clay-mineral type bonds.
5. Collapse. Initial collapse depends on clay mineral material which is concentrated at the major contact points in the metastable structure. The hydroconsolidation process becomes clearer and better understood, but further investigations are definitely needed.
6. Mineralogy. Quartz is seen to dominate, but other minerals will become more important as they are used as indicators of provenance and age. Sophisticated mineralogy will continue to impress.
7. Dust/Loess relationships. If loess is large dust with a mode size around 30um and small dust(travelling high in suspension dust) has a mode size of say around 3um.. are there other modes in this general size range or are there really basically two types of dust? Confusion has arisen because of a failure to identify the nature of dust material in many studies.
8. Places. Where is the loess? do we know? How well is the world's loess mapped? Is there widespread loess in Pakistan and N.W.India? How about Africa? the Kriger 1965 map showed no loess in Africa but there could be modest deposits. Loess is Siberia deserves to be better known. For various reasons various loess places have not been recognized and explored and investigated; some geographical action is required.
9. pL Loessification. Loessification has been sub-divided into small scale loessification (pL) and large scale loessification (gL). There is some interest in pL processes because they are seen as operating after Aeolian deposition. They serve to make the ground more loessic. The gL processes have been dismissed as too extreme, but pL processes, in particular the development of collapsibility, appear to merit further study.
10. PTDC systems. P provenence, the formation of loess material; T transportation, the moving of loess material; D deposition, the deposition of loess material, the formation of loess deposits; C change in the deposit. The C process has recently been added to the PTDC system- it may be here that attention is focussed, although the recognition of river action in the T stage is developing. In the C stage we find chernozemisation; C might stand for chernozemisation- it actually stands for change. The P and T processes fit securely in the world of sedimentology, the C processes are probably in the world of pedology. The D processes are transition processes. This transition has caused problems in earlier loess discussions.
11. Dating. Central to the study of loess. New techniques will be developed; greater reliability and precision will be achieved. The last 2 million+ years will be dated via the loess.
12. Climates The alternation of loess and palaeosol gives a clear indication of climate change; precision can be improved. The Hardcastle observation(the loess/climate link) turns out to be one of the most fundamental and important in loess research.
13. Rivers. We see the Danube as a loess river, but what about the Niger, Indus, Dnepr, Ob. Rivers may have a key role to play in the T stage of the loess deposit formation process.
14. Other Planets. Mars maybe? Titan maybe? We need to be aware that the idea of loess on other planets may present interesting scientific challenges. The PTDC criteria will need to be applied; will they work on other planets?
15. Erosion. Wind and water. Tensile failure; a disruption of the soil structure, a dispersion of the components, the breaking of the bonds which keep the structure intact. Loess ground may be the most erodible ground; counter erosion activities may need to be focussed on loess.
16. Deformation. This could be mostly problems with slope stability, which still pose a large problem, particularly in China. Or it could deal with what has been called the 'Teton Dam' problem- the difficult properties displayed by remoulded loess. The great geotechnical problem related to loess arises from the collapse of the open structure and this has garnered most of the attention, but there are problems with remoulded loess.
17. Cyclicity. Milankovitch gave cyclicity to the Quaternary. The cyclicity of the Quaternary is also manifested in the alternation of loess and palaeosol. There are views through other windows showing cyclicity; all shall be reconciled.
18. Larger Animals. Mammoths for example. Mammoth remains are found in loess deposits. It may be that mammoths had a special relationship to loess terrain; the Mammoth Steppe could have been a particularly loessic zone. More studies of the Mammoth/loess relationship are required. And studies of other large animals in the loess.
19. Smaller Animals. Cyanobacteria down at the very small level; here is a promising region of study and research. Snails- the classic small animals in loess; Lyell was impressed by the snails in the loess and modern malacologists maintain a high level of interest.
20. Agriculture. Ward Chesworth said that loess soils are the best soils. Loess brings good soil structure and good nutrient status; given enough water this is the ideal soil. The addition of loess material to a soil which is not obviously a loess soil gives added virtue. The soils of southern England are better soils for a sprinkling of loess. These loess-augmented soils need to be further investigated.
21. Civilization. The Chinese civilization, founded in the loess, is the oldest civilization. Loess promotes civilization. The early Europeans advanced up the Danube valley from loess deposit to loess deposit, and invented European art on the way (mostly at Willendorf).
22. Language. Varieties of English seem to have taken over the role of communication within the world of science. We need to be a little cautious in the world of loess, for good historical reasons. Loess study begins in 1824 and most of the early work was in German. Loess study is in many ways a regional study and we need to be aware of regional material written in regional languages. This is particularly true of Russian; there is a vast literature in Russian which will continue to have relevance for many years.
23. eWorld. Suddenly the whole world is the computer world. All science occurs within computer world, and loess scientists and scholars, like all scientists and scholars have to adapt. Is there are sort of loess/computer connection that needs to be recognised/exploited? Has the incorporation of loess science into eWorld forced any changes or adjustments? This might be a really fundamental question, or it might be that the changes only occur at a second order level and affect the way we store our data and publish our results.
23 entries- and this is just a trial list. Please make suggestions for additions and alterations. Like the various loess historical lists which have appeared lately this list has a large subjective content. It is open to modification.
.
Thursday, 5 December 2013
Charles Darwin comments on Loess
There is only one mention of loess in the 'Origin of Species':
"We have evidence in the loess of the Rhine of considerable changes of level in the land within a very recent geological period, and when the surface was peopled by existing land and fresh-water shells". (1859; Folio ed.p.305).
It is a very modest mention, but it merits some discussion. Some important geological concepts are embedded in this short quotation. We see Darwin indebted to Lyell for geological ideas. There are two Lyell concepts to the fore here- the importance of vertical movements of the land in geological processes, and the idea that loess is a lacustrine deposit. The lacustrine idea is used as an indicator, a verifier, for the vertical movement idea.
"We have evidence in the loess of the Rhine of considerable changes of level in the land within a very recent geological period, and when the surface was peopled by existing land and fresh-water shells". (1859; Folio ed.p.305).
It is a very modest mention, but it merits some discussion. Some important geological concepts are embedded in this short quotation. We see Darwin indebted to Lyell for geological ideas. There are two Lyell concepts to the fore here- the importance of vertical movements of the land in geological processes, and the idea that loess is a lacustrine deposit. The lacustrine idea is used as an indicator, a verifier, for the vertical movement idea.
Monday, 2 December 2013
FORE: First Order Rate Equations (& Loess)
Richard L. Handy 2013 FORE and the future of practically everything; a guess with a college education. Moonshine Cove Publishing, 150 Willow Pt., Abbeville SC 29620 214p.
A new book by Richard Handy (who previously brought you 'The Day the House Fell' and 'Soil Engineering'). Now we have a look at First Order Rate Equations (acronym FORE).
log y = ax + b
"This book uses a special kind of telescope that looks back in order to look ahead. That is, it uses information from the past to try and get a handle on the future. This is not ordinary speculation and is not fully ordained and consecrated speculation; it is scientific speculation. It is speculation that is based on a simple rule called a 'first-order rate equation'. Hence the acronym, FORE. The acronym also has a nice forward look about it".
The basic assumption. The basic assumption is that a rate of change depends on the amount of departure from some final equilibrium state. This means that a process has to stop when some key ingredient is all used up. That is not complicated.
A rate of change can be expressed by dy/dt, where dy represents a tiny bit of change and dt is a tiny snatch of time. The / means to divide, as in miles/hour. The assumption therefore is:
dy/dt = ky
That is a definition...
On p.177 is a picture of loess- a classic cold-climate deposit. The FORE equation appears to work well on cooling climatic cycles(but maybe not so well on warming cycles). It also has some application in a geotechnical context related to loess because it can be applied to subsidence. Now subsidence is the no.1 geotechnical problem related to loess and many measurements have been made and equations activated. Handy focusses thoughts on subsidence on to Kansai airport, not a loess application- but relatable to the loessic situation. Handy operates with confidence in the geotechnical regions, and with respect to loess has a remarkable pedigree. Material by Handy appeared in Loess Letter 3 (check it out at www.loessletter.msu.edu). In fact Handy might be held responsible for the existence of Loess Letter. LL was inspired by a newsletter called 'Screenings from the Soil Research Lab' which was published from Iowa State University in Ames from 1957 to 1964. Copies must have been distributed world-wide because a set was kept at the New Zealand Soil Bureau, in the Soil Engineering Section at Upper Hutt. Roy Northey, who ran the Soil Eng.Section, luckily kept everything and copies of Screenings were there to inspire the initiation of Loess Letter(and the New Zealand Government Printer was on hand to produce the early copies). There is a paper on the application of FORE in a geotechnical setting which is highly recommended:
Handy, R.L. 2002. First-order rate equations in geotechnical engineering. Amer. Soc. Civil. Engrs. Journal of Geotechnical Engineering 128, 416-425
Handy, R.L.(writing as anon.) 1980. The loess problem, the great American tragedy, or the war between the states. Loess Letter 3, 3-10. (http.www.loessletter.msu.edu).
A new book by Richard Handy (who previously brought you 'The Day the House Fell' and 'Soil Engineering'). Now we have a look at First Order Rate Equations (acronym FORE).
log y = ax + b
"This book uses a special kind of telescope that looks back in order to look ahead. That is, it uses information from the past to try and get a handle on the future. This is not ordinary speculation and is not fully ordained and consecrated speculation; it is scientific speculation. It is speculation that is based on a simple rule called a 'first-order rate equation'. Hence the acronym, FORE. The acronym also has a nice forward look about it".
The basic assumption. The basic assumption is that a rate of change depends on the amount of departure from some final equilibrium state. This means that a process has to stop when some key ingredient is all used up. That is not complicated.
A rate of change can be expressed by dy/dt, where dy represents a tiny bit of change and dt is a tiny snatch of time. The / means to divide, as in miles/hour. The assumption therefore is:
dy/dt = ky
That is a definition...
On p.177 is a picture of loess- a classic cold-climate deposit. The FORE equation appears to work well on cooling climatic cycles(but maybe not so well on warming cycles). It also has some application in a geotechnical context related to loess because it can be applied to subsidence. Now subsidence is the no.1 geotechnical problem related to loess and many measurements have been made and equations activated. Handy focusses thoughts on subsidence on to Kansai airport, not a loess application- but relatable to the loessic situation. Handy operates with confidence in the geotechnical regions, and with respect to loess has a remarkable pedigree. Material by Handy appeared in Loess Letter 3 (check it out at www.loessletter.msu.edu). In fact Handy might be held responsible for the existence of Loess Letter. LL was inspired by a newsletter called 'Screenings from the Soil Research Lab' which was published from Iowa State University in Ames from 1957 to 1964. Copies must have been distributed world-wide because a set was kept at the New Zealand Soil Bureau, in the Soil Engineering Section at Upper Hutt. Roy Northey, who ran the Soil Eng.Section, luckily kept everything and copies of Screenings were there to inspire the initiation of Loess Letter(and the New Zealand Government Printer was on hand to produce the early copies). There is a paper on the application of FORE in a geotechnical setting which is highly recommended:
Handy, R.L. 2002. First-order rate equations in geotechnical engineering. Amer. Soc. Civil. Engrs. Journal of Geotechnical Engineering 128, 416-425
Handy, R.L.(writing as anon.) 1980. The loess problem, the great American tragedy, or the war between the states. Loess Letter 3, 3-10. (http.www.loessletter.msu.edu).
Saturday, 30 November 2013
Loess near Tashkent
This is fig.10 (part of fig.10) from Scheidig 1934. This fantastic book is still a source of good things, and modified sketch maps will continue to be published. If one is allowed a little criticism it is that some of the maps are too small- so attempts at enlargement will be made.Here we are to the west of High Asia but the classic deterministic model of loess deposit formation works well. Particle origins in the high mountains, substantial rivers for material transportation etc. The cities of Samarkand and Tashkent are emphasized on the sketch map- this is a classic loess region; many loess investigators were based in Tashkent in Soviet times and there is continuing academic interest in the region.
Most of the literature is in Russian; there is a fairly recent review:
Smalley, I.J., Mavlyanova, N.G., Rahkmatullaev, Kh.L., Shermatov, M.Sh., Machalett, B., O'Hara-Dhand, K., Jefferson, I.F. 2006.. The formation of loess deposits in the Tashkent region and parts of Central Asia; and problems with irrigation, hydrocollapse and soil erosion. Quaternary International 152/153, 59-69.
[this paper should be accessible via the University of Birmingham website].
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