URL; http://start.org/news/call-for-proposals-disaster-risk-reduction-in-south-asia.html
START, with funding from CDKN, is pleased to announce a Call for Proposals (CFP) for research on integrating disaster risk reduction and climate change adaptation for resilient development in South Asia. We expect to fund up to five research projects of a maximum $100,000 USD for up to 19-months’ duration. The geographical scope of the CFP is Bangladesh, Bhutan, India, Maldives, Nepal, Pakistan, and Sri Lanka.
DEADLINE: 29 February 2012at Midnight (2400 hours) US Eastern Standard Time at the International START Secretariat office. Please submit electronically to: proposals@start.org.
About Me
Tuesday, January 17, 2012
Monday, January 16, 2012
European Geosciences Union
URL; http://www.egu.eu
Dedicated to the pursuit of excellence in the geosciences and the planetary
and space sciences for the benefit of humanity.
European Geosciences Union
General Assembly 2012
Vienna | Austria | 22 – 27 April 2012
Aims & Scope
The EGU General Assembly 2012 will bring together geoscientists from all over the world into one meeting covering all disciplines of the Earth, Planetary and Space Sciences. Especially for young scientists, it is the aim of the EGU to provide a forum where they can present their work and discuss their ideas with experts in all fields of geosciences. The EGU is looking forward to cordially welcoming you in Vienna.
Dedicated to the pursuit of excellence in the geosciences and the planetary
and space sciences for the benefit of humanity.
European Geosciences Union
General Assembly 2012
Vienna | Austria | 22 – 27 April 2012
Aims & Scope
The EGU General Assembly 2012 will bring together geoscientists from all over the world into one meeting covering all disciplines of the Earth, Planetary and Space Sciences. Especially for young scientists, it is the aim of the EGU to provide a forum where they can present their work and discuss their ideas with experts in all fields of geosciences. The EGU is looking forward to cordially welcoming you in Vienna.
Sunday, January 15, 2012
Critical comments on Trends in Himalayan Geology, Gerhard Fuchs
1. STRATIGRAPHY AND TECTONICS IN THE LESSER HIMALAYA
For decades there was dispute whether the unfossiliferous rock complex was Palaeozoic or Precambrian. On the basis of rare fossil finds and age data it is now generally accepted to be Precambrian to Early Cambrian (UPRETI, 1996; BHARGAVA et al., 2011).
In my view not yet settled is the correlation of the thick carbonate complexes of the Lesser Himalaya. SAKAI (1983), UPRETI (1996) and others regard the Kerabari and Krol Carbonates of the frontal zone (Parauthochtonous Unit, FUCHS, 1975) as Neoproterozoic. The Surtibang-, Dhading-, Shali-, and Deoban Carbonates of the inner zones are considered to be Midproterozoic (BHARGAVA et al., 2011). From the great lithological similarity and associated series a correlation of the two above named complexes should not be excluded.
Certainly a difficulty in the Stratigraphy is the confusion in nomenclature. Most authors introduce new names and their own scheme. My aim was to use the already existing and well-known terms like Chail, Shali, Krol etc from the type localities in India also in Nepal (FUCHS, 1967, 1977 and 1982; FUCHS & FRANK, 1970). These units can be traced along the Himalaya and are not confined by political borders. But my suggestion was not accepted.
Attempts have been made to subdivide the Kuncha-Chail complex by means of some conspicuous quartzite horizons (e.g. Fagfog Quartzite, STÖCKLIN, 1980). The quartzites, however, are of rather limited lateral extent. Thick conglomerate-quartzite bodies pass into pure phyllite series over a short distance along the strike. Probably they represent delta deposits and are not suitable for stratigraphical subdivision.
Closely connected with stratigraphy are tectonic problems. HAGEN (1969) proposed a complicated system of nappes. But he did not characterize their rock content and how they were discerned. The knowledge of the primary succession is necessary.
In the Hiunchuli region of West Nepal we found one of the rare occurrences where the stratigraphic order is still preserved (FUCHS & FRANK, 1970). Careful studies of the formation boundaries showed that they were stratigraphic, and the sedimentary structures indicated upright order. From bottom to top we find:
Green and white quartzites and phyllites (Chail, Kuncha).
Red and white quartzites and metapelites (Khaira, Nourpul).
Red and green slates and carbonates.
Black phyllites (Shali Slates, Benighat).
Blue and grey stromatolitic dolomites (Shali, Surtibang, Dhading).
This succession forms Chail Unit 1 (C1). After a thrust this sequence is repeated, but in reduced thickness W of Jangla Bhanjyang (C2), and above another thrust again phyllites and quartzites (Chail-Kuncha) follow representing C3. They are the topmost beds of the Lesser Himalaya immediately below the Main Central Thrust (MCT).
Towards the E the described successions pinch out and in the Kali Gandaki-Pokhara region we find only monotonous Kuncha-Chail Formation of vast extent. Carbonate marker horizons appear again in the Nawakot Complex W of the Kathmandu-Synclinorium (STÖCKLIN, 1980, map). These carbonates indicate thrusts at their top and make it probable that such tectonic planes exist also where the Chail-Kuncha rocks seem to form a uniform complex.
There are also authors who deny nappes in the Lesser Himalaya (ARITA et al., 1984). They accept the crystalline outliers as allochthonous, but the underlying Midland complex they take as autochthonous, affected only by vertical movements. That implies that the succession observed in the latter is stratigraphic. This assumption is disproved by our work (FUCHS, 1977) in the Galwa Window (HAGEN, 1969). In the core of this large dome we find stromatolitic dolomite with varicoloured carbonates and metapelites (C1). This unit is overthrust by Kuncha-Chail Formation succeeded by varicoloured conglomerates and quarzites, which in turn are overlain by thick dolomite (C2). Above another thrust Kuncha-Chail Formation follows (C3) forming the top of the Lesser Himalayan sequence under the MCT (FUCHS, 1977, Plate 1). The lowest of these units (C1) may be autochthonous, the upper units definitely are nappes (C2, C3); dragged by the overthrusting Crystalline Nappes the C3 shows the largest width of transport with outliers on the Mahabharat Range (S of Daban, Phalabang; FUCHS & FRANK, 1970, Plate 1). C3 has also wide extent in Ranimatta-Dailekh area N of Surkhet (FUCHS, 1977, Plate 1). The quartzites, phyllites and metabasics of the Kuncha-Chail Formation are also accompanied by granites. The latter intruded the Chails and are frequent in the Western Himalaya. Their ages cluster around 1800 Ma (FRANK et al., 1995).
Another problem is the Krol belt – is it a nappe or a frontal folded wedge of the Lesser Himalaya? I have introduced the term Parautochthonous Unit for it. It overthrusts the Tertiary Zone along the Main Boundary Thrust (MBT), but always has formed the southernmost part of the Lesser Himalaya. The frequent occurrence of Gondwana and Tertiary beds shows its proximity to the Indian Craton (Garhwal-, Tansing Synclines). There are no outliers or relics of a “Krol Nappe” N of the frontal range, at the base of the Crystalline klippes or the MCT. The superposition of the Chail Nappes is evident from the outliers of Satengal, Banali, Lansdowne and the Mahabharat Range (FUCHS & FRANK, 1970; FUCHS & SINHA, 1978). The Parautochthonous Unit is not metamorphosed or of only low grade. The assumption of a Krol Nappe implies that this unit would be intercalated between the greenschist metamorphosed Midland complex (Chail Nappes) and the amphibolite facies grade Crystalline Nappes. This was nowhere observed, rather an increase in metamorphic grade from lower to upper structural units (inverse metamorphism). Thus I regard the Krol belt as a folded wedge zone in the frontal part of the Lesser Himalaya.
2. CORRELATION CENTRAL CRYSTALLINE - CRYSTALLINE OUTLIERS
UPRETI (1995) hesitates to accept the Central Crystalline as a root zone of the crystalline klippes in the Lesser Himalaya, because of a series of differences.
Contrary I should like to stress that in eastern Nepal and Sikkim the root zone is still connected with the frontal parts of the Crystalline Nappe. In the western Himalaya the Crystalline Nappes with their sedimentary cover – the Kashmir and Chamba Synclinoria – can be traced to their roots in the High Himalaya Crystalline (HHC). It can be observed there that the highly migmatized gneiss complex becomes reduced towards the south and is replaced by less metamorphosed Salkalas. If we consider that the frontal portions of the Crystalline Nappe have been exposed to cooling when rocks of the root zone were still in the center of the regional metamorphism, differences are easily explained. Further it is a common experience that the basal portions of a nappe are frequently kept back by friction and the upper beds are enriched in the frontal parts (e.g. Kashmir Nappe). This may account for the smaller thickness of the gneiss-migmatite complex in the klippes.
Differences in the facies of the basal Tethyan sedimentary cover of the klippes (e.g. Kathmandu, Jaljala Dhuri) to the Tethyan Zone are explained by the fact that there are also facies changes within the Tethyan Zone. From the Nilgiri in the E to Kanjiroba in the W the silt content increases considerably. Similar changes in N-S direction can not be excluded.
Thus I see no necessity to introduce the term Mahabharat Thrust (UPRETI, 1995) at the base of the Kathmandu Klippe. We may safely take it as the MCT.
3. EARLY PALAEOZOIC OROGENY
At the beginning of my research in Nepal (FUCHS, 1967) I recognized the gradation from the Central Crystalline into the Cambro-Ordovician sediments of the Tibetan Zone by passing away of the metamorphism. Further I found a significant break in the sedimentary development at the Ordovician-Silurian boundary: Continental slope sedimentation (as we would say today) changed to a variety of platform facies. In context with the Ordovician unconformity in the W Himalaya (HAYDEN, 1904) I concluded the existence of a Caledonian Orogeny in the Himalaya, which was responsible for a different development of the Tibetan- and Lesser Himalaya (FUCHS, 1967). This idea was new and was not accepted by most geologists. In the following decades the importance of the Tertiary metamorphism was well substantiated and generally accepted (see LE FORT, 1975).
Most granites in the Crystalline, however, were dated as about 500 Ma. The interpretation of these Early Palaeozoic ages was that epirogenetic movements related with the Pan-African event have caused the granitic intrusions (LE FORT et al., 1986).
In recent years an increasing number of arguments for an Early Palaeozoic orogeny were proposed (FRANK et al., 1995; GEHRELS et al., 2003, 2006): Eoproterozoic-Ordovician metasediments were folded before the intrusion of the 500 Ma granites, related regional metamorphism reached at least garnet grade, exhumation and erosion of this complex followed. Further evidence is the angular unconformity in Spiti (HAYDEN, 1904), which was traced by all following workers in the Tethyan Zone of the NW-Himalaya. In my view the Ordovician Conglomerate correlates also with the Ralam Conglomerate between Martoli- and Garbyang Formations in Kumaun (FUCHS, 1967). Thus recent research substantiates my ideas proposed in 1967, but without reference to it.
BHARGAVA et al. (2011) suggest Early Palaeozoic thrust tectonics also in the Lesser Himalaya (Tons area). The thrust transport of ca 50 km, however, appears not convincing.
4. THE SOUTH TIBETAN DETACHMENT SYSTEM (STDS)
Since BURCHFIEL & ROYDEN (1985) discovered an extensional zone along the southern margin of the Tibetan Plateau many workers studied the STDS (see the references compiled by HODGES, 2000, p.338). I know personally the Sarchu- and Zanskar Faults in the NW-Himalaya, which belong to this system. There is a marked hiatus in the material and metamorphic grade on both sides of the faults, locally there is also cataclastic deformation. In maps the STDS is mostly shown as a continuous tectonic line. Actually it is a zone with faults on various levels replacing each other along the strike.
Apparently it has become a must among geologists to find the STDS, even in areas where it is not indicated by any observations. Mostly the STDS is assumed between the HHC and the Tethyan sedimentary sequence. In this way gradations and the primary connection of metamorphics and sediments are ignored. This was frequently the case at the base of the Dolpo-Manang Synclinorium, further in Kumaun, where GANSSER (1964) described passages, and in Spiti. The STDS is an extensional zone caused by differential movements of the Tibetan Plateau and the growing Himalaya. The sedimentary basins named above are part of the Himalayan block, thus the STDS is expected further N, in Nepal in the region N of Mustang-Palchung Hamga Himal.
6. ACKNOWLEDGEMENT
My colleague and friend Dr. Manfred Linner prepared my manuscript for digital publication. Many thanks for this and for fruitful discussions.
7. REFERENCES
ARITA, K., SHIRAISHI, K. & HAYASHI, D. (1984): Geology of Western Nepal and a Comparison with Kumaun, India. – J. Fac. Sci., Hokkaido Univ., Ser. IV, 21, 1-20, Hokkaido.
BHARGAVA, O.N., FRANK W. & BERTLE, R. (2011): Late Cambrian deformation in the Lesser Himalaya. – J. Asian Earth Sci., 40, 201-212, Amsterdam.
BURCHFIEL, B. C. & ROYDEN, L. H. (1985): North-south extension within the convergent Himalayan region. – Geology, 13, 679-682, Washington.
FUCHS, G. (1967): Zum Bau des Himalaya. – Denkschr. Österr. Akad. Wiss., math. naturwiss. Kl., 113, 211 S., Wien.
FUCHS, G. (1975): Contributions to the Geology of the North-Western Himalayas. – Abh. Geol. B.-A., 32, 59 S., Wien.
FUCHS, G. (1977): The Geology of the Karnali and Dolpo Regions, Western Nepal. – Jb. Geol. B.-A., 120, 165–217, Wien.
FUCHS, G. (1977a): Traverse of Zanskar from the Indus to the Valley of Kashmir – a preliminary note. – Jb. Geol. B.-A., 120, 219–229, Wien.
FUCHS, G. (1982): Geologic-Tectonic Map of the Himalaya 1:2,000,000. – Geol. B.-A., Wien.
FUCHS, G. & FRANK, W. (1970): The Geology of West Nepal between the Rivers Kali Gandaki and Thulo Bheri. – Jb. Geol. B.-A., Sdb. 18, 103 S., Wien.
FUCHS, G. & SINHA, A.K. (1978): The Tectonics of the Garhwal-Kumaun Lesser Himalaya. – Jb. Geol. B.-A., 121, 219–241, Wien.
FRANK, W., GRASEMANN, B., GUNTLI, P. & MILLER, Ch. (1995): Geological Map of the Kishtwar-Chamba-Kulu Region (NW Himalaya, India). – Jb. Geol. B.-A., 138, 299–308, Wien.
GANSSER, A. (1964): Geology of the Himalayas. - Interscience Publishers, 289 pp., London (John Wiley & Sons).
GEHRELS, G.E., DECELLES, P.G., MARTIN, A., OJHA, T.P., PINHASSI, G. & UPRETI, B.N. (2003): Initiation of the Himalayan Orogen as an Early Paleozoic thin-skinned Thrust Belt. – GSA Today, 13, 4-9, Boulder.
GEHRELS, G.E., DECELLES, P.G., OJHA, T.P. & UPRETI, B.N. (2006): Geologic and U-Pb geochronologic evidence for early Paleozoic tectonism in the Dadeldhura thrust sheet, far-west Nepal Himalaya. – J. Asian Earth Sci., 28, 385-408, Amsterdam.
HAGEN, T. (1969): Report on the Geological Survey of Nepal. Vol. 2: Geology of the Thakhola. – Denkschr. Schweiz. Naturforsch. Ges. 86, 1-185, Zürich.
HAYDEN, H.H. (1904): The Geology of Spiti, with parts of Bashahr and Rupshu. – Mem. Geol. Surv. India, 36, 1-129, Calcutta.
HODGES, K.V. (2000): Tectonics of the Himalaya and southern Tibet from two perspectives. – Geol. Soc. Am. Bull., 112, 324-350, Boulder.
LE FORT, P. (1975): Himalayas: The Collided Range. Present Knowledge of the Continental Arc. – Amer. J. Sci., 275-A, 1-44, New Haven.
LE FORT, P., DEBON, F., PÊCHER, A., SONET, J. & VIDAL, P. (1986): The 500 Ma magmatic event in alpine southern Asia, a thermal episode at Gondwana scale. – Mem. Sci. Terr., 47, 191-209, Nancy.
LYDEKKER, R. (1883): The Geology of the Kashmir and Chamba Territories and the British District of Khagan. – Mem. Geol. Surv. Ind., 22, 1-344, Calcutta.
SAKAI, H. (1983): Geology of the Tansen Group of the Lesser Himalaya in Nepal. – Mem. Fac. Sci. Kyoto Univ., Ser. D (Geology), 25, 27-74, Kyoto.
SAKAI, H. (1985): Geology of the Kali Gandaki Supergroup of the Lesser Himalaya in Nepal. – Mem. Fac. Sci. Kyoto Univ., Ser. D (Geology), 25, 337-397, Kyoto.
STÖCKLIN, J. (1980): Geology of the Nepal and its regional frame. – J. Geol. Soc. London, 137, 1-34, London.
UPRETI, B.N. (1995):The Lesser Himalayan Crystalline Nappes: Are they exotic slices? – J. Nepal Geol. Soc., 12, 10-12, Kathmandu.
UPRETI, B.N. (1996): Stratigraphy of the western Nepal Lesser Himalaya: A synthesis. – J. Nepal Geol. Soc., 13, 11-28, Kathmandu.
For decades there was dispute whether the unfossiliferous rock complex was Palaeozoic or Precambrian. On the basis of rare fossil finds and age data it is now generally accepted to be Precambrian to Early Cambrian (UPRETI, 1996; BHARGAVA et al., 2011).
In my view not yet settled is the correlation of the thick carbonate complexes of the Lesser Himalaya. SAKAI (1983), UPRETI (1996) and others regard the Kerabari and Krol Carbonates of the frontal zone (Parauthochtonous Unit, FUCHS, 1975) as Neoproterozoic. The Surtibang-, Dhading-, Shali-, and Deoban Carbonates of the inner zones are considered to be Midproterozoic (BHARGAVA et al., 2011). From the great lithological similarity and associated series a correlation of the two above named complexes should not be excluded.
Certainly a difficulty in the Stratigraphy is the confusion in nomenclature. Most authors introduce new names and their own scheme. My aim was to use the already existing and well-known terms like Chail, Shali, Krol etc from the type localities in India also in Nepal (FUCHS, 1967, 1977 and 1982; FUCHS & FRANK, 1970). These units can be traced along the Himalaya and are not confined by political borders. But my suggestion was not accepted.
Attempts have been made to subdivide the Kuncha-Chail complex by means of some conspicuous quartzite horizons (e.g. Fagfog Quartzite, STÖCKLIN, 1980). The quartzites, however, are of rather limited lateral extent. Thick conglomerate-quartzite bodies pass into pure phyllite series over a short distance along the strike. Probably they represent delta deposits and are not suitable for stratigraphical subdivision.
Closely connected with stratigraphy are tectonic problems. HAGEN (1969) proposed a complicated system of nappes. But he did not characterize their rock content and how they were discerned. The knowledge of the primary succession is necessary.
In the Hiunchuli region of West Nepal we found one of the rare occurrences where the stratigraphic order is still preserved (FUCHS & FRANK, 1970). Careful studies of the formation boundaries showed that they were stratigraphic, and the sedimentary structures indicated upright order. From bottom to top we find:
Green and white quartzites and phyllites (Chail, Kuncha).
Red and white quartzites and metapelites (Khaira, Nourpul).
Red and green slates and carbonates.
Black phyllites (Shali Slates, Benighat).
Blue and grey stromatolitic dolomites (Shali, Surtibang, Dhading).
This succession forms Chail Unit 1 (C1). After a thrust this sequence is repeated, but in reduced thickness W of Jangla Bhanjyang (C2), and above another thrust again phyllites and quartzites (Chail-Kuncha) follow representing C3. They are the topmost beds of the Lesser Himalaya immediately below the Main Central Thrust (MCT).
Towards the E the described successions pinch out and in the Kali Gandaki-Pokhara region we find only monotonous Kuncha-Chail Formation of vast extent. Carbonate marker horizons appear again in the Nawakot Complex W of the Kathmandu-Synclinorium (STÖCKLIN, 1980, map). These carbonates indicate thrusts at their top and make it probable that such tectonic planes exist also where the Chail-Kuncha rocks seem to form a uniform complex.
There are also authors who deny nappes in the Lesser Himalaya (ARITA et al., 1984). They accept the crystalline outliers as allochthonous, but the underlying Midland complex they take as autochthonous, affected only by vertical movements. That implies that the succession observed in the latter is stratigraphic. This assumption is disproved by our work (FUCHS, 1977) in the Galwa Window (HAGEN, 1969). In the core of this large dome we find stromatolitic dolomite with varicoloured carbonates and metapelites (C1). This unit is overthrust by Kuncha-Chail Formation succeeded by varicoloured conglomerates and quarzites, which in turn are overlain by thick dolomite (C2). Above another thrust Kuncha-Chail Formation follows (C3) forming the top of the Lesser Himalayan sequence under the MCT (FUCHS, 1977, Plate 1). The lowest of these units (C1) may be autochthonous, the upper units definitely are nappes (C2, C3); dragged by the overthrusting Crystalline Nappes the C3 shows the largest width of transport with outliers on the Mahabharat Range (S of Daban, Phalabang; FUCHS & FRANK, 1970, Plate 1). C3 has also wide extent in Ranimatta-Dailekh area N of Surkhet (FUCHS, 1977, Plate 1). The quartzites, phyllites and metabasics of the Kuncha-Chail Formation are also accompanied by granites. The latter intruded the Chails and are frequent in the Western Himalaya. Their ages cluster around 1800 Ma (FRANK et al., 1995).
Another problem is the Krol belt – is it a nappe or a frontal folded wedge of the Lesser Himalaya? I have introduced the term Parautochthonous Unit for it. It overthrusts the Tertiary Zone along the Main Boundary Thrust (MBT), but always has formed the southernmost part of the Lesser Himalaya. The frequent occurrence of Gondwana and Tertiary beds shows its proximity to the Indian Craton (Garhwal-, Tansing Synclines). There are no outliers or relics of a “Krol Nappe” N of the frontal range, at the base of the Crystalline klippes or the MCT. The superposition of the Chail Nappes is evident from the outliers of Satengal, Banali, Lansdowne and the Mahabharat Range (FUCHS & FRANK, 1970; FUCHS & SINHA, 1978). The Parautochthonous Unit is not metamorphosed or of only low grade. The assumption of a Krol Nappe implies that this unit would be intercalated between the greenschist metamorphosed Midland complex (Chail Nappes) and the amphibolite facies grade Crystalline Nappes. This was nowhere observed, rather an increase in metamorphic grade from lower to upper structural units (inverse metamorphism). Thus I regard the Krol belt as a folded wedge zone in the frontal part of the Lesser Himalaya.
2. CORRELATION CENTRAL CRYSTALLINE - CRYSTALLINE OUTLIERS
UPRETI (1995) hesitates to accept the Central Crystalline as a root zone of the crystalline klippes in the Lesser Himalaya, because of a series of differences.
Contrary I should like to stress that in eastern Nepal and Sikkim the root zone is still connected with the frontal parts of the Crystalline Nappe. In the western Himalaya the Crystalline Nappes with their sedimentary cover – the Kashmir and Chamba Synclinoria – can be traced to their roots in the High Himalaya Crystalline (HHC). It can be observed there that the highly migmatized gneiss complex becomes reduced towards the south and is replaced by less metamorphosed Salkalas. If we consider that the frontal portions of the Crystalline Nappe have been exposed to cooling when rocks of the root zone were still in the center of the regional metamorphism, differences are easily explained. Further it is a common experience that the basal portions of a nappe are frequently kept back by friction and the upper beds are enriched in the frontal parts (e.g. Kashmir Nappe). This may account for the smaller thickness of the gneiss-migmatite complex in the klippes.
Differences in the facies of the basal Tethyan sedimentary cover of the klippes (e.g. Kathmandu, Jaljala Dhuri) to the Tethyan Zone are explained by the fact that there are also facies changes within the Tethyan Zone. From the Nilgiri in the E to Kanjiroba in the W the silt content increases considerably. Similar changes in N-S direction can not be excluded.
Thus I see no necessity to introduce the term Mahabharat Thrust (UPRETI, 1995) at the base of the Kathmandu Klippe. We may safely take it as the MCT.
3. EARLY PALAEOZOIC OROGENY
At the beginning of my research in Nepal (FUCHS, 1967) I recognized the gradation from the Central Crystalline into the Cambro-Ordovician sediments of the Tibetan Zone by passing away of the metamorphism. Further I found a significant break in the sedimentary development at the Ordovician-Silurian boundary: Continental slope sedimentation (as we would say today) changed to a variety of platform facies. In context with the Ordovician unconformity in the W Himalaya (HAYDEN, 1904) I concluded the existence of a Caledonian Orogeny in the Himalaya, which was responsible for a different development of the Tibetan- and Lesser Himalaya (FUCHS, 1967). This idea was new and was not accepted by most geologists. In the following decades the importance of the Tertiary metamorphism was well substantiated and generally accepted (see LE FORT, 1975).
Most granites in the Crystalline, however, were dated as about 500 Ma. The interpretation of these Early Palaeozoic ages was that epirogenetic movements related with the Pan-African event have caused the granitic intrusions (LE FORT et al., 1986).
In recent years an increasing number of arguments for an Early Palaeozoic orogeny were proposed (FRANK et al., 1995; GEHRELS et al., 2003, 2006): Eoproterozoic-Ordovician metasediments were folded before the intrusion of the 500 Ma granites, related regional metamorphism reached at least garnet grade, exhumation and erosion of this complex followed. Further evidence is the angular unconformity in Spiti (HAYDEN, 1904), which was traced by all following workers in the Tethyan Zone of the NW-Himalaya. In my view the Ordovician Conglomerate correlates also with the Ralam Conglomerate between Martoli- and Garbyang Formations in Kumaun (FUCHS, 1967). Thus recent research substantiates my ideas proposed in 1967, but without reference to it.
BHARGAVA et al. (2011) suggest Early Palaeozoic thrust tectonics also in the Lesser Himalaya (Tons area). The thrust transport of ca 50 km, however, appears not convincing.
4. THE SOUTH TIBETAN DETACHMENT SYSTEM (STDS)
Since BURCHFIEL & ROYDEN (1985) discovered an extensional zone along the southern margin of the Tibetan Plateau many workers studied the STDS (see the references compiled by HODGES, 2000, p.338). I know personally the Sarchu- and Zanskar Faults in the NW-Himalaya, which belong to this system. There is a marked hiatus in the material and metamorphic grade on both sides of the faults, locally there is also cataclastic deformation. In maps the STDS is mostly shown as a continuous tectonic line. Actually it is a zone with faults on various levels replacing each other along the strike.
Apparently it has become a must among geologists to find the STDS, even in areas where it is not indicated by any observations. Mostly the STDS is assumed between the HHC and the Tethyan sedimentary sequence. In this way gradations and the primary connection of metamorphics and sediments are ignored. This was frequently the case at the base of the Dolpo-Manang Synclinorium, further in Kumaun, where GANSSER (1964) described passages, and in Spiti. The STDS is an extensional zone caused by differential movements of the Tibetan Plateau and the growing Himalaya. The sedimentary basins named above are part of the Himalayan block, thus the STDS is expected further N, in Nepal in the region N of Mustang-Palchung Hamga Himal.
6. ACKNOWLEDGEMENT
My colleague and friend Dr. Manfred Linner prepared my manuscript for digital publication. Many thanks for this and for fruitful discussions.
7. REFERENCES
ARITA, K., SHIRAISHI, K. & HAYASHI, D. (1984): Geology of Western Nepal and a Comparison with Kumaun, India. – J. Fac. Sci., Hokkaido Univ., Ser. IV, 21, 1-20, Hokkaido.
BHARGAVA, O.N., FRANK W. & BERTLE, R. (2011): Late Cambrian deformation in the Lesser Himalaya. – J. Asian Earth Sci., 40, 201-212, Amsterdam.
BURCHFIEL, B. C. & ROYDEN, L. H. (1985): North-south extension within the convergent Himalayan region. – Geology, 13, 679-682, Washington.
FUCHS, G. (1967): Zum Bau des Himalaya. – Denkschr. Österr. Akad. Wiss., math. naturwiss. Kl., 113, 211 S., Wien.
FUCHS, G. (1975): Contributions to the Geology of the North-Western Himalayas. – Abh. Geol. B.-A., 32, 59 S., Wien.
FUCHS, G. (1977): The Geology of the Karnali and Dolpo Regions, Western Nepal. – Jb. Geol. B.-A., 120, 165–217, Wien.
FUCHS, G. (1977a): Traverse of Zanskar from the Indus to the Valley of Kashmir – a preliminary note. – Jb. Geol. B.-A., 120, 219–229, Wien.
FUCHS, G. (1982): Geologic-Tectonic Map of the Himalaya 1:2,000,000. – Geol. B.-A., Wien.
FUCHS, G. & FRANK, W. (1970): The Geology of West Nepal between the Rivers Kali Gandaki and Thulo Bheri. – Jb. Geol. B.-A., Sdb. 18, 103 S., Wien.
FUCHS, G. & SINHA, A.K. (1978): The Tectonics of the Garhwal-Kumaun Lesser Himalaya. – Jb. Geol. B.-A., 121, 219–241, Wien.
FRANK, W., GRASEMANN, B., GUNTLI, P. & MILLER, Ch. (1995): Geological Map of the Kishtwar-Chamba-Kulu Region (NW Himalaya, India). – Jb. Geol. B.-A., 138, 299–308, Wien.
GANSSER, A. (1964): Geology of the Himalayas. - Interscience Publishers, 289 pp., London (John Wiley & Sons).
GEHRELS, G.E., DECELLES, P.G., MARTIN, A., OJHA, T.P., PINHASSI, G. & UPRETI, B.N. (2003): Initiation of the Himalayan Orogen as an Early Paleozoic thin-skinned Thrust Belt. – GSA Today, 13, 4-9, Boulder.
GEHRELS, G.E., DECELLES, P.G., OJHA, T.P. & UPRETI, B.N. (2006): Geologic and U-Pb geochronologic evidence for early Paleozoic tectonism in the Dadeldhura thrust sheet, far-west Nepal Himalaya. – J. Asian Earth Sci., 28, 385-408, Amsterdam.
HAGEN, T. (1969): Report on the Geological Survey of Nepal. Vol. 2: Geology of the Thakhola. – Denkschr. Schweiz. Naturforsch. Ges. 86, 1-185, Zürich.
HAYDEN, H.H. (1904): The Geology of Spiti, with parts of Bashahr and Rupshu. – Mem. Geol. Surv. India, 36, 1-129, Calcutta.
HODGES, K.V. (2000): Tectonics of the Himalaya and southern Tibet from two perspectives. – Geol. Soc. Am. Bull., 112, 324-350, Boulder.
LE FORT, P. (1975): Himalayas: The Collided Range. Present Knowledge of the Continental Arc. – Amer. J. Sci., 275-A, 1-44, New Haven.
LE FORT, P., DEBON, F., PÊCHER, A., SONET, J. & VIDAL, P. (1986): The 500 Ma magmatic event in alpine southern Asia, a thermal episode at Gondwana scale. – Mem. Sci. Terr., 47, 191-209, Nancy.
LYDEKKER, R. (1883): The Geology of the Kashmir and Chamba Territories and the British District of Khagan. – Mem. Geol. Surv. Ind., 22, 1-344, Calcutta.
SAKAI, H. (1983): Geology of the Tansen Group of the Lesser Himalaya in Nepal. – Mem. Fac. Sci. Kyoto Univ., Ser. D (Geology), 25, 27-74, Kyoto.
SAKAI, H. (1985): Geology of the Kali Gandaki Supergroup of the Lesser Himalaya in Nepal. – Mem. Fac. Sci. Kyoto Univ., Ser. D (Geology), 25, 337-397, Kyoto.
STÖCKLIN, J. (1980): Geology of the Nepal and its regional frame. – J. Geol. Soc. London, 137, 1-34, London.
UPRETI, B.N. (1995):The Lesser Himalayan Crystalline Nappes: Are they exotic slices? – J. Nepal Geol. Soc., 12, 10-12, Kathmandu.
UPRETI, B.N. (1996): Stratigraphy of the western Nepal Lesser Himalaya: A synthesis. – J. Nepal Geol. Soc., 13, 11-28, Kathmandu.
PhD position on kinetic isotope effect in atmospheric VOC oxidation
Within the Helmholtz graduate school HITEC we are calling for applications for the following PhD project:
On the temperature dependence of the kinetic isotope effect
Stable carbon isotopic analyses, complementary to concentration measurements, are effective tools for characterizing the sources of volatile organic compounds (VOCs) and understanding the processes governing their distribution in the atmosphere. The average physical age of an individual VOC in the atmosphere can be determined from the observed isotopic composition, when the source isotopic composition of the VOC and the kinetic isotope effect (KIE) of oxidation reactions involved in the atmospheric VOC degradation are known. A recent pilot study showed that below 273K KIE increases. Applying temperature dependent KIE has significant impacts on the interpretation of ambient observations.
In this project the KIE will be investigated as function of temperature. To this end the successful candidate will plan and conduct experiments of VOC oxidation, apply isotope mass spectrometry and interpret results with the help of chemical models. Laboratory findings will be complemented by measurements in the atmosphere. The results of this project will contribute to advance process understanding in atmospheric chemistry. The use of stable isotopes for process understanding in atmospheric research is a highly innovative field.
Requirements: Master degree (or equivalent) in Chemistry, Physics, or Atmospheric Science; Very good experimental skills; experience in physical chemistry and/or isotope mass spectrometry are helpful
For further information see:
http://www.fz-juelich.de/portal/DE/Leistungen/WissenWeitergeben/hitec/ausschreibungen.html
Or contact: PD Dr. Astrid Kiendler-Scharr A.kiendler-scharr@fz-juelich.de
Please submit your electronic application to: B.koester@fz-juelich.de
On the temperature dependence of the kinetic isotope effect
Stable carbon isotopic analyses, complementary to concentration measurements, are effective tools for characterizing the sources of volatile organic compounds (VOCs) and understanding the processes governing their distribution in the atmosphere. The average physical age of an individual VOC in the atmosphere can be determined from the observed isotopic composition, when the source isotopic composition of the VOC and the kinetic isotope effect (KIE) of oxidation reactions involved in the atmospheric VOC degradation are known. A recent pilot study showed that below 273K KIE increases. Applying temperature dependent KIE has significant impacts on the interpretation of ambient observations.
In this project the KIE will be investigated as function of temperature. To this end the successful candidate will plan and conduct experiments of VOC oxidation, apply isotope mass spectrometry and interpret results with the help of chemical models. Laboratory findings will be complemented by measurements in the atmosphere. The results of this project will contribute to advance process understanding in atmospheric chemistry. The use of stable isotopes for process understanding in atmospheric research is a highly innovative field.
Requirements: Master degree (or equivalent) in Chemistry, Physics, or Atmospheric Science; Very good experimental skills; experience in physical chemistry and/or isotope mass spectrometry are helpful
For further information see:
http://www.fz-juelich.de/portal/DE/Leistungen/WissenWeitergeben/hitec/ausschreibungen.html
Or contact: PD Dr. Astrid Kiendler-Scharr A.kiendler-scharr@fz-juelich.de
Please submit your electronic application to: B.koester@fz-juelich.de
Friday, January 13, 2012
FIELD GEOLOGISTS: VACANCY AT CASP
If you love fieldwork and the great outdoors, are looking for a friendly and flexible
working environment and relish stimulating academic discussions and challenges,
this may be the opportunity for you.
CASP is a geological research organisation that is affiliated to the Department of Earth Sciences at the University of Cambridge. Funded almost entirely by the international hydrocarbon industry, CASP is widely valued by its sponsors for combining original field-based research in remote areas with innovative regional synthesis.
We are seeking to recruit a motivated field geologist with a broad geological background and an ability to investigate the evolution of sedimentary basins from a structural view point.
Candidates will have completed a PhD and preferably a period of post-doctoral research. Applicants should be enthusiastic field geologists ready to carry out fieldwork in Greenland and potentially areas as diverse as the Arctic, Russia, North Africa or the Middle East.
This permanent position requires the ability to work in a team, to interact with academic and industry contacts, and to take responsibility for project and research development. As well as writing reports for company sponsors, all CASP geologists are required to present their results at workshops and conferences and are strongly encouraged to publish their research and develop/maintain an academic profile.
Salaries are broadly in line with the University of Cambridge scales (Grades 7-8) and include additional benefits. For further details about CASP, please visit: www.casp.cam.ac.uk
Please send a CV (naming 2 referees) and a covering letter explaining your motivation to tina.walker@casp.cam.ac.uk
working environment and relish stimulating academic discussions and challenges,
this may be the opportunity for you.
CASP is a geological research organisation that is affiliated to the Department of Earth Sciences at the University of Cambridge. Funded almost entirely by the international hydrocarbon industry, CASP is widely valued by its sponsors for combining original field-based research in remote areas with innovative regional synthesis.
We are seeking to recruit a motivated field geologist with a broad geological background and an ability to investigate the evolution of sedimentary basins from a structural view point.
Candidates will have completed a PhD and preferably a period of post-doctoral research. Applicants should be enthusiastic field geologists ready to carry out fieldwork in Greenland and potentially areas as diverse as the Arctic, Russia, North Africa or the Middle East.
This permanent position requires the ability to work in a team, to interact with academic and industry contacts, and to take responsibility for project and research development. As well as writing reports for company sponsors, all CASP geologists are required to present their results at workshops and conferences and are strongly encouraged to publish their research and develop/maintain an academic profile.
Salaries are broadly in line with the University of Cambridge scales (Grades 7-8) and include additional benefits. For further details about CASP, please visit: www.casp.cam.ac.uk
Please send a CV (naming 2 referees) and a covering letter explaining your motivation to tina.walker@casp.cam.ac.uk
Wednesday, January 11, 2012
Hydropower in Nepal
URL: http://www.ippan.org.np/HPinNepal.html
Nepal has a huge hydropower potential. In fact, the perennial nature of Nepali rivers and the steep gradient of the country's topography provide ideal conditions for the development of some of the world's largest hydroelectric projects in Nepal. Current estimates are that Nepal has approximately 40,000 MW of economically feasible hydropower potential. However, the present situation is that Nepal has developed only approximately 600 MW of hydropower. Therefore, bulk of the economically feasible generation has not been realized yet. Besides, the multipurpose, secondary and tertiary benefits have not been realized from the development of its rivers.
Although bestowed with tremendous hydropower resources, only about 40% of Nepal's population has access to electricity. Most of the power plants in Nepal are run-of-river type with energy available in excess of the in-country demand during the monsoon season and deficit during the dry season.
Nepal's electricity generation is dominated by hydropower, though in the entire scenario of energy use of the country, the electricity is a tiny fraction, only 1% energy need is fulfilled by electricity. The bulk of the energy need is dominated by fuel wood (68%), agricultural waste (15%), animal dung (8%) and imported fossil fuel (8%). The other fact is that only about 40% of Nepal's population has access to electricity. With this scenario and having immense potential of hydropower development, it is important for Nepal to increase its energy dependency on electricity with hydropower development. This contributes to deforestation, soil erosion and depletion, and increased flooding downstream in the Ganges plain. Shortage of wood also pushes farmers to burn animal dung, which is needed for agriculture. Not only this, the development of hydropower will help to achieve the millennium development goals with protecting environment, increasing literacy, improving health of children and women with better energy. Growing environmental degradation adds a sense of urgency.
Nepal has a huge hydropower potential. In fact, the perennial nature of Nepali rivers and the steep gradient of the country's topography provide ideal conditions for the development of some of the world's largest hydroelectric projects in Nepal. Current estimates are that Nepal has approximately 40,000 MW of economically feasible hydropower potential. However, the present situation is that Nepal has developed only approximately 600 MW of hydropower. Therefore, bulk of the economically feasible generation has not been realized yet. Besides, the multipurpose, secondary and tertiary benefits have not been realized from the development of its rivers.
Although bestowed with tremendous hydropower resources, only about 40% of Nepal's population has access to electricity. Most of the power plants in Nepal are run-of-river type with energy available in excess of the in-country demand during the monsoon season and deficit during the dry season.
Nepal's electricity generation is dominated by hydropower, though in the entire scenario of energy use of the country, the electricity is a tiny fraction, only 1% energy need is fulfilled by electricity. The bulk of the energy need is dominated by fuel wood (68%), agricultural waste (15%), animal dung (8%) and imported fossil fuel (8%). The other fact is that only about 40% of Nepal's population has access to electricity. With this scenario and having immense potential of hydropower development, it is important for Nepal to increase its energy dependency on electricity with hydropower development. This contributes to deforestation, soil erosion and depletion, and increased flooding downstream in the Ganges plain. Shortage of wood also pushes farmers to burn animal dung, which is needed for agriculture. Not only this, the development of hydropower will help to achieve the millennium development goals with protecting environment, increasing literacy, improving health of children and women with better energy. Growing environmental degradation adds a sense of urgency.
PhD Scholarship Opportunities
PhD research scholarship opportunities are now available in the Connected Waters Initiative Research Centre, University of New South Wales(UNSW). We are looking for dedicated, well-motivated and enthusiastic students interested in climate-surface-ground water interactions.
At UNSW, an extensive range of research facilities are available to students via the UNSW Analytical Centre, as well as specialised facilities such as stable isotope mass spectrometers, a geotechnical centrifuge for investigating aquitard hydrology, high-performance computer modelling and access to extensive field-based borehole and climate monitoring infrastructure. PhD students would be expected to take the opportunity of affiliating to the National Centre for Groundwater Research and Training (NCGRT), a multimillion dollar investment into groundwater research and training in Australia. Additional top-up scholarships are available from the NCGRT.
Projects are available in a wide range of fields, including:
Characterising fractured rock systems
Heat as a tracer for groundwater flow
Combining multiple tracers in ground and surface water interaction
Novel application of stable isotopes in the hydrological cycle
Stalagmite proxies of paleo groundwater recharge and paleoclimate
Characterising specific storage in silts and clays using seismic and gravity methods
Aquitard hydrology at accelerated gravity
Computational geoscience
Modelling the impact aquifer heterogeneity
Cellular automata modelling of eco-hydrological dynamics
Remote sensing of the hydrological system
Coupled groundwater-surface-vegetation-atmosphere modelling
Heat as a tracer in highly karstified aquifers
More specific information about the Connected Waters Initiative Research Centre can be found at: http://www.connectedwaters.unsw.edu.au
International and Domestic students of exceptional quality can apply now for scholarships at: http://research.unsw.edu.au/international-research-candidate-scholarships.
And:
http://research.unsw.edu.au/domestic-research-candidate-scholarships
Closing date for both schemes is 2nd March 2012 for a PhD start date in mid-2012.
Successful PhD applicants must hold a 4-year Bachelor's degree with Honours class 1, or their equivalent, and must demonstrate relevant additional research experience or prizes for academic excellence. Research publications in international journals will provide strong support for scholarship applications. All successful applications would be eligible for an additional NCGRT scholarship.
International applicants must demonstrate their eligibility for scholarships: details can be found at:
http://research.unsw.edu.au/sites/all/files/related_files/regular_page_content/international_scholarship_guidelines.pdf.
For further information on the PhD projects and the scholarships available, please contact Prof. Andy Baker (unsw12011@earthworks-jobs.com), attaching your cv and evidence of eligibility.
At UNSW, an extensive range of research facilities are available to students via the UNSW Analytical Centre, as well as specialised facilities such as stable isotope mass spectrometers, a geotechnical centrifuge for investigating aquitard hydrology, high-performance computer modelling and access to extensive field-based borehole and climate monitoring infrastructure. PhD students would be expected to take the opportunity of affiliating to the National Centre for Groundwater Research and Training (NCGRT), a multimillion dollar investment into groundwater research and training in Australia. Additional top-up scholarships are available from the NCGRT.
Projects are available in a wide range of fields, including:
Characterising fractured rock systems
Heat as a tracer for groundwater flow
Combining multiple tracers in ground and surface water interaction
Novel application of stable isotopes in the hydrological cycle
Stalagmite proxies of paleo groundwater recharge and paleoclimate
Characterising specific storage in silts and clays using seismic and gravity methods
Aquitard hydrology at accelerated gravity
Computational geoscience
Modelling the impact aquifer heterogeneity
Cellular automata modelling of eco-hydrological dynamics
Remote sensing of the hydrological system
Coupled groundwater-surface-vegetation-atmosphere modelling
Heat as a tracer in highly karstified aquifers
More specific information about the Connected Waters Initiative Research Centre can be found at: http://www.connectedwaters.unsw.edu.au
International and Domestic students of exceptional quality can apply now for scholarships at: http://research.unsw.edu.au/international-research-candidate-scholarships.
And:
http://research.unsw.edu.au/domestic-research-candidate-scholarships
Closing date for both schemes is 2nd March 2012 for a PhD start date in mid-2012.
Successful PhD applicants must hold a 4-year Bachelor's degree with Honours class 1, or their equivalent, and must demonstrate relevant additional research experience or prizes for academic excellence. Research publications in international journals will provide strong support for scholarship applications. All successful applications would be eligible for an additional NCGRT scholarship.
International applicants must demonstrate their eligibility for scholarships: details can be found at:
http://research.unsw.edu.au/sites/all/files/related_files/regular_page_content/international_scholarship_guidelines.pdf.
For further information on the PhD projects and the scholarships available, please contact Prof. Andy Baker (unsw12011@earthworks-jobs.com), attaching your cv and evidence of eligibility.
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