bluuebunny/crossref_metadata_2025 huggingface dataset:
Tobacco Mosaic VirusReplicase-Auxin/Indole Acetic Acid Protein Interactions: Reprogramming the Auxin Response Pathway To Enhance Virus Infection
Authors: Padmanabhan Meenu S. , Kramer Sabrina R. , Wang Xiao , Culver James N.
Published: December 2007

The replicase protein ofTobacco mosaic virus(TMV) disrupts the localization and stability of interacting auxin/indole acetic acid (Aux/IAA) proteins inArabidopsis, altering auxin-mediated gene regulation and promoting disease development (M. S. Padmanabhan, S. P. Goregaoker, S. Golem, H. Shiferaw, and J. N. Culver, J. Virol. 79:2549-2558, 2005). In this study, a similar replicase-Aux/IAA interaction affecting disease development was identified in tomato. The ability of the TMV replicase to interact with Aux/IAA proteins from diverse hosts suggests that these interactions contribute to the infection process. To examine the role of this interaction in virus pathogenicity, the replication and spread of a TMV mutant with a reduced ability to interact with specific Aux/IAA proteins were examined. Within young (4- to 6-week-old) leaf tissue, there were no significant differences in the abilities of Aux/IAA-interacting or -noninteracting viruses to replicate and spread. In contrast, in mature (10- to 12-week-old) leaf tissue, the inability to interact with specific Aux/IAA proteins correlated with a significant reduction in virus accumulation. Correspondingly, interacting Aux/IAA levels are significantly higher in older tissue and the overaccumulation of a degradation-resistant Aux/IAA protein reduced virus accumulation in young leaf tissue. Combined, these findings suggest that TMV replicase-Aux/IAA interactions selectively enhance virus pathogenicity in tissues where Aux/IAA proteins accumulate. We speculate that the virus disrupts Aux/IAA functions as a means to reprogram the cellular environment of older cells to one that is more compatible for virus replication and spread.
Pseudodiploid Genome Organization Aids Full-Length Human Immunodeficiency Virus Type 1 DNA Synthesis
Authors: King Steven R. , Duggal Nisha K. , Ndongmo Clement B. , Pacut Crystal , Telesnitsky Alice
Published: December 2007

Template switching between copackaged human immunodeficiency virus type 1 (HIV-1) genomic RNAs is genetically silent when identical RNAs are copackaged but yields recombinants when virions contain two distinct RNAs. Sequencing has revealed that errors at retroviral recombination junctions are infrequent, suggesting that template switching is not intrinsically mutagenic. Here, we tested the hypothesis that template switching may instead contribute to replication fidelity. This hypothesis predicts that reverse transcription of a single-copy gene will be more error prone than replication in the presence of a second copy. To test this, HIV-1-based vectors containing both
lacZ
and the puromycin resistance marker were expressed either alone or with an excess of an “empty” vector lacking
lacZ
and
puro
. This resulted in virions with either RNA homodimers or haploid genomes with only a single
lacZ-puro
RNA. In untreated cells,
lacZ
inactivation rates suggested that haploid vector reverse transcription was slightly more error prone than that of homodimerized pseudodiploid vectors. Haploid reverse transcription was at least threefold more error prone than pseudodiploid-templated synthesis when slowed by hydroxyurea treatment or stopped prematurely with zidovudine. Individual products of one- and two-copy genes revealed both nucleotide substitutions and deletions, with deletions more frequent than point mutations among haploid genome products. Similar spectra of defective products were observed at early reverse transcription time points and among products of haploid virions. These results indicate that faithful, full-length reverse transcription products were underrepresented in the absence of a reserve of genetic information and suggest that template switching contributes to HIV-1 genomic integrity.
Structures of Two Coronavirus Main Proteases: Implications for Substrate Binding and Antiviral Drug Design
Authors: Xue Xiaoyu , Yu Hongwei , Yang Haitao , Xue Fei , Wu Zhixin , Shen Wei , Li Jun , Zhou Zhe , Ding Yi , Zhao Qi , Zhang Xuejun C. , Liao Ming , Bartlam Mark , Rao Zihe
Published: December 2007

Coronaviruses (CoVs) can infect humans and multiple species of animals, causing a wide spectrum of diseases. The coronavirus main protease (M
pro
), which plays a pivotal role in viral gene expression and replication through the proteolytic processing of replicase polyproteins, is an attractive target for anti-CoV drug design. In this study, the crystal structures of infectious bronchitis virus (IBV) M
pro
and a severe acute respiratory syndrome CoV (SARS-CoV) M
pro
mutant (H41A), in complex with an N-terminal autocleavage substrate, were individually determined to elucidate the structural flexibility and substrate binding of M
pro
. A monomeric form of IBV M
pro
was identified for the first time in CoV M
pro
structures. A comparison of these two structures to other available M
pro
structures provides new insights for the design of substrate-based inhibitors targeting CoV M
pro
s. Furthermore, a Michael acceptor inhibitor (named N3) was cocrystallized with IBV M
pro
and was found to demonstrate in vitro inactivation of IBV M
pro
and potent antiviral activity against IBV in chicken embryos. This provides a feasible animal model for designing wide-spectrum inhibitors against CoV-associated diseases. The structure-based optimization of N3 has yielded two more efficacious lead compounds, N27 and H16, with potent inhibition against SARS-CoV M
pro
.
Transdominant Inhibition of Bovine Viral Diarrhea Virus Entry
Authors: Tscherne Donna M. , Evans Matthew J. , MacDonald Margaret R. , Rice Charles M.
Published: December 2007

Bovine viral diarrhea virus
(BVDV) is a positive-strand RNA virus and a member of the genus
Pestivirus
in the family
Flaviviridae
. To identify and characterize essential factors required for BVDV replication, a library expressing random fragments of the BVDV genome was screened for sequences that act as transdominant inhibitors of viral replication by conferring resistance to cytopathic BVDV-induced cell death. We isolated a BVDV-nonpermissive MDBK cell clone that harbored a 1.2-kb insertion spanning the carboxy terminus of the envelope glycoprotein 1 (E1), the envelope glycoprotein E2, and the amino terminus of p7. Confirming the resistance phenotype conferred by this library clone, naïve MDBK cells expressing this fragment were found to be 100- to 1,000-fold less permissive to both cytopathic and noncytopathic BVDV infection compared to parental MDBK cells, although these cells remained fully permissive to vesicular stomatitis virus. This restriction could be overcome by electroporation of BVDV RNA, indicating a block at one or more steps in viral entry prior to translation of the viral RNA. We determined that the E2 ectodomain was responsible for the inhibition to BVDV entry and that this block occurred downstream from BVDV interaction with the cellular receptor CD46 and virus binding, suggesting interference with a yet-unidentified BVDV entry factor.
A Single-Amino-Acid Substitution in the Tvb
S1
Receptor Results in Decreased Susceptibility to Infection by Avian Sarcoma and Leukosis Virus Subgroups B and D and Resistance to Infection by Subgroup E In Vitro and In Vivo
Authors: Reinišová Markéta , Šenigl Filip , Yin Xueqian , Plachý Jiří , Geryk Josef , Elleder Daniel , Svoboda Jan , Federspiel Mark J. , Hejnar Jiří
Published: December 2007

The avian sarcoma and leukosis virus (ASLV) family of retroviruses contains five highly related envelope subgroups (A to E) thought to have evolved from a common viral ancestor in the chicken population. Three genetic loci in chickens determine the susceptibility or resistance of cells to infection by the subgroup A to E ASLVs. Some inbred lines of chickens display phenotypes that are somewhere in between either efficiently susceptible or resistant to infection by specific subgroups of ASLV. The
tvb
gene encodes the receptor for subgroups B, D, and E ASLVs. The wild-type Tvb
S1
receptor confers susceptibility to subgroups B, D, and E ASLVs. In this study, the genetic defect that accounts for the altered susceptibility of an inbred chicken line, line M, to infection by ASLV(B), ASLV(D), and ASLV(E) was identified. The
tvb
gene in line M,
tvb

r2

, encodes a mutant Tvb
S1
receptor protein with a substitution of a serine for a cysteine at position 125 (C125S). Here, we show that the C125S substitution in Tvb
S1
significantly reduces the susceptibility of line M cells to infection by ASLV(B) and ASLV(D) and virtually eliminates susceptibility to ASLV(E) infection both in cultured cells and in the incidence and growth of avian sarcoma virus-induced sarcomas in chickens. The C125S substitution significantly reduces the binding affinity of the Tvb
S1
receptor for the subgroup B, D, and E ASLV envelope glycoproteins. These are the first results that demonstrate a possible role of the cysteine-rich domain 3 in the function of the Tvb receptors.
Molecular Characterization of Feline Immunodeficiency Virus Budding
Authors: Luttge Benjamin G. , Shehu-Xhilaga Miranda , Demirov Dimiter G. , Adamson Catherine S. , Soheilian Ferri , Nagashima Kunio , Stephen Andrew G. , Fisher Robert J. , Freed Eric O.
Published: December 2007

Infection of domestic cats with feline immunodeficiency virus (FIV) is an important model system for studying human immunodeficiency virus type 1 (HIV-1) infection due to numerous similarities in pathogenesis induced by these two lentiviruses. However, many molecular aspects of FIV replication remain poorly understood. It is well established that retroviruses use short peptide motifs in Gag, known as late domains, to usurp cellular endosomal sorting machinery and promote virus release from infected cells. For example, the Pro-Thr/Ser-Ala-Pro [P(T/S)AP] motif of HIV-1 Gag interacts directly with Tsg101, a component of the endosomal sorting complex required for transport I (ESCRT-I). A Tyr-Pro-Asp-Leu (YPDL) motif in equine infectious anemia virus (EIAV), and a related sequence in HIV-1, bind the endosomal sorting factor Alix. In this study we sought to identify and characterize FIV late domain(s) and elucidate cellular machinery involved in FIV release. We determined that mutagenesis of a PSAP motif in FIV Gag, small interfering RNA-mediated knockdown of Tsg101 expression, and overexpression of a P(T/S)AP-binding fragment of Tsg101 (TSG-5′) each inhibited FIV release. We also observed direct binding of FIV Gag peptides to Tsg101. In contrast, mutagenesis of a potential Alix-binding motif in FIV Gag did not affect FIV release. Similarly, expression of the HIV-1/EIAV Gag-binding domain of Alix (Alix-V) did not disrupt FIV budding, and FIV Gag peptides showed no affinity for Alix-V. Our data demonstrate that FIV relies predominantly on a Tsg101-binding PSAP motif in the C terminus of Gag to promote virus release in HeLa cells, and this budding mechanism is highly conserved in feline cells.
More thoughts on the automobility of the graptolites
Authors: KIRK NANCY HARTSHORNE
Published: December 2007

S
ince
it was first suggested by
Lapworth (1897)
it has been generally accepted that the Graptoloids evolved from a form of
Dictyonema,
with a long, thread-like nema, in which ‘the pendent mode of attachment is the only one possible’. I disputed this (
Kirk 1969
) suggesting that if ciliary feeding currents had been drawn towards the thecae, a
Dictyonema
of this kind could have been maintained in an
upright
position on a nema attached distally to the sea floor, and that it could have become detached and independently moving as an adult, so accounting for its ubiquitous distribution. Starting from such an
upright
rhabdosome I attempted to show how the graptoloids might have evolved into a great variety of independently moving forms in which the sicula always opened upwards, thus obviating the necessity for explaining the unlikely reversion from pendent, through reclined, back to upright or scandent, and also the difficulty of attaching many of the forms
to floating
seaweed of which the existence was highly questionable.

In the discussion of this thesis, Bulman (
Kirk 1969
, p. 280) disputed my basic premise of an upright
Dictyonema flabeUiforme
as the starting point of graptoloid evolution, and cited the occurrence of ‘bulb-like’ floats at the proximal end of some
D. flabelliforme
rhabdosomes, which could ‘only be interpreted as a proximal buoyancy device’ so that ‘whether suspended or floating the proximal end would be uppermost’.

In the same discussion (
Kirk 1969
, p. 283
et seq
) Rickards also challenged me on many points, among which
Metamorphic rocks from the southern end of the Rockall Bank
Authors: ROBERTS DAVID GWYN , MATTHEWS DRUMMOND HOYLE , EDEN ROBERT A.
Published: December 2007

T
wenty
one cobbles of granulite-facies metamorphic rocks of Lewisianoid aspect have been dredged from the southern end of the Rockall Bank, North Atlantic Ocean. At the same locality two large fragments of Flandrian conglomerate contain petrologically similar heavy minerals and pebbles. We argue that these rocks have a local origin and therefore confirm that Rockall Bank has a continental composition as well as a continental seismic structure.

Rockall Bank (Fig. 1) is the shoalest part of the extensive Rockall Plateau that is now known to have a continental structure from a variety of geophysical studies (a,
Roberts 1970b
;
Scrutton 1970
;
Scrutton & Roberts 1971
;
Scrutton in press
). However, geological evidence of continental granitic and metamorphic rocks has been lacking although a geochemical study of the aegirine-granite exposed on Rockall Islet suggests such rocks may underlie the Bank at depth (
Sabine 1960
;
Moorbath & Welke 1969
).

Previous geological sampling has been confined largely to the northern part of the Bank and the area immediately around Rockall Islet (
Cole 1897
; Lacroix 1921; Roberts & Wilson 1971; J. B. Wilson personal communication). These dredge hauls have yielded sparse metamorphic rocks and quantities of both basic intrusive and extrusive rocks or their derivatives that are probably coeval with the ring complex centred near the Lower Eocene granite of Rockall Islet (
Sabine 1960
;
Miller & Mohr 1965
;
Roberts 1969
). Although some of this material may be ice-rafted, magnetic anomaly interpretation (
Roberts 1969
; Roberts & Jones in
Facts and theories on the Andes
Authors: GANSSER AUGUSTO
Published: December 2007

Theories on the relation of oceanic plates with continents frequently use the Andes as a model. Simplified assumptions neglect the fact that only the recent morphogenic uplift made the apparently uniform Andes, masking a most complicated geological history.

Three main subdivisions are recognized. (I) The Southern Andes that show a virgation leading into the Scotia arc. Oceanic formations characterize the interior ranges and disappear towards the Gulf of Penas, where the Chile fracture zone joins the continent. (2) From here the Central Andes begin with a Coastal Cordillera of metamorphic, highly compressed Paleozoic and probably older rocks with an abnormal northwest strike. They are transgressed by thick, mostly volcanic Mesozoic rocks, with block fold tectonics. An intense young acid volcanism characterizes the Central ranges together with strong seismic activity that is missing in the Southern Andes. The Central Andes are bordered by the Nasca plate, which is subdivided by the aseismic Nasca ridge. The latter projects into the Andes where the metamorphic Coastal belt disappears.

(3) The Northern Andes have a marked virgation leading into the Caribbean are and display a Coastal and Western (Caribbean) Cordillera of more or less metamorphic Mesozoic oceanic rocks, in strong contrast to the Central Andes. Their southern border coincides with a major east-west lineament. This is outlined by the Carnegie–Galapagos ridge and a possible renewal of an old Amazon fracture trend aligned with the Romanche fracture zone which displaces the Mid-Atlantic ridge. The continental edge of the Cocos plate, bordering the Northern Andes, exposes oceanic sediments in marked contrast to the coastal metamorphic “basement” of the Central Andes, that borders the Nasca plate.

The Andes, being a marginal chain, are influenced by the shields to the east, which display younger remobilization along fracture zones, and by the east Pacific plates in the west. The geological complexities of the Andes, with their marked volcanism and irregular but strong seismicity, suggest that the east Pacific plates have had a much more complicated pattern than has generally been supposed.
The overturned anticline of the Northern Range of Trinidad near Port of Spain
Authors: POTTER HENRY C.
Published: December 2007

Formerly
the Northern Range of Trinidad was assumed to be the south flank of an anticline, with the north flank either out to sea or displaced by faulting. Mapping has shown that the structure is that of an anticline overturned to the north.

The steep southern limb begins with nearly vertical dips in the Chancellor formation and the Morvant beds along the Lady Young Road, and between Port of Spain and Maraval. In this upright limb are local folds 100 m to 500 m in wavelength, parallel with both the main structure and minor folds. Folds of this size have not been recognised in the overturned northern limb. West of Maraval step-like folds with alternating horizontal and vertical limbs occur on east–west axes 10 m to 100 m apart. Axial surfaces dip about 35°N, but all other minor folds in the area have axial surfaces dipping steeply southwards.

Along the axis of the main fold, which occurs in the outcrop of the Maraval limestones, dips are 40°–60°S and the flanks are isoclinal. In the whole of the over-turned northern limb dips are much flatter, commonly less than 25°, and appear to become even flatter to the north. The size of this recumbent limb suggests that it is a nappe. The underlying autochthonous beds are not seen.

A number of phases of folding are recognisable. The first folds on east-west axes were refolded on more or less parallel axes. The step-like folding west of Maraval may belong to this
The pre-Silurian rocks of Clare Island, Co. Mayo, Ireland, and the age of the metamorphism of the Dalradian Ireland
Authors: PHILLIPS W. E. ADRIAN
Published: December 2007

The Highland Boundary Fault is considered to extend from Stonehaven in Scotland to the major Leek fault of Clare Island in western Ireland. This conspicuous fault of the island has however been erroneously correlated with the Leannan fault of Donegal, a probable branch of the Great Glen Fault. South of the Leek fault Silurian sediments rest unconformably upon a metamorphic basement. This consists of amphi-bolite facies metasediments intruded by basic and ultrabasic rocks that have also undergone amphibolite facies metamorphism. These high grade rocks of uncertain age are considered to be part of a horst which was uplifted within the Moine Dalradian basin of western Ireland during Cambrian times. The horst was probably a southern source of detritus for the Upper Dalradian turbidites now on both sides of the Leek fault. The large uplift to the south which formed this horst conforms with and expands previous ideas on the early history of the Highland Boundary Fault. The age of the Dalradian metamorphism in western Ireland is reconsidered, and it is concluded that the case for a pre-
Nitidus
Zone age is unsatisfactory and that a mid-Ordovician age is possible.
A lead isotope study of Archaean mineralized areas in Tanzania
Authors: COOMER PETER G. , ROBERTSON DAVID K.
Published: December 2007

Single-stage lead extracted from pyrite and galena collected from Nyanzian greenstone belts in the northern half of the Tanzanian Shield yields a recalculated model age of 2700 ± 150 m.y. for the gold mineralization, a date that is consistent with existing radiometric ages. Anomalous multi-stage lead has also been found in the Nyanzian sulphides, and is interpreted as indicating that radiogenic lead was added to the original lead during an event 900 ± 300 m.y. ago. This event is tentatively correlated with the Bukoban phase of basic dyke intrusion.

Two mineralized areas in the adjacent Ubendian Orogenic Belt were also investigated. Lead from the Mpanda Mineral Field, also apparently single-stage, yields a model age of 1400 ±150 m.y. for the mineralization. Anomalous multi-stage leads from the Lupa Goldfield indicate that the area has experienced a complex history starting with a mineralizing event at least 2400 ±150 m.y. ago.
Facies relations in the Eocene-Oligocene in the Santa Ynez Mountains, California
Authors: VAN DE KAMP P. C. , HARPER J. D. , GONNIFF J. J. , MORRIS D. A.
Published: December 2007

Facies relationships between deep and shallow marine to continental deposits in the Eocene-Oligocene sequence of the Santa Ynez Mountains, California, have been studied in detail to (i) determine interrelationships between shallower and deeper marine sands (coastal and turbidite); (2) establish criteria for the recognition of genetic sand types; (3) determine factors influencing facies distribution; and (4) propose hypotheses of marine sand deposition. The rocks studied include the Anita, Sierra Blanca, Juncal (with the Camino Cielo Member), Matilija, Cozy Dell, and “Coldwater” formations but not the topmost unit of the Eocene-Oligocene sequence, the non-marine Sespe formation.

In landward sequence, the facies recognized include: Turbidites and marine lutites, proximal turbidites, shallow marine, coastal and continental facies. These occur in two major regressive sequences. In the first, the Juncal-Matilija sequence, thin-bedded turbidites and marine lutites are overlain by, and are laterally equivalent to, very thick proximal turbidites which pass upward into shallow marine and coastal sands. The major sand accumulations are in the basin margin shallow marine, coastal, and proximal turbidite facies. The second regression, the Cozy Dell-Sespe sequence, lacks significant proximal turbidite deposits but has extensive shallow marine and coastal deposits. Facies distribution and stratigraphical sequence are explained as responses to the interplay of depositional and structural processes.

Detailed stratigraphical mapping has clarified correlation in the Eocene sequence to the Santa Ynez Mountains. Micropaleontology is used in support of correlations and bathy-metric interpretations.
Permian of the offshore and coastal region of Durham and SE Northumberland
Authors: MAGRAW DONALD
Published: December 2007

Recent bores indicate that the basal Permian (Yellow) Sands of N Durham were deposited largely sub-aerially as dunes 50 m or more high on an almost planar Coal Measures surface. Many of these were inundated by a placid sea and covered by the Marl Slate and Passage Beds. Continued subsidence allowed the succeeding lower Magnesian Limestone to accumulate more rapidly on the slopes of thinly covered dunes possibly with relative relief of 30 m and minor slumping occurred over wide areas. Uplift and tilting led to deepening of the basin to the east and partial erosion of the lower Magnesian Limestone and Marl Slate on land followed by reef development. Anhydrite deposits formed contemporaneously or rather later than the reef. Inshore in N Durham these crystallized discretely from sulphate-rich dolomite muds possibly partly in a sabhka environment with ratio of evaporite to dolomite increasing eastwards towards the basin, ultimately to form continuous, bedded deposits some distance from the present shoreline in N Durham but on shore near Hartlepool. Breccias formed contemporaneously with the evaporites partly due to crystallization pressure and later removal of sulphate.
Cyprus umbers: basalt-sediment relationships on a Mesozoic ocean ridge
Authors: ROBERTSON A. H. F.
Published: December 2007

Overlying the upper pillow Lavas, the latest extrusives of the Troodos Massif, interpreted as Cretaceous ocean floor, there occur umbers; iron, manganese and trace-metal enriched mudstones of volcanic exhalative origin.

Umber deposits occur in hollows, underline by thin lava breccias, also by deeper zones of intensely veined and fragmented pillow lavas. Occasional thicker umber deposits are located in elongate fault-controlled depressions; within and above thick lava breccias, restricted to the south margin of the Troodos Massif; and also in depressoions inherited from earlier emplacement of stratiform cupriferous sulphides.

Umbers originated in the Campanian due to volcanism on an ocean ridge. The sub-umber veining and brecciation was produced by late-stage hydrothermal activity, associated initially, with a brief episode of violent volcanism, then with more quiescent discharge of submarine thermal springs from a geothermal system. Large volumes if dilute metalliferous brines were released into open marine waters whereupon umbers were rapidly precipitated.
Stable isotopes and geothermometry
Authors: JAVOY M.
Published: December 2007

The application of stable isotope fractionation to geothermometric problems is introduced through considerations of statistical thermodynamics first developed by H. C. Urey. The available calibrations of isotope fractionation between species of geochemical interest are reviewed. These calibrations are discussed in the light of simple theoretical considerations, and a new set of thermometric equation is derived for the most common mineral constituents of rocks. Examples of application are given for igneous and metamorphic rocks. The significance of ‘isotopic’ temperatures is discussed in terms of environmental and kinetic considerations. As an example of possible future developments we derive the relationship between observed isotope temperatures and the speed of ascent of a rock system during a postorogenic isostatic readjustment.
East African Rift System dynamics in view of Mesozoic apparent polar wander
Authors: McCONNELL R. B.
Published: December 2007

Recently published palaeomagnetic data lead to the conception that Africa has been subjected to latitudinal compression during Mesozoic seafloor spreading, and that the meridional taphrogenic lineaments of East Africa have therefore been unable to spread, although underlain by convective mantle complexes comparable to mid-ocean ridge systems. An hypothesis is outlined, based on a synthesis between geological mapping in East Africa and recent geophysical models, showing (1) how the existing taphrogenic system could have developed by the repeated thermotectonic reactivation of protorift dislocations which originated chiefly in the Precambrian, and (2) how localized tensional graben mechanisms could develop in spite of regional compressive stress.
Explosion seismology and the continental crust-mantle boundary
Authors: BAMFORD D. , PRODEHL C.
Published: December 2007

In recent years explosion seismology has produced much new knowledge about the nature of the crust-mantle boundary, and the materials that it separates in the lower crust and upper mantle. On the one hand, it is clear that both the lower crust and upper mantle contain more fine structure than was previously imagined and, on the other, that variations in deep structure correlate to some extent with surface geology. For example, a thin crust and sharp Moho are characteristic of Hercynian Europe whereas shield areas and orogenic belts are characterized by a thick crust and gradational Moho. Furthermore useful seismic constraints are now emerging regarding the materials to be found in the crust and mantle. For example, it is clear that the immediate sub-Moho material is most probably peridotite.
Cainozoic sedimentation in basins adjacent to a major continental transform boundary in southern New Zealand
Authors: Norris R. J. , Carter R. M. , Turnbull I. M.
Published: December 2007

The Indo-Australian/Pacific plate boundary crosses the New Zealand continental block as the Alpine fault system, an oblique continental transform. Plate tectonic calculations for the SW Pacific imply the inception of this plate boundary in the latest Eocene. In western South Island, rapidly subsiding flysch basins were established at this time. Southeast of the Alpine Fault, basins developed along an active tectonic trend, the Moonlight Tectonic Zone. Early Oligocene infilling by thick submarine fan sequences was accompanied by regional subsidence, so that by late Oligocene, deep marine mudstone was dominant in basins and limestone on adjacent shelf areas. In contrast, early to mid Miocene time was characterized by contemporaneous uplift and subsidence, with tectonic activity on basin margins and development of new source areas adjacent to the Alpine Fault. Reverse faulting, folding and uplift developed at about 12 Ma and continues today.

The sedimentary history is consistent with the development of the plate boundary from a zone of slow oblique extension, to a through-going continental transform, to a compressive transform system. Continental transform boundaries appear to be characterized by small, tectonically active basins, and by a complex tectonic history, particularly when close to the pole of relative rotation. Although difficult to recognise, they may be important in the geologic record.
Metallogenesis in SE Asia
Authors: Hutchison C. S. , Taylor D.
Published: December 2007

Southeast Asia may be subdivided into three distinct metallogenic provinces— (
a
) peripheral Cenozoic volcanic arc, (
b
) Mesozoic Sundaland core, and (
c
) cratonic China north of the Red River Suture:
a
is a major producer of copper with minor gold and silver;
b
is the World's foremost producer of tin with subordinate tungsten and antimony;
c
is the World's premier tungsten and antimony province, with subordinate tin and mercury.

Ophiolites, obducted since the Palaeocene from Pacific and marginal basin lithosphere, yield substantial chromite, increasing amounts of nickel from residual laterite, and massive Cyprus-type sulphides.

Palaeocene to Miocene dioritic stocks, within the ensimatic arcs of the Philippines and north Sulawesi, contain important porphyry coppers. Gold and silver are important associates, but molybdenum is rare. Kuroko-type sulphides and mesothermal copper-gold vein deposits are important in the Philippines and Taiwan. Epithermal gold-silver telluride vein deposits are more widespread throughout the Cenozoic volcanic arc.

Tin mineralization, spatially related to acid granitoids of Permo–Triassic age in Indonesia and the Malay Peninsula and of Cretaceous age in Phuket and Tenasserim, is widespread in province
b.
Important lode deposits are confined to Billiton and the East Coast Belt of the Peninsula, emplaced within the zone of fracture around high level granitoids. Some stratiform iron-tin deposits characterize this Eastern Belt. Other tin fields, which yield the bulk of the region's production, contain few worthwhile lode deposits. Huge amounts of tin have been produced from the contact zones of large deep-seated batholiths in Bangka, along the Main Range of the Malay Peninsula, and in the Phuket region of Thailand. The tin has been concentrated in Quaternary placers by the favourable combination of climate and topography.

In the Southern Shan States and north Thailand, the deposits are associated with Triassic granites and have yielded more tungsten than tin, as well as significant amounts of antimony. Major tungsten and less important tin deposits are associated with Mesozoic granitoids in the Caledonian foldbelt of southeastern China. The important antimony and mercury occurrences lie on the continental side of the tungsten-tin belt.

Gold, antimony and mercury mineralization is associated with Tertiary igneous rocks in West Borneo, and mercury occurs in Palawan island.

Iron contact-metasomatic and sedimentary ore deposits are associated with the Mesozoic igneous rocks in China and Sundaland, and with Cenozoic dioritic rocks in the Philippines.

The metallogenic zonation of China may be related to subduction of oceanic material beneath a continental margin, persistent since the early Mesozoic. In SE Asia, more complex patterns of subduction have resulted in less well defined metal zonation in the continental regions. Cenozoic mineralization in the Philippines and Indonesia resulted from convergent tectonics of great complexity involving both continental and oceanic crust of diverse origins.
The Permo-Carboniferous dyke-swarm of northern Argyll and its bearing on dextral displacement on the Great Glen Fault
Authors: Speight J. M. , Mitchell J. G.
Published: December 2007

Contour-maps of (i) percentage crustal-extension (dilation) and (ii) number of dykes per kilometre, for a regional linear WNW-trending Permo-Carboniferous dyke-swarm of northern Argyll, indicate a dextral displacement of the axis of the swarm at the Great Glen Fault by 7–8 km. The dykes are olivine-dolerites, camptonitic dolerites, camptonites and monchiquites. They are distinguished from similarly trending Tertiary dolerite dykes chiefly by their field-characters. Isotopic dates of eight dykes exhibit a range of ages, although five of these agree within the limits of experimental error, giving a mean of 285 ± 5 Ma. K-Ar ages of two Caledonian dykes are also reported. Since the Tertiary dyke-swarm of Skye is not laterally displaced at the Great Glen Fault, the dextral slip dates from between the dyke-swarms. Comparatively lower intensities of both Permo-Carboniferous and Tertiary dykes south of the fault suggest considerable downthrow to the southeast. At least part of the normal faulting is of post- or syn-Tertiary dyke-swarm date, though the Great Glen Fault may, in addition, have acted as a barrier to the southerly continuation of the Skye dyke-swarm.
Side-scan sonar studies of North Atlantic fracture zones
Authors: Searle R. C.
Published: December 2007

The Institute of Oceanographic Sciences has studied zones in 3 locations along the N mid-Atlantic Ridge and one on the Azores-Gibraltar plate boundary. 2 areas have short (~20 km) offsets and the others large ones (> 100 km). An important new observation is that probably all of these fracture zones are associated with
en echelon
, 20 km long scarps striking about 45
°
to the fracture zone. These scarps are believed to develop from oblique faults formed in the early stages of shearing. In addition, true transform faults associated with long, linear valleys occur in the large-offset fractures. Their appearance is similar to that of large continental strike-slip faults. The observed morphology and tectonics of the fracture-zone valleys generally accords with the description of Francheteau
et al
. (1976). The small-offset fracture zones have asymmetric cross sections which are attributed to the interplay of median valley and fracture-zone tectonics. Only one case of a possible intrusive ridge has been tentatively identified, in the inactive portion of Charlie-Gibbs Fracture Zone. An improved instantaneous rotation pole for Africa/Eurasia has been determined from the trace of the Gloria Fault on the Azores-Gibraltar plate boundary.
Objectives of volcanic monitoring and prediction
Authors: Fournier d'Albe E. M.
Published: December 2007

Effective volcanic-risk management requires that prediction should cover time intervals comparable with the time-scale of human and social responses to them. Two main responses are: appropriate land-use and location of settlements (time-scale: decades); and emergency evacuation of danger zones (time-scale: days or hours). The first response may be optimized through volcanic zoning and risk assessment, based on the precise mapping and dating of previous events. The second demands the close cooperation or integration of scientists and civil defence in order (
a
) to define levels of risk and the corresponding social responses,
(b)
to define the time-scale and required accuracy of useful predictions, and
(c)
to devise appropriate monitoring systems.
Rubidium-strontium whole-rock isochron evidence for the age of metamorphism and magmatism in the Mona Complex of Anglesey
Authors: Beckinsale R. D. , Thorpe R. S.
Published: December 2007

The Mona Complex comprises a 'Bedded Succession' of late Proterozoic low-grade metasedimentary schists, a group of gneisses of uncertain age, and the Coedana Granite. New Rb-Sr whole-rock isochron data for gneisses from the Holland Arms area indicate a late Precambrian metamorphic episode at 595 ± 12 Ma and a possible Cambrian igneous episode represented by an age with relatively large errors of 562 ± 31 Ma obtained from orthogneisses. A Rb-Sr whole-rock isochron age for the Coedana granite is 603 ± 34 Ma. The relatively low initial
87
Sr/
86
Sr ratio for the late Precambrian gneisses, 0.7061 ± 3, is considered to preclude a long crustal history for these rocks and they are identified as metamorphosed equivalents of part of the Bedded Succession. The initial
87
Sr/
86
Sr ratios of the orthogneisses and the Coedana Granite (0.7081 ± 8 and 0.7086 ± 9, respectively) are identical within analytical error and are consistent with an origin for these igneous rocks either by crustal contamination of mantle-derived melts, or by melting of young crustal material such as the older gneisses.
The nature, ascent and emplacement of granitic magmas
Authors: Pitcher W.S.
Published: December 2007

The address is a wide-ranging commentary on the physical aspects of granitic magma and deals especially with the mode of emplacement. Recommendations on the nomenclature of plutons and batholiths involve both a description of the actual shape and their modeling by experimental and salt-diapir analogues. The nature of granitic crystal-mushes, wet or dry, is discussed in the light of the special properties of pseudoplastics, particularly the influence of the physical state on the sinking of crystals and xenoliths, on magma mobility in zoned plutons, and on the final rock structure. The longevity of plutonic events and their episodic character are commented on in relation to the subduction process. The generation of granitic magmas, their upwelling and the structural control of their intrusion, whether forceful or permissive, are discussed. The structural form of batholiths in depth is described in terms of a batholith denudation series particularly in the circum-Pacific context. Finally, two main orogenic environments of granites are contrasted in terms of the Hercynotype and Andinotype, and composition and structure are interrelated in a proposed general model for the emplacement of batholiths.
New light on the Moine rocks of the Central Highlands of Scotland
Authors: Piasecki M. A. J.
Published: December 2007

On the basis of new evidence, the Moine rocks SE of the Great Glen Fault are differentiated into two major units: the Central Highland Division, represented by a gneissose assemblage of about 1000 km
2
extent, and the Grampian Division, a younger and more extensive sequence of less deformed metasediments which is separated from the gneisses by a tectonic break, the Grampian Slide. Since the 2 Divisions have greatly differing tectonometamorphic histories, they are believed to correspond respectively to a basement complex and a cover sequence. The discovery of a suite of syntectonic Precambrian pegmatites (
c
. 718 ± 19 Ma) equivalent in age to the Morarian pegmatites of Morar and Knoydart, permits the separation of Precambrian from Caledonian orogenic events.

The Central Highland division is considered to be an eastward extension of the high-grade rocks which in part form the Glenfinnan Division W of the Great Glen Fault, widely held to be of Grenvillian age, whilst the Grampian Division is interpreted as early post-Grenvillian sediments affected first by a limited Morarian orogenic event, and subsequently by the Caledonian orogeny.
The sub-ophiolite metamorphic rocks of the Ballantrae Igneous Complex, SW Scotland
Authors: Spray J. G. , Williams G. D.
Published: December 2007

A schistose metamorphic 'aureole' adjacent to serpentinite is described from 3 localities (Carleton Hill, Knocklaugh farm and Loch Lochton) between the Northern Serpentinite and the Knockormal-Knocklaugh spilites of the Ballantrae Igneous Complex, SW Scotland. Whole-rock and electron microprobe analyses confirm that this c. 40 m thick metamorphic sole essentially comprises a metabasite sequence and that it progrades towards the serpentinite from greenschist to amphibolite-granulite facies. 4 phases of pre-Caradocian deformation are recognized. It is suggested that the sole was formed mainly by tectonic displacement of hot ultramafics against basic rocks. It is likely that this metamorphism developed due to thrusting occurring in a major fault zone initiated within oceanic lithosphere.
Possible Palaeozoic drift of SE Asia and Triassic collision with China
Authors: Ridd M. F.
Published: December 2007

The Palaeozoic and early Mesozoic rocks of the Thai–Malay Peninsula provide evidence of having had a subduction zone to the E and, in the Lower Palaeozoic, a cratonic sediment source to the W. Earlier attempts to explain that palaeogeography in plate tectonic terms involved or implied a northward drift from Gondwanaland and collision with mainland Asia in the Tertiary. That timing of events is unsatisfactory in several respects. Instead it is suggested that separation from Gondwanaland took place in mid-Palaeozoic times and that collision took place in the late Triassic. This fits closely the model put forward by Sengör for the western part of the Tethyan belt.
Geochemical evolution in an advancing, periodically replenished, periodically tapped, continuously fractionated magma chamber
Authors: O’Hara M. J. , Mathews R. E.
Published: December 2007

A summary of the development of ideas concerning geochemical evolution in periodically replenished, periodically tapped, continuously fractionated magma chambers lists 28 main conclusions or observations. The main body of the paper presents the derivations of the relationships which underpin these conclusions and lead on to a further 10 observations about the likely behaviour of such systems.

If periodically replenished, periodically tapped, continuously fractionated magma chambers exist, they will evolve products whose phase petrology and trace element chemistry appear (in hitherto conventional interpretations) to require variable degrees of partial melting of in homogeneous source regions for their petrogenesis. When the additional effects arising from assimilation by the magma of the roof of the chamber and from variation of mineralogy at the solidus of even a chemically homogeneous peridotite mantle are added, the scope for confusion is greatly increased. Moreover, these relationships cannot be inverted in order to deduce uniquely the magma chamber parameters or mantle source compositions from a knowledge of the erupted products. Available evidence suggests that interpretation of many igneous provinces, especially that of the mid-ocean ridges, will be complicated by these considerations.
The geology of the Kuh-e Dalneshin area of southern Iran, and its bearing on the evolution of southern Tethys
Authors: Stoneley R.
Published: December 2007

The Kuh-e Dalneshin area lay close to the northern margin of the Arabian continent during Mesozoic and Palaeogene times. Recent mapping has shown that, except perhaps in the late Cretaceous, it was inactive until it collided with Central Iran in the Miocene: the collision, represented by a Neogene mélange zone in the NE, resulted in the Zagros orogeny, and is expressed in the shelf sediments by folding, parallel faulting and a possible arcuate sinistral shear.

In the late Cretaceous, a localized deepening of the shelf dates from the Cenomanian. A narrow trough in the W subsided to abyssal depths in the Turonian. Following a period of faulting, a more wide spread subsidence affected the shelf in the Coniacian and Santonian: autochthonous cherts and associated sediments accumulated. Basaltic volcanics were erupted in the NE part of this basin, and Permian to Cenomanian neritic exotic blocks were derived presumably from an uplift at the shelf edge. The rocks from the outer edge of this basin slid westwards over their autochthonous counterparts, probably in the Campanian, accompanied by further gliding of masses of earlier Mesozoic cherts, which had previously been emplaced on the continental margin. A sheet of mantle peridotite, partly serpentinized and enclosing neritic and metamorphic exotics, in turn slid into the basin. Shelf sedimentation was renewed in the late Campanian or Maestrichtian, but the transgression did not reach the area until the Eocene.

The derivation and emplacement of the allochthonous rocks in the late Cretaceous are still imperfectly understood: alternative models are discussed, one involving gliding from an aborted spreading ridge along the continental margin, the other more conventionally based on subduction processes. A preference is expressed for the former.
Seismic refraction evidence for a basement ridge between the Derbyshire Dome and the W of Charnwood Forest
Authors: Whitcombe D. N. , Maguire P. K. H.
Published: December 2007

Results from a 40-km seismic refraction profile crossing a series of positive gravity anomalies extending across the postulated mouth of the Widmerpool Gulf are reported. A refractor with a similar velocity to the Precambrian rocks of Charnwood Forest dips away from Charnwood to the southern flank of the Derbyshire Dome to a depth of 2 km. This refractor is faulted into horst and graben structures. The horst blocks correlate with the positive gravity anomalies. A northern boundary fault to the Precambrian outcrops of Charnwood is defined.
The genesis of the Gaborone rapakivi granite complex in southern Africa
Authors: Key R. M. , Wright E. P.
Published: December 2007

The Gaborone Granite is a mushroom-shaped intrusion with a surface area of over 5000 km
2
. The intrusion is layered, consisting of a central core of rapakivi granite (Thamaga Granite) surrounded by successive shells of an equigranular leucocratic granite (Kgale Granite), a porphyritic granophyre or microgranite (Ntlhantlhe Microgranite) and an outermost zone of massive felsite (Kanye Volcanics). The whole lithological sequence is deduced to have been derived from a single, highly viscous magma body emplaced into the crust at a high level. The genesis is proposed as follows.

The outer felsites represent quenched primary magma with the underlying porphyritic granophyres having formed during a subsequent tranquil period after emplacement. The rapakivi granite core was also of early crystallization above the floor but with significant textural characters impressed during updoming in the late crystallization stage. Residual liquid rich in SiO
2
, K
2
O and volatiles migrated upwards to form the Kgale Granite.

The Gaborone Granite was emplaced in the Kaapvaal Craton at about 2400 Ma and its morphology was controlled by pre-existing structures in the crust. The country rock consists of Archaean gneisses, Lobatse Volcanic Group supracrustals and locally Transvaal Supergroup strata. Chemically the Gaborone Granite is identical to other early Proterozoic non-orogenic granites of the Kaapvaal Craton. It is also similar in many respects to the Fennoscandian rapakivi granites