Application of a seismograph network and electronic computer in near earthquake studies

1962 ◽  
Vol 52 (3) ◽  
pp. 673-682
Author(s):  
J. Cleary ◽  
H. Doyle
Keyword(s):  
Upper Mantle ◽  
Main Shock ◽  
Electronic Computer ◽  
Surface Velocity ◽  
Origin Time ◽  
Southeastern Australia ◽  
Interesting Pattern ◽  
Eastern Australia ◽  
Seismograph Network ◽  
Velocity Decrease

Abstract A description is given of the application of a close network of seismograph stations and of an IBM 650 computer program to the study of a sequence of near earthquakes in southeastern Australia. The epicenters, depths, and origin times of a moderate sized earthquake and its aftershocks were determined with unusual accuracy, revealing an interesting pattern of foci. The position and origin time of the main shock were then used to study arrivals at more distant stations; Pn arrivals were found to fit a linear travel-time equation closely to a distance of 15 degrees, with a surface velocity of 8.16 ± 0.03 km/sec. The Sn phase was not clear and gave an approximate velocity of 4.7 ± 0.2 km/sec. The possibility of a small velocity decrease in the upper mantle below eastern Australia is discussed.

Moment-tensor solutions for the 24 November 1987 Superstition Hills, California, earthquakes

1989 ◽  
Vol 79 (2) ◽  
pp. 493-499
Author(s):  
Stuart A. Sipkin
Keyword(s):  
Main Shock ◽  
Moment Tensor ◽  
Time Dependent ◽  
Origin Time ◽  
Data Set ◽  
Filter Theory ◽  
Long Period ◽  
Seismograph Network ◽  
Scalar Moment

Abstract The teleseismic long-period waveforms recorded by the Global Digital Seismograph Network from the two largest Superstition Hills earthquakes are inverted using an algorithm based on optimal filter theory. These solutions differ slightly from those published in the Preliminary Determination of Epicenters Monthly Listing because a somewhat different, improved data set was used in the inversions and a time-dependent moment-tensor algorithm was used to investigate the complexity of the main shock. The foreshock (origin time 01:54:14.5, mb 5.7, Ms 6.2) had a scalar moment of 2.3 × 1025 dyne-cm, a depth of 8 km, and a mechanism of strike 217°, dip 79°, rake 4°. The main shock (origin time 13:15:56.4, mb 6.0, Ms 6.6) was a complex event, consisting of at least two subevents, with a combined scalar moment of 1.0 × 1026 dyne-cm, a depth of 10 km, and a mechanism of strike 303°, dip 89°, rake −180°.

scholarly journals Towards community-driven paleogeographic reconstructions: integrating open-access paleogeographic and paleobiology data with plate tectonics

2013 ◽  
Vol 10 (3) ◽  
pp. 1529-1541 ◽  
Author(s):  
N. Wright ◽  
S. Zahirovic ◽  
R. D. Müller ◽  
M. Seton
Keyword(s):  
Ocean Circulation ◽  
Plate Tectonics ◽  
Numerical Models ◽  
Plate Motion ◽  
Temporal Data Mining ◽  
Dynamic Topography ◽  
Southeastern Australia ◽  
Eastern Australia ◽  
Spatio Temporal ◽  
Fossil Data

Abstract. A variety of paleogeographic reconstructions have been published, with applications ranging from paleoclimate, ocean circulation and faunal radiation models to resource exploration; yet their uncertainties remain difficult to assess as they are generally presented as low-resolution static maps. We present a methodology for ground-truthing the digital Palaeogeographic Atlas of Australia by linking the GPlates plate reconstruction tool to the global Paleobiology Database and a Phanerozoic plate motion model. We develop a spatio-temporal data mining workflow to validate the Phanerozoic Palaeogeographic Atlas of Australia with paleoenvironments derived from fossil data. While there is general agreement between fossil data and the paleogeographic model, the methodology highlights key inconsistencies. The Early Devonian paleogeographic model of southeastern Australia insufficiently describes the Emsian inundation that may be refined using biofacies distributions. Additionally, the paleogeographic model and fossil data can be used to strengthen numerical models, such as the dynamic topography and the associated inundation of eastern Australia during the Cretaceous. Although paleobiology data provide constraints only for paleoenvironments with high preservation potential of organisms, our approach enables the use of additional proxy data to generate improved paleogeographic reconstructions.

Preliminary report on some aftershocks of the December 28, 1966 earthquake in Northern Chile

1968 ◽  
Vol 58 (3) ◽  
pp. 843-850 ◽  
Author(s):  
Andrew M. Pitt ◽  
James O. Ellis
Keyword(s):  
Upper Mantle ◽  
Lower Crust ◽  
Preliminary Report ◽  
Main Shock ◽  
Geodetic Survey ◽  
Northern Chile ◽  
The U.S

abstract Epicenters of aftershocks of the December 28, 1966 earthquake in northern Chile lie in a 75-km north-trending zone 20 to 30 km off the coastline. The epicenter for the main shock, as determined by the U.S. Coast and Geodetic Survey, is about 10 km north of the southern end of the aftershock zone. The aftershocks are about 30 km deep in the model used for locations; this places them in the lower crust or upper mantle. The aftershocks have no apparent relation to any surface faults.

Dispersal of Irradiated Queensland Fruit-Flies, Dacus-Tryoni (Froggatt) (Diptera, Tephritidae), in Southeastern Australia

1987 ◽  
Vol 35 (3) ◽  
pp. 275 ◽  
Author(s):  
JR Macfarlane ◽  
RW East ◽  
RAI Drew ◽  
GA Betlinski
Keyword(s):  
Fruit Flies ◽  
Long Distance ◽  
South Eastern ◽  
Southeastern Australia ◽  
Mark Release Recapture ◽  
Eastern Australia ◽  
South Eastern Australia

Mark-release-recapture studies with laboratory-reared irradiated Dacus tryoni (Froggatt) were undertaken in summer in south-eastern Australia. These showed that flies can disperse up to 94 km, almost four times the furthest distance recorded previously for this species. Most recaptures beyond 6 km were east of the point of release. Several distant traps each caught more than one fly, indicating that the flies moved together over long distances. This suggests that mating could occur and that new infestations could result from the long-distance migration of adults.

scholarly journals The structure of the lithosphere and upper mantle beneath the Eastern Mediterranean and Middle East

2020 ◽  
Vol 2 (3) ◽  
pp. 311-326 ◽  
Author(s):  
Dan McKenzie
Keyword(s):  
Middle East ◽  
Shear Wave ◽  
Upper Mantle ◽  
Eastern Mediterranean ◽  
Three Dimensional ◽  
Surface Velocity ◽  
Wave Velocities ◽  
Shear Wave Velocities ◽  
Surface Measurements ◽  
Lithosphere Thickness

AbstractSurface velocity measurements show that the Middle East is one of the most actively deforming regions of the continents. The structure of the underlying lithosphere and convecting upper mantle can be explored by combining three types of measurement. The gravity field from satellite and surface measurements is supported by the elastic properties of the lithosphere and by the underlying mantle convection. Three dimensional shear wave velocities can be determined by tomographic inversion of surface wave velocities. The shear wave velocities of the mantle are principally controlled by temperature, rather than by composition. The mantle composition can be obtained from that of young magmas. Application of these three types of observation to the Eastern Mediterranean and Middle East shows that the lithosphere thickness in most parts is no more than 50-70 km, and that the elastic thickness is less than 5 km. Because the lithosphere is so thin and weak the pattern of the underlying convection is clearly visible in the topography and gravity, as well as controlling the volcanism. The convection pattern takes the form of spokes: lines of hot upwelling mantle, joining hubs where the upwelling is three dimensional. It is the same as that seen in high Rayleigh number laboratory and numerical experiments. The lithospheric thicknesses beneath the seafloor to the SW of the Hellenic Arc and beneath the NE part of the Arabian Shield are more than 150 km and the elastic thicknesses are 30–40 km.

Phylogeny and biogeography of the Australasian centipede Henicops (Chilopoda: Lithobiomorpha): A combined morphological and molecular approach

2006 ◽  
Vol 37 (3) ◽  
pp. 241-256 ◽  
Author(s):  
Donald Colgan ◽  
Gregory Edgecombe ◽  
Deirdre Sharkey
Keyword(s):  
New Zealand ◽  
Western Australia ◽  
New Caledonia ◽  
Sequence Data ◽  
Morphological Characters ◽  
Molecular Data ◽  
28S Rrna ◽  
Southeastern Australia ◽  
Lord Howe Island ◽  
Eastern Australia

AbstractThe lithobiomorph centipede Henicops is widely distributed in Australia and New Zealand, with five described species, as well as two species in New Caledonia and Lord Howe Island. Parsimony, maximum likelihood and Bayesian analyses of ca. 800 aligned bases of sequence data from 16S rRNA and 28S rRNA were conducted on a dataset including multiple individuals of Henicops species from populations sampled from different parts of species' geographic ranges, together with the allied henicopines Lamyctes and Easonobius. Morphological characters are included in parsimony analyses. Molecular and combined datasets unite species from eastern Australia and New Zealand to the exclusion of species from Western Australia, New Caledonia and Lord Howe Island. The molecular data favour these two geographic groupings as clades, whereas inclusion of morphology resolves New Caledonia, Lord Howe Island, southwest Western Australia and Queensland as successive sisters to southeastern Australia and New Zealand. The basal position of the Lord Howe Island species in the phylogeny favours a diversification of Australasian Henicops since the late Miocene unless the Lord Howe species originated in a biota that pre-dates the island. The molecular and combined data resolve the widespread morphospecies H. maculatus as paraphyletic, with its populations contributing to the geographic groupings New South Wales + New Zealand and Tasmania + Victoria.

Kimberlite and kimberlitic intrusives of southeastern Australia

1980 ◽  
Vol 43 (330) ◽  
pp. 727-731 ◽  
Author(s):  
John Ferguson
Keyword(s):  
Partial Melting ◽  
Late Jurassic ◽  
Incompatible Element ◽  
Spatial Association ◽  
South Eastern ◽  
Southeastern Australia ◽  
Eastern Australia ◽  
Kimberlite Magma ◽  
Element Contents

SummaryFifteen widely separated occurrences of kimberlite and kimberlitic rocks are now known in south-eastern Australia. Those that have been satisfactorily dated isotopically give ages ranging from Permian to Late Jurassic. One occurrence exhibits an intimate spatial association with carbonatite. The classification of these rocks as ‘kimberlitic’ is partly based on their mode of emplacement, and particularly on the presence of crust/mantle inclusions. Compared with African kimberlitic magmas, the southeastern Australian examples have lower incompatible-element contents. These differences are interpreted as representing slightly greater degrees of partial melting of a four-phase Iherzolite assemblage at shallower depths (∼ 65 km) than typical African kimberlite magma.

Description of capillariid nematodes (Trichinelloidea: Capillariidae) parasitic in Australian marsupials and rodents

Zootaxa ◽  
2006 ◽  
Vol 1348 (1) ◽  
pp. 1 ◽  
Author(s):  
DAVID M. SPRATT
Keyword(s):  
Molecular Evidence ◽  
Epithelial Tissue ◽  
Additional Species ◽  
New Host ◽  
Diverse Range ◽  
Nasal Sinus ◽  
Southeastern Australia ◽  
Eastern Australia ◽  
The Family ◽  
Murid Rodents

Capillariid nematodes (Trichinelloidea: Capillariidae) parasitic in Australian dasyurid, peramelid and potoroid marsupials and murid rodents are described. Diagnosis of the genus Eucoleus and a key to species are given. Two species are redescribed: E. gastricus (Baylis) and E. rickardi (Beveridge and Barker), comb. nov. Nine species are described as new: E. breviductus sp. nov., E. buckenbourensis sp. nov., E. fluvidus sp. nov., E. longiductus sp. nov., E. parvulus sp. nov., E. perplexus sp. nov., E. plumosus sp. nov., E. posterus sp. nov. and E. pseudoplumosus sp. nov. Three additional species are recognized but not named. Species of Eucoleus occur in a diverse range of epithelial tissue habitats in Australian hosts throughout eastern Australia; one species is known from peramelids in Western Australia. Members of the genus have not been found in any other families of Australian marsupials. Three species are parasites of dasyurids, eight species are parasites of peramelids, two species occur in both dasyurid and peramelid hosts and two species are parasites of murid rodents. Morphologically, species of Eucoleus appear to be reasonably host specific at the family level. Molecular evidence indicates that sibling species of Eucoleus occur in distinct but closely related host species. Baruscapillaria conspecta sp. nov. is described from murid rodents and the potoroid marsupial rufous rat kangaroo, Aepyprymnus rufescens, primarily in north Queensland. Capillaria ornamentata sp. nov. is described from the distal nasal sinus behind the orbit of the eye of species of dasyurids of the genus Antechinus in southeastern Australia. Aonchotheca praeputialis (Obendorf, 1979) comb. nov. is redescribed and appears to occur exclusively in the native Rattus fuscipes. New host and geographic records, and tissue localities of the trichurid nematode, Anatrichosoma haycocki (Trichinelloidea: Trichuridae, Trichosomoidinae) are given.

The occurrence of the yellow-footed antechinus Antechinus flavipes in remnant linear habitats in north-eastern Victoria.

2003 ◽  
Vol 25 (1) ◽  
pp. 97 ◽  
Author(s):  
der Ree R van
Keyword(s):  
Agricultural Landscape ◽  
South Australia ◽  
Southeastern Australia ◽  
Linear Habitats ◽  
South Wales ◽  
Eastern Australia ◽  
Temperate Woodlands ◽  
North Eastern ◽  
Antechinus Stuartii ◽  
Antechinus Agilis

THE yellow-footed Antechinus Antechinus flavipes is distributed from South Australia, through central Victoria, New South Wales and into Queensland as well as in south-western Australia (Van Dyck 1998). In south-eastern Australia, the conservation of A. flavipes is not assured because its range largely corresponds with the temperate woodlands that have undergone extensive clearing and degradation (Menkhorst 1995). Despite this, no studies on the effects of the loss and fragmentation of habitat on A. flavipes have been published in the scientific literature. In contrast, numerous ecological studies that investigate the consequences of anthropogenic disturbance have been undertaken on its congeners, the brown antechinus Antechinus stuartii and agile antechinus Antechinus agilis (e.g., Bennett 1987; Downes et al. 1997; Knight and Fox 2000). These studies indicate that the abundance of these species may be influenced by patch size (Bennett 1987; Dunstan and Fox 1996), distance to large forest blocks (Downes et al. 1997), habitat structure (Knight and Fox 2000) and degree of tolerance to modified habitats that surround the patch (Knight and Fox 2000). Can the response of A. stuartii and A. agilis be used to predict how the loss, fragmentation and degradation of habitat may affect A. flavipes? In this note, I provide preliminary information about a population of A. flavipes occupying linear fragments of woodland in an agricultural landscape in southeastern Australia.

Lower Permian Brachiopods from Wasp Head Formation, Sydney Basin, Southeastern Australia

2014 ◽  
Vol 88 (3) ◽  
pp. 531-544 ◽  
Author(s):  
Gabriela A. Cisterna ◽  
G. R. Shi
Keyword(s):  
Sedimentary Facies ◽  
Lower Permian ◽  
Marine Fauna ◽  
Southeastern Australia ◽  
Eastern Australia ◽  
Head Formation ◽  
Low Diversity ◽  
Characteristic Species ◽  
Brachiopod Fauna ◽  
First Time

Although there is a generally accepted framework for the Permian marine biogeography of Australia, significant uncertainties remain concerning the temporal biogeographical changes closely related to the timing of Permian glacial–interglacial events. Several recent studies along these research lines demonstrate the importance of a reliable high-resolution biostratigraphical timescale for paleobiogeographical and paleoclimatic reconstructions. This paper provides, for the first time, a full taxonomic and biostratigraphical study of the brachiopod fauna from the Wasp Head Formation, southern Sydney Basin, southeastern Australia. The fauna is associated with deposits of the first Permian glacial interval suggested for eastern Australia. Three brachiopod assemblages are recognized. The lower and middle assemblages contain scarce brachiopods although associated bivalves are comparatively more common. Despite very low diversity and low abundance, these two brachiopod assemblages contain characteristic species of the Strophalosia concentrica and Strophalosia subcircularis brachiopod zones, both considered of late Asselian age. The third assemblage, occurring in the uppermost part of the formation, contains more brachiopods than bivalves and is referred to early Sakmarian in age. The species diversity and stratigraphic occurrences of the brachiopod assemblages in relation to sedimentary facies suggest that the lower two assemblages may represent an intra-glacial interval while the younger third assemblage, characterized by abundant occurrences of Trigonotreta and Tomiopsis species, accompanied by the bivalve Eurydesma, is more indicative of a post-glacial benthic marine fauna comparable to coeval brachiopod faunas found elsewhere in Gondwana.

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