Microearthquake surveys in the Central and Northern Philippines

abstract Microearthquake surveys were carried out in three sections of Central and Northern Philippines during 1975-1976 for a period of 5 months. A 4-month survey of Bataan Peninsula identified a major tectonic feature near Manila Bay which could not have been postulated from examination of seismicity maps. This feature appears to be situated near the southern end of ultramafic rocks of West Central Luzon and West Luzon Trough and trends W-SW from east of Corregidor Island toward Manila Trench for a distance of about 100 km. This survey also showed no microearthquake activity beneath two presently inactive volcanoes on Bataan Peninsula. The rate of activity in Bataan Peninsula region was found to be very low (8.4 events/1000 km2/yr). A short-duration survey (16 days) of the Philippine Fault in North Central Luzon revealed no microearthquake activity on the fault. During a third short-duration survey (16 days), the Verde Island Passage area between Luzon and Mindoro was found to be as highly active at the microearthquake level as it is for large earthquakes.

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Geochemical comparison of mafic, felsic, and ultramafic rocks in the Hurricane Mountain mélange to the Boil Mountain ophiolite complex, west-central Maine

Atlantic Geology ◽

10.4138/1969 ◽

2001 ◽

Vol 37 (1) ◽

Author(s):

Harriet E. Van Vleck ◽

Rachel J. Beane

Keyword(s):

Ultramafic Rocks ◽

Ophiolite Complex ◽

West Central

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Prevalence of malaria among HIV patients on highly active antiretroviral therapy in Kogi State, North Central Nigeria

Annals of Nigerian Medicine ◽

10.4103/0331-3131.189802 ◽

2016 ◽

Vol 10 (1) ◽

pp. 11 ◽

Cited By ~ 2

Author(s):

FrederickOlusegun Akinbo ◽

PeterJoel Anate ◽

DavidBolaji Akinbo ◽

Richard Omoregie ◽

Stephen Okoosi ◽

...

Keyword(s):

Antiretroviral Therapy ◽

Highly Active Antiretroviral Therapy ◽

Hiv Patients ◽

North Central ◽

Highly Active

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New Survey of Archaeological Research and Dates for West-Central and North-Central Africa

The Journal of African History ◽

10.1017/s0021853700020223 ◽

1982 ◽

Vol 23 (1) ◽

pp. 1-15 ◽

Cited By ~ 24

Author(s):

Pierre De Maret

Keyword(s):

Present Article ◽

Central Africa ◽

Archaeological Research ◽

North Central ◽

West Central ◽

Politique Économique

Le présent article fait la synthèse pour l'Afrique centrale des recherches archéo-logiques, et plus particulièrement des datations absolues, effectuées ces quatre dernières années. Comme les autres articles de cette série, seuls sont pris en considération les travaux se rapportant à la fin de l'âge de la pierre et à l'âge du fer. Eu égard à l'immensité de l'aire envisagée, l'archéologie apparaît, en dehors de quelques zones limitées, comme encore fort peu développée. Certains résultats récents méritent cependant d'être notés.Au Cameroun on dispose maintenant de dates qui permettent pour la première fois de situer les débuts de la production de nourriture ainsi que l'apparition de la céramique dans la frange nord de la forêt équatoriale. Plus au sud, à Kinshasa, il a finalement été possible de dater l'âge du fer ancien. Vers l'est, au Rwanda, de nouvelles dates pourraient confirmer que l'âge du fer a débuté dans la région interlacustre un ou deux siècles plus tôt que ce que l'on admet généralement. Dans ce pays et au Burundi l'étude systématique des anciens fourneaux de fonte du fer a été poursuivie. L'apparition des vestiges caractérisant la seconde période de l'âge du fer doit également être reculée dans le temps. Au sud-est, à Lubumbashi, une date conduit à vieillir encore le début de la fonte du cuivre. Dans la dépression de l'Upemba la fouille de plusieurs sites et de nombreuses nouvelles datations permettent de suivre avec précision pendant près de deux millénaires l'évolution sociale, politique, économique et technique de cette important zone de peuplement. Un éclairage nouveau est ainsi porté sur l'origine de l'Etat luba. Différentes recherches en rapport avec les traditions orales et l'histoire récente ont aussi été effectuées au centre du Zaïre, en Angola, au Cameroun au Rwanda et au Tchad.

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Conodont biostratigraphy and depositional history of strata comprising the Niagaran sequence (Silurian) in the northern part of the Cincinnati Arch region, west-central Ohio, and evolution of Kockelella walliseri (Helfrich)

Journal of Paleontology ◽

10.1017/s002233600002566x ◽

1994 ◽

Vol 68 (1) ◽

pp. 141-153 ◽

Cited By ~ 7

Author(s):

Mark A. Kleffner

Keyword(s):

Evolutionary Trends ◽

Depositional History ◽

North Central ◽

Lateral Process ◽

Eastern Flank ◽

West Central ◽

Basal Cavity ◽

History Of ◽

Main Lineage ◽

Greene County

The Dayton, Osgood, and Laurel Formations and the Euphemia, Springfield, and basal part of the Cedarville Dolomites near the axis of the Cincinnati Arch in northeast Preble County, Ohio, belong in the uppermost part of the Ozarkodina sagitta rhenana to lower part of the Ozarkodina? crassa Chronozone and are late early to middle Wenlockian in age. The Dayton–Cedarville succession on the eastern flank of the Cincinnati Arch in north-central Greene County, Ohio, belongs in the uppermost part of the Pterospathodus celloni to upper part of the Ancoradella ploeckensis Chronozone and is late Llandoverian to early middle Ludlovian in age.The sea transgressed across the exposed and eroded Brassfield Formation to begin deposition of the Dayton Formation on the eastern flank of the Cincinnati Arch in Greene County, Ohio, during the late Llandoverian and completely flooded all of west-central Ohio by the late early Wenlockian. The region remained covered by a sea of fluctuating depth during deposition of the Dayton Formation–Cedarville Dolomite succession from the Wenlockian through early middle Ludlovian.Kockelella walliseri (Helfrich) evolved from K. ranuliformis (Walliser) during the middle Wenlockian (upper part of Ozarkodina sagitta rhenana Chronozone) by development of a lateral process adjacent to the cusp on the Pa element and by minor modification of the Pb element and some of the ramiform elements. Specimens from upper Llandoverian and lower Wenlockian strata previously assigned to K. walliseri belong to a different species, Kockelella sp. A Fordham, 1991. The evolutionary trends in the K. walliseri lineage, progressive restriction of the basal cavity and increasing development of the length of the lateral processes in the Pa element, parallel the trends in the K. amsdeni–K. stauros–K. variabilis lineage and resulted in the divergence of Kockelella cf. K. stauros Bischoff, 1986, from the main lineage in the middle Wenlockian.

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Petrology and geochemistry of selected talc-bearing ultramafic rocks and adjacent country rocks in north-central Vermont

Professional Paper ◽

10.3133/pp345 ◽

1962 ◽

Cited By ~ 13

Author(s):

A.H. Chidester

Keyword(s):

Ultramafic Rocks ◽

North Central ◽

Adjacent Country ◽

Petrology And Geochemistry

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Geographic variation in quantitative skull traits and systematic of southern populations of the leaf-eared mice of the Phyllotis xanthopygus complex (Cricetidae, Phyllotini) in southern South America

Zootaxa ◽

10.11646/zootaxa.4446.1.5 ◽

2018 ◽

Vol 4446 (1) ◽

pp. 68

Author(s):

PABLO TETA ◽

J. PABLO JAYAT ◽

CECILIA LANZONE ◽

AGUSTINA OJEDA

Keyword(s):

South America ◽

Molecular Data ◽

Valid Species ◽

Skull Morphology ◽

North Central ◽

Southern South America ◽

Central Argentina ◽

The North ◽

West Central ◽

Neotropical Rodents

The leaf-eared mice of the genus Phyllotis (Cricetidae, Phyllotini) encompasses at least 20 species of medium-sized Neotropical rodents mostly distributed throughout the Andean region. Its limits and contents were reviewed by several authors, based both on morphological and molecular data. However, no integrative approaches were conducted based on large samples of individuals with a wide geographical coverage. The purposes of this paper are: (i) to evaluate species limits; and (ii) to test the congruence between molecular and quantitative morphological evidences within the Phyllotis xanthopygus complex in southern South America. Our results questioned the specific status of P. bonariensis, a geographically isolated form that was either considered as a valid species or as a synonym of P. xanthopygus. Quantitative morphological (size and shape of the skull) and molecular data linked P. bonariensis with populations from central Argentina traditionally referred as P. xanthopygus vaccarum. Individuals belonging to populations from southern Argentina and Chile (P. x. xanthopygus) were remarkably homogeneous in their skull morphology, showing a subtle to non-existent differentiation from those of north-central and west-central Argentina referred to P. x. vaccarum. We found some incongruence between groups inferred from morphological (this work) and mitochondrial DNA results of previous studies. This is the case of the north-central and west-central populations, where morphological traits do not show the strong differentiation detected by molecular characters. Our results highlight the need for integrative taxonomic studies, not only to delimitate taxonomic units but also for a better and more comprehensive understanding of population variability and differentiation.

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