scholarly journals On the Origin of Orphan Tremors & Intraplate Seismicity in Western Africa

2021 ◽  
Author(s):  
Tolulope Morayo Olugboji ◽  
Manoochehr Shirzaei ◽  
Yingping Lu ◽  
Adekunle Abraham Adepelumi ◽  
Folarin Kolawole
Keyword(s):  
Intraplate Seismicity ◽  
Western Africa

scholarly journals On the Origin of Orphan Tremors and Intraplate Seismicity in Western Africa

2021 ◽  
Vol 9 ◽  
Author(s):  
T. Olugboji ◽  
Manoochehr Shirzaei ◽  
Yingping Lu ◽  
A. A. Adepelumi ◽  
F. Kolawole
Keyword(s):  
Seismic Station ◽  
Capital City ◽  
Intraplate Seismicity ◽  
Fracture Zones ◽  
Induced Earthquakes ◽  
Tectonic Inheritance ◽  
Western Africa ◽  
Seismic Records ◽  
Shed Light ◽  
Regional Tectonics

On September 5–7, 2018, a series of tremors were reported in Nigeria’s capital city, Abuja. These events followed a growing list of tremors felt in the stable intraplate region, where earthquakes are not expected. Here, we review available seismological, geological, and geodetic data that may shed light on the origin of these tremors. First, we investigate the seismic records for parent location of the orphan tremors using a technique suitable when a single-seismic station is available such as the Western Africa region, which has a sparse seismic network. We find no evidence of the reported tremors within the seismic record of Western Africa. Next, we consider the possibility of a local amplification of earthquakes from regional tectonics, reactivation of local basement fractures by far-field tectonic stresses, post-rift crustal relaxation, landward continuation of oceanic fracture zones, or induced earthquakes triggered by groundwater extraction. Our assessments pose important implications for understanding Western Africa’s intraplate seismicity and its potential connection to tectonic inheritance, active regional tectonics, and anthropogenic stress perturbation.

scholarly journals On the Origin of Orphan Tremors & Intraplate Seismicity in Western Africa

2021 ◽  
Author(s):  
Tolulope Morayo Olugboji ◽  
Manoochehr Shirzaei ◽  
Yingping Lu ◽  
Adekunle Abraham Adepelumi ◽  
Folarin Kolawole
Keyword(s):  
Intraplate Seismicity ◽  
Western Africa

INTRAPLATE SEISMICITY IN THE MID-ATLANTIC US

2016 ◽  
Author(s):  
Lillian Soto-Cordero ◽  
◽  
Anne S. Meltzer ◽  
Josh Stachnik
Keyword(s):  
Intraplate Seismicity

scholarly journals The climatic imprint of bimodal distributions in vegetation cover for western Africa

2016 ◽  
Vol 13 (11) ◽  
pp. 3343-3357 ◽  
Author(s):  
Zun Yin ◽  
Stefan C. Dekker ◽  
Bart J. J. M. van den Hurk ◽  
Henk A. Dijkstra
Keyword(s):  
Land Cover ◽  
Congo Basin ◽  
Shortwave Radiation ◽  
Mean Annual Precipitation ◽  
Above Ground Biomass ◽  
Precipitation Regime ◽  
Ground Biomass ◽  
Western Africa ◽  
Precipitation Regimes ◽  
Woody Cover

Abstract. Observed bimodal distributions of woody cover in western Africa provide evidence that alternative ecosystem states may exist under the same precipitation regimes. In this study, we show that bimodality can also be observed in mean annual shortwave radiation and above-ground biomass, which might closely relate to woody cover due to vegetation–climate interactions. Thus we expect that use of radiation and above-ground biomass enables us to distinguish the two modes of woody cover. However, through conditional histogram analysis, we find that the bimodality of woody cover still can exist under conditions of low mean annual shortwave radiation and low above-ground biomass. It suggests that this specific condition might play a key role in critical transitions between the two modes, while under other conditions no bimodality was found. Based on a land cover map in which anthropogenic land use was removed, six climatic indicators that represent water, energy, climate seasonality and water–radiation coupling are analysed to investigate the coexistence of these indicators with specific land cover types. From this analysis we find that the mean annual precipitation is not sufficient to predict potential land cover change. Indicators of climate seasonality are strongly related to the observed land cover type. However, these indicators cannot predict a stable forest state under the observed climatic conditions, in contrast to observed forest states. A new indicator (the normalized difference of precipitation) successfully expresses the stability of the precipitation regime and can improve the prediction accuracy of forest states. Next we evaluate land cover predictions based on different combinations of climatic indicators. Regions with high potential of land cover transitions are revealed. The results suggest that the tropical forest in the Congo basin may be unstable and shows the possibility of decreasing significantly. An increase in the area covered by savanna and grass is possible, which coincides with the observed regreening of the Sahara.

Key drivers of avifauna in greenspace of institutional campuses in a state in Western Africa

2021 ◽  
pp. 127092
Author(s):  
Panshak S. Kumdet ◽  
Samuel T. Ivande ◽  
Filibus Danjuma Dami
Keyword(s):  
Western Africa ◽  
Key Drivers

Diagnosis and successful treatment of an Austrian dog infected with Trypanosoma congolense forest type

2021 ◽  
Vol 49 (02) ◽  
pp. 142-147
Author(s):  
Michael Leschnik ◽  
Katja Silbermayr ◽  
Abigail Guija ◽  
Barbara Nell
Keyword(s):  
Clinical Improvement ◽  
Successful Treatment ◽  
Initial Treatment ◽  
Blood Smear ◽  
Forest Type ◽  
Trypanosoma Congolense ◽  
Lethal Outcome ◽  
Complete Eradication ◽  
Western Africa ◽  
Mongrel Dog

AbstractCanine African Trypanosomosis (CAT) is a rarely described disease with frequently lethal outcome. A 5-year-old female mongrel dog weighing 22 kg was presented in Austria due to unilateral uveitis, pancytopenia, and anorexia 4 months after return from a trip through Western Africa. Trypanosoma spp. flagellates were detected in a blood smear and identified as Trypanosoma congolense forest type by PCR. Initial treatment with imidocarb and miltefosine led to clinical improvement but only isometamidium chloride hydrochloride applied intramuscularly led to complete eradication of the pathogen from the dog’s blood 4 months later.

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