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Rotation Forcing of Tectonics and Climate
Valentin Krassilov,
Sophia Barinova,
Svyatoslav Rybnikov
Issue:
Volume 3, Issue 3, June 2014
Pages:
68-75
Received:
3 June 2014
Accepted:
18 June 2014
Published:
30 June 2014
Abstract: Contrary to predictions of the tidal torque model, length of day (LOD) decreases over a series of fluctuations since 1960s at least. The so far deepest LOD depression of 1997 – 2010 corresponds to the most prominent rises of total seismic activity and global mean temperatures. A conspicuously flat interval of the LOD curve uniformly at or slightly below –0.1 ms level in 2001 – 2005 roughly coincides with the similarly flattened high plateaus of total seismicity (2002 – 2008) and temperature anomalies (2002 – 2007), indicating causal relationships. Pearson correlation coefficients about –0.5 (p ≈ 0.03) for both LOD/earthquake frequencies and LOD/temperature anomalies are raised to –0.76 (p = 0.002) and –0.71 (p = 0.001) respectively on supposition of about two year lag between rotation forcing and the maximal geophysical effects. Non-random earthquake frequency distribution between the geoid rises and depressions is clear evidence of rotation forcing, with about 60% significant earthquakes over the highest equatorial Papua – Solomon Islands rise. The world largest ophiolite massive in the central part of the rise marks the area of mantle upheaval, coinciding with the ‘critical Niño3.4 region’ of operational WMO definitions. El Niño years prevail over the high plateau of temperature dynamics. These observations are meaningful in respect to the model of rotational forcing at the base of concerted global change. The mass/angular momentum transfer with magmatic activity is seen as a stabilizing feedback, with a lag about 2.5 years preliminarily inferred from a case study of El Niño /Mount Etna eruption dynamics.
Abstract: Contrary to predictions of the tidal torque model, length of day (LOD) decreases over a series of fluctuations since 1960s at least. The so far deepest LOD depression of 1997 – 2010 corresponds to the most prominent rises of total seismic activity and global mean temperatures. A conspicuously flat interval of the LOD curve uniformly at or slightly ...
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Remote Sensing and GIS Contribution to the Detection of Coastal Slope Failure in the Safi Area, Morocco
El Bchari,
Fatima,
Theilen-Willige,
Barbara,
Ait Malek Halima
Issue:
Volume 3, Issue 3, June 2014
Pages:
76-84
Received:
29 May 2014
Accepted:
17 June 2014
Published:
30 June 2014
Abstract: Located in the urban area, the cliff of Sidi Bouzid and Amouni shows slope instabilities due to falls and collapse blocks and rotational block gliding. These phenomena form a risk to the economic, social, cultural and environmental issues. Geomorphologic, lithologic and tectonic conditions (ie surfaces of discontinuities such as fractures) combined with the influence of marine abrasion explain the increased instability of this part of the Sahel - Safi. This ongoing slope failure is a handicap for coastal development projects. The activity of these phenomena -more or less remarkable- is monitored by the GIS integrated observation and evaluation of field, aerial and satellite data, allowing to establish synthesis maps that give a risk assessment in this sector. Digital Elevation Model (ASTER_GDEM2) is used for the morphometric analysis of this area and as a base for the weighted overlay of causal / preparatory morphometric factors influencing the slope stability.
Abstract: Located in the urban area, the cliff of Sidi Bouzid and Amouni shows slope instabilities due to falls and collapse blocks and rotational block gliding. These phenomena form a risk to the economic, social, cultural and environmental issues. Geomorphologic, lithologic and tectonic conditions (ie surfaces of discontinuities such as fractures) combined...
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Cenozoic Eruptive Stratigraphy and Structure in Taiz area of Yemen
Abdul-Hamid Malek,
Mysore Ramachandraiah Janardhana,
Abdul-Aleam Ahmed Al-Qadhi
Issue:
Volume 3, Issue 3, June 2014
Pages:
85-96
Received:
3 June 2014
Accepted:
26 June 2014
Published:
10 July 2014
Abstract: The present study focuses on the field description of a bimodal volcanic rock centre and fault types present in Taiz area located in the southern part of Yemen. Taiz area serves as one of the key areas to understand the Afro-Arabian bimodal volcanism and the emplacement of Afar plume and the relationship between extension tectonics and magmatism. Taiz area comprises bimodal volcanic rocks encompassing mafic and silicic lava flows and pyroclastic rocks. The lava flows were erupted in five phases – three major basic and two acid phases. Lower basalt sequence (Tb1) is the oldest and main phase of flood basalt volcanism, formed as part of a wide spread volcanism within the Afro-Arabian region. This is followed by lower silicic sequence phase (Tr1) consisting of varied assortment of lithologies such as rhyolite flows with subordinate ignimbrites, welded ash, pyroclastic breccia, and random pumice and obsidian. The middle basalt sequence phase (Tb2) has been formed from the flows fed by fissure-dyke systems and separated from Tr1 by red colored weathering band of saprolitic bole (paleosol). The latest silicic sequence phase (Tr2) with limited exposures in the region, comprises rhyolitic plug domes, rhyolitic lava flows and locally welded and unwelded volcaniclastic deposits. In places, the silicic volcanic rocks have been diagenetically altered to bentonitic clay minerals and zeolites. The youngest phase of volcanic rocks represented by the basaltic rocks in the region (Tb3) is exposed in few outcrops along the southeastern slope of the mapped area and conformably capping the Tr2. It includes the basaltic flows intercalated with mafic conglomerate and tuff layers. The study area has been subjected to tensional tectonic regime throughout much of the Tertiary and extensions led to volcanism, granitic rock intrusions and formation of structural elements such as normal faults and deep joints. NW, NE, and E-W are the three major trends of faults recognized and these are related to the progressive rifting of Red Sea and Gulf of Aden.
Abstract: The present study focuses on the field description of a bimodal volcanic rock centre and fault types present in Taiz area located in the southern part of Yemen. Taiz area serves as one of the key areas to understand the Afro-Arabian bimodal volcanism and the emplacement of Afar plume and the relationship between extension tectonics and magmatism. T...
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