Paleomagnetic and magnetostructural study of Jurassic formations of Gara Djebilet (Tindouf Basin, Southwestern Algeria)

International audienceRecent geochemical analyzes and 40Ar/39Ar datings of dolerite sills and dykes and basalticlava flows from Southwestern Algeria (Tindouf, Reggane, Bechar and Hank basins) haveshown that these rocks are related to the Central Atlantic Magmatic Province (CAMP). TheCAMP is one of the largest among the Mesozoic basaltic provinces identified and formed about200 Ma ago as a preamble to the breakup of Pangea. These data were solid arguments for undertakinggeological observations and sampling for paleomagnetic studies and magnetic fabrics onthe CAMP formations. A network of three long doleritic dykes (198.9 ± 1.8 Ma) located in theTindouf Basin were targeted to clarify the structural context of their emplacement (magneticfabrics) and to determine a new reliable Mesozoic pole.The magnetic fabric, in almost all the sections sampled, is defined mainly through groupingof k1 and k2 axes on the dyke plane whereas axis k3 is almost perpendicular to the dykeplane. This fabric can therefore be interpreted as the magma flow direction. The new Jurassicpaleomagnetic pole, of excellent quality, is very close to those obtained on detrital formationsof the Algerian Sahara and close to those recently determined on igneous formations of Morocco.This new pole is also very close to the North African pole at 200 Ma. These results representa new contribution for a better knowledge of the geodynamic context during this period

Paleomagnetic and magnetostructural study of Jurassic formations of Gara Djebilet (Tindouf Basin, Southwestern Algeria)

International audienceRecent geochemical analyzes and 40Ar/39Ar datings of dolerite sills and dykes and basalticlava flows from Southwestern Algeria (Tindouf, Reggane, Bechar and Hank basins) haveshown that these rocks are related to the Central Atlantic Magmatic Province (CAMP). TheCAMP is one of the largest among the Mesozoic basaltic provinces identified and formed about200 Ma ago as a preamble to the breakup of Pangea. These data were solid arguments for undertakinggeological observations and sampling for paleomagnetic studies and magnetic fabrics onthe CAMP formations. A network of three long doleritic dykes (198.9 ± 1.8 Ma) located in theTindouf Basin were targeted to clarify the structural context of their emplacement (magneticfabrics) and to determine a new reliable Mesozoic pole.The magnetic fabric, in almost all the sections sampled, is defined mainly through groupingof k1 and k2 axes on the dyke plane whereas axis k3 is almost perpendicular to the dykeplane. This fabric can therefore be interpreted as the magma flow direction. The new Jurassicpaleomagnetic pole, of excellent quality, is very close to those obtained on detrital formationsof the Algerian Sahara and close to those recently determined on igneous formations of Morocco.This new pole is also very close to the North African pole at 200 Ma. These results representa new contribution for a better knowledge of the geodynamic context during this period

Paleomagnetic and magnetostructural study of Jurassic formations of Gara Djebilet (Tindouf Basin, Southwestern Algeria)

International audienceRecent geochemical analyzes and 40Ar/39Ar datings of dolerite sills and dykes and basalticlava flows from Southwestern Algeria (Tindouf, Reggane, Bechar and Hank basins) haveshown that these rocks are related to the Central Atlantic Magmatic Province (CAMP). TheCAMP is one of the largest among the Mesozoic basaltic provinces identified and formed about200 Ma ago as a preamble to the breakup of Pangea. These data were solid arguments for undertakinggeological observations and sampling for paleomagnetic studies and magnetic fabrics onthe CAMP formations. A network of three long doleritic dykes (198.9 ± 1.8 Ma) located in theTindouf Basin were targeted to clarify the structural context of their emplacement (magneticfabrics) and to determine a new reliable Mesozoic pole.The magnetic fabric, in almost all the sections sampled, is defined mainly through groupingof k1 and k2 axes on the dyke plane whereas axis k3 is almost perpendicular to the dykeplane. This fabric can therefore be interpreted as the magma flow direction. The new Jurassicpaleomagnetic pole, of excellent quality, is very close to those obtained on detrital formationsof the Algerian Sahara and close to those recently determined on igneous formations of Morocco.This new pole is also very close to the North African pole at 200 Ma. These results representa new contribution for a better knowledge of the geodynamic context during this period

A new Jurassic paleomagnetic data and emplacementconditions study of the CAMP Gara Djebilet dykes (TindoufBasin, Southwest Algeria).

International audienceThe Central Atlantic Magmatic Province (CAMP) is one of the largestidentified Mesozoic basalt provinces formed approximately 200 Ma ago as a preambleto the Pangea dismemberment. Recent 40Ar/39Ar dating and geochemical analyses ofdolerite sills and dykes and basalt lava flows in southwestern Algeria (Bechar area,Reggane, Hank and Tindouf basins) showed that these rocks are parts of the CAMP.These data represented good arguments to perform geological field observations andsampling for paleomagnetic and magnetic fabric (AMS) investigations in the Tindoufbasin CAMP formations. Three NE-SW oriented long doleritic dykes (198.9 ±1.8 Ma)in this basin were targeted in order to find out the structural context of theiremplacement (magnetic fabric) and to determine a new reliable Jurassic pole. Themagnetic fabric, in almost the whole sampled sections, is defined mainly by clusteringof k1 and k2 axes on the dyke plane whereas the k3 axis is nearly perpendicular to it.This fabric is therefore interpreted as due to magma flow. The new Jurassicpaleomagnetic pole, of a good quality, is very close to those obtained from coevaldetrital Algerian Saharan formations and those recently determined from coevalMoroccan igneous formations, it is also very close to the 200 Ma mean African pole.These results constitute a considerable contribution to a more precise knowledge of thegeodynamical context during this period

Paleomagnetic and magnetostructural study of the Gara Djebilet Jurassic magmatic formations (Tindouf Basin, Southwest Algeria)

International audienceRecent geochemical analyses and 40Ar/39Ar dating of dolerite sills and dykes and basalt lava flows in southwesternAlgeria (Tindouf, Reggane, Bechar area and Hank basins) showed that these rocks are linked to the CentralAtlantic Magmatic Province (CAMP). The later is one of the largest identified Mesozoic basalt provinces formedapproximately 200 Ma ago as a preamble to the Pangea dismemberment. These data were strong arguments toundertake geological field observations and a sampling for paleomagnetic and magnetic fabric study in CAMPprovince formations. Three long doleritic dykes (198.9 1.8 Ma) in the Tindouf basin were targeted in order topoint out the structural context of their emplacement (magnetic fabric) and to determine a new reliable Mesozoicpole. The magnetic fabric, in almost the whole sampled sections, is defined mainly by clustering of k1 and k2axes on the dyke plane whereas the k3 axis is nearly perpendicular to it. This fabric is therefore interpreted as dueto magma flow. The new Jurassic paleomagnetic pole, of excellent quality, is very close to those obtained fromcoeval detrital Algerian Saharan formations and also close to those recently determined from coeval Morrocan igneousformations. It is very close to the 200 Ma mean NW African pole too. These results represent a considerablecontribution of to a better knowledge of the geodynamical context during this period

A new Jurassic paleomagnetic data and emplacementconditions study of the CAMP Gara Djebilet dykes (TindoufBasin, Southwest Algeria).

International audienceThe Central Atlantic Magmatic Province (CAMP) is one of the largestidentified Mesozoic basalt provinces formed approximately 200 Ma ago as a preambleto the Pangea dismemberment. Recent 40Ar/39Ar dating and geochemical analyses ofdolerite sills and dykes and basalt lava flows in southwestern Algeria (Bechar area,Reggane, Hank and Tindouf basins) showed that these rocks are parts of the CAMP.These data represented good arguments to perform geological field observations andsampling for paleomagnetic and magnetic fabric (AMS) investigations in the Tindoufbasin CAMP formations. Three NE-SW oriented long doleritic dykes (198.9 ±1.8 Ma)in this basin were targeted in order to find out the structural context of theiremplacement (magnetic fabric) and to determine a new reliable Jurassic pole. Themagnetic fabric, in almost the whole sampled sections, is defined mainly by clusteringof k1 and k2 axes on the dyke plane whereas the k3 axis is nearly perpendicular to it.This fabric is therefore interpreted as due to magma flow. The new Jurassicpaleomagnetic pole, of a good quality, is very close to those obtained from coevaldetrital Algerian Saharan formations and those recently determined from coevalMoroccan igneous formations, it is also very close to the 200 Ma mean African pole.These results constitute a considerable contribution to a more precise knowledge of thegeodynamical context during this period

Paleomagnetic and magnetostructural study of the Gara Djebilet Jurassic magmatic formations (Tindouf Basin, Southwest Algeria)

International audienceRecent geochemical analyses and 40Ar/39Ar dating of dolerite sills and dykes and basalt lava flows in southwesternAlgeria (Tindouf, Reggane, Bechar area and Hank basins) showed that these rocks are linked to the CentralAtlantic Magmatic Province (CAMP). The later is one of the largest identified Mesozoic basalt provinces formedapproximately 200 Ma ago as a preamble to the Pangea dismemberment. These data were strong arguments toundertake geological field observations and a sampling for paleomagnetic and magnetic fabric study in CAMPprovince formations. Three long doleritic dykes (198.9 1.8 Ma) in the Tindouf basin were targeted in order topoint out the structural context of their emplacement (magnetic fabric) and to determine a new reliable Mesozoicpole. The magnetic fabric, in almost the whole sampled sections, is defined mainly by clustering of k1 and k2axes on the dyke plane whereas the k3 axis is nearly perpendicular to it. This fabric is therefore interpreted as dueto magma flow. The new Jurassic paleomagnetic pole, of excellent quality, is very close to those obtained fromcoeval detrital Algerian Saharan formations and also close to those recently determined from coeval Morrocan igneousformations. It is very close to the 200 Ma mean NW African pole too. These results represent a considerablecontribution of to a better knowledge of the geodynamical context during this period

A new Jurassic paleomagnetic data and emplacementconditions study of the CAMP Gara Djebilet dykes (TindoufBasin, Southwest Algeria).

International audienceThe Central Atlantic Magmatic Province (CAMP) is one of the largestidentified Mesozoic basalt provinces formed approximately 200 Ma ago as a preambleto the Pangea dismemberment. Recent 40Ar/39Ar dating and geochemical analyses ofdolerite sills and dykes and basalt lava flows in southwestern Algeria (Bechar area,Reggane, Hank and Tindouf basins) showed that these rocks are parts of the CAMP.These data represented good arguments to perform geological field observations andsampling for paleomagnetic and magnetic fabric (AMS) investigations in the Tindoufbasin CAMP formations. Three NE-SW oriented long doleritic dykes (198.9 ±1.8 Ma)in this basin were targeted in order to find out the structural context of theiremplacement (magnetic fabric) and to determine a new reliable Jurassic pole. Themagnetic fabric, in almost the whole sampled sections, is defined mainly by clusteringof k1 and k2 axes on the dyke plane whereas the k3 axis is nearly perpendicular to it.This fabric is therefore interpreted as due to magma flow. The new Jurassicpaleomagnetic pole, of a good quality, is very close to those obtained from coevaldetrital Algerian Saharan formations and those recently determined from coevalMoroccan igneous formations, it is also very close to the 200 Ma mean African pole.These results constitute a considerable contribution to a more precise knowledge of thegeodynamical context during this period

Paleomagnetic and magnetostructural study of the Gara Djebilet Jurassic magmatic formations (Tindouf Basin, Southwest Algeria)

International audienceRecent geochemical analyses and 40Ar/39Ar dating of dolerite sills and dykes and basalt lava flows in southwesternAlgeria (Tindouf, Reggane, Bechar area and Hank basins) showed that these rocks are linked to the CentralAtlantic Magmatic Province (CAMP). The later is one of the largest identified Mesozoic basalt provinces formedapproximately 200 Ma ago as a preamble to the Pangea dismemberment. These data were strong arguments toundertake geological field observations and a sampling for paleomagnetic and magnetic fabric study in CAMPprovince formations. Three long doleritic dykes (198.9 1.8 Ma) in the Tindouf basin were targeted in order topoint out the structural context of their emplacement (magnetic fabric) and to determine a new reliable Mesozoicpole. The magnetic fabric, in almost the whole sampled sections, is defined mainly by clustering of k1 and k2axes on the dyke plane whereas the k3 axis is nearly perpendicular to it. This fabric is therefore interpreted as dueto magma flow. The new Jurassic paleomagnetic pole, of excellent quality, is very close to those obtained fromcoeval detrital Algerian Saharan formations and also close to those recently determined from coeval Morrocan igneousformations. It is very close to the 200 Ma mean NW African pole too. These results represent a considerablecontribution of to a better knowledge of the geodynamical context during this period