In this study we assessed the current status of coral reefs along the Saudi Arabian coast of the Red Sea. Among the three growth forms of Acroporid corals, the branching forms were found to dominate in the Farassan Is...In this study we assessed the current status of coral reefs along the Saudi Arabian coast of the Red Sea. Among the three growth forms of Acroporid corals, the branching forms were found to dominate in the Farassan Islands （44.55%±11.10% cover） fol-lowed by tabular forms in the Doga Islands （ranging between 18%±6.47% and 18.30%±9.47% cover）. Digitate forms were rarely found along the coast except at Maqna. Among the five growth forms of non-Acroporid corals, we observed maximum cover of branching forms in the Yanbu offshore area （58.89%±15.11% cover） followed by the Jeddah coast （24.76%±14.04% cover）. The Millepora spp., a non-Scleractinian coral, was abundant at all the near-shore sites, such as Jeddah （10.70%±8.21%） and A1-Wajh （9.81%±6.69%）. The live coral cover （including both Scleractinian and non-Scleractinian corals） of Saudi Red Sea coast was seen to be higher in the north and gradually decrease towards the south. Principal Component analysis showed that the contribution of Acro- porid corals was greater in the southern region than in the northem and middle regions, but vice-versa in the case of non-Acroporid corals. Bray-Curtis cluster analysis categorized all the study sites into two major clusters with 60% similarity. Among them, one cluster-forming sites from Maqna to Masturah （Northem region） and the second one comprised the middle and southem regions （Jeddah to Farassan Islands）, and one outlier Rabigh.展开更多
This application note discusses the preliminary results of paleomagnetics studies of several incisions of the Paleozoic period the territory of Armenia and neighboring regions （Minor Caucasus）. It is supposed that b...This application note discusses the preliminary results of paleomagnetics studies of several incisions of the Paleozoic period the territory of Armenia and neighboring regions （Minor Caucasus）. It is supposed that before the Permian period the Armenian-lranian Mezocontinent was uniform with Afro-Arabia and only at the end of the late Paleozoic the formed Mesozoic ocean separated these areas from each other. A result of application of the complex laboratory investigations were identified from samples of primary magnetization the direction of which corresponds to the time of formation of the studied rocks. On the basis of paleomagnetic researches of Triassic, Permian, Devonian, Carbonian rocks a preliminary conclusion has been made about the dipole configuration of the geomagnetic field throughout Paleozoic. The comparison of the obtained data to paleomagnetic definitions of African, Arabian plates, Europe and the Siberian platform leads to the conclusion that the Minor Caucasus existed separately from the present general lithosphere blocks of Greater Caucasus and Europe.展开更多
文摘In this study we assessed the current status of coral reefs along the Saudi Arabian coast of the Red Sea. Among the three growth forms of Acroporid corals, the branching forms were found to dominate in the Farassan Islands （44.55%±11.10% cover） fol-lowed by tabular forms in the Doga Islands （ranging between 18%±6.47% and 18.30%±9.47% cover）. Digitate forms were rarely found along the coast except at Maqna. Among the five growth forms of non-Acroporid corals, we observed maximum cover of branching forms in the Yanbu offshore area （58.89%±15.11% cover） followed by the Jeddah coast （24.76%±14.04% cover）. The Millepora spp., a non-Scleractinian coral, was abundant at all the near-shore sites, such as Jeddah （10.70%±8.21%） and A1-Wajh （9.81%±6.69%）. The live coral cover （including both Scleractinian and non-Scleractinian corals） of Saudi Red Sea coast was seen to be higher in the north and gradually decrease towards the south. Principal Component analysis showed that the contribution of Acro- porid corals was greater in the southern region than in the northem and middle regions, but vice-versa in the case of non-Acroporid corals. Bray-Curtis cluster analysis categorized all the study sites into two major clusters with 60% similarity. Among them, one cluster-forming sites from Maqna to Masturah （Northem region） and the second one comprised the middle and southem regions （Jeddah to Farassan Islands）, and one outlier Rabigh.
文摘This application note discusses the preliminary results of paleomagnetics studies of several incisions of the Paleozoic period the territory of Armenia and neighboring regions （Minor Caucasus）. It is supposed that before the Permian period the Armenian-lranian Mezocontinent was uniform with Afro-Arabia and only at the end of the late Paleozoic the formed Mesozoic ocean separated these areas from each other. A result of application of the complex laboratory investigations were identified from samples of primary magnetization the direction of which corresponds to the time of formation of the studied rocks. On the basis of paleomagnetic researches of Triassic, Permian, Devonian, Carbonian rocks a preliminary conclusion has been made about the dipole configuration of the geomagnetic field throughout Paleozoic. The comparison of the obtained data to paleomagnetic definitions of African, Arabian plates, Europe and the Siberian platform leads to the conclusion that the Minor Caucasus existed separately from the present general lithosphere blocks of Greater Caucasus and Europe.
