Geochemistry of mantle-related volcanic rocks from the Tibbit Hill volcanic suite, Quebec Appalachians The 554 Ma Tibbit Hill volcanic suite in the Humber zone of the Quebec Appalachians is exposed along a belt about 250 km long in southern Quebec and northern Vermont. It contains minor felsic and intermediate lithologies with predominantly basaltic compositions, and represents a clear example of a rift-related volcanic shield. This petrological-geochemical investigation is aimed at establishing the exact magma source and its possible relation to mantle plumes, and determining the petrological processes of magma evolution. Work in progress. A. M. Abdel-Rahman and P.S. Kumarapeli.* (Supported by URB.) The Wadi Dib ring complex, eastern Egypt: A mantle derived A-type suite This study focuses on the use of isotopic and rare-earth geochemical characteristics of the Wadi Dib alkaline ring complex, to interpret its source and evolution, as well as its rare-metal potentials. A 7-point Rb-Sr isochron defines an age of 578± 16 Ma. Field relations, combined with major and trace-element studies confirmed the concentric zonation of the various lithologic units. Geochemical modelling will be used to test a mantle source for its magma and the degree of contamination by crustal materials. One paper is currently under review, and another is in preparation. A. M. Abdel-Rahman and W. Frisch*. Exceptional preservation and community development around deep-water fissures in the Cenomanian of Lebanon The work has examined the geochemistry, sedimentology and paleoecology of the four known horizons of exceptional preservation in the Cretaceous of Lebanon, which are famous for their high-quality fossil fish and invertebrate biotas. Work has shown a linkage of these features to the development of synsedimentary fissuring within the sediments and geochemical evidence suggests these provided nutrients which enabled a chemo-autrophic community to develop in a low-oxygen deep water environment. A manuscript has been submitted for publication. P. A. Allison* and C. D. Walley. The stratigraphy of Yemen The Mesozoic stratigraphy of Yemen is now known to be much more complex twas earlier thought thanks to exploration drilling and seismic surveys which have revealed patterns of Mesozoic basins hidden under a blanket of Tertiary. Unfortunately the high level of drilling activity by different operating companies has produced a plethora of names. This official study will thoroughly revise the stratigraphic nomenclature for unified Yemen and is being carried out with the assistance of Yemeni geological colleagues with the view of issuing an enlarged and comprehensive International Lexicon of Stratigraphy for Yemen. Work is in its final write up stage; publication by the International Union of Geological Sciences is expected shortly. Z. R. Beydoun. (Supported by the Ministry of Petroleum and Mineral Resources, Yemen; Mayfair Petroleum Ltd.) Miocene stratigraphy and sedimentology of Ras Chekka This ongoing project will create a detailed sedimentological and micropaleontological log for the important Miocene section of Ras Chekka, North Lebanon. This is important as the Lebanon area underwent considerable tectonism before, during and after the Miocene. Dating and sedimentology of these rocks will help constrain the models for the evolution of Lebanon. This regionally important sequence is little known and this will be the first detailed study of it. Sampling to start Summer 1997. M. Bou Fadel* and C. D. Walley. (Supported by University College, London.) Rehabilitation of water resources in Lebanon Work continues on a major study to plan the use of national water resources for the future. This work involves an assessment of the current and projected needs of the various areas in Lebanon against their water resources and suggests hydrologic and hydrogeologic strategies to ensure the optimum use of the available water. A number of technical reports have already been produced. J. Davey* and N. Aker. (Supported by Council for Development and Rehabilitation; Ministry of Hydroelectric and Energy Resources). National water quality surveillance: Nahr Ibrahim project The project is concerned with the utilization of surface waters to meet increased water demands. The study includes: a) mapping the Lebanese rivers to determine the source and types of contaminants; b) determining the quality of surface water for drinking, agricultural, industrial and recreational activities and c) assessment of the self-purification capacity of the rivers. The study started by surveying the Nahr Ibrahim, as it is the second largest river in Lebanon after the Litani, and constitutes a potential source of water for the suburbs and cities north of Beirut. Currently the project is directed towards studying the five major water basins (rivers, lakes). Actual analytical work is targeted to start early July 1997. M. Jurdi and K. Khair. (Supported by LNSCR.) The crustal structure of the Eastern Mediterranean Basin This project is studying the nature and structure of the Eastern Mediterranean crust using multiple source Werner deconvolution estimates and comparing the results with those of earlier geophysical and geological studies. A paper will be submitted for publication shortly. K. Khair and G. Tsokas*. Earthquake seismology of Lebanon and surrounding areas This project is studying the tectonic framework and earth structures of the eastern Mediterranean area using the available elastic velocity and attenuation data for the region. Data collection is currently underway. K. Khair, P. Hatzidimitriu*, G. Tsokas* and C. Papazachos*. The crustal structure of the northern Levant Region This project studied the crustal structure of Lebanon and Syria using multiple source Werner deconvolution estimates of Bouguer gravity anomalies. These results are then analysed and compared with existing geological and geophysical studies. Research completed with one paper published. K. Khair and G. Tsokas*. River profiles and active tectonics along the Dead Sea Fault System in Lebanon The project uses geological and topographic maps supported by field studies to assess the relative displacement along those major faults of Lebanon that fan outwards from the Dead Sea Transform Fault at the northern end of the Hula Depression. The main emphasis is on the displacement of drainage patterns and other relevant geomorphologic features along faults. A publication will be written shortly. K. Khair and S. Spencer. The nature, age and petrogenesis of the Cartier Batholith, northern flank of the Sudbury structure, Ontario Based on over two hundred samples collected from the Cartier complex, we examine the petrological-mineralogical characteristics of the various igneous phases, their field relations and chemical nature. Using the U-Pb-Zircon isotopic system, we obtained an age of emplacement of 2608+11/-8 Ma, which is approximately 100 Ma after the Kenoran Orogeny. The aim of the study was to determine the petrogenesis of this batholith, and illustrate its relation to the Levack high-grade gneiss complex which hosts this batholith. One paper accepted for publication. A. Meldrum*, A. M. Abdel-Rahman, R. F. Martin*, and N. Wadicka*. (Supported by URB.) A micropaleontological biostratigraphy of the Lebanese Jurassic The Jurassic sequence in Lebanon is one of the thickest (over 2 km) and most complete in the Middle East region. Unusually it also appears to show a continuous section through Jurassic-Cretaceous boundaries and possibly also the Triassic-Jurassic. The work, still in the planning and initial sampling stages, will seek to examine the microfauna of the succession to assign precise ages to the sequence. Results will be used to clarify the age ranges of a number of important species. M. D. Simmons* and C. D. Walley. Structure and tectonics of Lebanon This wide-ranging project is examining the complex structural effects of the Late Cenozoic strike slip activity along the Dead Sea Transform Fault System in Lebanon. This fault activity, which has operated over a number of different fault segments at differing times, continues to the present day. Analysis of how these processes have worked, based on field data and remote sensing studies, will help determine details of timing, direction and amounts of motion of regional tectonic processes over the last 10 Ma. It will also clarify the important issue of national seismic risk. One article is in press, another has been submitted. S. Spencer, R. H. W Butler* and H. Griffith*. (Supported by National Environment Research Council, UK). Structure and stability of the non-transform offsets on the Mid Atlantic Ridge between 24° N and 30° N This project is based on the interpretation of new side scan sonar data from the Mid Atlantic Ridge. The nature of the segmentation and the segment offsets were examined in order to determine the structure and long term stability of the discontinuities. Paper submitted. S. Spencer, D. K. Smith*, R.J. Cann*, J. Linn* and E. McAllister*. (Supported by National Environment Research Council; Royal Society; National Science Foundation; ONR; URB.) Geomorphology and tectonics in Lebanon Complex and major tectonic events involving vertical and lateral displacement of crustal units have taken place in Lebanon over the last 10-20 million years. These events are recorded in the way that the landscape features have been uplifted and eroded. This ongoing work, involving field studies and remote sensing data, involves relating specific landform features such as stream profiles to tectonic events. S. Spencer. Geological history of the Levantine margin This project is examining the sedimentological, stratigraphic and tectonic history of the Lebanon margin from the Early Jurassic onwards, and includes preparation of paleogeographic maps for the region. Work so far has demonstrated important and previously overlooked pre-Late Miocene structuring which pre-dates the strike-slip deformation of the Late Cenozoic. This work forms the basis of the Lebanese contribution to the International Geological Correlation Program Project 369 “Comparative Evolution of Peri-Tethyan Rift Basins”. One paper in preparation; one conference abstract has been produced. C. D. Walley. (Supported by URB.) Teaching Earth Sciences in Lebanon This project has been stimulated by the recent addition of the Earth Sciences to the Lebanese national school curriculum. Despite an excellent national geology there are few, if any, resources available for teachers to place concepts within a Lebanese context. The work, done in conjunction with the Science and Math Education Center at AUB, is seeking to create appropriate resources for teachers. One presentation has been given, an article is being prepared and a number of handouts for schools produced. C. D. Walley. Linkages between Cenozoic tectonism and paleoclimatic changes in the Middle East area This ongoing research aims to analyze the relationship between tectonic events in the region and the marked climate changes over the last forty million years. During this time the Arabian area has gone from being a continental promontory covered by shallow marine seas, to an increasingly landlocked and arid area surrounded on most sides by mountains. It is hoped that this work can be extended by coring Pleistocene-Recent lacustrine sediments in the Bekaa valley. One presentation given, one paper is now in press. C. D. Walley. Apatite in the Sudbury igneous complex, Ontario: Monitor of fractionation and degassing Apatite
is present as an accessory mineral in all phases of the layered Sudbury
igneous complex, which is a host of the world-class nickel deposits. This
mineral is found primarily as a post-cumulus phase, but becomes cumulus
mineral in the quartz gabbro. Cathodoluminescence and Rb-Sr isotopic data
reflect that apatite is generally homogeneous. These, along with rare-earth
elements, fluorine, chlorine and other chemical data will be used to interpret
the source and origin of its magma. Questions such as whether the complex
evolved by fractionation processes of a single or multiple magmas, and
whether the magma is the result of an impact-generated crustal melt or
was related to volcanism will be addressed. Work is in progress. S.
Warner*, R. F. Martin* and A.M. Abdel-Rahman (Supported
by Natural Sciences and Engineering Research Council of Canada; URB.)
Abdel-Rahman, A.M., Tectonic stages of shield evolution: The Pan-African belt in the northern Nubian shield. Tectonophysics, 242, 223-240, 1995 ———, Pan-African volcanism: Petrology and geochemistry of the Dokhan volcanic suite in the northern Nubian Shield. Geological Magazine, 133, 17-31, 1995. ———, Mineralogy of chlorites in a spectrum of igneous rocks. Mineralogical Magazine, 59, 129-141, 1996. ———, Discussion on the comment on nature of biotites in alkaline, calc-alkaline and peraluminous magmas. Journal of Petrology, 37, 1031- 1035, 1996. Beydoun, Z. R., Productive Middle East clastic oil and gas reservoirs: their depositional settings and origins of their hydrocarbons. In Sedimentary facies analysis; a tribute to the research and teaching of Harold G. Reading, A.G. Plint (ed), International Association of Sedimentologists, Special Publication 22, 331-354, 1995. ———, Prehistoric, ancient and mediaeval occurrences and uses of hydrocarbons in the greater Middle East region. Journal of Petroleum Geology, 20, 1. 91-95. 1997. Beydoun, Z. R., As-Saruri, M. L.* and Baraba, R.S.*, Sedimentary basins of the Republic of Yemen: their structural evolution and geological characteristics. Revue de l'Institute Français du Petrole, 51, 6, 763-775, 1996. Davey, J.* and Aker, N., Geology in Lebanon. Geoscientist, 3, 7-9, DATE Khair, K., Tsokas, G.* and Sawaf, T.*, Crustal structure of northern Levant region: Multiple source Werner deconvolution estimates for Bouguer gravity anomalies. Geophysical Journal International, 128, 605-616, 1997. Miller*,
R. R. and Abdel-Rahman, A.M., The Kings Point complex, Insular Newfoundland,
and its potential for rare-metal mineralization. Newfoundland Mines
and Energy: Current Research, 95-1, 159-175, 1995.
ABSTRACTS, CONFERENCES AND PROCEEDINGS Abdel-Rahman, A.M. and Kumarapeli, P.S. *, Petrological and geochemical evolution of intermediate volcanic rocks from the Tibbit Hill volcanic suite, Quebec Appalachians. Geological Association of Canada-Mineralogical Association of Canada, Program with Abstract, 22, A2, 1997. Abdel-Rahman, A.M. and Miller, R. *, Geochemical affinities of the volcanic members of the Flowers River cauldron complex, Labrador. Geological Association of Canada-Mineralogical Association of Canada, Program with Abstract, 20, A5. 1995 Khair, K. Diachronic fluctuations of precipitation in the Eastern Mediterranean. Proceedings of the First International Conference on Computer Simulation, 99-109, Beirut, Lebanon, 1995. Khair, K and Ibrahim A.W.*, The velocity of elastic p waves in unconsolidated material under low pressures. International Workshop on High-Resolution Geophysics, Tucson, Arizona, USA, 1997. Khair, K. and Skokan, C.*, The quantitative influence of salinity on the apparent resistivity on a physical-model salination. Proceedings of the Symposium on the Application of Geophysics to Engineering and Environmental Problems (SAGEEP), 111-120, Keystone, Colorado, USA, 1996. Meldrum*, A., Abdel-Rahman, A.M. and Martin*, R.F., Petrogenesis of the Cartier Batholith, Sudbury, Ontario: A crust-derived I-type Archean suite. Geological Association of Canada – Mineralogical Association of Canada, program with Abstract, 20, A70, 1995. Miller*, R. and Abdel-Rahman, A.M., Peralkalinity and Pearce element ratio analysis of metasomatized subaerial felsic volcanic rocks. Geological Association of Canada–Mineralogical Association of Canada, Program with Abstract, 20, A71, 1995. Tsokas, G.* and Khair, K., Crustal structure in Lebanon and Syria as inferred by multiple source Werner deconvolution estimates. First Congress of the Balkan Geophysical Society, Athens, Greece 1996. Walley, C. D., Geological issues of the Lebanese coast. Inaugural Conference of the National Council for Scientific Research, National Center for Marine Sciences, Batroun, Lebanon, 1996. ———, From oceanic promontory to continental interior: The 40-million-year history of the desiccation of Arabia. Past, Present and Future of the Middle East Desert, Yarmouk, Jordan, 1996. ———, Teaching Earth Science concepts in Lebanon: some comments. First Science and Math Conference on the Role of Science and Math Teachers in Developing and Implementing the School Curricula, American University of Beirut, May 1997. ———, The evolution of the Tethys and the history of the Lebanon region (abstract). Comparative Evolution of Peri-Tethyan Rift Basins Third Annual Meeting, Cairo, Egypt (1996), 44-45, 1997. Warner,
S.*, Martin, R.F.*, and Abdel-Rahman, A.M., Apatite in the Sudbury igneous
complex, Ontario: Monitor of fractionation and degassing. Geological
Association of Canada–Mineralogical Association of Canada, Program with
Abstract, 21, A100, 1996.
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