Diamond potentiality in the kimberlites of the Batain Nappes, Eastern Oman

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1 Diamond potentiality in the kimberlites of the Batain Nappes, Eastern Oman Project Code: Funds: Funding Source: (SR/SCI/ETHS/06/01) 50,000 OMR His Majesty s Trust Fund Start Date: 02 May 2006 Duration: 3 years Team Members: Researchers Research Assistants Graduate Students Dr. Sobhi Jaber Nasir (PI) Mr. Hamdan Seif Al-Zidi Mr. Abdullah Said Al-Hakamani Dr. Salah Al-Khirbash Mr. Seif Amer Al-Mamari Mr. Seif Al-Amri Dr. Hugh Rollinson Mr. Mohamed Said Al-Hakamani Dr. Abdulrhaman Ali Al-Harthy Mr. Ahmed Al-Ghanbusi Dr. Abdulrazak Sediq Al-Sayigh Mr Younis Rashid Al-Habsi Dr. Ali Ibrahim Lazki Dr. Mubarik Ali Ali Consultants Prof. Hans-Joachim Massone Dr. Thomas Theye Dr. Felix Kaminsky Executive Summary Objectives The only known economically significant primary sources of diamond are kimberlites and some carbonatites. The presence of diamonds in a kimberlite can only be determined with confidence by the collection and processing of a large and representative sample. The present project aims to assess the potential of the kimberlites to yield diamond and the potential of carbonatites to yield REE and P. The two principal objectives are Phase I: Potentiality of diamond in the kimberlite : Phase II: Further exploration, mapping, sampling and detailed petrological investigations to look for urther localities where similar rocks should be sought within the Oman Mountains Methods The two principal methods used in prospecting for kimberlites are sampling for soil, rocks and resistant (indicator) minerals and a number of geophysical techniques. Exploration will enable target selection, sampling for microdiamonds, drilling and evaluation as well as interpretation of aerial photographs and, aeromagnetic data in the Asseelah area together with reconnaissance field mapping as well as rock and soil sampling on a 2km x 2km grid This will be followed by detailed description of the mineralogy and texture of rocks,, detailed ground magnetic and gravity surveys out over selected magnetic targets, geochemical analysis of indicator minerals by electron microprobe, geochemical analysis of rock samples (XRF, ICP-MS), geochronology, evaluation and reporting Results: 1- Asseelah and Bomethra area, Eastern Oman

2 The main body of the ultramafic lamprophyres occurs in a diatreme at the coast of the Asseelah village, northeastern Oman. The second major outcrops of ultramafic lamprophyres occur as several 6 km long dykes at the Bomethra area. The lamprophyric sill and dyke swarms of the Bomethra area comprise macrocrystic, spinel and phlogopite bearing hybabyssal facies calcite aillikites/damtjernites with pelletal lapilli and globular segregationary textures. The petrography, mineralogy, trace element and isotopic composition of the dyke rocks are comparable to aillikites and damtjernites with kimberlitic affinity. Kimberlite indicator minerals include chromite, Crdiopside, G4 garnet, and picroilmenite. The Asseelah and the Bomethra ultramafic rocks are enriched in light REE and have a high modal proportion of Ti-Al rich phlogopite, suggesting that they were derived from a source region which has experienced melt-depletion followed by metasomatic enrichment. 2- Wadi Sal Two occurrence of carbonatites have been discovered within Batain nappes in the western and in the eastern parts of the Wadi Sal southeastern part of Oman. They range in composition from ferruginous carbonatites to magnesio carbonatites. A distinctive aspect of the Sal carbonatites is the presence of anomalously high REE and P2O5 content ( ppm; wt. % P2O5; eastern sal; ppm REE and 2-3 wt.% P2O5; western Sal). 3- Al-Huqf area Cambro-Ordovician highly potassik alkaline magmatism is exposed in four small laccolithic intrusions in the Huqf area of Central Oman. The source of the magmas has many similarities to that of EM1 oceanic island basalts. The petrogenesis of the suite is therefore explained by mixing of melts derived by small degree partial melting of previously enriched garnet- and spinelperidotite-facies mantle sources. Conclusions: 1. The Asseelah aillikites and carbonatites known to date by their mineralogical features are unlikely to diamondiferous. Mineral indicators of high diamond potential are absent in grains analyzed from heavy mineral concentrates and polished sections. 2. The Bomethra aillikites, damtjernite and carbonatites show good potentiality to be diamondiferous. These rocks contain several diamond indicator minerals, mainly Crdiopside, phlogopite, chromite and ilmenite, some of which lies within the diamond inclusion field. 3. The Asseelah and Bomethra ultramafic rocks are also enriched with REE which could be of economic interest.

3 Management of Salt-Affected Soils and Water for Sustainable Agriculture Project Code: Funds: Funding Source: (SR/AGR/SWAE/06/01) 95,000 OMR His Majesty s Trust Fund Start Date: 02 May 2006 Duration: 4 years Team Members: Researchers Research Assistants Graduate Students Dr. Salim Ali Al-Rawahy (P.I.) Dr. Nazir Hussein Mr. Hamed Sulaiman Al-Dhuhli Dr. Mushtaque Ahmed (Co-P.I.) Mr. Mohammed Hassan Mansur Mr. Said Shannan Al-Khalasi Dr. Ahmed Nasser Al-Bakri Mrs. Basma Nasser Al-Sheidhani Mr. Khalid Rashid Al-Mahrazi Dr. Slim Zekri Mr. Amrou Saleh Al-Oulqi Mr. Ali Mohammed Naifer Dr. Hayder A. AbdelRahman Mrs. Alia Saleh Al-Hinai Mr. Mohammed Hamoud Al-Owaisi Prof. Osman Mahgoub Gaafar Mr. Mohammed Said Al-Mazrui Mr. Saud Seif Al-Habsi Mr. Waleed Salim Al-Abri Dr. Yasin Ahmed Al-Mulla Mr. Hamed Soud Al-Sheidhani Dr. Said Salim Al-Esmaily Mr. Said Khalfan Al-Maashari Dr. Rashid Abdulla Al-Yahyai Mr. Said Hamed Al-Saqri Dr. Malik Mohammed Al-Wardy Ms. Sharifa Said Al-Hashmi Mr.Hamdan Salim Al-Waheibi Mr. Ishaq Ahmed Al-Anqudi Mr.Mahmood Khalfan Al-Rashdi Dr. Nazir Hussein Dr. Saleem Kassim Nadaf Mrs. Maryam AbdullaAl-Hassani Dr. Stephen Goddard Ms. Nafisa Mahmoud Dr. Shabbir A. Shahid Mr. Saif Sulaiman Al-Jabri Dr. Jam'aan Rabea Shammas Mr. Abdulla Said Al-Buloshi Dr. Ahmed Salim Al-Busaidi Mr. Mansur Hamed Al-Haddabi Dr. Ali Hussein Al-Lawati Mr. Khalid Salim Al-Abri Dr. Abdulla Mohammed Al-Saadi Mr. Mahmoud Juma Al-Obeidani Mr. Salim Mohammed Al-Khanbashi Ms. Lamya Darwish Al-Balushi Prof. Humphrey Esechie Dr. Salim Ali Al-Jabri Executive Summary Ms. Zakiyya Abdulla Al-Alawi Mr. Salim Khamis Al-Jabri Mr. Yahya Khamis Al-Yahyai Objective The project aimed at developing management guidelines which are scientifically sound for farmers to sustain economically viable agricultural production in salt affected areas with saline groundwater. Methods Scientifically sound management practices were experimented in field plots with saline soils, underlained with saline groundwater at the Agricultural Research Center of the Ministry of Agriculture (MoA) at Rumais. The trials were multidisciplinary in nature and provided unique opportunities for five graduate students to obtain the MS degrees. The following studies were conducted: Advanced techniques such as satellite images and geographical information systems were used to quantify the extent of salinization over the years.

4 Agronomic methods combined with modern irrigation methods were evaluated to determine optimal combinations resulting in increased productivity and minimal salinization. Feeding trials of Omani sheep confirmed that fodder grown in saline soils with saline water have no negative impact on their growth or their meat quality. Incorporation of aquaculture in saline areas was proven feasible and profitable. Socio-economic study of the rural society, was carried out in which over 120 farmers at Agricultural Developmental Centers of the Ministry of agriculture in the Wilayats of Barka, Musan a, Suwaiq, Khaboura, Sohar and Shinas made invaluable contributions. This study reflects the very existence of the rural society, was one of the main objectives of the project. It involved holding workshops with the farmers at Agricultural Development Centers of the Ministry, their salt-affected farms visited and detailed information gathered for the study. These results of all the above studies were confirmed by analyzing over 2,000 soil, water, fodder, fish and meat samples produced during trials which helped understand the nature of the situation better. Results: Remote sensing and GIS techniques in assessing the degree and extent of the Al- Batinah Region has given good indication of its precision and effectiveness in terms of speed and low cost. (Figure 1) Trials confirmed that salt-tolerant varieties of tomatoes, barley, sorghum and pearl millet can be grown successfully in prevailing conditions (up to 9 ds/m irrigation water). Two varieties of pearl millet were selected for their superiority in both salinity and heat tolerances. (Figures 2, 3, 4, 5) Intermittent leaching in soil resulted in good plant growth. Mulching surface soil with a thin layer of shredded date palm residues resulted in lesser salt accumulation in the soil resulting in more crop yield than other methods. (Figure 6) Results show that feeding fodder grown on highly saline conditions (up to 9 ds/m irrigation water) to Omani sheep had neither adversely affected their health nor meat quality. (Figure 7) Preliminary study on integrating aquaculture in saline agriculture shows that it could improve economic return since it is another food source for the farmers. In addition, residual water that come out of fish ponds is rich in nutrients and could be used to irrigate crops in salt-affected farms. (Figure 8) Economic losses inflicted to farmers due to land salinity has been evaluated in terms of gross margin for three types of farms. The damage caused by salinity was obtained through comparison of three types of farms. In the low salinity farms the profit was 2,197 OR/ha, while it reached only 1,581 RO/ha in the medium salinity farms. Farms with high salinity irrigation water registred the lowest profit with only 638 OR/ha, or 71% less than the low salinity farms. Discussions among SQU team, with our colleagues in the MoA and farmers demonstrated that farmers are receptive in scientifically sound guidelines. The farmers responded very positively and highly appreciated the efforts by the SQU-MoA team. Conclusions Sound management practices of saline soil and water in this study have shown great potential for sustainable agriculture in the Al-Batinah. This justifies a growing need to utilize land and water resources which are of marginal quality for growing salt-tolerant crops in the Al-Batinah where there is increasing demand on the limited water resources. This would contribute towards agricultural sustainability, food security and combating desertification and maintaining social cohesion of rural community.

5 Family and genetic understanding of autosomal recessive disorders: a clinical genetic, cytogenetic, molecular and linkage study in Oman (famguardinoman): Dr Aisha Al-Khayat Biology, College of Science This research will clarify the genetic causes in Oman of several serious autosomal recessive (AR) diseases of the retina and of the central nervous system. We will carry out a population study of Single Nucleotide Polymorphisms (SNPs) in Omanis, comparing results with published SNP findings from other countries. We will then use that data, plus detailed clinical and family data from consanguineous Omani families with ophthalmological or developmental disorders, to confirm or exclude AR inheritance using linkage analysis. Micro-array based gene chip studies of SNP markers covering the whole genome will provide the population data as well as identifying sites of SNP homozygosity in affected people. Also, we will check for chromosomal microdeletions or duplications in affected individuals using metaphase-based Comparative Genomic Hybridisation (CGH). We estimate that the population SNP study and SNP investigations in the highly informative Omani families, as well as metaphase CGH, will localize the site of a causative AR gene in a majority of the 50 families to be studied or identify micro-deletions or duplications.