(Report on the results of regional prospecting, performed in the Ray-Rubat an Nisab area in 1977-1978).

(Report on the results of regional prospecting, performed in the Ray-Rubat an Nisab area in 1977-1978).

Conclusion:

For the reported period, the group of soviet geologist jointly with Yemeni specialist has performed regional prospecting of 1:50000, 1:100000 scale in Ray-Rubat area at about 500sq.km. The group has done more than it was programmed, new date has been obtained on wide development of metamorphosed volcanogenic formations in the Ray-Rubat area, on the presence of supposedly Mesozoic terrigene – carbonate complex. The team revealed a number of occurrences of non –ferrous and precious metals (Abyan, Kashet), mineralized and silicified zones (Hatib, Mashoba, Shattba, Self). Non-metallic mineral occurences (the Lakhraman Ray occurences of amphibole-asbestos, the Bengal – of cermic pegmatites) and a number of geochemical haloes of non-farrous, rare and precious metals. The final negative estimation has been given to the Nisab type rare – metal – rare – earth pegmatite granites and pegmatites, to the Farshah titanomagnetite, occurrence, to the Charib siderite occurrence and to Antary ΙΙ rare –metal – rare – earth occurrences.

The targets on the frothing study of the promising localities and zones, their priority and method of recommended operations have been dismissed in the appropriate chapters of the report. In this view, we dwell only on main conclusions and recommendation as for further trend of study in the reported area.

The Abyan gold occurrence, the kashet silver – polymetallic and Hatib

For further investigation.

The Mashoba and Shatoba zones of phyllite – like sulphidized schists are the localities of the second priority, requiring small volume investigation at the initial stage, consisting of drilling 3-4 boreholes, 100-150 m deep, surface geochemical prospecting at the flanks and further detailization of individual localities. Further detailed investigation of the zones is recommended only if the economic importance of the Kashet zone has been established (as these zones prove to be its close analogues) or if ore zones are revealed at the recommended stage of their prospecting.

Detailed prospecting of 1:10000 scale at the Rey and Laohraman asbestos occurrences. The Laohraman occurrence is the locality of the first order priority. The development of long –fibrous amphibole – asbestos in the form of veinlets and lenticular accumulations has been established here.

It is recommended to continue the study of metallogenic specialization of the terrigene – carbonate complex of the supposedly Mesozoic age, within the limits of which a number of points of their active hydrothermally – metasomatic working (amphibolizaton resulting in the formation of asbestos veinlets of sulphasalt, secondary silicificeation and pyritization) has been revealed.

The branch of Lawdar sheet zone from the latitude of lawdar Araba in the west to the boundary of the investigated area in the east of 7-10km wide and 25-30km in extension has not been investigated at all and warrant regional prospecting of 1:50000 –

1:100000scales.