Iron monosulphide globules and tubes grown in the laboratory have similar morphologies to the fossil pyrite botryoids and chimneys found in the Silvermines exhalative sedimentary ore-body of Carboniferous age in Ireland. We envisage analogous fine structures growing at hot springs (100-200°C) in the earliest oceans as having provided the culture chambers and flow reactors for life to originate by phosphorylation and growth of organic molecules on the iron sulphide surfaces. Such sulphide structures grown in the laboratory could be used in origin-of-life experiments. We: a hypothesis, System. Appl. Microbiof., 10,207-210. Wachtershauser G. (1988b) Before enzymes and templates: theory of surface metabolism, Minobiol. Reviews, 52,452-484. Wachtershauser G. (1988c) Deutsches Patentamt 3812158, FRG. Wark E.E. and Wark I.W. (1935) The physical chemistry of flotation. VI the adsorption of amines by sulfide minerals, J. Phys. Chem., 39,1021-1030. Windley B.F., S i p s o n P.R. and Muir M.D. (1984) The role of atmospheric evolution in Precambrian metallogenesis, Fortschr. Miner., 62, 99,712-720. 253-267.

The geothermal setting of the archaeological site at Aghia Kyriaki, Southeast Melos (or Milos) was investigated in order to help clarify the possible role of the site in mineral exploitation on Melos in Roman times. There are active sulfurous fumaroles in the area and these were also potential sources of sulfur and alum-group minerals in Roman times. However, geothermal activity has been ongoing in Southeast Melos for hundreds of thousands of years, and extensive hydrothermal alteration of basement rocks to the northeast of the site has produced "white rocks" containing additional potential industrial minerals such as kaolin and alunite. The archaeological remains occur within, but mainly near the surface, of a deeply gullied sequence of late Quaternary alluvial sediments, which consist mainly of metamorphic detritus but are rich in sulfates; the remains contain pottery sherds through the entire sequence of about 40 m. They were deposited on an earlier gullied topography of felsic tuffs overlying the metamorphic basement. Pervasive and veinlike intense reddish alteration of these sediments is probably mainly due to superheated fluid escaping from depth. Field observations demonstrate that this took place after the main phase of building but was likely to be ongoing during occupation of the site. While industrial minerals and geothermal energy would therefore have been available in the Roman period, any relationship of the site to mineral exploitation will have to be determined by archaeological excavation. ᭧

No abstract

From Mr C. N. Okezie: The writer recently mapped a small portion (about 200 square miles) of the basement complex of the Kafanchan area, in the Nigerian Younger Granite province. He also mapped a very small Younger Granite stock, the Nok granite, within this area. As a result of this work it became apparent to the writer that the trends of some intrusive Older Granites, their consanguineous granitic pegmatite dykes and sills, and the few basic dykes found in the area appear to have been controlled by four main structural planes of weakness in the basement rocks. These planes are the roughly north-south schistosity and foliation and three inferred sets of master-joints striking roughly nw–se, ne–sw , and e -w. Careful examination of the Younger Granite complexes of this province as seen on the 1 : 2 000 000 geological map of Nigeria or on pl. vii of the Society’s Memoir .No . 1 shows also that these four planes of weakness appear to have exercised a significant control in the emplacement of the Younger Granites. This is shown by the fact that groups of these complexes are often aligned while individual complexes are often elongated parallel to any one of these four directions. The position is illustrated as follows: Aligned complexes (1) Banke-Kudaru-Rishua-Kerku-Nok-Afu (N-S) (2) Banke-Liruei-Suku-Tongolo-Dagga Allah-Kwandon-Kaya-Kofayi ( nw-se ) (3) Kwandon-Kaya-Jos-Bukuru-Vom-Kagoro ( ne -sw) (4) Burra-Ningi-Kila-Wurji-Fagam ( e -w) (5) Zuku-Saiya-Shokobo-Jere-Sanga-Buji-Jos-Bukuru-Rop ( n-s ) (6) Sara-Fier-Sha-Kaleri-South-Mada-Afu ( ne-sw ) Elongated complexes (1) Liruei, Kwandon-Kaya, Kofayi ( nw-se ) (2) Afu, Fagam ( ne -sw) (3) Sara–Fier, Nok, Rishua, Kudaru ( n––s ) (4)