Metamorphosed and metasomatized basalts, and unmetamorphosed equivalents, were recovered from the steep slopes of Bald Mountain, a north-south elongated seamount lying 60 km west of the Median Rift Valley at 45° N. Block faulting and uplift of the seamount, together with the removal by submarine erosion of extrusive rocks capping the seamount, have resulted in the exposure of the more deep-seated metamorphosed horizons along the fault scarps. The block-faulted nature of Bald Mountain, indicative of brittle fracturing of the upper crustal layers of the Mid-Atlantic Ridge, may be a result of the low ocean floor spreading rates implied from age determinations and magnetic anomaly patterns at 45° N.

From 1983 until 1989 NOAA-NCEI compiled the NOAA-MMS Marine Minerals Geochemical Database from journal articles, technical reports and unpublished sources from other institutions. At the time it was the most extended data compilation on ferromanganese deposits world wide. Initially published in a proprietary format incompatible with present day standards it was jointly decided by AWI and NOAA to transcribe this legacy data into PANGAEA. This transfer is augmented by a careful checking of the original sources when available and the encoding of ancillary information (sample description, method of analysis...) not present in the NOAA-MMS database.

Supplement to: Aumento, Fabrizio; Loncarevic, B D (1969): The Mid-Atlantic Ridge near 45° N. III. Bald Mountain. http://store.pangaea.de/Projects/NOAA-MMS/e69-002.pdf, Canadian Journal of Earth Sciences, 6(1), 11-23