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The Global Volcanism Program has no activity reports for Escanaba Segment.
The Global Volcanism Program has no Weekly Reports available for Escanaba Segment.
The Global Volcanism Program has no Bulletin Reports available for Escanaba Segment.
The linear, N-S-trending Escanaba Segment, the southernmost of the Gorda Ridge, lies immediately north of the Mendocino Francture Zone off the coast of northern California. The axial crest of the 130-km-long segment, also known as the Escanaba Trough, is about 3-5 km wide at the northern end and increases to 18 km to the south near the junction with the Mendocino FZ. The rift valley floor of the slow-spreading segment lies at about 3200 m depth, bounded by faulted walls about 1500 m high with unusual gold-bearing massive sulfide deposits in sediment hills at the base of the scarps uplifted by volcanic sills or lacoliths. Thick sediment deposits from the continental margin enter the axial trough from the fracture zone and thin to the north. A preliminary uranium-series date of Holocene age was obtained from a basaltic lava flow in the axial valley in the less-sedimented northern part.
Summary of Holocene eruption dates and Volcanic Explosivity Indices (VEI).
|Start Date||Stop Date||Eruption Certainty||VEI||Evidence||Activity Area or Unit|
|2260 BCE (?)||Unknown||Confirmed||0||Uranium-series||40 deg 59 min North|
The Global Volcanism Program has no synonyms or subfeatures listed for Escanaba Segment.
|A NOAA/PMEL map shows the setting of the Escanaba Segment at the southern end of the Gorda Ridge west of the coast of northern California. The linear, N-S-trending segment is the southernmost of the five segments of the Gorda Ridge and lies immediately north of the Mendocino Francture Zone. The axial crest of the 130-km-long segment, also known as the Escanaba Trough, is about 3-5 km wide at the northern end and widens to 18 km to the south near the junction with the Mendocino Fracture Zone.
Courtesy of NOAA NeMo Observatory.
The following references have all been used during the compilation of data for this volcano, it is not a comprehensive bibliography. Discussion of another volcano or eruption (sometimes far from the one that is the subject of the manuscript) may produce a citation that is not at all apparent from the title.
Davis A S, Clague D A, White W M, 1998. Geochemistry of basalt from Escanaba Trough: evidence for sediment contamination. J Petr, 39: 841-858.
Goldstein S J, Murrell M T, Janecky D R, Delaney J R, Clague D A, 1992. Geochronology and petrogenesis of MORB from the Juan de Fuca and Gorda ridges by 238U-230Th disequilibrium. Earth Planet Sci Lett, 109: 255-272.
Tormanen T O, Koski R A, 2005. Gold enrichment and the Bi-Au association in the pyrrhotite-rich massive sulfide deposits, Escanaba Trough, southern Gorda Ridge. Econ Geol, 100: 1135-1150.
Volpe A M, Goldstein S J, 1993. 236Ra-230Th disequilibrium in axial and off-axis mid-oecan ridge basalts. Geochim Cosmochim Acta, 57: 1233-1241.