Short-term variations in the distribution of hydrothermal plumes along a superfast spreading center, East Pacific Rise, 27 300–32 200S
نویسندگان
چکیده
[1] A multidisciplinary expedition to the southern East Pacific Rise (27 300–32 200S) provided an opportunity to compare the efficiency and effectiveness of two methods for mapping hydrothermal plumes: the standard conductivity-temperature-depth-optical (CTDO) tow-yo method and a towed fixed array of hydrographic and optical sensors (Miniature Autonomous Plume Recorders (MAPRs)). Six second-order segments were mapped twice: once with CTDO tow-yos, and then again with a fixed array of MAPRs attached to the cable of a deep-towed side-scan sonar. We found a high degree of overall agreement between the two methods in both the distribution and optical intensity of hydrothermal plumes. Betweensurvey differences increased as time between surveys increased from <0.5 to >6 days, presumably because of advection of the plumes by local currents. Plume locations changed by as much as 10 km, implying a confidence limit in predicting vent site location using segment-scale hydrothermal plume surveys. Towed MAPR arrays proved an efficient and effective method for acquiring coregistered geological and hydrothermal plume data.
منابع مشابه
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a r t i c l e i n f o Keywords: East Pacific Rise mid-ocean ridge oceanic crust off-axis magmatism waveform modeling Formation of oceanic crust along the East Pacific Rise is thought to be complete within a few kilometers of the rise axis. Here, however, we present evidence for magmatism 20 km from the spreading center in 300-ka-old crust. Seismic data reveal an intrusive complex ~ 2 km beneath...
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