@article {jackson_sonar_2022,
	title = {Sonar Observation of Heat Flux of Diffuse Hydrothermal Flows},
	journal = {Earth and Space Science},
	volume = {9},
	number = {n/a},
	year = {2022},
	note = {_eprint: https://onlinelibrary.wiley.com/doi/pdf/10.1029/2021EA001974},
	pages = {e2021EA001974},
	abstract = {Previous work using multibeam sonar to map diffuse hydrothermal flows is extended to estimate the heat output of diffuse flows. In the first step toward inversion, temperature statistics are obtained from sonar data and compared to thermistor data in order to set the value of an empirical constant. Finally, a simple model is used to obtain heat-flux density from sonar-derived temperature statistics. The method is applied to data from the Cabled Observatory Vent Imaging Sonar (COVIS) deployed on the Ocean Observatories Initiative{\textquoteright}s Regional Cabled Array at the ASHES vent field on Axial Seamount. Inversion results are presented as maps of heat-flux density in MW/m2 and as time series of heat-flux density averaged over COVIS{\textquoteright} field of view.},
	keywords = {Deep-Sea Hydrothermal, Heat flux, sonar},
	issn = {2333-5084},
	doi = {10.1029/2021EA001974},
	url = {https://onlinelibrary.wiley.com/doi/abs/10.1029/2021EA001974},
	author = {Jackson, Darrell and Bemis, Karen and Xu, Guangyu and Ivakin, Anatoliy}
}
@article {RN192,
	title = {Acoustic and In-situ Observations of Deep Seafloor Hydrothermal Discharge: an OOI Cabled Array ASHES Vent Field Case Study},
	journal = {Earth and Space Science},
	year = {2020},
	type = {Journal Article},
	abstract = {The Cabled Observatory Vent Imaging Sonar (COVIS) was installed on the Ocean Observatories Initiative{\textquoteright}s Regional Cabled Array observatory at ASHES hydrothermal vent field on Axial Seamount in July 2018. The acoustic backscatter data recorded by COVIS in August{\textendash}September 2018, in conjunction with in situ temperature measurements, are used to showcase and verify the use of COVIS for long-term, quantitative monitoring of hydrothermal discharge. Specifically, sonar data processing generates three-dimensional backscatter images of the buoyant plumes above major sulfide structures and two-dimensional maps of diffuse flows within COVIS{\textquoteright}s field-of-view. The backscatter images show substantial changes of plume appearance and orientation that mostly reflect plume bending in the presence of ambient currents and potentially the variations of outflow fluxes. The intensity of acoustic backscatter decreases significantly for highly bent plumes as compared to nearly vertical plumes, reflecting enhanced mixing of plume fluids with seawater driven by ambient currents. A forward model of acoustic backscatter from a buoyancy-driven plume developed in this study yields a reasonable match with the observation, which paves the way for inversely estimating the source heat flux of a hydrothermal plume from acoustic backscatter measurements. The acoustic observations of diffuse flows show large temporal variations on time scales of hours to days, especially at tidal frequencies, but no apparent long-term trend. These findings demonstrate COVIS{\textquoteright}s ability to quantitatively monitor hydrothermal discharge from both focused and diffuse sources to provide the research community with key observational data for studying the linkage of hydrothermal activity with oceanic and geological processes.},
	keywords = {acoustic, axial seamount, hydrothermal, imaging, observatory, sonar},
	doi = {10.1029/2020ea001269},
	url = {https://app.dimensions.ai/details/publication/pub.1133310442},
	author = {Xu, Guangyu and Bemis, Karen and Jackson, Darrell and Ivakin, Anatoliy}
}
@article {RN10,
	title = {Observation and Modeling of Hydrothermal Response to the 2015 Eruption at Axial Seamount, Northeast Pacific},
	journal = {Geochemistry, Geophysics, Geosystems},
	number = {ja},
	year = {2018},
	type = {Journal Article},
	abstract = {The 2015 eruption at Axial Seamount, an active volcano at a depth of 1500 m in the Northeast Pacific, marked the first time a seafloor eruption was detected and monitored by an in situ cabled observatory{\textemdash}the Cabled Array, which is part of the Ocean Observatories Initiative. After the onset of the eruption, eight cabled and noncabled instruments on the seafloor recorded unusual, nearly synchronous and spatially uniform temperature increases of 0.6{\textendash}0.7{\textdegree}C across the southern half of the caldera and neighboring areas. These temperature signals were substantially different from those observed after the 2011 and 1998 eruptions at Axial and hence cannot be explained by emplacement of the 2015 lava flows on the seafloor. In this study, we investigate several possible explanations for the 2015 temperature anomalies and use a numerical model to test our preferred hypothesis that the temperature increases were caused by the release of a warm, dense brine that had previously been stored in the crust. If our interpretation is correct, this is the first time that the release of a hydrothermal brine has been observed due to a submarine eruption. This observation would have important implications for the salt balance of hydrothermal systems and the fate of brines stored in the subsurface. The observation of the 2015 temperature anomalies and the modeling presented in this study also demonstrate the importance of contemporaneous water column observations to better understand hydrothermal impacts of submarine eruptions.},
	issn = {15252027},
	doi = {10.1029/2018gc007607},
	url = {https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2018GC007607},
	author = {Xu, Guangyu and Chadwick, William W. and Wilcock, William S. D. and Bemis, Karen G. and Delaney, John}
}
