Biogeochemical Exploration of the Pescadero Basin Vents

In 2015, the deepest high-temperature hydrothermal vents in the Pacific Ocean (3,700 m) were discovered in a sediment-covered pull-apart basin along the Pescadero Transform Fault in the Gulf of California. Biological communities were observed thriving among the carbonate chimney structures (Figure 1; Goffredi et al., 2017). As a result of their striking contrast to other hydrothermal systems, the high- temperature, high-carbon Pescadero Basin vents provided the opportunity to examine the influence of tectonic setting on the nature of seafloor vent sites, the fundamental geochemical controls on biological colonization in the deep ocean, and the role of fluid venting on global-scale ocean chemistry and climate. In November 2017, with support from the Dalio Ocean Initiative, a multidisciplinary science team led by Woods Hole Oceanographic Institution scientists set out on E/V Nautilus to investigate this area of active venting

Biogeochemical Exploration of the Pescadero Basin Vents

In 2015, the deepest high-temperature hydrothermal vents in the Pacific Ocean (3,700 m) were discovered in a sediment-covered pull-apart basin along the Pescadero Transform Fault in the Gulf of California. Biological communities were observed thriving among the carbonate chimney structures (Figure 1; Goffredi et al., 2017). As a result of their striking contrast to other hydrothermal systems, the high- temperature, high-carbon Pescadero Basin vents provided the opportunity to examine the influence of tectonic setting on the nature of seafloor vent sites, the fundamental geochemical controls on biological colonization in the deep ocean, and the role of fluid venting on global-scale ocean chemistry and climate. In November 2017, with support from the Dalio Ocean Initiative, a multidisciplinary science team led by Woods Hole Oceanographic Institution scientists set out on E/V Nautilus to investigate this area of active venting

Massive asphalt deposits, oil seepage, and gas venting support abundant chemosynthetic communities at the Campeche Knolls, southern Gulf of Mexico

Hydrocarbon seepage is a widespread process at the continental margins of the Gulf of Mexico. We used a multidisciplinary approach, including multibeam mapping and visual seafloor observations with different underwater vehicles to study the extent and character of complex hydrocarbon seepage in the Bay of Campeche, southern Gulf of Mexico. Our observations showed that seafloor asphalt deposits previously only known from the Chapopote Knoll also occur at numerous other knolls and ridges in water depths from 1230 to 3150 m. In particular the deeper sites (Chapopopte and Mictlan knolls) were characterized by asphalt deposits accompanied by extrusion of liquid oil in form of whips or sheets, and in some places (Tsanyao Yang, Mictlan, and Chapopote knolls) by gas emission and the presence of gas hydrates in addition. Molecular and stable carbon isotopic compositions of gaseous hydrocarbons suggest their primarily thermogenic origin. Relatively fresh asphalt structures were settled by chemosynthetic communities including bacterial mats and vestimentiferan tube worms, whereas older flows appeared largely inert and devoid of corals and anemones at the deep sites. The gas hydrates at Tsanyao Yang and Mictlan Knolls were covered by a 5-to-10 cm-thick reaction zone composed of authigenic carbonates, detritus, and microbial mats, and were densely colonized by 1–2 m-long tube worms, bivalves, snails, and shrimps. This study increased knowledge on the occurrences and dimensions of asphalt fields and associated gas hydrates at the Campeche Knolls. The extent of all discovered seepage structure areas indicates that emission of complex hydrocarbons is a widespread, thus important feature of the southern Gulf of Mexico

Munidopsis geyeri and M. exuta (Crustacea: Munidopsidae): A study of two deep-sea, amphi-Atlantic species that co-occur in the southern Gulf of Mexico

Este artículo contiene 35 páginas, 6 figuras, 5 tablas.The history of colonization and dispersal of fauna among deep-sea chemosynthetic ecosystems remains enigmatic and poorly understood. The distribution of squat lobsters of the genus Munidopsis Whiteaves, 1874 can be influenced by the rich organic matter and associated organism communities of chemosynthetic ecosystems. The present work analyzed the molecular relationships and morphology of individuals from different populations of Munidopsis exuta Macpherson & Segonzac, 2005 and M. geyeri Pequegnat & Pequegnat, 1970 in such ecosystems along the Atlantic Equatorial Belt, including the Chapopote Knoll, in the southern Gulf of Mexico. Munidopsis geyeri is re-described based on the present findings and reference to the literature. This analysis documented the genetic distances, as well as range of variation in the diagnostic characters that support the separation of M. exuta and M. geyeri. Our results confirm that the two species coexist in seep ecosystems and have an amphi-Atlantic distribution.The national and international projects that funded the present research included collaborations between the Re-search Center Ocean Margins (RCOM) of Bremen University, Germany, Study of the process related with fluid seep-age in oceanic ground (E project); the Instituto de Ciencias del Mar y Limnología, UNAM, Mexico, for open access payment; Factores que definen la variabilidad de la diversidad biológica y biomasa en el mar profundo del Golfo de México (PAPIIT), CONACyT 40158F. Molecular analysis was supported by the international collaboration between the University of Louisiana at Lafayette under funding to Darrly L. Felder from U.S. National Science Foundation grants NSF/BS&I DEB-0315995 and NSF/AToL EF-0531603, as well as from Texas A&M University and the Cen-tre d’Estudis Avançats de Blanes (CEAB-CSIC). RR wishes to acknowledge PRODEP-SEP, Mexico, through the program “Apoyo a la Incorporación de NPTC” (Ago/1/2018– Jul/31/2019). Illustrations of Mundiopsis geyeri (Figs 6C, D, E, I, J and N) were produced by Cassandra Robles Flores.Peer reviewe

Episode 8: In the Mud in Mexico

“We were of the mind that with studying the Deepwater Horizon in the northern Gulf we weren’t getting a full Gulf of Mexico perspective.” Geochemist David Hollander is travelling with an international team of scientists aboard a Mexican research vessel. Over the last few years, his team has studied the effects of the 2010 Deepwater Horizon spill. But today, they’re looking back at a spill that happened 35 years ago and what they learn on this trip might help them understand the future of the Gulf. Mind Open Media producer David Levin talks to David Hollander, Joel Ortega Ortiz, Isabel Romero, Adriana Gaytán-Caballero, and Travis Washburn about their experiences on the RV Justo Sierra in the southern Gulf of Mexico during the research on the Ixtoc spill

Episode 8: In the Mud in Mexico

“We were of the mind that with studying the Deepwater Horizon in the northern Gulf we weren’t getting a full Gulf of Mexico perspective.” Geochemist David Hollander is travelling with an international team of scientists aboard a Mexican research vessel. Over the last few years, his team has studied the effects of the 2010 Deepwater Horizon spill. But today, they’re looking back at a spill that happened 35 years ago and what they learn on this trip might help them understand the future of the Gulf. Mind Open Media producer David Levin talks to David Hollander, Joel Ortega Ortiz, Isabel Romero, Adriana Gaytán-Caballero, and Travis Washburn about their experiences on the RV Justo Sierra in the southern Gulf of Mexico during the research on the Ixtoc spill

Local ecological knowledge and perception of the causes, impacts and effects of Sargassum massive influxes: a binational approach

ABSTRACTCoastal communities of the Caribbean Sea and Gulf of Mexico have been affected by atypical influxes of pelagic macroalgae (Sargassum genus) since 2011, entailing ecological, economic and social impacts in need of characterization. We compiled and documented local ecological knowledge (LEK) and perceptions across diverse stakeholder groups from coastal communities in Mexico (Quintana Roo) (n=50 participants) and the United States (Florida) (n=36 participants) through on-site and online interviews and workshops undertaken from January to March of 2022, to understand how the knowledge of this phenomenon varies among communities and to characterize ecological and well-being impacts. Participants in Quintana Roo associated these influxes with both global phenomena (e.g., climate change) and local scale processes (e.g., currents/wind patterns) while Florida participants associated these events more with the latter. The communities in both regions perceived that the economy and the environment were the most impacted well-being categories. While influxes effects were mostly negative (80%) according to Quintana Roo participants (e.g., affected fisheries), Florida participants considered many positive effects of Sargassum (40%) on several well-being and ecological components (e.g., nursery habitat for marine species). In general, the perception of Sargassum as a problem was less pronounced in Florida, and these differences in perception are related to the magnitude of these influxes’ effect on the daily life of these communities. Overall, macroalgae management is still mainly focused on beach cleanup. Documenting LEK is important to delineate scientific research priorities and to provide decision makers with resources to develop efficient public policies and coastal management decisions

(Supplementary Table 1) Proportions of methane (C1) to ethane (C2) and the stable isotope composition of methane (δ¹³CCH4) of gas and oil collected by gas bubble sampler during METEOR cruise M114/2 in the southern Gulf of Mexico

Hydrocarbon seepage is a widespread process at the continental margins of the Gulf of Mexico. We used a multidisciplinary approach, including multibeam mapping and visual seafloor observations with different underwater vehicles to study the extent and character of complex hydrocarbon seepage in the Bay of Campeche, southern Gulf of Mexico. Our observations showed that seafloor asphalt deposits previously only known from the Chapopote Knoll also occur at numerous other knolls and ridges in water depths from 1230 to 3150 m. In particular the deeper sites (Chapopopte and Mictlan knolls) were characterized by asphalt deposits accompanied by extrusion of liquid oil in form of whips or sheets, and in some places (Tsanyao Yang, Mictlan, and Chapopote knolls) by gas emission and the presence of gas hydrates in addition. Molecular and stable carbon isotopic compositions of gaseous hydrocarbons suggest their primarily thermogenic origin. Relatively fresh asphalt structures were settled by chemosynthetic communities including bacterial mats and vestimentiferan tube worms, whereas older flows appeared largely inert and devoid of corals and anemones at the deep sites. The gas hydrates at Tsanyao Yang and Mictlan Knolls were covered by a 5-to-10 cm-thick reaction zone composed of authigenic carbonates, detritus, and microbial mats, and were densely colonized by 1-2 m-long tube worms, bivalves, snails, and shrimps. This study increased knowledge on the occurrences and dimensions of asphalt fields and associated gas hydrates at the Campeche Knolls. The extent of all discovered seepage structure areas indicates that emission of complex hydrocarbons is a widespread, thus important feature of the southern Gulf of Mexico