Cruise Objective: We will conduct research in exposed carbonate ecosystems on the Costa Rica margin (700-1,400 m), to test hypotheses about the influence of active seepage on carbonate rock animal communities and their successional phases, on microbial activity including anerobic methane oxidation and sulfide oxidation, on carbon isotopic composition of shelled organisms, and on phylogenetic affinities of animals. To test hypotheses we will sample existing authigenic carbonates from 3 levels of seepage activity: highly active, weak and inactive. Activity level will be defined by presence of /or proximity to bubbles/shimmering water, microbial mat development and megafauna, as well as previous fluid flow and composition measurements made at the Costa Rica study sites. We will sample 5 to 8 locations with each activity level in each study region, controlling for rock size and carbonate configuration when possible.
ALVIN: During 3 dives at each of 4 study sites we will conduct bottom surveys and video transects, measure S, T, O2, select 4 to 8 highly active, weakly active and inactive sites, photograph organisms and classify rocks in situ, collect rocks of varying sizes with organisms, and sample nearby sediments and biotic substrata (mussels, tube worms) for taxonomic comparisons. The remaining 2 dives at Costa Rica seeps will be used to conduct follow-up survey and sampling of the most promising locations, based on shipboard sample observations. Nighttime operations will consist of CTD casts (a minimum of one each at Mound 11, Mound 13, Jaco Scarp and Mound Quepos), multicoring (adjacent to mounds and at 400 m and 600 m sites in the OMZ), and pre-dive seabeam surveys.
Cruise information and original data are available from the NSF R2R data catalog.
Dataset | Brief Description |
---|---|
dive log - CROCKS-II | Alvin dive log from off Costa Rica January 2010 |
seep specimens | Methane seep hard substrate species collected on 4 RV/Atlantis cruises and lodged at the SIO Benthic Invertebrate Collection. |
seep stations | Station locations for CROCKS & HROCKS projects |
cruise tracks - CROCKS/HROCKS | cruise tracks for the CROCKS_II and HROCKS projects |
seep isotopes | C14 and N15 isotopes in rocks and animals from methane seep hard substrate ecosystems |
seep species abundance | species abundance on carbonate rocks collected from active and inactive sites at methane seeps on the Costa Rica and Oregon margins |
CTD Profiles | CTD station profile data |
16S rRNA gene and particulate monooxygenase diversity | 16S rRNA gene and particulate monooxygenase diversity |