The tubes of most serpulids are completely or partially cemented to the substrate. I especially love your 'pretty cool' piece which is a bryozoan with serpulid worm tubes growing on it. The carbonate rock samples from these two sites generally contained fewer serpulid tubes and much less authigenic aragonite cement than the Fossil Hill samples, with these cements forming thin veins within often siliciclastic-rich micrites. No complete worm tubes were found, however, the lack of diagenetic alteration of many of the Fossil Hill tube fragments enabled their morphology to be assessed in detail. doi: 10.1007/978-90-481-9572-5, Kiel, S., Sami, M., and Taviani, M. (2018). Intensity of fluid seepage is believed to vary with climatic conditions, in part because ocean warming or a lowering of pressure associated with sea-level changes can lead to dissociation of gas hydrate sequestered near the gas hydrate stability boundary (Kvenvolden, 1988; MacDonald et al., 2003; Buffett and Archer, 2004). Venus 51, 137–148. I would say that the serpulid could be fossilized (although I'm not sure at all). Neither gas bubbles or gas hydrates were observed during the ROV explorations. ten Hove, H. (1979). Fossil Code: CB045. Red munidopsid squat lobsters were common. 9:83. doi: 10.1038/s41467-017-02550-9, Warén, A., and Bouchet, P. (1993). The mound was hence termed “Fossil Hill.” In this study, results of extensive exploration of this enigmatic mound are presented with the aim to characterize the physical and biological features of this anomalous structure, as well as to ascertain its mode of formation, and whether this is associated with fluid seepage. Location County State/Province Directions,Notes Age Formation Fossils Comments Reference Lat-Long--MO: Along the Mississippi River from Cairo,IL to Baton Rouge,LA in loess (wind blown silt) deposits ranging from 9 to 23 meters in thickness and 50 to 100km in width (thicker in North and better developed on E side of river) Vinn, O. Written in stone: history of serpulid polychaetes through time. This second type of hard structure habitat, serpulid reef, was built by a colony or aggregate of tube-dwelling polychaete worms. This particular specimen is from Bromley in Kent, which is a classic locality. Faults can provide conduits for the migration of fluids and are known to be associated with cold seep communities (Zitter et al., 2008), and could additionally have provided serpulids with hard substrate in the form of MDAC for attachment. High-resolution mapping and sub-bottom profiling surveys of selected topographic features within the Santa Monica Basin region were conducted in March 2013 using an AUV equipped with 400 kHz Reson 7125 multibeam sonar, 110 kHz chirp sidescan sonar, and a 1–6 kHz sweep chirp subbottom profiler (see Caress et al. The editor and reviewers' affiliations are the latest provided on their Loop research profiles and may not reflect their situation at the time of review. doi: 10.1002/jqs.2819, Lojen, S., Cukrov, M., and Cukrov, N. (2014). The first (visited on ROV dive DR630) is a ∼5 m outcrop with >1 m of relief in 660 m water depth, located 290 m to the southeast of Fossil Hill on the flanks of the ridge (Figure 1C). I did some research and yes, he or she was correct. As serpulid tubes were observed along much of Fossil Hill’s extent of over 500 m by 250 m, this mound appears to host one of the largest known accumulations of fossil serpulids, greatly exceeding the dimensions of the Triassic-early Jurassic fossil serpulid reefs from southern Spain (Braga and Lopez-Lopez, 1989). Increasingly the ultrastructure of tubes is also used in relating fossil to recent taxa, in cases where the tube walls of fossil serpulids have not been significantly diagenetically altered (Vinn, 2005, 2008; Taylor and Vinn, 2006; Vinn et al., 2008a). 82, 206–212. Johnson, S. B., Krylova, E. M., Audzijonyte, A., Sahling, H., and Vrijenhoek, R. C. (2016). McLean, J. H. (1984). 154, 633–650. Serpula aggregates and their role in deep-sea coral communities in the southern Adriatic Sea. Only one half of the concretion is available. Multibeam bathymetric mapping of the Santa Monica Basin, southern California, has helped to reveal the existence of a number of elevated bathymetric features, or mounds, harboring cold seep communities (Normark et al., 2003; Hein et al., 2006). The worm is clearly visible and is about 4 cm in a concretion that is about 4.7 cm at its widest. During 2013–2014, mounds at ∼600 m water depth were observed for the first time and sampled by Monterey Bay Aquarium Research Institute’s ROV Doc Ricketts. Email This BlogThis! doi: 10.3354/meps132109, Olu, K., Sibuet, M., Harmegnies, F., Foucher, J., and Fiala-Medoni, A. doi: 10.1017/S0025315400023717, Hein, J. R., Normark, W. R., McIntyre, B. R., Lorenson, T. D., and Powell, C. L. II. Normark, W. R., Hein, J. R., Powell, C. L. I. I., Lorenson, T. D., Lee, H. J., and Edwards, B. D. (2003). Maybe try looking for signs of matrix inside the serpulid? Figure 3. London. Available at: http://chao.stat.nthu.edu.tw/wordpress/software_download/, Chiu, C. H., Wang, Y. T., Walther, B. A lot of time and skill has gone into preparing this so it is in relief from the matrix. Prog. Ippolitov, A., Vinn, O., Kupriyanova, E., and Jäger, M. (2014). So Fossil Hill was and continues to be an active cold seep. of 30–43 ka, most U-Th dates, as well as radiocarbon measurements on the above tubes and P. soyoae cluster at 16–25 cal ka BP (Tables 1, 2).