Deep Sea Biodiversity on the Continents, How It Happens?

*Andrés Castrillón*

### **Abstract**

Recent studies in the ocean depths have discovered a large number of organisms and microorganisms that live in extreme environments of hydrothermal vents and cold seeps obtaining their energy through anaerobic oxidation of methane (AOM) process through a microbial consortium capable of reducing sulfate and oxidizing methane simultaneously. On the surface, the fossil record of this type of chemosynthetic community has made it possible to establish the link between the tectonic plate dynamics with the origin of mineral deposits or sediments formed on the oceanic ridges and attached to the continents. The foregoing could be supported by the 13C and 18C stable isotopes analysis that has been carried out in the fossil record of rocks and sediments attached to the continents and the study of stable isotopes that is currently carried out in submersibles at mid-ocean ridges around the world. The relationship between current values and the fossil record is key to understanding, among others, the methane contribution to the environment and its variation throughout time. Cerro Matoso is a recent case that permitted linked the recent hydrothermal activity in the mid-ocean ridge, with those of the ancient ones.

**Keywords:** vent-cold seep, mid-ocean ridges, tectonic plates, vent communities, anaerobic methane oxidation

### **1. Introduction**

The evolution of the oceans is linked to the origin and geological evolution of the continents. The Plate Tectonics theory, which led to the understanding of the continental margin's evolution and the constant generation of oceanic crust of slow and ultra-slow spreading along different oceanic ridges, has been supported by the discovery and identification onshore of mantle and marine sedimentary rocks attached to the continents and exposed in impressive outcrops that show the impressive terrestrial dynamics.

As an example, one of the most important events in the geological record is related to the early Cambrian biological evolution, time during which the intracontinental extension was intensively dealing with hydrothermal activity in submarine settings [1] and black shale with multi-metal beds was formed and deposited around the world, are represented today with oceanic sediments attached to the continents and exposed on surfaces mainly in Asia and Europe. A series of hydrothermal vent community discovered at the Cambrian base in black shales indicated that

the hydrothermal vent existed in the extensive ecological community in the early Cambrian [2]. A lot of these early Cambrian vent communities are similar to the modern Eastern Pacific vent fauna. Therefore, the hydrothermal vent communities make up the main ecological community in the early Cambrian [2].

Recently, the studies of different hydrothermal systems that exist in the oceanic ridges (e.g., in Refs. [3–5]), enlightened the immense biodiversity around these environments where microorganisms live from the biosynthetic relationships that are generated with the organisms that hosted them. Studies of stable isotopes of 13C and 18O in the calcareous sediments at these mid-oceanic ridges and about the hydrothermal fluids that they host indicate that much of the carbon forming carbonates comes from the mantle and is generated from Fyscher–Tropsch reactions (FTT) (4H2 + CO2 - > CH4 + 2H2O), which is an abiotic process (e.g., Refs. [6, 7]).

Hydrothermal activity is a phenomenon that takes place all over the planet and refers to the circulation of fluids within the mantle and the hot Earth's crust. Manifestations of these processes that take place in the crust can be observed at the bottom of the sea (black or white smokers). The diversity of communities associated with hydrothermal vents in the mid-Atlantic oceanic ridge–MAR, has been described [8–10] and are considered exceptional in their biomass, distribution, and composition [10, 11].

### **2. Hydrothermal vent fauna discovery**

In 1977 the famous deep-sea submarine ALVIN, on the Ocean Pacific Ridge near the Galápagos Islands revealed incredible benthic communities of giant clams, tube worms, and microbial films that were associated with warm benthic fluids at temperatures over 370°C and emanation from black smokers [12]. That's how was discovered rich and unusual colonies that owed their existence to chemosynthetic microorganisms fed by magmatic degassing and water-rock reactions associated with the convection of warm waters along the Galápagos ridge [13], which confirmed the existence of active submarine hydrothermal systems windows and black smoker [14].

Constant investigations of the seabed have revealed that deep-sea hydrothermal windows harbor the most primitive sulfate-reducing, thermophilic, and chemosynthetic organisms that are implicated not only because of their biological adaptation in dark ocean-floor environments but also because they are related to the ancient forms of life on the planet [15–18].

The deep-sea hydrothermal systems expel large amounts of CO2 from the earth's mantle, the isotopic carbon footprint of the mantle is recorded in the sediments and calcareous shells of the organisms that live in these environments. Recent studies of the stable isotopes of 13C and 18C carried out in the waters and sediments in these settings have allowed us to recognize the geological record of sediments attached to the continents. The hydrothermal sediments hosted by the ultramafic rocks of Cerro Matoso, in Colombia northwestern, are an example of these processes and how the earth's dynamic systems seem to be similar today to that from the Jurassic or earlier in the oceanic ridges where rocks and sediments traveling through the ocean crust are in some occasions, attached to the continents in active tectonic plates regimes. According to Campbell [19], there are now at least 59 regional groupings of early Archean to Pleistocene age ore deposits and marine sedimentary sequences worldwide related to submarine origin.

Some examples are found on the Eurasian plates and the old continent. Fossils of early Cambrian hydrothermal vent communities in Guizhou Province, China, that

#### *Deep Sea Biodiversity on the Continents, How It Happens? DOI: http://dx.doi.org/10.5772/intechopen.110697*

might be the oldest hydrothermal vent community ever reported [2] or the hydrothermal vent worms from Cretaceous sulfide ore of the Samal Ophiolite, Oman [20] or the Silurian hydrothermal vent community from the southern Urals, Russia and Late Cretaceous hydrothermal vent communities from the Troodos ophiolite, Cyprus [21, 22] are indicative that the oceans are linked with the continents. Other examples are located in the American continent, where oceanic crust generated in the midoceanic Pacific ridge, is attached to the western part of the American continent along the oceanic trenches, when segments of oceanic crust instead of sinking under the continent, manage to ascend and attach themselves to it.

Now it is known that hydrocarbon vents and seeps are common at continental margins and oceanic spreading ridges worldwide, exuding fluids rich in CH4 and H2S, and teeming with life based on chemosynthesis. These settings have been implicated as the crucibles for life's origin, and as locals for methane release to the atmosphere from hydrate destabilization during the past climate change [19] According to Campbell, hydrothermal vents and seeps are necessary components of climate models, because cycling of methane-derived carbon from the lithosphere to the hydrosphere and atmosphere includes emissions from the 75,000 km-long oceanic ridge system, and from seepages or gas hydrates released around the world's continental margins (e.g., Refs. [23, 24]).

Extraordinarily around the world, in some places, these tectonic processes of collision between tectonic plates, allowed the rocks to preserve part of their geological record formed in the ridges, perhaps the deformation front or contact zone between the plates was far from these rocks enabling the hydrothermal or seep fauna preservation, denoting that the detachment and deformation zones did not affect them (**Figure 1**).

#### **Figure 1.**

*Distribution map of chemosynthesis-based settings, illustrating those Archean to recent hydrothermal vents and hydrocarbon seeps with associated metazoan and/or microbial signatures [19].*

### **3. Vents**

The first of these abiotic associations were recognized in the Cretaceous massive sulfide deposits in the sulfide ore of the Samal Ophiolites, Oman [20] since then they have been known to exist throughout the Phanerozoic [19]. One of the most recent microbial ecosystems was discovered along the Mid-Atlantic Ridge and transform faults where H2, CH4, and other elements are emitted from the deep sea in serpentinite outcrops [25]. Many vent communities are reported and studied today on the oceans deeps, although many of them have their ancestors in fossils of benthic communities, some findings will correspond to new species. The interaction between carbonates and tube worms is not yet known, it is possible that worms grow concomitantly, creating void and channels that favor the rise of hydrothermal fluids [26].

Additionally, the findings of fossilized hydrothermal vents communities allowed us to turn our regard to the oceans, and recognize their immense activity and diversity of ecosystems, so we can relate the fossil fauna of Cenozoic and some Mesozoic hydrocarbon seeps with those that exist today, which are dominated by mollusks; in contrast to the fauna that dominates seeps in most Mesozoic and Paleozoic deposits, which is dominated by brachiopods [27].

Currently, it has been possible to identify that hydrothermal benthic communities vary from the Mid-Pacific Oceanic Ridge to the Mid-Atlantic Ridge; the former is dominated in terms of biomass by a group of endemic taxa that form endosymbiotic relationships with chemosynthetic bacteria [22]. This group includes the vestimentiferan tube worm (=obturate pogonophoran), gastropods, mytilids (*Bathymodiolus* species), and vesicomid bivalves (*Calyptogena* species). Atlantic benthic communities are dominated by chemosymbiotic *Bathymodiolus* species and several species of Bresiliid shrimp (e.g., *Rimicaris exoculata*, in Ref. [28]), which can feed on exosymbiotic bacteria growing on their bodies [22]. Chemo-symbiotic taxa have important physiological and morphological adaptations to live in their habitats, an example being the loss or reduction of the alimentary tract in adults [22] or slower growth in related taxa at ocean depths [29, 30]. The habitat complexity leads to considerable amounts of heterogeneity in animal communities [30, 31]. An important aspect of modern benthic communities is the large number of endemic taxa that they possess so it is suggested that some endemic species represent Mesozoic and even Paleozoic remnants and that places of hydrothermal emanations acted as refuges to prevent their extinction [22].

Although it is unlikely that ancient hydrothermal deposits in the Archean oceanic crust are well preserved and both fossils and microfossils are easily identifiable, in Colombia, specifically at the Cerro Matoso nickel mine, a community of deep-sea benthic organisms is fossilized. This community hosted in a serpentinized rock attached to the South American continent during the Cretaceous, is forming bioherms where extremophile organisms could apparently survive under the influence of hydrothermal vents [32]. The history of the evolution of the biological communities associated with hydrothermal vents is little known, only 19 occurrences of fossils hosted in massive sulfide deposits have been found, all of them Phanerozoic in age: three from the Silurian in the benthic hydrothermal community south of the Urals Russian [21] six Devonian, one Jurassic, seven Cretaceous, one Late Cretaceous in the Trodoos Ophiolites on Cyprus [21] and one Eocene [22]. Few works have presented evidence of microbiological communities or microbial alterations in ophiolites and Archean greenstone belts [33].

### **4. Cold seeps**

A second type of chemosynthetic oasis, called cold seeps, was discovered during dives in the Gulf of Mexico and Pacific subduction zones depths [12] and related to hydrocarbon emissions, mainly methane but also ethane, propane and even oil [34] that seep through the sediment through cracks or fractures at flow velocities of a few tens of centimeters to a few meters per year [35], have been related to advection processes by the subduction of tectonic plates, due to processes of compaction and dehydration of hemipelagic sediments, a significant volume of water lost by sediments is expelled together with fluid mud and is channeled through deep faults until it is expelled on the ocean floor, where they manifest as mounds of mud with emanation windows often populated with benthic communities and covered by authigenic carbonates [26].

These cold seeps are associated with the dehydration of active and passive continental margins worldwide that generate favorable conditions for the precipitation of authigenic carbonates [26], which is mainly driven by the anaerobic oxidation of methane (AOM) through a microbial consortium capable of reducing sulfate and oxidizing methane simultaneously (e.g., in [36–41]).

Anaerobic microorganisms that mediate methane oxidation in AOM environments with sulfate, according to the equation CH4 + SO4 2 − → HCO3 - + HS− + H2O, carry out the dominant process in cold seep ecosystems and are one of the main methane consumers worldwide. Methane oxidation end products, such as bicarbonates and sulfides, are released into the surrounding rock or sediment and lead to the formation of authigenic carbonates that precipitate in sediments near the ocean floor at the bottom of a zone called the methane–sulfate interface (SMI) [26], which varies in depth depending on the rate of methane supply from the bottom and sulfate from above.

The precipitation of carbonates (high-magnesium calcite –HMC–, aragonite, or dolomite) close to the seafloor at cold seeps also results from anaerobic oxidation of methane (AOM), in which methane is oxidized using sulfate as an electron acceptor releasing bicarbonate and sulfide into pore-water [42].

Because oxygen is easily depleted below the ocean floor, subsurface anaerobes known as methanotrophs, hydrocarbon degraders, and sulfate-reducing bacteria, are the key functional groups in cold seep ecosystems [12]. The sulfur produced by these microorganisms can feed an entire ecosystem, microbial colonies, or faunas that can be found between 100 cm<sup>2</sup> and hundreds of square kilometers in diameter.

The relatively recent discovery of fossil fauna associated with seepage of hydrocarbons on the continents, both in Cenozoic rocks (e.g., in the western United States, Japan, and Italy) and Mesozoic (e.g., in the western United States, Japan, and France) and even Paleozoic records (e.g., in Germany, Morocco, and Mexico), have allowed us to understand the origin and types of mineralization of various formations. Additionally, the presence of ancient fauna of marine origin on the continents gives us signs and evidence of the Earth's dynamics.

Taxonomic groups have been reported from the Cretaceous to recent deposits associated with hydrothermal vents or cold seeps [21, 22, 43]. These groups include a variety of tubeworms, *Bathymodiolus* bivalves, and some bryozoans, among others. Members of the Bathymodiolina family occupy modern hydrocarbon seep and hydrothermal window environments [44]. Brachiopods are common in Paleozoic and Mesozoic seeps, infrequent in Cenozoic seeps, and almost absent in modern seeps and seeps [19]. Polychaetes of the order Eucidina are recognized as important members of Paleozoic marine benthic communities [45]. Modern seep communities

*Oceanography – Relationships of the Oceans with the Continents, Their Biodiversity...*


#### **Table 1.**

*Tubeworms occurrences in ancient hydrocarbon-seep deposits [27].*

are dominated by sibloginid tubeworms (Vestimentifera and Frenulata) as well as bivalves (Vesicomyidae, *Bathymodiolus*, Lucinidae, Thyasiridae and Solemyidae), all relying on endosymbiosis. Calcareous tubular fossils are uncommon in Phanerozoic seep deposits (**Table 1**) but have been tentatively identified as vestimentiferous.

Current knowledge of the microbial diversity around the vent-seep reveals that ε-proteobacteria is perhaps the key to the carbon, nitrogen, and sulfur cycle and have an important role in the symbiotic association with benthic metazoans [19]. Given that the Earth in its beginnings had a warmer environment, without atmospheric oxygen, rich in components such as CO2 and H2, perhaps life could flourish in warm environments very similar to today's hydrothermal systems, they may also represent analogies with ancestral niches of life and provide the basis for the interpretation of biomarkers of ancient hydrothermal systems [58]. If hydrothermal activity has continued through geological time, thermophilic communities have probably evolved to maintain themselves in these environments, leaving biomarkers in the rock and fossil record that, together with isotopes and minerals preserved in modern or ancient deposits, allow comparison of current organisms with ancient microbial communities and paleoenvironmental interpretations [58].

Cold seep sediments host a large proportion of sulfate-reducing bacterium and methane-oxidizing Archaea, mainly methanotrophic and thiotrophic species such as Euryarchaeota and Crenarchaeota, the former living in chemical symbiosis in clams and mussels, while the thiotrophic species live in tube worms [34]. Carbon isotope analyzes in seep ecosystems also have shown a close link between methane, archaeal methanotrophils, and their sulfate-reducing partners, precipitated authigenic carbonates, and higher trophic levels in the food web [59]. Thus, like hot seeps, cold seeps support an enormous free symbiotic microbial biomass that lives and thrives on the oxidation of methane, higher hydrocarbons, and sulfide [34, 60] that are hosted by the more fascinating organisms, such as tube worms, clams, crabs, and mussels, observed in these environments.

The nature of these ecosystems based on the microbial chemical synthesis of H2S seeps at high temperatures along mid-ocean ridges [61] presents an excellent analogy to anomalous fossil associations in the geological record of deep-sea marine environments commonly mineralized in base metals [62]. Ancient vent and seep deposits are also increasingly recognized and occur in various sizes, lithologies, biotic compositions, geotectonic settings, and ages.

### **5. Oceanic crust attached to the continents**

Around de world, there are various ophiolites exposed on the surface that have been targets of resources investigation because of their mineral content, but also because some of them contain fossil evidence of ancient vent communities. Examples are in the Northern Apennines where ophiolites are considered to have formed at various stages in the development of a mid-ocean ridge system in the Ligurian Tethys as the result of the divergence of the European and Adriatic plates in the Middle Jurassic (e.g., in [63]). In Morocco, the Aït Ahmane ultramafic unit of the ca. 760 Ma Bou Azzer ophiolite (Morocco) hosts a fossil black smoker-type hydrothermal system [64].

Ophiolites are formed because of the mid-ocean ridge generation that is driven by magmatic and tectonic processes, which result from seafloor spreading. Tectonically dominated spreading and the formation of detachment faults cause mantle rocks to be exposed to seawater (e.g., [65–68]). In the case of slow-spreading ridges (full spreading rate < ~5 cm/year), spreading is accommodated by the formation of a conjugated faults network that, in many places in the Atlantic Ocean, lift mantle peridotites up to the ocean floor (e.g., [6]). This phenomenon is referred to as tectonic accretion in opposition to magmatic accretion in the case of basaltic systems [6]. Ultramafic rocks may form domes associated to transform faults perpendicular to oceanic spreading ridges, where the detachment fault arrays produced thereby drag lower crustal magmatic chambers and triggered the emplacement of shallow-depth gabbro intrusions [67, 69–71]. This creates favorable conditions for the hydrothermal circulation systems in the serpentinite slab brought to the seafloor surface [69].

Some examples of how rocks from the mantle are exposed in mid-oceanic ridges comprise basaltic and gabbroic basement hosting high temperature (350–400 C) hydrothermal systems (e.g., in [70, 71]), however oceanic serpentinites exposed on the ocean floor in the MARK area [72] and at the 15,200 N fracture zone along the Mid-Atlantic Ridge [73] or the peridotite-hosted system at the Atlantis Massif along the Mid-Atlantic Ridge [74] has shown that hydrothermal systems can vary from cold to high temperatures.

It is proposed that the breaking-up of the oceanic plates in heterogeneous crust fragments does not produce vertical planes, but instead deep and slightly inclined faults appear to control most of the slow movement of the plate, thus exhuming and exposing lower crust and mantle rocks [75]. Some of these rocks are exposed as oceanic core complexes (OCC), which are deep sections of the oceanic lithosphere exhumed to the seafloor by long-lived detachment faults formed along with slow and ultra-slow spreading centers at different scales [67, 76–78]. The OCC are formed perpendicular to the ridges near the end of the slow spreading segments, although their evolution could suggest that fracture zones do not become locked immediately on transform-to-fracture transition [67]. The domes can exceed 100 m of relief high, several hundred meters in width, and up to kilometers in length [75] conditions that could be compared with the case of Cerro Matoso peridotites located northwest of Colombia in the Caribbean region.

Precisely, the most recently studied example that allows establishing the relationships between the oceans and continents, their biodiversity, and the atmosphere, is in Cerro Matoso, where peridotite as part of ophiolitic segments was attached to Western Colombia controlled by complex geometries at the time of the collision between the Caribbean-, Nazca-, Cocos- and South American Plates.

The oceanic crust that builds today in the Central Caribbean region is Cerro Matoso, which was formed during the Cretaceous, about 89 Ma ago [79]. The thick oceanic crust of the Caribbean plate appears to be the tectonized remnant of an eastern Pacific oceanic plateau that has been inserted between North and South America. The emplacement of the plateau into its present position has resulted in the abduction and exposure of its margins, providing an opportunity to study the age relations, internal structure, and compositional features of the plateau.

The synchronicity of ages across the region is consistent with a flood basalt origin for the bulk of the Caribbean plateau (i.e., large volume, rapidly erupted, and regionally extensive volcanism in the Pacific Ocean), far west of its present position [80, 81]. As the American continent was moving to the west during the Late Cretaceous and the oceanic plate in turn was moving eastwards, oceanic segments were accreted in the western part of the continent [82]. Aspects of the collision and subduction or accretion in which the geometry of the process prevents an ophiolite segment from entering the subduction zone and instead preserves it against continental crust at shallow levels were discussed by Ref. [82].

In the Southern Caribbean, oblique convergence also resulted in the accretion of peridotites with high-pressure associations that may have started from the Eocene (55–50 Ma) and completed in the Oligocene or even in the early Miocene (30–15 Ma ago) [82]. These high-pressure associations correspond with bodies accreted to the western edge of the South American Plate during the Eocene [83].

### **6. Stable isotopes**

Carbon and oxygen stable isotopes in vents and seep-carbonates are biogeochemical archives of past fluid activity and composition, and their measured values in the fossil content or substrate sign the geological history of these deposits (e.g., in Ref. [19]). The classic, isotopically depleted, carbonate-carbon signals recorded in some seep deposits and hydrothermal vents, were derived from microbially mediated, anaerobic oxidation of methane (AOM) in the sulfate reduction zone (e.g., in Refs. [19, 26]). However, variation in both carbonate-carbon and oxygen values is dictated by several processes, including kinetic isotope fractionation, hydrate dissociation, variable mixing of carbon sources, tapping of deep burial fluids (via faults or erosion), clay mineral dehydration, and diagenesis (e.g., in Refs. [19, 26]). Biogeochemical conditions in cold seep systems as well as in deep-sea hydrothermal systems depend on the flux of methane, availability of sulfate, temperature, and redox conditions. These conditions promote the development of chemosynthetic communities mainly dependent on methane and/or sulfur, driving microbial reactions that alter sulfur and carbon pools and whose pathways involve the formation of authigenic minerals (e.g., in Ref. [4, 5]).

Oxygen isotope analyses of marine carbonate fossils could substantiate the modeled paleoclimatic evolution by providing information on oceanic paleoclimatic temperatures [84], while carbon isotopes can be used to document changes in δ 13C values of ancient oceanic dissolved inorganic carbon (DIC). In this sense, stable isotope and

#### *Deep Sea Biodiversity on the Continents, How It Happens? DOI: http://dx.doi.org/10.5772/intechopen.110697*

element composition of the sediments and rocks are used to reconstruct the origin and nature of the fluids from which they formed (e.g., in Ref. [19]). However, isotope ratios of coeval carbonate shells of various organisms may differ from one another and only a study of a well-preserved fossil shell assembly could provide clear information on temperature variations within the water column. Nonetheless, bulk sample isotope analysis also gives good information about the conditions under there were formed.

Different approaches can be used to characterize the nature, source, and evolution of fluids benthic by examining the mineralogy, petrography, and isotopic characteristics of the carbonates [26]. Considering the link between hydrothermal vents, hydrocarbon-rich cold seeps, gas hydrate formation, and sub-seafloor hydrocarbon reservoirs (e.g., in Ref. [85]), the understanding of the occurrence of authigenic mineralization is crucial for linking the geological record of the rocks.

As the hydrothermal vents hosted by ultramafic rocks have been recently studied (e.g., in Refs. [4, 25]), the source of fluid hosted by them has been related to the serpentinization process that suffers peridotites when they are under intense activity provided by the heat of intrusion of mafic magmas or by the cooling of the ultramafic lithosphere, the later results in a fluid circulation that is driven by convectiondissipated heat from the bottom and exothermic chemical reactions between the circulating fluids and host [73]. Serpentinite-derived fluids in both deep-sea and ophiolite environments, where methane has been measured, present negative δ13C values, including −11.9‰ at Lost City, −10.3‰ at Logatchev, −16.7‰ at Rainbow, −18‰ at Elba, and − 7.7‰ in the Zambales ophiolite [86–92]. Hydrothermal systems hosted in ultramafic rocks are present in Logatchev, Rainbow, and Lost City Hydrothermal Field-LCHF [3]. High-temperature black smokers generated by the cooling of different mixtures of gabbro and deep ultramafic materials are usual in these environments [3].

Some hydrothermal fields with associated calcareous sediments (Lost City and Rainbow) have been especially well studied [4, 88, 93–95]. In the "Clamstone" site on Rainbow Hill, the carbon isotopic composition of Thyaira aff. Southern shells showed signatures of more depleted 13C (δ 13C = − 7.69 ± 1.60‰) than expected, which is interpreted by the authors as a contribution of oxidized methane in the pore-water filling of the burrows formed by bivalves [96]. The formation of these sedimentary structures is analogous to fluid-induced chimney formation on modern vents. A record of these environmental conditions and isotopic signatures is in Cerro Matoso.

### **7. Cerro Matoso case**

Cerro Matoso is an open-Pit mine, which is mined, molten, and produced a Fe-Ni allay from the laterites formed as a product of the peridotites weathering. Locally, on the peridotites, a community of benthic organisms that originated in the ocean depths is fossilized. The community is hosted in sediments overlaying the peridotites and is forming bioherms, where extremophile organisms could survive under the influence of hydrothermal emanation vents. Two types of sediments identified as green fossiliferous claystone and black mudstone contain evidence of having been generated under the influence of hydrothermal activity at intermediate temperatures [97]. The 18O and 13C isotopic reactions of both types of sediments (i.e., claystone and mudstone), analyzed in bulk sediments are consistent with those observed in serpentinization settings of ultramafic rocks (e.g., in Refs. [62, 92, 98]).

The mineral precipitation temperatures of the green fossiliferous claystone, obtained through the [99] relationship of the δ 18O values are in the range of 30 to 80°C, and although the lowest values could be interpreted as surface temperatures considering meteoric water, which is supported by the relatively negative δ 13C values, the δ 18O values indicating temperatures close to 80°C are signing a hydrothermal input. The precipitation temperatures of the black mudstone in a wider range of δ 18O values (15.9 to 29.8‰ V-SMOW) are better explained by the influence of low temperature hydrothermal/diagenetic system, however, the values of δ 18O (25.1 to 29.8‰ SMOW) reported in the intraclast within black mudstone are signing higher temperatures that only can be justified if fluids are enriched in 18O (magmatic, metamorphic or diagenetic water). The corresponding lower δ 13C values (in intracalst, −27‰ V-PDB) could only be explained by these processes or by the oxidation of methane related to these systems. Contrary to the Cerro Matoso evidence, other smectites produced by ultramafic weathering [100] with δ 18O values (20.3 to 24.3‰ SMOW), in the nickel smectites in Murrin Murrin, Western Australia, represent isotopic δ 18O values that correlate with water-rock interactions at low temperatures due to the contact of meteoric fluids during mineral leaching processes in which laterites are formed [101].

Marine/diagenetic waters with relatively negative values of Dissolved Inorganic Carbon (DIC) are formed by the biological degradation of organic matter in closed systems [102], however, there is no obvious source of significant organic material (e.g., carbon-rich shales) in the sedimentary succession hosting the Cerro Matoso peridotites, so the production of abiogenic methane by serpentinization of peridotite looks like the more possible light δ 13C source. Methane in modern serpentinite-derived fluids in both the deep-sea and in ophiolite environments has negative δ 13C values (e.g., −11.9‰ at Lost City, −10.3‰ at Logatchev, −16.7‰ at Rainbow, −18‰ at Elba and − 7.7‰ in the Zambales ophiolite) similar to those reported in Cerro Matoso. Some of this methane will be oxidized close to the seafloor to produce 13C-depleted DIC, and the high pH and Ca concentrations in the serpentinite-derived fluids promote carbonate and mineral precipitation on mixing with seawater [103, 104].

The fluids generated during the peridotite serpentinization favored the calcareous sedimentary succession formations found on top of the crystalline rocks of Cerro Matoso when the mantle rocks were exposed in an ancient mid-oceanic ridge. The δ13C values between −27.1 and − 17.1‰ (i.e., calcareous intraclast within the black mudstone), indicating a low contribution of marine DIC surely associated with anaerobic oxidation of methane process–AOM, is interpreted as a contribution of oxidized methane in the pore-water filling the burrows formed by the bivalves (e.g., Ref. [90]). The Cerro Matoso 13C-isotope data are in the range of serpentinite samples of six different regions in the Mid-Atlantic Ridges (MAR) and yielded δ13C values ranging from −29 to −4‰ [5], which sign methane sources. Owing to the very low concentration of inorganic carbon in serpentinization fluids, the most feasible origin for this 13C depletion is the oxidation of methane [105]. The rare rock fragments characterized by altered ultramafic lithoclasts (serpentinites) and claystone are in part similar to those described in Saldanha sediments, a hydrothermal site of the MAR partly supported by serpentinization processes [106].

Additionally, the δ13C values in Cerro Matoso agree in part with the values of δ 13C of CH4 and CO2 of high- and low-temperature hydrothermal fluids, at 9° 50'N East Pacific Rise, with an average value of δ13C of −30.2 ± 2.7‰ and − 4.5 ± 0.53‰, respectively, which are somewhat more diminished than the average values of δ13C in high-temperature vents, −20.1 ± 1.2‰ of CH4 and − 4.08 ± 0.16‰ of CO2 [89]. These values are among the lightest measured in hydrothermal vents

*Deep Sea Biodiversity on the Continents, How It Happens? DOI: http://dx.doi.org/10.5772/intechopen.110697*

[30, 87, 107, 108]. In general, carbon dioxide derived from magmatic degassing, which retains values of δ 13C, mainly between −4 and − 8‰ [109], and carbonates in the mantle, between −5 and − 7‰ [110, 111], will be related only to the most negative δ13C isotopic signature of the marine sediments in Cerro Matoso because in general, all samples present a wide range of δ13C. The more negative δ13C values point out the presence of methane oxidation events, favoring the growth of carbonates in the sediments overlaying the ultramafic rocks. Similar conditions have been reported around deep marine hydrothermal vents [5, 25, 92].

The initial isotopic carbon ratio of the carbon dioxide discharged from geothermal and ultramafic systems in oceanic ridges, which ranges from −8‰ to −3‰, plus the maximum fractionation factor resulting from the oxidation of anaerobic or aerobic methane (1.039) at hydrothermal environments around ultramafic rocks [89, 112] favoring depletion by at least −13‰ of the original isotope signature, giving δ 13C values around −21‰ that are consistent with the negative isotopic signature of the minerals forming marine claystone and mudstone in Cerro Matoso. These values may also record anaerobic oxidation of methane or bacterial oxidation/sulfate-reduction [102].

Evidence that methane emissions from mid-ocean ridges have persisted since their origin, and that their influence can be analyzed from the fossil record in rocks originating from mid-ocean ridges, but that today are attached to the continents, may be verified from the study of the isotopic fractionation models for 13C and 18O (e.g., in Ref. [113]). These models allow us to compare the expected behavior of the fraction that reacts in the process of gain and loss of heavy and light isotopes, in an open system in the presence of methane and sulfur, such as the one that occurs in the mid-oceanic ridges (e.g., Ciudad Lost, Logatchev). In the case of Cerro Matoso, a hydrothermal system has been considered, similar to the recently studied Lost City hydrothermal field, on the Mid-Atlantic oceanic ridge, where ultramafic rocks are exposed on the seabed and host chemosynthetic communities and hydrothermal vents that manage to resemble what was observed in the outcrops of the open-pit nickel mine of Cerro Matoso. However, the results reflect the existing pre-Cretaceous conditions in the ancient mid-oceanic Pacific ridge, where the Cerro Matoso peridotites must have been exhumed hosting hydrothermal systems that allowed the vent communities to be hosted on the rocks and marine sediments.

For the isotopic modeling of 13C in the Cerro Matoso green fossiliferous sediments (**Table 2**), an environment of warm waters in the ocean depths was considered, in which H2S forms a group of isotopes together with CH4, OH− , HCO3 − and Fe, among other elements, and where CaCO3 and CH4 are products of the isotopic exchange during the process of loss and gain of electrons. In this environment, the fractionation factor resulting from anaerobic or aerobic oxidation of methane can be as high as 1.039 [89, 112, 114]. Based on this value, and assuming that there was an anaerobic methane oxidation process, the 13C fractionation model considers the maximum value of isotopic fractionation ∆ = 39‰, for product 1 or CaCO3. The residual substrate in these reactions, in our case, the product 2 or (CH4), assumes an isotopic fractionation ∆ = 12.3‰, values that are in agreement with the laboratory results of δ13C, and represent the highest isotopic depletion in the seawater. Maintaining the mass balance, the model made (**Figure 2**) shows the behavior of the expected isotopic variations (solid lines red and blue), for products 1 and 2, and the variations that would occur in the internal pool of isotopes (dotted line in red), in relation to the isotope fraction, which reacts for each element within the system.

Within this model, under the same established conditions and considering an equilibrium constant KIE = −32, the results of the black mudstone (**Table 3**) also were


#### **Table 2.**

*Fractionation factors (bold) for CH4 and CaCO3 for green fossiliferous claystone.*

#### **Figure 2.**

*Fractionation in an open system of Cerro Matoso hydrothermal sediments (green fossiliferous claystone), with exact equations for fractionation in the residual substrate (top line) and product (blue line f = 1-(δ 13C ‰/−32). Green dotes when* ∆*1 = 39‰, y* ∆*2 = 12.3‰.*

plotted (**Figure 3**). The δ 13C in V-PDB of the full 27 samples analyzed from Cerro Matoso (blue boxes) are represented in both figures. As a result, the δ13C values from Cerro Matoso coincide with the 13C isotope values expected for the precipitation of CaCO3 or product 1 (solid line) according to the model.

*Deep Sea Biodiversity on the Continents, How It Happens? DOI: http://dx.doi.org/10.5772/intechopen.110697*


#### **Table 3.**

*Fractionation factors (bold) for CH4 and CaCO3 for black mudstone succession.*

#### **Figure 3.**

*Fractionation in an open system of Cerro Matoso metalliferous sediments (black mudstone succession), with exact equations for fractionation in the residual substrate (top line) and product (blue line f = 1-(δ 13C ‰/−32). Green dotes when* ∆*1 = 39‰, y* ∆*2 = 12.3‰.*

The variations in time during the isotopic fractionation process can be analyzed in detail, on a medium or large scale. In the Cerro Matoso stratigraphic succession, this variation during mineral precipitation can be observed in the record of carbonates

present in the samples. Considering the location of each sample in-depth, the formation time can be related to the hydrothermal activity. In principle, the data indicate that there was an approximate average enrichment in δ 13C of 20‰, in the first part of the succession, which is proposed as a stage for the formation of clay minerals. The samples of higher levels in the stratigraphic succession in the mounds, with averages δ13C = −10‰, suggest a 5 to 7‰ depletion of δ13C in these rocks, a decrease that can occur in sediments located further from the vents or when a decrease in the intensity of these is represented (variations in contributions of CO2 or CH4).

The δ13 C values between (i.e., −24 to −16.9‰ in basal fissured and breccia mudstones - fb-M), suggest that the main carbon source is methane while the δ 13C ranges between (−14.4 to −10.1‰) and (−8.5 to −1.5‰) in the green fossiliferous claystone indicate episodes of dissolved inorganic carbon input— DIC that are mixed with methane sources. For their part, the carbonates that form the biostructures and concretions within the green fossiliferous claystone, with δ13C values between (−9.4 to −6.2‰) and (−11.7 to −11.2‰), also suggest contributions of DIC and methane during their training.

Due to the fact that today the only carbonate present in the samples is siderite, it is possible to assume, according to the 13C and 18O isotope composition that siderite (diagenetic origin) replaced the primary fossils carbonate in the claystone, inheriting the isotopic composition of the precursor. This is considering the minimal difference (= 0.00042) in the fractionation factor between aragonite (∆ = 1.00856) and siderite (∆ = 1.00898) at 75°C [115], which indicates that the temperatures recorded by the δ 18O, are quite consistent with the estimates of the initial fluid–rock interaction, in the hydrothermal system suggested for Cerro Matoso. Everything suggests that the siderite is formed in the process of early diagenesis in which, due to fluid–rock interaction on the seabed, Fe replaces Ca in the carbonate structure, so that the CO3 ion preserves the isotopic footprint of the hydrothermal environment where the benthic community settled.

Accordingly, if the original authigenic carbonates inherited the δ13C from the characteristic values of their specific carbon sources (+/− with DIC mixture), their δ13C signature indicates the existence of microbial processes, which are characteristic in vent-related carbonate deposits [116]. Thus, the isotopic signature was preserved during the diagenetic processes and later during the supergene processes suffered by the Cerro Matoso sediments, the former, favored by the low temperatures of the ̈diffuse ̈ fluids and the minimal variation in the fractionation factor between aragonite and siderite.

Owing to the isotopic fingerprinting of minerals formed under submarine conditions and the study of current hydrothermal systems, both the mid-oceanic ridge of the Atlantic and the mid-oceanic Pacific ridge, was possible to reconstruct the geological history of Cerro Matoso, and other deposits in ophiolites worldwide (e.g., sulfide ore of the Samal Ophiolite, Troodos ophiolite of Cyprus), suggesting that serpentinization-derived fluids flow are active for a considerable time during the formation of the mounds and tabular units, as well as, that the ocean is intimately related to the continents and that methane produced in active ancient ocean ridges appear to be similar to the methane produced in the actual mid-ocean ridge configuration.

Finally, many vent communities found on continents today must have their ancestors in ancient vent communities. In this sense, Kiel S [117] suggests that the fauna found today may, due to its exceptional level of endemism in a high taxonomic range, suggest a long and continuous evolutionary history that would extend from the Paleozoic in some parts of the world, where they have been reported.

*Deep Sea Biodiversity on the Continents, How It Happens? DOI: http://dx.doi.org/10.5772/intechopen.110697*

## **Author details**

Andrés Castrillón Universidad Nacional de Colombia, Bogotá

\*Address all correspondence to: acastrillonp@unal.edu.co

© 2023 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

## **References**

[1] Yu BS, Chen JQ, Li XW, et al. The geochemistry of Lower Cambrian black shales and its relation to crustal evolution in the Tarim Basin. Science China (Ser D). 2002;**32**:374-382 [in Chinese]

[2] Yang R, Wei H, Bao M, Wang W, Wang Q, Zhang X, et al. Discovery of hydrothermal venting community at the base of Cambrian barite in Guizhou Province, Western China: Implication for the Cambrian biological explosion. Progress in Natural Science. 2008;**18**:65- 70. DOI: 10.1016/j.pnsc.2007.07.006

[3] Kelley D, Shank T. Hydrothermal systems: A decade of discovery. In: Slow Spreading Environments in Diversity of Hydrothermal Systems on Slow Spreading Ocean Ridges. Geophysical Monograph Series. Washington, USA. Vol. 188. 2010. pp. 369-407

[4] Früh-Green GL, Kelley DS, Bernasconi SM, Karson JA, Ludwig KA, Butterfield DA, et al. 30,000 years of hydrothermal activity at the lost City vent field. Science Reports. 2003;**301**:495-498. Available from:http:// science.sciencemag.org/

[5] Früh-Green GL, Connelly JA, Plas A, Kelley DS, Grobéty B. Serpentinization of oceanic peridotites: Implications for geochemical cycles and biological activity. In: The Subseafloor Biosphere at Mid-Ocean Ridges. Washington, D.C: American Geophysical Union; 2004

[6] Konn C. Origin of Organic Compounds in Fluids from Ultramafic Hosted Hydrothermal Vents of the Mid-Atlantic Ridge. Stockholm: Meddelanden från Stockholms Universitets Intitution för Geologi och Geokemi. 2009

[7] Hoefs J. Stable Isotope Geochemistry. Berlin: Springer-Verlag; 2015. p. 389

[8] Van Dover CL. Biogeography of hydrothermal vent communities along seafloor spreading centers. Trends in Ecology & Evolution. 1990;**5**:242-246

[9] Gebruk AV, Chevaldonne P, Shank T, Lutz RA, Vrijenhoek RC. Deepsea hydrothermal vent communities of the Logatchev area (14°45'N, mid-Atlantic ridge): Diverse biotopes and high biomass. Journal of the Marine Biological Association of the UK. 2000;**80**:383-393

[10] Desbruyères D, Almeida A, Biscoito M, Comtet T, Khripounoff A, Le Bris N, et al. A review of the distribution of hydrothermal vent communities along the northern Mid-Atlantic Ridge: Dispersal vs. environmental controls. Hydrobiology. 2000;**440**:201-216

[11] Hessler RR, Smithey WM. The distribution and community structure of megafauna at the Galapagos Rift hydrothermal vents. In: Rona PA et al., editors. Hydrothermal Processes at Seafloor Spreading Centers. New York: Plenum; 1983. pp. 735-770

[12] Jorgensen BB, Boetius A. Feast and famine — Microbial life in the deep-sea bed. Focus on Marine Microbiology. 2007;**5**:770-781

[13] Delaney JR, Kelley DS, Lilley MD, Butterfield DA, Baross JA, Wilcock WSD, et al. The quantum event of oceanic crustal accretion: Impact of diking at Mid-Oceanic Ridges. Chemistry and Biology of the Oceans Science. 1998;**281**:222-230

[14] Heikinian R, editor. Petrology of the Ocean Floor. Elsevier Oceanography Series. New York: Elsevier scientific publishing company; 1982. p. 393

[15] Jannasch HW. The chemosynthetic support of life and the microbial

*Deep Sea Biodiversity on the Continents, How It Happens? DOI: http://dx.doi.org/10.5772/intechopen.110697*

diversity at deep-sea hydrothermal vents. Proceeding of the Royal Society of London Biological Science. 1985;**225**:277-297

[16] Travis J. Probing de unsolved mysteries of the deep. Science. 1993;**259**:1123-1124

[17] Farmer JD. Hydrothermal systems: Doorways of the early biosphere evolution. GSA Today. 2000;**10**:1-9

[18] Davies P. The origin of the life I: When and where did it begin? Scientific Progress. 2001;**84**:1-16

[19] Campbell KA. Hydrocarbon seep and hydrothermal vent paleoenvironments and paleontology: Past developments and future research directions. Palaeogeography Palaeoclimatology Palaeoecology. 2006;**232**(2-4):362-407

[20] Haymon RM, Koski RA, Sinclair C. Fossils of hydrothermal vent worms from Cretaceous sulfide ores of the Samail ophiolite, Oman. Science. 1984;**223**:1407-1409

[21] Little CTS, Herrington RJ, Maslennikov VV, Morris NJ, Zaykov VV. Silurian hydrothermal-vent community from the southern Urals, Russia. Nature. 1997;**385**:146-148

[22] Little CTS, Can JR, Herrington RJ, Morisseau M. Late Cretaceous hydrothermal vent communities from the Troodos ophiolite, Cyprus. Geology. 1999;**27**:1027-1030

[23] Hovland JAG. Seabed Pockmarks and Seepages: Impact on Geology, Biology and the Marine Environment. London: Graham and Trotman; 1988. pp. 1-293

[24] Judd AG. The global importance and context of methane escape from the seabed. Geo-Marine Letters. 2003;**23**:147-154

[25] Kelley DS, Karson JA, Blackman DK, Früh-Green GL, Butterfield DA,

Lilley MD, et al. AT3-60 shipboard party, an off-axis hydrothermal vent field near the Mid- Atlantic ridge at 308N. Nature. 2001;**412**:145-148

[26] Han X, Suess E, Sahling H, Wallman K. Fluid venting activity on the Costa Rica margin: New results from authigenic carbonates. International Journal of Earth Sciences. 2004;**93**:596-611

[27] Peckmann J, Little CTS, Gill F, Reitner J. Worm tube fossils from the Hollard Mound hydrocarbon-seep deposit, Middle Devonian, Morocco: Palaeozoic seep-related vestimentiferans? Palaeogeography Palaeoclimatology Palaeoecology. 2005;**227**:242-257

[28] Williams AB, Rona PA. Two new caridean shrimps (Bresilidae) from hydrothermal field on the Mid-Atlantic Ridge. Journal of Crustacean Biology. 1986;**6**:446-462

[29] Lutz RA, Kennish MJ. Ecology of deep-sea hydrothermal vent communities: A review. Reviews of Geophysics. 1993;**31**:211-242

[30] Shank TM, Fornarik DJ, Von Damm KL, Lilley MD, Haymon RM, Lutz RA. Temporal and spatial patterns of biological community development at nascent deep-sea hydrothermal vents (98N, East Pacific Rise). Deep Sea Research. 1998;**45**:465-516

[31] Tunnicliffe V, Juniper SK. Dynamic character of the hydrothermal vent habitat and the nature of the sulfide chimney fauna. Progress in Oceanography. 1990;**24**:1-14

[32] Castrillón A. Carbonatos y otros minerales autigénicos asociados a las lateritas niquelíferas de Cerro Matoso y su posible relación con actividad hidrotermal y reducción de sulfatos [Ph.D thesis]. Bogotá: Universidad Nacional de

Colombia; 2019. Available from: https:// repositorio.unal.edu.co/handle/unal/79059

[33] Banerjee NR, Simonetti A, Furnes H, Muehlenbachs K, Staudigel H, Heaman L, et al. Geology. 2007;**35**:487

[34] Fisher C, Roberts H, Cordes E, Bernard B. Cold seeps and associated communities of the Gulf of Mexico. Oceanography. 2007;**20**(4)

[35] Niemann H, Lösekann T, de Beer D, Elvert M, Nadalig T, Knittel K, et al. Novel microbial communities of the Haakon Mosby mud volcano and their role as methane sink. Nature. 2006;**443**(7113):854-858

[36] Kulm LD, Suess E, Moore JC, Carson B, Lewis BT, Ritger SD, et al. Oregon subduction zone: Venting, fauna and carbonates. Science. 1986;**231**:561-566

[37] Bohrmann G, Greinert J, Suess E, Torres M. Authigenic carbonates from the Cascadia subduction zone and their relation to gas hydrate stability. Geology. 1998;**26**(7):647-650

[38] Boetius A, Ravenschlag K, Schubert CJ, Rickert D, Widdel F, Gieseke A, et al. A marine microbial consortium apparently mediating anaerobic oxidation of methane. Nature. 2000;**407**:623-626

[39] Peckmann J, Gischler E, Oschmann W, Reitner J. An Early Carboniferous seep community and hydrocarbon-derived carbonates from the Harz Mountains, Germany. Geology. 2001;**29**:271-274

[40] Suess E. Gashydrat—Eine Verbindung aus Methan und Wasser. Nova Acta Leopoldina NF. 2002a;**85**(323):123-146

[41] Suess E. The evolution of an idea: From avoiding gas hydrates to actively drilling for them. In: Achievements and opportunities of scientific ocean drilling. The legacy of the Ocean Drilling Program. JOIDES Journal. 2002b;**28**(1):45-50

[42] Núñez-Useche F, Canet C, Liebetraud V, Pi Puig T, Poncianoe AC, Alfonso P, et al. Redox conditions and authigenic mineralization related to cold seeps in Central Guaymas Basin, Gulf of California. Marine and Petroleum Geology. 2018;**95**:1-15. DOI: 10.1016/j. marpetgeo.2018.04.010

[43] Campbell KA, Francis DA, Collins M, Gregory MR, Nelson CS, Greinert J, et al. Hydrocarbon seep-carbonates of a Miocene forearc (East Coast Basin), North Island, New Zealand. Sedimentary Geology. 2008;**204**:83-105

[44] Van Dover CL. The Ecology of Deep-Sea Hydrothermal Vents. New Jersey: Princeton University; 2000. p. 424

[45] Suttner TJ, Hint O. Devonian scolecodonts from the Tyrnaueralm, Graz Palaeozoic, Austria. Memoirs of the Association of Australasian Palaeontologists. 2010;**39**:139-145

[46] Dubé TE. Tectonic significance of Upper Devonian igneous rocks and bedded barite, Roberts Mountains allochthon, Nevada, U.S.A. In: McMillan NJ, Embry AF, Glass DJ, editors. Devonian of the World (Volume II, Sedimentation), Canadian Society of Petroleum Geologists Memoir; 1988;**14**:235-249

[47] Von Bitter P, Scott SD, Schenk PE. Early Carboniferous low-temperature hydrothermal vent communities from New-foundland. Nature. 1990;**344**:145-148

[48] Gómez-Pérez I. An Early Jurassic deep-water stromatolitic bioherm related to possible methane seepage (Los *Deep Sea Biodiversity on the Continents, How It Happens? DOI: http://dx.doi.org/10.5772/intechopen.110697*

Molles Formation Neuque ́n, Argentina). Palaeogeography, Palaeoclimatology, Palaeoecology. 2003;**201**:21-49

[49] Campbell KA, Farmer JD, Des Marais D. Ancient hydrocarbon seeps from the Mesozoic convergent margin of California: carbonate geochemistry, fluids and palaeoenvironments. Geofluids. 2002;**2**:63-94

[50] Hikida Y, Suzuki S, Togo Y, Ijiri A. An exceptionally well-preserved seep community from the Cretaceous Yezo fore-arc basin in Hokkaido, northern Japan. Palaeontological Research. 2003;**7**:329-432

[51] Schwartz H, Sample J, Weberling KD, Minisini D, Moore JC. An ancient linked fluid migration system: cold-seep deposits and sandstone intrusions in the Panoche Hills, California, USA. Geo-Marine Letters. 2003;**23**:340-350

[52] Goedert JL, Squires RL. Eocene deepsea communities in localized limestones formed by subduction-related methane seeps, southwestern Washington. Geology. 1990;**18**:1182-1185

[53] Goedert JL, Thiel V, Schmale O, Rau WW, Michaelis W, Peckmann J. The Late Eocene ¨Whiskey Creek methaneseep deposit (western Washington State)—Part I: geology, palaeontology, and molecular geobiology. Facies. 2003;**48**:223-240

[54] Goedert JL, Campbell KA. An early Oligocene chemosynthetic community from the Makah Formation, northwestern Olympic Peninsula, Washington. Veliger. 1995;**38**:22-29

[55] Goedert JL, Peckmann J, Reitner J. Worm tubes in an allochthonous coldseep carbonate from Lower Oligocene rocks of western Washington. Journal of Paleontology. 2000;**74**:992-999

[56] Naganuma T, Okayama Y, Hattori M, Kanie Y. Fossil worm tubes from the presumed cold-seep carbonates of the Miocene Hayama Group, central Miura Peninsula, Japan. The Island Arc. 1995;**4**:199-208

[57] Peckmann J, Thiel V, Michaelis W, Clari P, Gaillard C, Martire L, Reitner J. Cold seep deposits of Beauvoisin (Oxfordian; southeastern France) and Marmorito (Miocene; northern Italy): microbially induced authigenic carbonates. International Journal of Earth Sciences. 1999a;**88**:60-75

[58] Reysenbach AL, Cady SL. Microbiology of ancient and modern hydrothermal systems. Trends in Microbiology. 2001;**9**(2)

[59] Suess E, Carson B, Ritger S, Moore JC, Jones M, Kulm LD, et al., editors. Biological communities at vent sites along the subduction zones off Oregon. The hydrothermal vents of the Eastern Pacific: An overview. Bulletin Biological Society of Washington. 1985;**6**:475-484

[60] MacDonald IR, Bohrmann G, Escobar E, Abegg F, Blanchon P, Blinova V, et al. Asphalt volcanism and chemosynthetic life in the Campeche Knolls, Gulf of Mexico. Science. 2004;**304**:999-1002

[61] Lonsdale P. A deep-sea hydrothermal site on a strike-slip fault. Nature. 1979;**281**:531-534

[62] Lavoie D, Chi G. An Ordovician "Lost City"—Venting serpentinite and life oases on Iapetus seafloor. Canadian Journal of Earth Sciences. 2010;**47**(3):199-207. DOI: 10.1139/E10-013

[63] Schwarzenbach EM, Früh-Green GL, Bernasconi SM, Alt JC, Shanks III WC, Gaggero L, et al. Sulfur geochemistry of

peridotite-hosted hydrothermal systems: Comparing the Ligurian ophiolites with oceanic serpentinites. Geochimica et Cosmochimica Acta. 2012;**91**:283-305. DOI: 10.1016/j.gca.2012.05.021

[64] Hodel F, Macouin M, Trindade RIF, Triantafyllou A, Ganne J, Chavagnac V, et al. Fossil black smoker yields oxygen isotopic composition of Neoproterozoic seawater. Nature Communications. 2018;**9**:1453. DOI: 10.1038/s41467-018- 03890-w

[65] Karson JA, Dick HJB. Tectonics of ridge-transform intersections at the Kane fracture zone. Marine Geophysical Researches. 1983;**6**(1):51-98

[66] Dick HJ, Meyer PS, Bloomer S, Kirby S, Stakes D, Mawer C. Lithostratigraphic evolution of an in-situ sections of ocean layer 3. In: Proceeding of the Ocean Drilling Program, Scientific Results. College Station, Texas. 1991;**118**:439-538

[67] Cannat M, Sauter D, Mendel V, Ruellan E, Okino K, Escartin J, et al. Modes of seafloor generation at a meltpoor ultraslow-spreading ridge. Geology. 2006;**34**:605-608. DOI: 10.1130/G22486.1

[68] Karson JA, Früh-Green GL, Kelley DS, Williams EA, Yoerger DR, Jakuba M. Detachment shear zone of the Atlantis Massif core complex, Mid-Atlantic Ridge, 30 N. Geochemistry, Geophysics, Geosystems. 2006;**7**(6):1-29. DOI: 10.1029/2005GC001109

[69] Cann JR, Blackman DK, Smith DK, McAllister E, Janssen B, Mello S, et al. Corrugated slip surfaces formed at ridgetransform intersections on the Mid-Atlantic Ridge. Nature. 1997;**385**:329-332. DOI: 10.1038/385329a0

[70] Escartín J, Cannat M. Ultramafic exposures and the gravity signature of the lithosphere near the Fifteen Twenty Fracture Zone (Mid Atlantic Ridge, 14-16.5N). Earth Planter Science Letters. 1999;**171**:411-424

[71] Smith DK, Cann JR, Escartin J. Widespread active detachment faulting and core complex formation near 13° N on the Mid-Atlantic Ridge. United Kingdom. Nature. 2006;**442**:440-443. DOI: 10.1038/nature04950

[72] Silantyev SA, Mironenko MV, Novoselov AA. Hydrothermal systems in peridotites of slow-spreading mid-oceanic ridges. Modeling phase transitions and material balance: Down-welling limb of a hydrothermal circulation cell. Petrology. 2009;**17**(2):138-157

[73] Kelley DS, Baross JA, Delaney JR. Volcanoes, fluids, and life at mid-ocean ridge spreading centers. Annual Review of Earth and Planetary Science. 2002;**30**(1):385-491

[74] German CR, Von Damm KL. Hydrothermal processes. In: Elderfield H, editor. The Oceans and Marine Geochemistry: Treatise on Geochemistry. Vol. 6. Elsevier Ltd.; 2003;**6**:181-222

[75] Alt J, Shanks W. Serpentinization of abyssal peridotites from the MARK area, Mid Atlantic Ridge: Sulfur geochemistry and reaction modeling. Geochimica et Cosmochimica Acta. 2003;**67**:641-653

[76] Alt JC, Shanks III WC, Bach W, Paulick H, Garrido CJ, Beaudoin G. Hydrothermal alteration and microbial sulfate reduction in peridotite and gabbro exposed by detachment faulting at the Mid Atlantic Ridge, 15o20 ́N (ODP Leg 209): A sulfur and oxygen isotope study. Geochemistry, Geophysics, Geosystems. 2007;**8**(8). DOI: 10.1029/2007GC001617

[77] Delacour A, Früh-Green G, Bernasconi MS. Sulfur mineralogy and *Deep Sea Biodiversity on the Continents, How It Happens? DOI: http://dx.doi.org/10.5772/intechopen.110697*

geochemistry of serpentinites and gabbro of the Atlantis Massif (IODP Site U1309). Geochimica et Cosmochimica Acta. 2008;**72**:5111-5127

[78] Ildefonse B, Rona PA, Blackman D. Drilling the crust at Mid-Ocean Ridges. An in-depth perspective. Oceanography. 2007;**20**(1):66-77

[79] Sinton CW, Duncan RA, Storey M, Lewis J, Estrada JJ. An oceanic flood basalt province within the Caribbean Plate. Earth and Planetary Science Letters. 1998;**155**:221-235

[80] Pindell J, Barrett S. Geological evolution of the Caribbean region: A plate tectonic perspective. In: Dengo G, Case JE, editors. The Caribbean Region. Boulder, Colorado, USA: Geological Society of America. 1991. DOI: 10.1130/ DNAG-GNA-H

[81] Pindell JL, Kennan L. Tectonic Evolution of the Gulf of Mexico, Caribbean and Northern South America in the Mantle Reference Frame: An Update. Vol. 328. London: Geological Society; 2009. pp. 1-55. DOI: 10.1144/ SP328.1

[82] Lewis J, Draper G, Proenza J, Epaillat J, Jiménez J. Ophiolite-related ultramafic rocks (Serpentinites) in the Caribbean region: A review of their occurrence, composition, origin, emplacement and Ni-laterite soil formation. Geologica Acta. 2006;**4**(1-2): 237-263. DOI: 10.1344/105.000000368

[83] Nívia A. El Complejo Estructural Dagua, Registro de Deformación de la Provincia Litosférica Cretácica Occidental en un Prisma Acrecionario. VII Congreso Colombiano de Geología Tomo III. 1997. pp. 54-67

[84] Wierzbowski H, Joachimski M. Reconstruction of late

Bajocian-Bathonian marine paleoenvironments using carbon and oxygen isotope ratios of calcareous fossils from the Polish Jura Chain (Central Poland). Palaeogeography, Palaeoclimatology, Palaeoecology. 2007;**254**:523-540. DOI: 10.1016/j. palaeo.2007.07.010

[85] Macgregor D. Relationships between seepage, tectonics and subsurface petroleum reserves: Marine and Petroleum Geology. 1993;**10**:606-619

[86] Abrajano TA, Sturchio NC, Bohlke JK, Lyon GL, Poreda RJ, Stevens CM. Methane-hydrogen gas seeps, Zambales ophiolite, Philippines: Deep or shallow origin? Chemical Geology. 1988;**71**(3):211-222. DOI: 10.1016/0009-2541(88)90116-7

[87] Lilley MD, Butterfield DA, Olson EJ, Lupton JE, Macko SA, McDuff RE. Anomalous CH4 and NH4+ concentrations at an unsedimented mid-ocean-ridge hydrothermal system. Nature. 1993;**364**(6432):45-47. DOI: 10.1038/364045a0

[88] Charlou JL, Donval JP, Fouquet Y, Jean-Baptiste P, Holm N. Geochemistry of high H2 and CH4 vent fluids issuing from ultramafic rocks at the rainbow hydrothermal field (36°14′N, MAR). Chemical Geology. 2002;**191**(4):345-359. DOI: 10.1016/S0009-2541(02)00134-1

[89] Proskurowski G, Lilley MD, Olson EJ. Stable isotopic evidence in support of active microbial methane cycling in low-temperature diffuse flows vents at 9°50′N East Pacific rise. Geochimica et Cosmochimica Acta. 2008a;**72**(8):2005-2023. DOI: 10.1016/j. gca.2008.01.025

[90] Meister P, Wiedling J, Lott C, Bach W, Kuhfuß H, Wegener G, et al. Anaerobic methane oxidation inducing carbonate precipitation at abiogenic methane seeps in the Tuscan archipelago (Italy). PLoS One. 2018;**13**(12):1-34. DOI: 10.1371/journal.pone.0207305

[91] Sciarra A, Saroni A, Etiope G, Coltorti M, Mazzarini F, Lott C, et al. Shallow submarine seep of abiotic methane from serpentinized peridotite off the Island of Elba, Italy. Applied Geochemistry. 2019;**100**:1-7. DOI: 10.1016/j.apgeochem.2018.10.025

[92] Eickmann B, Little CTS, Peckmann J, Taylor PD, Boyce AJ, Morgan DJ, et al. Shallow-marine serpentinizationderived fluid seepage in the Upper Cretaceous Qahlah Formation. United Arab Emirates. Geological Magazine. 2021;**158**(9):1561-1571. DOI: 10.1017/ S0016756821000121

[93] Douville E, Charlou JL, Oelkers EH, Bienvenu P, Colon CJ, Donval JP, et al. The rainbow vent fluids (36 14′ N, MAR): The influence of ultramafic rocks and phase separation on trace metal content in Mid-Atlantic Ridge hydrothermal fluids. Chemical Geology. 2002;**184**(1-2):37-48. DOI: 10.1016/ S0009-2541(01)00351-5

[94] Kelley DS, Karson JA, Früh-Green GL, Yoerger DR, Shank TM, Butterfield DA, et al. A serpentinitehosted ecosystem: The Lost City hydrothermal field. Science. 2005;**307**(5714):1428-1434

[95] Fu Q, Lollar BS, Horita J, Lacrampe-Couloume G, Seyfried WE Jr. Abiotic formation of hydrocarbons under hydrothermal conditions: Constraints from chemical and isotope data. Geochimica et Cosmochimica Acta. 2007;**71**(8):1982-1998

[96] Lartaud F, de Rafélis M, Oliver G, Krylova E, Dyment J, Ildefonse B, et al. Fossil clams from a serpentinite-hosted sedimented vent field near the active smoker complex rainbow, MAR, 36o13'N: Insight into the biogeography of vent fauna. Geochemistry, Geophysics, Geosystems. 2010;**11**(8):1-17. DOI: 10.1029/2010GC003079

[97] Castrillón A, Pi-Puig T, Guerrero J, Nuñez-Useche F, Rodriguez A, Canet C. Clay mineralogy and texture of deepsea hydrothermal mudstone associated with the Cerro Matoso peridotite in accreted oceanic crust from Colombia. Journal of South American Earth Sciences. 2022;**117**:1-17. DOI: 10.1016/j. jsames.2022.103886

[98] Klein F, Humphris SE, Guo W, Schubotz F, Schwarzenbach EM, Orsi WD. Fluid mixing and the deep biosphere of a fossil Lost City-type hydrothermal system at the Iberia Margin. Proceedings of the National Academy of Sciences of the United States of America. 2015;**112**(39):12036-12041. DOI: 10.1073/pnas.1504674112

[99] Carothers WW, Adami LH, Rosenbauer RJ. Experimental oxygen isotope fractionation between sideritewater and phosphoric acid liberated CO2 siderite. Geochimica et Cosmochimica Acta. 1988;**52**(10):2445-2450. DOI: 10.1016/0016-7037(88)90302-X

[100] Savin SM, Epstein S. The oxygen and hydrogen isotope geochemistry of clay minerals. Geochimica et Cosmochimica Acta. 1970;**34**(1):25-42. DOI: 10.1016/0016-7037(70)90149-3

[101] Gaudin A, Decarreau A, Noack Y, Grauby O. Clay mineralogy of the nickel laterite ore developed from serpentinised peridotites at Murrin Murrin, Western Australia. Australian Journal of Earth Sciences. 2005;**52**(2):231-241

[102] Irwin H, Curtis C, Coleman M. Isotopic evidence for source of diagenetic *Deep Sea Biodiversity on the Continents, How It Happens? DOI: http://dx.doi.org/10.5772/intechopen.110697*

carbonate forms durign burial of organic-rich sediments. Nature. 1977;**269**:209-213

[103] Palandri JL, Reed MH. Geochemical models of metasomatism in ultramafic systems: Serpentinization, rodingitization, and sea floor carbonate chimney precipitation. Geochimica et Cosmochimica Acta. 2004;**68**(5):1115- 1133. DOI: 10.1016/j.gca.2003.08.006

[104] Proskurowski G, Lilley M, Seewald JS, Früh-Green GL, Olson EJ, Lupton JE, et al. Abiogenic hydrocarbon production at Lost City hydrothermal field. Science. 2008b;**319**(5863):604-607. DOI: 10.1126/science.1151194

[105] Lartaud F, De Rafélis M, Little CTS, Dyment J, Bayon G, Ildefonse B, et al. Ultramafic hydrothermal systems on the rainbow abyssal hill: A wide variety of active and fossil chemosynthetic habitats. InterRidge News. 2011;**20**:32-36

[106] Dias Á, Barriga F. Mineralogy and geochemistry of hydrothermal sediments from the serpentinite-hosted Saldanha hydrothermal field (36°34'N, 33°26'W) at MAR. Marine Geology. 2006;**225**(1-4):157-175. DOI: 10.1016/j. margeo.2005.07.013

[107] Charlou J, Fouquet Y, Bougault H, Donval J, Etoubleau J, Jean-Baptiste P, et al. Intense CH4 plumes generated by serpentinization of ultramafic rocks at the intersection of the 15o20 ́N fracture zone and the Mid-Atlantic Ridge. Geochimica et Cosmochimica Acta. 1998;**62**:2323-2333

[108] Charlou JL, Donval JP, Konn C, Ondreas H, Fouquet Y, Jean-Baptiste P, et al. High production and fluxes of H2 and CH4 and evidence of abiotic hydrocarbon synthesis by serpentinization in ultramafic-hosted hydrothermal systems on the Mid-Atlantic Ridge. In: Rona P, et al., editors. Diversity of Hydrothermal Systems on Slow-Spreading Ocean Ridges. Washington, D. C: AGU; 2010;**188**

[109] Campbell AR, Larson PB. Introduction to stable isotope applications in hydrothermal systems. In: Richards JP, Larson AR, editors. Techniques in Hydrothermal Ore Deposits Geology. Littleton: Society of Economic Geologists; 1998

[110] Alt J, Muehlenbachs K, Honnorez J. An oxygen isotopic profile through the upper kilometer of the oceanic crust, DSDP Hole 504B. Earth and Planetary Science Letters. 1986;**80**(3-4):217-229. DOI: 10.1016/0012-821X(86)90106-8

[111] Hoefs J, Sywall M. Lithium isotope composition of quaternary and tertiary biogene carbonates and a global lithium isotope balance. Geochimica et Cosmochimica Acta. 1997;**61**(13):2679-2690. DOI: 10.1016/ S0016-7037(97)00101-4

[112] Whiticar MJ, Faber E. Methane oxidation in sediment and water column environments—Isotopic evidence. Organic Geochemistry. 1986;**10**(4-6):759-768. DOI: 10.1016/ S0146-6380(86)80013-4

[113] Fry B. Stable Isotope Ecology. New York: Springer; 2008

[114] Templeton AS, Staudigel H, Tebo BM. Diverse Mn (II)-oxidizing bacteria isolated from submarine basalts at Loihi Seamount. Geomicrobiology Journal. 2005;**22**(3-4):127-139. DOI: 10.1080/01490450590945951

[115] Kim S-T, Mucci A, Taylor BE. Phosphoric acid fractionation factors for calcite and aragonite between 25 and 75 °C. Chemical Geology. 2007;**246**:135-146

[116] Aharon P, Graber ER, Roberts HH. Dissolved carbon and δ13C anomalies in

the water column caused by hydrocarbon seep on the northwestern Gulf of Mexico slope. Geo-Marine Letters. 1992;**12**:33-40

[117] Kiel S, Dando PR. Chaetopterid tubes from vent and seep sites: Implications for fossil record and evolutionary history of vent and seep annelids. Acta Palaeontologica Polonica. 2009;**54**(3):443-448. DOI: 10.4202/ app.2009.0022

Section 3
