Hydrocarbon Seepage and Carbonate Mound Formation: A Basin Modelling Study From the Porcupine Basin (Offshore Ireland)

Naeth, J.; Primio, Rolando di; Horsfield, Brian; Schaefer, R. G.; Shannon, Patrick M.; Bailey, W. R.; Henriet, J.-P.

doi:10.1111/j.1747-5457.2005.tb00077.x

Cited by 42 publications

(27 citation statements)

References 44 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Note the catenary profile of the Cretaceous and Cenozoic succession, with major stratal surfaces dipping basinwards from the basin edges gas shows were recorded at various levels within the Jurassic, Cretaceous and Cenozoic succession(Croker and Shannon 1995) and demonstrate the presence of an active petroleum system and adequate fluid pathways from the Jurassic source rocks through the overlying stratigraphy Naeth et al (2005). carried out a numerical A.…”

mentioning

confidence: 99%

The evolution of the Porcupine and Rockall basins, offshore Ireland: the geological template for carbonate mound development

Shannon

McDonnell

Bailey

2006

Int J Earth Sci (Geol Rundsch)

Self Cite

View full text Add to dashboard Cite

The margins of the deep-water sedimentary basins west of Ireland contain a number of large clusters (provinces) of spectacular carbonate mounds and build-ups. These basins have a complex development history involving the interplay of rift tectonics, thermal subsidence, igneous activity and oceanographic variations. The Porcupine and Rockall basins both rest upon thin continental crust, the consequence of major rift episodes in Permo-Triassic, Late Jurassic and Early Cretaceous times. Phases of volcanism occurred in the Early Cretaceous and especially in the Early Cenozoic. Fluid flow within the basins is likely to have been controlled by the overall basin geometry and by the distribution and linkage of permeable strata with fault systems, stratal surfaces and unconformities. A number of regional unconformities, controlled by both basin tectonic and regional oceanographic effects, can be mapped and correlated throughout the Porcupine and Rockall basins. The youngest of these unconformities (C10: Early Pliocene) can be traced throughout much of the NW European Atlantic margin. It forms the horizon on which virtually all the carbonate mounds in the basins develop, suggesting a geologically instantaneous mound nucleation and growth event. Although the control on their development is uncertain, the mound clusters show a spatial association with lithified strata, buried contourite and deltaic deposits, slope failure features and with the basin margins. Analysis of these relationships points to a combination of geological and oceanographic processes controlling mound initiation and growth.

show abstract

mentioning

confidence: 99%

The evolution of the Porcupine and Rockall basins, offshore Ireland: the geological template for carbonate mound development

Shannon

McDonnell

Bailey

2006

Int J Earth Sci (Geol Rundsch)

Self Cite

View full text Add to dashboard Cite

show abstract

“…Several potential mechanisms have been described where the initiation phases of coral banks are not only controlled by environmental factors, but also through the mediation of hydrocarbon seepage (Henriet et al 1998;Henriet et al 2001;Hovland and Risk 2003;Naeth et al 2005). According to Hovland et al (1994) the large coral banks located on the northern slope of the Porcupine basin (since then named ' 'Hovland mounds'') are directly connected with Jurassic hydrocarbon reservoirs through faults.…”

Section: Introductionmentioning

confidence: 99%

“…Henriet et al (2001) suggested a short-lived 'triggering' control of the Magellan mound nucleation, related to episodic fluid venting of these underlying reservoirs or to the interglacial destabilization of gas hydrate layers, followed by relaying growth controls, probably from external fluxes. Such a hydrocarbon leakage from Jurassic reservoirs towards the Belgica mound province was considered possible by Naeth et al (2005) through modelling of fluid migration pathways. Although the origin of the Darwin mounds also is related to fluid escape (porewater) and pockmarks (Masson et al 2003), it is clear that fluid escape alone is not sufficient to support coral colonies.…”

Section: Introductionmentioning

confidence: 99%

The Enya mounds: a lost mound-drift competition

Rooij

Huvenne

Blamart

et al. 2008

Int J Earth Sci (Geol Rundsch)

View full text Add to dashboard Cite

The genesis and evolution of cold-water coral banks along the Northeastern Atlantic margin is known to be influenced by several factors, among which the palaeotopography and nature of the coral settling surface, the presence of bottom currents and sediment supply. In this paper, a case study is presented of the Enya mound cluster, located in the southernmost tip of the Belgica mound province, west of Ireland. Below this mound cluster, seismic stratigraphy revealed a yet unmapped local unconformity RD1b, being part of a composite erosion event (RD1). As such, from the Late Miocene to Late Pliocene, at least two erosional events have incised the margin, ending with the final RD1a ''moundbase'' unconformity, acting as a base for the Enya mounds. During the Quaternary the mounds became outgrown and were covered by a mounded contourite drift. In addition, they are closely associated with a cluster of seabed pockmarks. The bottom current regime which became active since the Middle Pleistocene has certainly influenced the fate of this mound cluster. The occurrence of the pockmarks seems to be related to relatively recent fluid migration processes, however leaving an open question if any previous seepage phases were involved in the growth or initiation of the coral banks.

show abstract

“…Geological interpretation of Porcupine Basin stratigraphy in the Belgica province (after Naeth et al, 2005). Arrows = modeled pathways of hydrocarbon-rich gases.…”

Section: Wsw Esementioning

confidence: 99%

“…F4). Two-dimensional basin modeling has been used to evaluate the possible link between hydrocarbon leakage and mound growth (Naeth et al, 2005). Industrial seismic lines and six exploration wells were used to calibrate the burial and thermal history using vitrinite reflectance, bottom hole temperatures, and apatite fission track data (Naeth et al, 2005).…”

Section: Scientific Objectives External Versus Internal Controlsmentioning

confidence: 99%

Expedition 307 summary

Ferdelman¹,

Kano²,

Williams³

et al. 2006

Proceedings of the IODP

View full text Add to dashboard Cite

Challenger Mound is a prominent mound structure covered with dead cold-water coral rubble on the southwest Irish continental margin and was the focus of 12 days of scientific drilling aboard the JOIDES Resolution during Integrated Ocean Drilling Program Expedition 307.Specific drilling objectives included the following:1. Establish whether the mound roots on a carbonate hardground of microbial origin and whether past geofluid migration events acted as a prime trigger for mound genesis. 2. Define the relationship between mound initiation, mound growth phases, and global oceanographic events. 3. Analyze geochemical and microbiological profiles that define the sequence of microbial communities and geomicrobial reactions throughout the drilled sections. 4. Obtain high-resolution paleoclimatic records from the mound section using a wide range of geochemical and isotopic proxies. 5. Describe the stratigraphic, lithologic, and diagenetic characteristics, including timing of key mound-building phases, for establishing a depositional model of cold-water carbonate mounds and for investigating how they resemble ancient mud mounds. Two further sites, located down-and upslope of Challenger Mound, completed a transect to (1) constrain the stratigraphic framework of the slope/mound system, (2) identify and correlate erosional surfaces observed in seismic sections, and (3) investigate potential gas accumulation in the sediments underlying the mound.Drilling revealed that the mound rests on a sharp erosional boundary. Drift sediments below this erosion surface consist of glauconitic and silty sandstone of early-middle Miocene age. The Miocene strata end abruptly in a firmground that is overlain by the late Pliocene-Pleistocene mound succession. The mound flanks are draped by late Pleistocene (<0.26 Ma) silty clay deposits that frequently contain dropstones.The mound succession mainly consists of floatstone and rudstone formed of fine sediments and cold-water branching corals. Pronounced recurring cycles of several meter scales were recognized in carbonate content and color changes and are most probably associated with Pleistocene glacial-interglacial cycles. A role for hy- Proc. IODP | Volume 307 2 Expedition 307 ScientistsExpedition 307 summary drocarbon fluid flow in the initial growth phase of Challenger Mound is not obvious either from lithostratigraphy or from initial geochemistry and microbiology results. We found no significant quantities of gas in the mound or in the subbasal mound sediments, nor were carbonate hardgrounds observed at the mound base.Microbial effects on mound and submound diagenesis are subtle. We detected the methane-sulfate transition only in the Miocene silt and sandstones underlying the mound, where methane concentrations and prokaryotic cell abundances increase with increasing depth. In the mound succession, interstitial water profiles of sulfate, alkalinity, Mg, and Sr suggest a tight coupling between carbonate diagenesis and microbial sulfate reduction. Decomposition of organic matter by...

show abstract

Hydrocarbon Seepage and Carbonate Mound Formation: A Basin Modelling Study From the Porcupine Basin (Offshore Ireland)

Cited by 42 publications

References 44 publications

The evolution of the Porcupine and Rockall basins, offshore Ireland: the geological template for carbonate mound development

The evolution of the Porcupine and Rockall basins, offshore Ireland: the geological template for carbonate mound development

The Enya mounds: a lost mound-drift competition

Expedition 307 summary

Contact Info

Product

Resources

About