Hydrocarbon leakage interpreted on seismic data

Løseth, Helge; Gading, M.; Wensaas, Lars

doi:10.1016/j.marpetgeo.2008.09.008

Cited by 335 publications

(259 citation statements)

References 42 publications

Supporting

Mentioning

247

Contrasting

Unclassified

Order By: Relevance

“…This interpretation is based on samples of 475 the well Lapa and on seismic observations of internal stratification and progradational 476 patterns in the mounds. Another strong argument in support of this is the observation of 477 pulled-up layers located below of some mounds, as increased seismic velocity by carbonate-478 cemented sediments and carbonate itself may produce this effect (Løseth et al, 2009). 479…”

Section: Interpretation Of the Buried Eocene Mounded Structures 473mentioning

confidence: 99%

“…8, 9). The suppressed amplitudes of the 432 seafloor reflector might be explainable by partial gas saturation of the seafloor sediments 433 (Crutchley et al, 2010) and the amplitude suppression within the GHSZ could be related to 434 amplitude and signal reduction caused by the presence of gas (Løseth et al, 2009). However, 435 this interpretation is made tentatively, because processing parameters could have 436 compromised true amplitudes in this area of the GHSZ and the seafloor.…”

Section: The Southern Part Of the Basin: 292mentioning

confidence: 99%

See 1 more Smart Citation

Distribution of hydrocarbon leakage indicators in the Malvinas Basin, offshore Argentine continental margin

et al. 2012

View full text Add to dashboard Cite

show abstract

Section: Interpretation Of the Buried Eocene Mounded Structures 473mentioning

confidence: 99%

Section: The Southern Part Of the Basin: 292mentioning

confidence: 99%

Distribution of hydrocarbon leakage indicators in the Malvinas Basin, offshore Argentine continental margin

et al. 2012

View full text Add to dashboard Cite

show abstract

“…They are described in different ways in the literature as columnar disturbances, wipeout zones, dimmed and distorted amplitudes in seismic data (Andresen and Huuse, 2011;Berndt, 2005;Heggland, 1998;Heggland et al, 1999;Hustoft et al, 2010;Løseth et al, 2009). The gas chimneys in this study are associated with high-amplitude anomalies (HAAs) at their roof zones (Figure 1.2a).…”

Section: Gas Chimneysmentioning

confidence: 99%

“…Seismic high-amplitude anomalies represent the change in acoustic properties related to lithology or sub-surface fluid accumulations (Alves et al, 2015;Calvès et al, 2008;Løseth et al, 2009). Direct hydrocarbon indicators (DHI's) such as bright spots, flat spots, polarity reversal etc., are seismic high-amplitude anomalies related to hydrocarbons in the subsurface (Løseth et al, 2009).…”

Section: Seismic High-amplitude Anomalies (Shaa)mentioning

confidence: 99%

Deep-seated faults and hydrocarbon leakage in the Snøhvit Gas Field, Hammerfest Basin, Southwestern Barents Sea

Mohammedyasin

Lippard

Omosanya

et al. 2016

Marine and Petroleum Geology

View full text Add to dashboard Cite

High-quality 3D seismic data are used to analyze the history of fault growth and hydrocarbon leakage in the Snøhvit Field, southwestern Barents Sea. The aim of this work is to evaluate the role of tectonic fracturing as a mechanism driving fluid-flow in the study area. To achieve this aim, an integrated approach including seismic interpretation, multiple seismic attribute analysis, fault modeling and displacement analysis was used.The six major faults in the study area are dip-slip normal faults which are characterized by complex lateral and vertical segmentation. The three main episodes of fault reactivation interpreted were in late Jurassic (Kimmeridgian), early Cretaceous and Paleocene times. Fault reactivation in the study area is mainly through dip-linkage. Throw-distance plots of the representative faults also revealed along-strike linkage and multi-skewed C-type profiles. The throw profiles show that faults in the study area evolved through polycyclic activity involving both blind propagation, syn-sedimentary activity and that they have their maximum displacement at the reservoir zone. The expansion and growth indices provide evidence for coeval fault activity with sedimentation and interaction of the faults with a free surface during their evolution.

show abstract

“…Submarine seepage areas originate from the migration of methane-rich fluids and their discharge at the seafloor through peculiar morphologic features such as mud volcanoes (e.g., Krastel et al, 2003;Løseth et al, 2009), pockmarks (e.g., Hovland et al, 2002;Sultan et al, 2014) and mud diapirs (e.g., Rovere et al, 2014). In such areas, faults may act as plumbing systems, favoring the uprising of fluids from deep-seated sources, which can affect at different degrees the diagenesis of marine sediments (e.g., Hein et al, 2006).…”

Section: Introductionmentioning

confidence: 99%

Authigenic minerals from the Paola Ridge (southern Tyrrhenian Sea): Evidences of episodic methane seepage

Franchi

Rovere

Gamberi

et al. 2017

Marine and Petroleum Geology

View full text Add to dashboard Cite

a b s t r a c tPaola Ridge, along the NW Calabrian margin (southern Tyrrhenian Sea), is one of the few reported deep sea sites of precipitation of authigenic carbonates in the Tyrrhenian Sea. Here, the changing composition of the seeping fluids and the dynamic nature of the seepage induced the precipitation of pyrite, siderite and other carbonate phases. The occurrence of this array of authigenic precipitates is thought to be related to fluctuation of the sulfate-methane transition zone (SMTZ).Concretions of authigenic minerals formed in the near sub-bottom sediments of the Paola Ridge were investigated for their geochemical and isotopic composition. These concretions were collected in an area characterized by the presence of two alleged mud volcanoes and three mud diapirs. The mud diapirs are dotted by pockmarks and dissected by normal faults, and are known for having been a site of fluid seepage for at least the past 40 kyrs. Present-day venting activity occurs alongside the two alleged mud volcanoes and is dominated by CO 2 -rich discharging fluids. This discover led us to question the hypothesis of the mud volcanoes and investigate the origin of the fluids in each different domed structure of the study area.In this study, we used stable isotopes (carbon and oxygen) of carbonates coupled with rare earth element (REE) composition of different carbonate and non-carbonate phases for tracing fluid composition and early diagenesis of authigenic precipitates. The analyses on authigenic precipitates were coupled with chemical investigation of venting gas and sea-water.Authigenic calcite/aragonite concretions, from surficial sediments on diapiric structures, have depleted values. The siderite REE pattern shows consistent LREE (light REE) fractionation, MREE (medium REE) enrichment and positive Gd and La anomalies. As shown by the REE distribution, the 13 C-depleted composition and their association with chemosymbiotic fauna, calcite/aragonite precipitated at time of moderate to high methane flux close to the seafloor, under the influence of bottom seawater. Authigenic siderite, on the other hand, formed in the subseafloor, during periods of lower gas discharges under prolonged anoxic conditions within sediments in equilibrium with 13 C-rich dissolved inorganic carbon (DIC) and 18 O-rich water, likely related to methanogenesis and intermittent venting of deep-sourced CO 2 .

show abstract

Hydrocarbon leakage interpreted on seismic data

Cited by 335 publications

References 42 publications

Distribution of hydrocarbon leakage indicators in the Malvinas Basin, offshore Argentine continental margin

Distribution of hydrocarbon leakage indicators in the Malvinas Basin, offshore Argentine continental margin

Deep-seated faults and hydrocarbon leakage in the Snøhvit Gas Field, Hammerfest Basin, Southwestern Barents Sea

Authigenic minerals from the Paola Ridge (southern Tyrrhenian Sea): Evidences of episodic methane seepage

Contact Info

Product

Resources

About