A moving fluid pulse in a fault zone

Abstract

In the Gulf of Mexico, fault zones are linked with a complex and dynamic system of plumbing in the Earth's subsurface. Here we use time-lapse seismic-reflection imaging to reveal a pulse of fluid ascending rapidly inside one of these fault zones. Such intermittent fault 'burping' is likely to be an important factor in the migration of subsurface hydrocarbons.

Along-strike fault core thickness variations of a fault in poorly lithified sediments, Miri (Malaysia)

“…sandy breccia fault-core type, sub-rounded clasts of host rock (sand, sand and silt, clay and organic matter-rich beds) with partly preserved bedding are enclosed in the disaggregated sand material. Vertical migration of oil and gas along seismically resolvable faults has been described by Haney et al (2005) and Cartwright et al (2007). In the West Baram Delta system, hydrocarbon flow along faults has been reported by Sandal (1996), Laird and Morley (2011) and Algar (2012).…”

Hydrocarbon plumbing systems above the Snøhvit gas field: Structural control and implications for thermogenic methane leakage in the Hammerfest Basin, SW Barents Sea

“…If overpressure develops beneath the hydrate layers, exceeding the so called the "critical gas column thickness", fault slip will take place in the overlying sediments (Flemings et al, 2003), allowing overpressure to be periodically relieved as the free gas beneath the GHSZ is bled off (Hornbach et al, 2004), whilst hydrofracture may result in creation of new fault networks. Since leakage along a fault plane may happen periodically or in bursts (Haney et al, 2005), some faults may have been leaking and conducting fluids more than once. Thus, repeated overpressure buildups could have triggered the fluid escape events observed on the two separate chronological surfaces: the URU and the present-day seabed.…”

Basic Research Needs for Geosciences: Facilitating 21st Century Energy Systems

“…A zone of high reflectivity is moving in the northeast direction, which is the up-dip direction. This moving zone of high reflectivity is indicative of fluid migration along the fault (Haney et al 2005). Another example of fluid migration is shown in Figure 15, where CO 2 changes the reflectivity of the seismic image during enhanced oil recovery.…”

“…An example is shown in Figure 38, in which the electrical conductivity in Volcano Island, Italy, is shown to correlate well with the CO 2 flux, temperature and selfpotential. In time-lapse images it is possible to monitor the change in fluid content with time (Haney et al 2005), but this still does not constitute a direct measurement of flow.…”