230
biodegradation have been discovered in reservoir settings providing another useful
biogeochemical analogy for our understanding of subsurface oil spill fate. At sites
up to 250 km west of the Ixtoc 1 wellhead, increased terpenoid accumulation rates,
decreased retene percentages, and depletion in benthic foraminiferal calcite during
the 1979–1980 interval relative to the remainder of the record were all consistent
with MOSSFA (Schwing et al. unpublished; Schwing and Machain Castillo 2020).
However, there were many variables that confound MOSSFA preservation in the
southern GoM. These include other regional events such as volcanoes and hurricanes, other petroleum sources such as natural seeps and persistent oil and gas
infrastructure, and highly variable bathymetry (e.g., Campeche canyon).
13.6 Conclusions
Considering the impact of MOSSFA on the GoM, these processes should be a new
consideration for real-time oil spill response. In advance of future oil spills, numerical models need to be developed to predict the spatial and temporal formation of
MOSSFA. MOSSFA should also be taken into account for response strategy decisions including freshwater discharge (clay particles and nutrients), surface burning,
and dispersant application. MOSSFA could also potentially be used as concentrating mechanism of mineral-oil-biota aggregates as a response strategy. These factors
are important for oil cleanup efforts and oil budget calculations.
These response decisions must also weigh the ecological trade-off between oiled
coastlines and offshore benthic environments. Enhancing MOSSFA will likely
result in increased impact in the offshore benthic environment, where MOSSFA
constituents have proven to be recalcitrant. However, this may offer a way to predict
the area of benthic ecosystem impact. If MOSSFA is transported to the continental
slope and buried, then this may minimize impact and be the best alternative to
remove oil from biologically active areas. Ultimately, federal and international policies should be discussed and modified with regard to the implications of MOSSFA
prior to future oil spills.
Acknowledgments This research was made possible by a from the Gulf of Mexico Research
Initiative/C-IMAGE. Data are publicly available through the Gulf of Mexico Research Initiative
Information and Data Cooperative (GRIIDC) at https://data.gulfresearchinitiative.org/ (doi:
10.7266/n7-repn-q515, 10.7266/N7F18WRF, 10.7266/n7-jm62-5b12, 10.7266/n7-1k5d-4z68,
10.7266/n7-ynsd-gk73).
References
Aeppli C, Nelson RK, Radovic JR, Carmichael CA, Valentine DL, Reddy CM (2014) Recalcitrance
and degradation of petroleum biomarkers upon abiotic and biotic natural weathering of
Deepwater Horizon oil. Environ Sci Technol 48:6726–6734
P. T. Schwing et al.
biodegradation have been discovered in reservoir settings providing another useful
biogeochemical analogy for our understanding of subsurface oil spill fate. At sites
up to 250 km west of the Ixtoc 1 wellhead, increased terpenoid accumulation rates,
decreased retene percentages, and depletion in benthic foraminiferal calcite during
the 1979–1980 interval relative to the remainder of the record were all consistent
with MOSSFA (Schwing et al. unpublished; Schwing and Machain Castillo 2020).
However, there were many variables that confound MOSSFA preservation in the
southern GoM. These include other regional events such as volcanoes and hurricanes, other petroleum sources such as natural seeps and persistent oil and gas
infrastructure, and highly variable bathymetry (e.g., Campeche canyon).
13.6 Conclusions
Considering the impact of MOSSFA on the GoM, these processes should be a new
consideration for real-time oil spill response. In advance of future oil spills, numerical models need to be developed to predict the spatial and temporal formation of
MOSSFA. MOSSFA should also be taken into account for response strategy decisions including freshwater discharge (clay particles and nutrients), surface burning,
and dispersant application. MOSSFA could also potentially be used as concentrating mechanism of mineral-oil-biota aggregates as a response strategy. These factors
are important for oil cleanup efforts and oil budget calculations.
These response decisions must also weigh the ecological trade-off between oiled
coastlines and offshore benthic environments. Enhancing MOSSFA will likely
result in increased impact in the offshore benthic environment, where MOSSFA
constituents have proven to be recalcitrant. However, this may offer a way to predict
the area of benthic ecosystem impact. If MOSSFA is transported to the continental
slope and buried, then this may minimize impact and be the best alternative to
remove oil from biologically active areas. Ultimately, federal and international policies should be discussed and modified with regard to the implications of MOSSFA
prior to future oil spills.
Acknowledgments This research was made possible by a from the Gulf of Mexico Research
Initiative/C-IMAGE. Data are publicly available through the Gulf of Mexico Research Initiative
Information and Data Cooperative (GRIIDC) at https://data.gulfresearchinitiative.org/ (doi:
10.7266/n7-repn-q515, 10.7266/N7F18WRF, 10.7266/n7-jm62-5b12, 10.7266/n7-1k5d-4z68,
10.7266/n7-ynsd-gk73).
References
Aeppli C, Nelson RK, Radovic JR, Carmichael CA, Valentine DL, Reddy CM (2014) Recalcitrance
and degradation of petroleum biomarkers upon abiotic and biotic natural weathering of
Deepwater Horizon oil. Environ Sci Technol 48:6726–6734
P. T. Schwing et al.