Preprints
Filtering by Subject: Oil, Gas, and Energy
A data assimilation framework to constrain the driving processes of anthropogenically induced subsidence
Published: 2021-03-25
Subjects: Earth Sciences, Environmental Sciences, Oil, Gas, and Energy, Statistics and Probability
Surface movement can be induced by many human subsurface activities: natural gas production, geothermal heat extraction, ground water extraction, phreatic groundwater level lowering, storage of natural gas and CO2. In this manuscript, we focus on subsidence caused by gas production. While geological interpretations, seismic campaigns and flow modeling often provide a relatively rich pre-existing [...]
Controls on the spatio-temporal patterns of induced seismicity in Groningen constrained by physics-based modeling with Ensemble-Smoother data assimilation
Published: 2021-03-17
Subjects: Earth Sciences, Oil, Gas, and Energy
The induced seismicity in the Groningen gas field, The Netherlands, presents contrasted spatio-temporal patterns between the central area and the south west area. Understanding the origin of this contrast requires a thorough assessment of two factors: (1) the stress development on the Groningen faults, and (2) the frictional response of the faults to induced stresses. Both factors have large [...]
Waste Incinerators Undermine Clean Energy Goals
Published: 2021-02-03
Subjects: Climate, Oil, Gas, and Energy
A national clean energy standard, modeled upon existing state-level Renewable Portfolio Standards, has been proposed to decarbonize the U.S. electric grid. Most such state policies include municipal solid waste incineration as a form of “renewable” energy, despite incineration’s prominent role in perpetuating environmental injustice. This study finds that incinerators emit more greenhouse gas [...]
Ordination analysis in sedimentology, geochemistry and paleoenvironment - background, current trends and recommendations
Published: 2021-02-02
Subjects: Biogeochemistry, Earth Sciences, Environmental Indicators and Impact Assessment, Environmental Monitoring, Geochemistry, Geology, Geomorphology, Geophysics and Seismology, Glaciology, Multivariate Analysis, Oil, Gas, and Energy, Other Earth Sciences, Paleobiology, Paleontology, Sedimentology
Ordination is the name given to a group of methods used to analyze multiple variables without preceding hypotheses. Over the last few decades the use of these methods in Earth science in general, and notably in analyses of sedimentary sources, has dramatically increased. However, with limited resources oriented towards Earth scientists on the topic, the application of ordination analysis is at [...]
New Technologies can Cost-effectively Reduce Oil and Gas Methane Emissions, but Policies will Require Careful Design to Establish Mitigation Equivalence
Published: 2021-01-22
Subjects: Oil, Gas, and Energy
Reducing methane emissions from oil and gas systems is a central component of US and international climate policy. Leak detection and repair (LDAR) programs using optical gas imaging (OGI) based surveys are routinely used to mitigate fugitive emissions or leaks. Recently, new technologies and platforms such as planes, drones, and satellites promise more cost-effective methane mitigation than [...]
Global Liquefied Natural Gas Expansion Exceeds Demand for Coal-to-gas Switching in Paris Compliant Pathways
Published: 2020-12-04
Subjects: Oil, Gas, and Energy, Sustainability
The shift from coal to natural gas (NG) in the power sector has led to significant reductions in carbon emissions. The shale gas revolution that led to this shift is now fueling a global expansion in liquefied natural gas (LNG) export infrastructure. In this work, we assess the viability of LNG expansion to reduce global carbon emissions through coal-to-gas switching in the power sector under [...]
A quantitative assessment of the hydrogen storage capacity of the UK continental shelf
Published: 2020-11-20
Subjects: Oil, Gas, and Energy
Increased penetration of renewable energy sources and decarbonisation of the UK's gas supply will require large-scale energy storage. Using hydrogen as an energy storage vector, we estimate that 150 TWh of seasonal storage is required to replace seasonal variations in natural gas production. Large-scale storage is best suited to porous rock reservoirs. We present a method to quantify the hydrogen [...]
Closing the gap: Explaining persistent underestimation by US oil and natural gas production-segment methane inventories
Published: 2020-11-03
Subjects: Environmental Indicators and Impact Assessment, Oil, Gas, and Energy
Methane (CH4) emissions from oil and natural gas (O&NG) systems are an important contributor to greenhouse gas emissions. In the United States, recent synthesis studies of field measurements of CH4 emissions at different spatial scales are ~1.5x-2x greater compared to official greenhouse gas inventory (GHGI) estimates, with the production-segment as the dominant contributor to this divergence. [...]
The Global Warming Potential Misrepresents the Physics of Global Warming Thereby Misleading Policy Makers
Published: 2020-10-25
Subjects: Atmospheric Sciences, Environmental Sciences, Oil, Gas, and Energy
The Global Warming Potential (GWP) is a widely used metric used to compare the climate change effects of various greenhouse gases. Although GWP has an established role in international climate agreements, GWP does not, in general, describe any specific identifiable impact of greenhouse gas emissions on climate. It is argued here that GWP is unphysical, unintuitive, arbitrary, ignores the time [...]
The Paradox of Increasing Initial Oil Production but Faster Decline Rates in Fracking the Bakken Shale: Implications for Long Term Productivity of Tight Oil Plays
Published: 2020-10-21
Subjects: Oil, Gas, and Energy, Petroleum Engineering
In the US, tight oil is the largest source of liquid hydrocarbons and has driven the country to become the world’s largest oil producer. Eventually many countries will likely be producing very large quantiles of tight oil. However, how robust is tight oil production? The answer to this question will have an impact on the future geographic spread of oil production and will have geopolitical [...]
Bridging the gap between geophysics and geology with Generative Adversarial Networks (GANs)
Published: 2020-08-17
Subjects: Artificial Intelligence and Robotics, Computer Sciences, Databases and Information Systems, Earth Sciences, Environmental Monitoring, Environmental Sciences, Geology, Geomorphology, Geophysics and Seismology, Natural Resource Economics, Oil, Gas, and Energy, Other Earth Sciences, Physical Sciences and Mathematics, Sedimentology, Water Resource Management
Inverse mapping from geophysics to geology is a difficult problem due to the inherent uncertainty of geophysical data and the spatially heterogeneous patterns (structure) in geology. We describe GANSim, a type of generative adversarial networks (GANs) that discovers the mapping between remotely-sensed geophysical information and geology with realistic patterns, with a specially designed loss [...]
Fracture mechanics of rate-and-state faults and fluid injection induced slip
Published: 2020-07-08
Subjects: Earth Sciences, Engineering, Environmental Sciences, Geophysics and Seismology, Oil, Gas, and Energy, Physical Sciences and Mathematics, Physics
Propagation of a slip transient on a fault with rate-and-state dependent friction resembles a fracture which near tip region is characterized by large departure of the slip velocity and fault strength from the steady-state sliding. We develop a near tip solution to describe this unsteady dynamics, and obtain the fracture energy Gc, dissipated in overcoming strength-excursion away from [...]
An agent-based model for estimating emissions reduction equivalence among leak detection and repair programs
Published: 2020-07-02
Subjects: Environmental Sciences, Oil, Gas, and Energy, Physical Sciences and Mathematics
Alternative leak detection and repair (alt-LDAR) programs are being introduced by regulators in North America to provide flexibility in how oil and gas producers manage their fugitive methane emissions. However, emissions reduction equivalence must be established between a proposed program and a regulatory standard. We present LDAR-Sim, an open-source, agent-based numerical model for estimating [...]
Turbulent flow effects in a slickwater fracture propagation in permeable rock
Published: 2020-06-18
Subjects: Earth Sciences, Environmental Sciences, Hydrology, Oil, Gas, and Energy, Physical Sciences and Mathematics, Volcanology
This work is devoted to an analysis of the near-tip region of a hydraulic fracture driven by slickwater in a permeable saturated rock. We consider a steady-state problem of a semi-infinite fracture propagating with constant velocity. The host rock is elastic and homogeneous, and fracture propagates according to linear elastic fracture mechanics. The fluid exchange between the fracture and [...]
Methane concentrations in streams reveal gas leak discharges in regions of oil, gas, and coal development
Published: 2020-06-18
Subjects: Earth Sciences, Environmental Indicators and Impact Assessment, Environmental Monitoring, Environmental Sciences, Geochemistry, Oil, Gas, and Energy, Physical Sciences and Mathematics, Water Resource Management
As natural gas has grown in importance as a global energy source, leakage of methane (CH4) from wells has sometimes been noted. Leakage of this greenhouse gas is important because it affects groundwater quality and, when emitted to the atmosphere, climate. We hypothesized that streams might be most contaminated by CH4 in the northern Appalachian Basin in regions with the longest history of [...]