Physical constraints on geologic CO2 sequestration in low-volume basalt formations

Abstract

Deep basalt formations within large igneous provinces have been proposed as target reservoirs for carbon capture and sequestration on the basis of favorable CO 2 -water-rock reaction kinetics that suggest carbonate mineralization rates on the order of 10 2 -10 3 d. Although these results are encouraging, there exists much uncertainty surrounding the infl uence of fracture-controlled reservoir heterogeneity on commercial-scale CO 2 injections in basalt formations. This work investigates the physical response of a low-volume basalt reservoir to commercial-scale CO 2 injections using a Monte Carlo numerical modeling experiment such that model variability is solely a function of spatially distributed reservoir heterogeneity. Fifty equally probable reservoirs are simulated using properties inferred from the deep eastern Snake River Plain aquifer in southeast Idaho, and CO 2 injections are modeled within each reservoir for 20 yr at a constant mass rate of 21.6 kg s -1 . Results from this work suggest that (1) formation injectivity is generally favorable, although injection pressures in excess of the fracture gradient were observed in 4% of the simulations; (2) for an extensional stress regime (as exists within the eastern Snake River Plain), shear failure is theoretically possible for optimally oriented fractures if S h ≤ 0.70S V ; and (3) low-volume basalt reservoirs exhibit sufficient CO 2 confi nement potential over a 20 yr injection program to accommodate mineral trapping rates suggested in the literature.

A probabilistic assessment of geomechanical reservoir integrity during CO2sequestration in flood basalt formations

“…As a result, geomechanical reservoir integrity has become an important criterion for numerical model‐based risk assessment in CCS reservoir siting . In order to address this problem, stochastic methods have been increasingly deployed to understand how spatial, parametric, and geologic uncertainty affects CCS reservoir performance . For example, Pollyea et al .…”

“…In order to address this problem, stochastic methods have been increasingly deployed to understand how spatial, parametric, and geologic uncertainty affects CCS reservoir performance . For example, Pollyea et al . develop and implement ensemble simulation methods to quantify spatially variable sealing behavior within the low‐volume Snake River Plains basalts.…”

“…Stochastic simulation methods have been gaining traction as a way to bound the uncertainties associated with heterogeneous reservoirs because spatially variable properties, such as permeability, cannot be upscaled according to simple averaging rules . It is the uncertainty of permeability distribution at these larger scales that can have a substantial impact on the results of hydrogeologic models . For example, constraining permeability at regional scales has implications for studying geological formations that contain multiple resources (e.g., groundwater, geothermal, and carbon storage) .…”

Evidence for tectonic, lithologic, and thermal controls on fracture system geometries in an andesitic high‐temperature geothermal field

“…Non sedimentary rocks are increasingly recognized as reservoirs able to produce fluids. Volcanic formations host geothermal [ Arnórsson , ; Nemčok et al , ; Wilson and Rowland , ], groundwater [ Lachassagne et al , ], hydrocarbon [ Feng , ], and mineral [ Spörli and Cargill , ] resources, while also being capable of storing unwanted CO 2 [ Pollyea et al , ; Matter et al , ] and radioactive waste [ Chen et al , ], and capable of supporting surface engineering projects [ Alemdag , ]. The geometry of vesicles and fractures in volcanic units has been extensively studied in outcrops [e.g., DeGraff and Aydin , ; Gudmundsson , ; Conway et al , ] but can be difficult to quantify in reservoirs due to sparse core and wireline logging measurements.…”

“…Non sedimentary rocks are increasingly recognized as reservoirs able to produce fluids. Volcanic formations host geothermal [Arnórsson, 1995;Nemčok et al, 2004;Wilson and Rowland, 2016], groundwater [Lachassagne et al, 2014], hydrocarbon [Feng, 2008], and mineral [Spörli and Cargill, 2011] resources, while also being capable of storing unwanted CO 2 [Pollyea et al, 2014;Matter et al, 2016] and radioactive waste [Chen et al, 2001], and capable of supporting surface engineering projects [Alemdag, 2015]. The geometry of vesicles…”