{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,22]],"date-time":"2026-09-22T17:04:47Z","timestamp":1790096687088,"version":"4.0.1"},"reference-count":45,"publisher":"American Chemical Society (ACS)","issue":"37","license":[{"start":{"date-parts":[[2026,9,10]],"date-time":"2026-09-10T00:00:00Z","timestamp":1788998400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"}],"funder":[{"DOI":"10.13039\/100016773","name":"Shell Global Solutions International","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100016773","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,9,22]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>This study investigates the directional dependence of gas dispersion in porous media with varying lithology and macroscopic heterogeneity. Eight rock samples, including three carbonates and five sandstones, were examined through CH4\u2013CO2 core-flooding experiments at 300 psi and 65 \u00b0C. Each core was first flooded with CO2 displacing CH4, then the core was inverted 180\u00b0 to quantify the dispersion coefficient in both core orientations. Across most samples, gas dispersion showed directional dependence, with fitted KL values differing by up to 60%. The directional difference depended on the sequence in which the gas mixing front encountered visible heterogeneity. Carbonates exhibited higher dispersion coefficients and smaller directional differences than most sandstone samples, whereas visibly layered sandstones showed larger directional differences. Directional differences decreased with increasing permeability for homogeneous cores but showed no consistent trend in heterogeneous ones, where macroscopic structure dominated flow behavior. Rocks with pronounced macroscopic heterogeneity, such as the Nugget sandstone, experienced the greatest directional differences. These findings indicate that dispersion directionality is governed by a hierarchy of controls, in which lithology, macroscopic heterogeneity, and permeability influence the extent of gas mixing. Rock-dependent in situ fluid mixing can therefore have important implications for subsurface systems engineering in geologic gas storage, particularly in well placement and operational strategy design.<\/jats:p>","DOI":"10.1021\/acsomega.6c05136","type":"journal-article","created":{"date-parts":[[2026,9,11]],"date-time":"2026-09-11T01:01:27Z","timestamp":1789088487000},"page":"55739-55747","source":"Crossref","is-referenced-by-count":0,"title":["Directional Dependence\nof Gas Dispersion in Carbonates\nand Sandstones"],"prefix":"10.1021","volume":"11","author":[{"given":"Tri","family":"Pham","sequence":"first","affiliation":[{"name":"The University of Texas at Austin , , , ,","place":["Austin, Texas, United States, 78712"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3497-0526","authenticated-orcid":true,"given":"Rouhi","family":"Farajzadeh","sequence":"additional","affiliation":[{"name":"Technische Universiteit Delft , , ,","place":["Delft, The Netherlands, 2628 CD"]},{"name":"Shell Global Solutions International B.V. , ,","place":["The Hague, The Netherlands, 2596 HP"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9129-8700","authenticated-orcid":true,"given":"Quoc P.","family":"Nguyen","sequence":"additional","affiliation":[{"name":"The University of Texas at Austin , , , ,","place":["Austin, Texas, United States, 78712"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"316","published-online":{"date-parts":[[2026,9,10]]},"reference":[{"key":"2026092210584834700_cit1","doi-asserted-by":"publisher","first-page":"206","DOI":"10.1017\/S0022112073210662","article-title":"Dynamics of\nFluids in Porous Media","volume":"61","author":"Bear","year":"1973","journal-title":"J. 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