Elwren Formation

{{more citations needed|date=October 2017}}

{{Infobox rockunit

| name = Elwren Formation

| image =

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| type = Formation

| age = Mississippian

| period = Mississippian

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| region = Indiana and Kentucky

| country = United States

| coordinates =

| unitof = West Baden Group

| subunits =

| underlies = Beech Creek Limestone

| overlies = Reelsville Limestone

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The Elwren Formation is a geologic formation in Kentucky. It preserves fossils dating back to the Carboniferous period.