Ryugase Group

{{Infobox rockunit

| name = Ryugase Group

| image =

| caption =

| type = Geological formation

| age = Late Santonian-
Early Campanian
~{{fossil range|85|72}}

| period = Campanian

| prilithology = Mudstone

| otherlithology =

| namedfor =

| namedby =

| region = Sakhalin Oblast

| country = {{RUS}}

| coordinates = {{coord|47.2|N|142.5|E|display=inline,title}}

| paleocoordinates = {{coord|51.9|N|130.0|E|display=inline}}

| unitof =

| subunits =

| underlies =

| overlies = Yezo Group

| thickness =

| extent = Sakhalin Island

| area =

| map = {{Location map+ | Russia

| relief = 1

| width = 300

| float = center

| places =

{{Location map~ | Russia

| lat_deg = 47.2

| lon_deg = 142.5

| mark = Lightgreen pog.svg

| marksize = 10

}}

}}

| map_caption =

}}

The Ryugase Group is a geological formation on Sakhalin Island in far eastern Russia whose strata date back to the Late Cretaceous.[https://paleobiodb.org/classic/displayCollResults?collection_no=38138 Kawakami Colliery, Sakhalin] at Fossilworks.org