Pomerape

{{short description|Mountain in Chile}}

{{Infobox mountain

| name = Pomerape

| photo = Pomerape-from-parinacota-slopes.jpg

| photo_caption = Pomerape and the saddle below, as seen from south (Parinacota slopes)

| elevation_m = 6282

| elevation_ref = [http://www.difrol.cl/html/02.htm Chilean IGM elevation] {{webarchive|url=https://web.archive.org/web/20070927081447/http://www.difrol.cl/html/02.htm |date=2007-09-27 }}

| location = Bolivia-Chile

| range = Andes

| map = Bolivia

| map_caption =

| map_size = 280

| label_position = bottom

| coordinates = {{coord|18|07|33|S|69|07|39|W|type:mountain_region:BO}}

| topo =

| type = Stratovolcano

| age = Pleistocene

| last_eruption =

| first_ascent =

| easiest_route = snow/ice climb

}}

Pomerape is a stratovolcano lying on the border of northern Chile and Bolivia (Oruro Department, Sajama Province, Curahuara de Carangas Municipality).[http://www.ine.gob.bo/publicaciones/visorPdf.aspx?Codigo=040401&tipo=1 Map of Curahuara de Carangas Municipality and population data]. {{webarchive|url=https://web.archive.org/web/20141111092614/http://www.ine.gob.bo/publicaciones/visorPdf.aspx?Codigo=040401&tipo=1 |date=2014-11-11 }} It is part of the Payachata complex of volcanoes, together with Parinacota Volcano to the south. The name "Payachata" means "twins" and refers to their appearance.{{Cite book|title=The Aymara|volume = 2|last=Schull|first=William J.|date=1990|publisher=Springer Netherlands|isbn=9789401074636|editor-last=Schull|editor-first=William J.|series=Studies in Human Biology|pages=1–18|doi=10.1007/978-94-009-2141-2_1|editor-last2=Rothhammer|editor-first2=Francisco|chapter = Introduction: The Place and the Study}} It hosts glaciers down to elevations of {{Convert|5300-5800|m}}, lower on the northern slope.{{Cite journal|last1=Carrasco|first1=Jorge F.|last2=Osorio|first2=Roberto|author3=Casassa, Gino|date=2008-07-01|title=Secular trend of the equilibrium-line altitude on the western side of the southern Andes, derived from radiosonde and surface observations|journal=Journal of Glaciology|volume=54|issue=186|pages=545|doi=10.3189/002214308785837002|bibcode=2008JGlac..54..538C|doi-access=free}}

Pomerape is a complex of lava domes, accompanied by lava flows which were emplaced atop of the domes.{{cite book |last1=Gonzalez-Ferran |first1=Oscar |title=Volcanes de Chile |date=1994 |publisher=Instituto geografico militar |location=Santiago, Chile |isbn=9789562020541 |page=113 |edition= 1st |language=es}} It was active about 200,000 years ago.{{Cite book|title=Tectonics of the Southern Central Andes|last1=Wörner|first1=Gerhard|last2=Moorbath|first2=Stephen|last3=Horn|first3=Susanne|last4=Entenmann|first4=Jürgen|last5=Harmon|first5=Russel S.|last6=Davidson|first6=Jon P.|author-link7=Leopoldo López Escobar|last7=Lopez-Escobar|first7=Leopoldo|date=1994|publisher=Springer Berlin Heidelberg|isbn=9783642773556|editor-last=Reutter|editor-first=Professor Dr Klaus-Joachim|pages=81|doi=10.1007/978-3-642-77353-2_5|editor-last2=Scheuber|editor-first2=Dr Ekkehard|editor-last3=Wigger|editor-first3=Dr Peter J.}} The lava domes formed first and were later buried by the actual volcanic cone, which unlike the rhyolitic-dacitic domes is formed by hornblende andesite.{{Cite journal|last1=Wörner|first1=G.|last2=Harmon|first2=R. S.|last3=Davidson|first3=J.|last4=Moorbath|first4=S.|last5=Turner|first5=D. L.|last6=McMillan|first6=N.|last7=Nyes|first7=C.|author-link8=Leopoldo López Escobar|last8=Lopez-Escobar|first8=L.|last9=Moreno|first9=H.|date=1988-09-01|title=The Nevados de Payachata volcanic region (18°S/69°W, N. Chile)|journal=Bulletin of Volcanology|language=en|volume=50|issue=5|pages=287–303|doi=10.1007/BF01073587|bibcode=1988BVol...50..287W|issn=0258-8900|hdl=2027.42/47805|s2cid=129099050 |url=https://deepblue.lib.umich.edu/bitstream/2027.42/47805/1/445_2005_Article_BF01073587.pdf|hdl-access=free}} The "Chungará Andesites" and lava dome complex of Parinacota were laid down at this time.{{Cite journal|last1=Hora|first1=J. M.|last2=Singer|first2=B. S.|last3=Worner|first3=G.|title=Volcano evolution and eruptive flux on the thick crust of the Andean Central Volcanic Zone: 40Ar/39Ar constraints from Volcan Parinacota, Chile|journal=Geological Society of America Bulletin|volume=119|issue=3–4|pages=343–362|doi=10.1130/b25954.1|bibcode=2007GSAB..119..343H|year=2007}} Pomerape is associated with an adventive vent that has erupted mafic magmas. The main cone was last active 106,000 +- 7,000 years ago,{{Cite journal|last1=Wörner|first1=Gerhard|last2=Hammerschmidt|first2=Konrad|last3=Henjes-Kunst|first3=Friedhelm|last4=Lezaun|first4=Judith|last5=Wilke|first5=Hans|date=2000-12-01|title=Geochronology (40Ar/39Ar, K-Ar and He-exposure ages) of Cenozoic magmatic rocks from Northern Chile (18-22°S): implications for magmatism and tectonic evolution of the central Andes|url=http://www.scielo.cl/scielo.php?script=sci_abstract&pid=S0716-02082000000200004&lng=es&nrm=iso&tlng=en|journal=Revista Geológica de Chile|volume=27|issue=2|pages=205–240|issn=0716-0208}} the adventive vent is dated to 205,000 ± 24,000 years ago.{{cite book |last1=Gonzalez-Ferran |first1=Oscar |title=Volcanes de Chile |date=1994 |publisher=Instituto geografico militar |location=Santiago, Chile |isbn=9789562020541 |page=113 |edition= 1st}}

Climbing the volcano is alpine grade PD by the east ridge.{{cite book |last1=Biggar |first1=John |title=The Andes - A Guide for Climbers and Skiers |date=2020 |publisher=Andes |location=Scotland |isbn=978-0-9536087-6-8 |page=192 |edition=5th}} Harder routes exist on the south face, sometimes on 50+ degree snow/rubble slope. For these routes a camp can be established at {{convert|5,300|m|ft|-1}} at the saddle between Parinacota and Pomerape. Depending on the season, the main difficulty can be penitentes (tall ice-blade needles), which make the ascent physically difficult or impossible.