SEISMIX 2024, Abs ac olume
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A c us al-scale sec ion o he NW Ibe ia: de o ma ion mechanisms and
ans e du ing he Alpine comp ession
I. DeFelipea, P. Aya zaa, I. Palome asa, M. Ruizb, J. And ésc, and R. Ca bonellb
aDepa amen o de Geología, Facul ad de Ciencias, Uni e sidad de Salamanca (Spain), ide[email p o ec ed]s, [email p o ec ed]s,
[email protected], bGeosciences Ba celona, GEO3BCN-CSIC, Ba celona (Spain), m [email protected],
amon.ca [email protected], cIns i u Ca og à ic i Geològic de Ca alunya, Ba celona (Spain), Ju enal.And e[email p o ec ed]
O ogen o ma ion, ec onic in e sion and de o ma ion ans e a e p ocesses ha shape pla e bounda ies,
Howe e , he c us al de o ma ion mechanisms ha go e n hese p ocesses a y deeply depending on he
Peninsula comp ises om no h o sou h: i) he pa ially in e ed passi e con inen al No h Ibe ian
Ma gin (NIB), ii) he Can ab ian Moun ains (CM) o med in he no he n bounda y o he Ibe ian
subpla e du ing he Alpine comp ession, and iii) an in apla e ange, he Spanish-Po uguese Cen al
Sys em (SPCS). In addi ion, he CM and SPCS a e sepa a ed by he Due o Cenozoic basin which
ep esen s an ele a ed pla eau (~800 m), whe eas o he sou h o he SPCS, he Mad id Cenozoic basin is
loca ed a 400 m al i ude. He e, we p esen a 650-km long c us al-scale c oss-sec ion going om he
NIB o he sou h o he Mad id Cenozoic basin. The la e is based on new hype bolic mo eou
p ocessing o wide-angle seismic e lec ion/ e ac ion da a and on he ein e p e a ion o p e ious P-
wa e eloci y models. Ou da a show an asymme y o he Moho e lec ions a bo h sides o he SPCS
and deep sub e ical e lec o s o he sou h o he SPCS ha we in e p e as he image o sou h- e gen
c us al-scale hick-skinned h us s. This con as s wi h he de o ma ion pa e n o he CM, whe e
de o ma ion is decoupled be ween he uppe and lowe c us and only he Ibe ian lowe c us subduc s o
he no h eaching a leas 45 km. This c us al a chi ec u e esul s om he in e sion du ing he Alpine
con ac ion o inhe i ed s uc u es and weakness zones: mid-C e aceous ex ensional de achmen s in he
NIB and CM, and la e- o pos -Va iscan g ani oid in usion ha p omp ed c us al-scale aul nuclea ion
in he con ac wi h he hos ocks in he SPCS. He e, he Con ad discon inui y sepa a ing he uppe and
lowe c us was assimila ed du ing g ani oid in usion in he la e-Va iscan ex ension, cons aining he
pa e n used o accommoda e de o ma ion and playing a key ole in he inal con as ing al i udes o he
Acknowledgemen s
This s udy was suppo ed by: The Spanish Na ional Resea ch P og am unde g an s (CGL2014-56548-
P; CGL2016-81964-REDE), he Gene ali a de Ca alunya (2017-SGR-1022) and he Jun a de Cas illa y
León (SA084P20).