The Guadalupian was a period of climate change and plate tectonic reconfiguration. Climate changed from glacial conditions at the dawn of the Permian to warm global conditions in the Guadalupian. The Cimmerian terranes migrated from southern Gondwanan paleolatitudes in the Early Permian to subequatorial paleolatitudes by the Middle-Late Permian as the result of the opening of the Neo-Tethys Ocean. This opening was asymmetrical, with higher seafloor spreading rates for the central Cimmerian terranes (central Afghanistan, Karakoram) than for the western terranes (Iran), and it took place contemporaneously with the transformation of Pangea from an Irvingian B to a Wegenerian A-type configuration. During this Early to Middle Permian tectono-climatic transition, bioprovincial patterns evolved rapidly across the southern and northern margins of the opening Neo-Tethys Ocean, making brachiopod palaeobiogeography a useful tool to test its complex opening. Guadalupian (Wordian) brachiopod faunas from Sicily, Tunisia, Turkey, Oman, N Iran, Central Afghanistan, Karakorum, Salt Range and S Thailand have been compared by multivariate analysis to test their similarity and pattern of distribution. The results of cluster analysis and principal coordinate analysis have been placed on an independently derived palaeogeographic reconstruction, allowing to draw the following conclusions: (i) Central Afghanistan and Karakorum faced the Palaeotethys open ocean and were bathed by a palaeoequatorial current that dispersed larvae towards the Tethyan Gulf and the Gondwanan margin. (ii) Tunisia and Sicily (Sosio) were located in the westernmost Tehyan Gulf were thus more prone to isolation with respect to Tethyan open ocean faunas. (iii) N Iran shows affinitities to the Perigondwanan regions of Turkey, Oman, and Salt Range being only slightly detatched from the Gondwanan margin due to the incipient opening of the Neotethys; a current gyre bathed both the Gondwanan margin and the Iranian block. (iv) S Thailand and the Salt Range shows affinitities to the northern Gondwanan margin.

Guadalupian Palaeobiogeography across the Neotethys Ocean / L. Angiolini, G. Muttoni, G. Crippa, V. Verna. ((Intervento presentato al convegno AAPG 2011 International Conference & Exhibition in Milan, Italy tenutosi a Milano nel 2011.

Guadalupian Palaeobiogeography across the Neotethys Ocean.

L. Angiolini
Primo
;
G. Muttoni
Secondo
;
G. Crippa
Penultimo
;
2011

Abstract

The Guadalupian was a period of climate change and plate tectonic reconfiguration. Climate changed from glacial conditions at the dawn of the Permian to warm global conditions in the Guadalupian. The Cimmerian terranes migrated from southern Gondwanan paleolatitudes in the Early Permian to subequatorial paleolatitudes by the Middle-Late Permian as the result of the opening of the Neo-Tethys Ocean. This opening was asymmetrical, with higher seafloor spreading rates for the central Cimmerian terranes (central Afghanistan, Karakoram) than for the western terranes (Iran), and it took place contemporaneously with the transformation of Pangea from an Irvingian B to a Wegenerian A-type configuration. During this Early to Middle Permian tectono-climatic transition, bioprovincial patterns evolved rapidly across the southern and northern margins of the opening Neo-Tethys Ocean, making brachiopod palaeobiogeography a useful tool to test its complex opening. Guadalupian (Wordian) brachiopod faunas from Sicily, Tunisia, Turkey, Oman, N Iran, Central Afghanistan, Karakorum, Salt Range and S Thailand have been compared by multivariate analysis to test their similarity and pattern of distribution. The results of cluster analysis and principal coordinate analysis have been placed on an independently derived palaeogeographic reconstruction, allowing to draw the following conclusions: (i) Central Afghanistan and Karakorum faced the Palaeotethys open ocean and were bathed by a palaeoequatorial current that dispersed larvae towards the Tethyan Gulf and the Gondwanan margin. (ii) Tunisia and Sicily (Sosio) were located in the westernmost Tehyan Gulf were thus more prone to isolation with respect to Tethyan open ocean faunas. (iii) N Iran shows affinitities to the Perigondwanan regions of Turkey, Oman, and Salt Range being only slightly detatched from the Gondwanan margin due to the incipient opening of the Neotethys; a current gyre bathed both the Gondwanan margin and the Iranian block. (iv) S Thailand and the Salt Range shows affinitities to the northern Gondwanan margin.
2011
Settore GEO/01 - Paleontologia e Paleoecologia
Guadalupian Palaeobiogeography across the Neotethys Ocean / L. Angiolini, G. Muttoni, G. Crippa, V. Verna. ((Intervento presentato al convegno AAPG 2011 International Conference & Exhibition in Milan, Italy tenutosi a Milano nel 2011.
Conference Object
File in questo prodotto:
Non ci sono file associati a questo prodotto.
Pubblicazioni consigliate

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2434/166179
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus ND
  • ???jsp.display-item.citation.isi??? ND
social impact