Accueil > Documentations scientifiques > Revues récentes > Madagascar : revue de géographie > Archives > Volume 7, juillet-décembre 1965 > Notes de géomorphologie malgache (première partie)
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Notes de géomorphologie malgache (première partie)
Madagascar : revue de géographie, Volume 7, juillet-décembre 1965 pp:63 - 91Auteur(s) : Vogt J.
Auteur correspondant :
Mots-clés : GEOGRAPHIE PHYSIQUE/GEOLOGIE/GEOMORPHOLOGIE/ MADAGASCAR/SUD OUEST/SAKOA/EST/ANKARIMBELO
Résumé de l’article
[FR]
[MG]
[EN] Well known from its coal field the Sakoa district surprisingly displays in a small area what seems to be a hitherto unrivalled record of the quaternary geomorphological evolution of the interiour part of southern Madagascar. The main features of the Aepyonyan, the local denomination of the Quaternary, more or less, are know since R. Battistini made an intensive survey of the geology and geomorphologie of southernmost Madagascar. At the very limit of Battistini’s survey, they valleys of the rivers Savazy and Sakoa are characterized by : - a high level of wide extension mantled by complex deposits. Grey-greenish sometimes rusty, often mottled silts and sands are overlain by reddish iron-cemented coarse and beds and lenses of gravels often forming consmicious. This high level is not easily correlated with features described southwards by Battistini. - - a medium level showing deep channels filled by boulders often bound by a calcareous cement and by coarse rubified sands. This level may be correlated with Battistini’s high terrasses. - A mostly sandy low level bearing brown soils. This level doubtless represents Battistini’s ubiquitous terrasse At the light Battistini’s survey, an extensive examination of the varied deposits and forms of the Sakoa district and also of the neighbouring larger Onilay valley would doubtless provide new clues for the quaternary geological history of southern Madagascar and help to clarity its climatic sequence