nieuwe zoekopdracht
[ meld een fout in dit record ]mandje (0): toevoegen | toon Print deze pagina

Pre- and post-Marinoan carbonate facies of the Democratic Republic of the Congo: glacially- or tectonically-influenced deep-water sediments?
Delpomdor, F.; Eyles, N.; Tack, L.; Preat, A. (2016). Pre- and post-Marinoan carbonate facies of the Democratic Republic of the Congo: glacially- or tectonically-influenced deep-water sediments? Palaeogeogr. Palaeoclimatol. Palaeoecol. 457: 144-157. https://hdl.handle.net/10.1016/j.palaeo.2016.06.014
In: Palaeogeography, Palaeoclimatology, Palaeoecology. Elsevier: Amsterdam; Tokyo; Oxford; New York. ISSN 0031-0182; e-ISSN 1872-616X, meer
Peer reviewed article  

Beschikbaar in  Auteurs 

Trefwoord
    Marien
Author keywords
    Neoproterozoic; Snowball Earth; Debrites; Deep-water carbonates;Diamictite; Tectonics

Auteurs  Top 
  • Delpomdor, F.
  • Eyles, N.
  • Tack, L.
  • Preat, A.

Abstract
    The upper carbonate-rich parts of the West Congo Supergroup (similar to 1000-560 Ma) from the Democratic Republic of the Congo have hitherto been considered as a record of abrupt eustatic and climatic events accompanying glaciation and deglaciation of a Snowball Earth-type Marinoan ice age that was of global extent. These strata have however never been investigated in detail. Results of new sedimentological work at key outcrops over a 1300 km outcrop belt show that pre- and post-Marinoan carbonates are respectively, storm-influenced sediments deposited principally in a mid/outer-ramp setting, and deep-water slope carbonates (calicturbidites) representing a lobe-fringe or levee-overbank setting. The Upper Diamictite Formation held previously by some to be a subglacial tillite, comprises gravity flows (debrites) deposited in deep water below wave base along the unstable margins of a carbonate ramp. A direct glacial influence on sedimentation for diamictites or any accompanying fades cannot be readily identified. Sedimentary facies reported here primarily record the presence of deep-water submarine to alluvial fan systems related to extensional tectonic processes of the central-southern Macailbas Basin (now located in Brazil) between 700 Ma and 660 Ma followed by the 630-Ma onset of the pre-collisional magmatic arc in the Aracuai-West Congo Orogen. No extreme short-lived climatic or eustatic events of a Snowball Earth-type ice age are recorded in the studied succession, which primarily reflects long-term overriding regional tectonic controls resulting in diachronous sedimentation along the western margin of the Congo Craton.

Alle informatie in het Integrated Marine Information System (IMIS) valt onder het VLIZ Privacy beleid Top | Auteurs 
IMIS is ontwikkeld en wordt gehost door het VLIZ, voor meer informatie contacteer .