Sequential deformation of plains at the margins of Alpha Regio, Venus: Implications for tessera formation

Details Sequential deformation of plains at the margins of Alpha Regio, Venus: Implications for tessera formation Sequential deformation of plains at the margins of Alpha Regio, Venus: Implications for tessera formation

Jul 2000

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2000m%26ps...35..667g&link_type=abstract

Meteoritics & Planetary Science, vol. 35, no. 4, pp. 667-687 (2000).

Physics

9

Scientific paper

The boundaries between the highly deformed tessera terrain and adjacent volcanic plains are primarily those of embayment, where the tessera are stratigraphically older than the plains. Previous studies show that less than three percent of these boundaries display evidence of tectonic tilting after the emplacement of the plains. One of these unusual boundaries is the western margin of Alpha Regio tessera, a zone ~100 km in width that separates the plains from the interior structures of Alpha. This zone is characterized by margin parallel, fine scale (1-5 km) fractures, graben and ridges that truncate and postdate the broad scale (10-30 km) ridges and troughs of the interior of Alpha. The western margin is embayed by several volcanic plains units which are progressively tilted and deformed by graben with closer proximity to Alpha Regio. The earliest deformation of the plains consists of NE trending graben ~ 1 km in width that are similar in morphology and spacing to graben that deform intratessera plains and plains at the eastern boundary of Alpha. NW-trending graben then formed over an interval marked by the emplacement of two additional plains units; their similarity to NW-trending structures emanating from Eve corona and the Lada Terra rift suggests a possible genetic relationship. The tilting of the plains adjacent to western Alpha implies relative vertical movement of the margin, either uplift of tessera or downwarping of plains subsequent to the formation and relaxation of the interior of Alpha Regio. Subsidence of plains at this locale is supported by the presence of a basin to the west of Alpha surrounded by a fracture belt contiguous with western Alpha. Thus the fractures and deformation at the western boundary of Alpha may be related to the formation of a basin to the west of Alpha with some influence from the northernmost extension of the Lada Terra rift. Such a basin is not present at a section along the eastern boundary of Alpha Regio, where the origin of tilted plains remains equivocal. We conclude that the deformation along the western margin of Alpha Regio is not directly related to the process of tessera formation, but is rather an example of tessera modification, and is consistent with the stratigraphic position of tessera as the oldest unit observed on Venus.

Affiliated with

Also associated with

No associations

Rating

Sequential deformation of plains at the margins of Alpha Regio, Venus: Implications for tessera formation does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Sequential deformation of plains at the margins of Alpha Regio, Venus: Implications for tessera formation, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Sequential deformation of plains at the margins of Alpha Regio, Venus: Implications for tessera formation will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1730581