http://www.mytopo.com/maps.cfm?mtlat=33.0039&mtlon=-91.16596&z=15
tho originally a wetpoint on the thalweg of the mississippi river when arla was first surveyed in 1806
& tho subsequently stranded in a side chute by a sudden displacement of the river into a new bed
now appears in the satpic overlay to be high & dry on a sandbar or island
owing to more recent processes of avulsion & or accretion
the latest change in its condition is possibly quite recent
because the sandbar was not shown in this position by the latest usgs topo
& i didnt notice the bar when i tried to view the tripoint from the west bank about 10 years ago
or else mistook the bar such as it was at that time for the opposite bank of the river
the tripoint position on this apparently unnamed feature is almost certainly unmarked
but a trace of the old chute
now probably much silted over
is still discernible from space
as is the arkansas louisiana state line converging upon it from the west
so with the help of these traces
& in view of the newfound or improved reliability of the google earth coord registry
it is now possible to estimate the tripoint geoposition in wgs84 to the nearest tenth of a second
as nlat33d00m15s1 & wlong91d09m57s1
for ease of future visitation access
it looks as tho the north end of the sandbar is connected to the west bank by a riprap
as you can see by hitting the hybrid button on the topo
1 comment:
a similar situation has arisen at aroktx in recent years
owing to avulsions & accretions of the red river
but in that case a redefinition of the oktx state line in 2000 has neglected to insert a necessary closing segment between the living vegetation line on the south bank where oktx now runs & the sandbar island that has built up at the location where the tripoint was formerly frozen by a sudden shift of the river bed
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