M239

ALTERNATE NAME/NUMBER- MILE 239

77º 05' 42" S

124º 25' 00" W

2076 Meters

EXECUTIVE COMMITTEE RANGE TRAVERSE

1959-60 Season

Engineer: William H. Chapman

Solar position at Mile 239 is the horizontal datum used to determine the horizontal positions of intersected map control points in the Executive Committee Range.

Elevations determined by altimeter traverse based on Byrd Station elevation of 1530 meters

Wild T-2 used for angular measurements.

Located approximately 17 km E. of the Mount Sidley in the Executive Committee Range.

Station mark - unmonumented snow station.

Surveyed 1959-60.

Horizontal Datum - Position based on the Astronomic Position of M239. Selected intersected station have been tied to the Marie Byrd Land Electronic Traverse of 1966-67-68 (see individual control folders).

Vertical Datum - Elevations determined by altimeter traverse based on Byrd Station elevation of 1530 meters

1959 EXECUTIVE COMMITTEE RANGE TRAVERSE (GAS CACHE)

Traverse starts and ends at Byrd Station, elevation 1530. Stations spaced 3 nautical miles (5 km). The elevations from Byrd Station to Mile 164 can be found in the "Byrd Station 1959-60 Traverse" elevation list. Mile 164 is the same as station called "gas cache". Mile 271 is tied to the Marie Byrd Land Electronic Traverse of 1966-67-68 field seasons. The Marie Byrd Land Electronic Traverse was tied to sea-level by triangulation from the Alexander Mountains in the Edward VII Peninsula area, Grant Island on the western end of the Getz Ice Shelf and Wright Island on the eastern end of the Getz Ice Shelf. The altimeter elevations have been adjusted to agree with the elevations determined from the electronic traverse at the above stated points.