Monument evolution Original monuments were mainly steel pins in bedrock which required tripod setups Starting in 1995: IVTRAN designed fixed-heights were installed. Simplified setup. Three recovery marks installed for each original monument After 1995, measurements made on the recovery marks rather than original marks With the original marks and fixed height marks, for many stations two independent velocity estimates (results shown later) 12540Lec23 Analysis methods Prior to 1995; selected IGS from Europe, Asia and Australia included in the analysis of regional data After 1995 when pol2 became an IGs site and was routinely included in the IGs analysis; only local sites included in the MIT analysis Using GAMIT/GLOBK; regional analyses are included in the Scripps Institution of Oceanography IGS (SOPAC)analysis including orbit improvement(more mportant in early data ftp: /garner. ucsd. edu/pub/hfiles Campaigns are combined with SOPAC h-files for velocity field and repeatability analys05/12/03 12.540 Lec 23 7 Monument evolution • which required tripod setups • installed. Simplified setup. Three recovery marks installed for each original monument. • After 1995, measurements made on the recovery marks rather than original marks. • With the original marks and fixed height marks, for many stations two independent velocity estimates (results shown later) Original monuments were mainly steel pins in bedrock Starting in 1995: IVTRAN designed fixed-heights were Analysis methods • Prior to 1995; selected IGS from Europe, Asia and Australia included in the analysis of regional data • After 1995 when POL2 became an IGS site and was routinely included in the IGS analysis; only local sites included in the MIT analysis • Using GAMIT/GLOBK; regional analyses are included in the Scripps Institution of Oceanography IGS (SOPAC) analysis including orbit improvement (more important in early data). ftp://garner.ucsd.edu/pub/hfiles • Campaigns are combined with SOPAC h-files for velocity field and repeatability analyses. 05/12/03 12.540 Lec 23 8 4