International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXXV, Part B4. Istanbul 2004
Intern
then all other governmental institutions are responsible to desigr
condense the TUTGA regarding the Large Scale Map and Map new c
Information Production Regulation that is on approval stage. inforn
The n
2.3 Local Geodetic Networks and c
sensin
As is mentioned previously Turkey is a very old country. sensin
Therefore geo-based information transfer is always necessary 1:250
from very past to today and future. As is also mentioned the achie
first technical regulation of Turkey that was forcing land GPS i
Mu Aa bi ee mee tmi a eher ee A Em a surveyors to connect National Geodetic Network for large scale 10 to.
on ro où ai cmt vivra TS applications was approved in 1988. Therefore the mapping and
Figure 2: Turkish Fundamental GPS Network — TUTGA cadastral works made before hand had local vision rather then More
country-wide vision. However people have legal rights on all WGS
Datum of TUTGA is International Terrestrial Reference Frame information collected based on those maps and plans. Hence all maps
1996 (ITRF96) at epoch 1998.0. Therefore it is the part of those must be taken care of and related with current geodetic distor
global network. Which means any data collected or map infrastructure. As an example Figure 3 shows local network image
produced based on TUTGA has a global meaning and is developments of Istanbul by time (Günes et al, 1985 and (Yalm succe
globally identified and valid. However TUTGA needs to be and Maktav, 1995). The latest and the current GPS network of profe:
condensed for large scale mapping applications snd high Ístanbul is not shown on the figure however it has been image
resolution digital data collection. The new regulation that is on established in 1999 based on TUTGA and named as Ístanbul today
approval stage defines the standard rules of condensing GPS Control Network (IGNA) (Ayan et al, 1999). well
strategies of TUTGA. However these condensing processes g prima
have been made since mid 1990 by municipalities for forming
geodetic infrastructure for Urban Information Systems. The 9 IN KARADENIZ K 4
technical specifications of TUTGA can be obtained on Table 2 SU
(Celik et al, 2003).
AVRUPA
Table 2: Technical Specs of TUTGA
Datum ITRF96 8 / toss ; 0 a Remc
Ellipsoid GRS80 : s 4 AN 1 KADIKOY as lat
Number of Control Stations 594 | 13 KARTAL Howe
Common with National Geo. Net. | 91 § Yh ul ASYA 15 gs suppc
Common with Geodynamic Net. 53 S OKMETDANG e NJ $8 17 DERE NI techn
Common with Levelling Net. 181 ET TS iiv Mm EST There
Common with SLR Stations. 5 d SARTYER eue ja m — collec
Density of Control Stations 25-70 km Psy MARMARA DENizi I sil geod:
Density of Control Stations 1315 km”/stn ASE niches posit
Figure 3: Cadastral Network Development of Istanbul by Time :
TUTGA has also been designed as a hierarchical control Tue
network due to largeness of the country. However, as it is As is seen from Figure 3 that first modern cadastral network TUT(
mentioned it is 4D control network and the 4^ dimension is was established in 1911 using plane geometry. Thereafter it Rem
time. Using 4^ dimension of TUTGA tectonic characteristic of. had been partially extended. Most cities of Turkey have similar Comm
ihe country has been taken into account. Therefore velocity scenarios. Therefore existence of all these networks should be infra:
model of TUTGA has been determined by using the control known and the new design of data collection should be made level
stations of TUTGA that are also the member of Geodynamic With respect to the existence of these networks.
Networks. Moreover the second phase of TUTGA GPS t de
observations have been completed in late 2003, therefore the Information about these networks can be obtained from local ha
latest velocity model generated will be much precise to present institutions like regional directory of cadastre, municipality, id
the tectonic characteristic of the country. local government and etc. ud
However there are two main weakness of TUTGA. One of 3. HOWTO USE THESE GEODETIC NETWORKS? i
them is the dense of the control stations; therefore it needs to be : ; ; ; me
condensed. The other one, may be the most important one is to As is mentioned there are several type of geodetic networks in Rem
have less number of common stations with the National Turkey, Even though national One S {he most accepted one for
Geodetic Network. Therefore geo-based information transfer many typ e of mapping app lications, local NENYOIKS are also s Hm v
cannot precisely and reliably be possible without determining used. Therefore any, new applications or technologies are =
regional transformation parameters with additional works from concerned the existence of all network should be investigated expe
National Geodetic Network to TUTGA. and most precise transformation parameters has to be produced ment
for the region. However the latest network is TUTGA. only
General Directorate of Land Registry and Cadastre, General Therefore any kind of mapning WORK 0 date CONSCHON qat vil feno
Commander of Mapping are the main institutions that are be catried qui Should be designed Based on TUIGA and then i i
responsible to take care of TUTGA. However beside these transformation parameters do not exist with other existing s
institutions primarily Provincial Bank and municipalities and Reiworks they have to be determined, ‚Suiely HaRSTOUHaHOR Bor
parameter determination aspect should be considered while appli
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