[tz] Uzbekistan - insufficient location desciption

Tobias Conradi tobias.conradi at gmail.com
Fri May 18 22:57:19 UTC 2012

Below is more information that might help to determine the border of
the Uzbekistan zones. Since there have been changes to the
subdivisions in the region that may contain the border between the
zones, there may be a requirement to establish a new zone, e.g. if
each subdivision only observed one offset at a time.

The issue of insufficient information to determine what geographic
areas are covered by the zones for Uzbekistan had been raised already
2008-09-08 by Eric Muller:
"What is the boundary between Asia/Samarkand and Asia/Tashkent?"

As of today at http://efele.net/maps/tz/world/ it says
This country is covered by two tz timezones, Tashkent and Samarkand.
There is not enough information in the tz data to figure out how
Uzbekistan is divided between them. We use a separation along
first-level administrative divisons that matches WTE."

tzdata2012c/asia says
# Uzbekistan
Zone	Asia/Samarkand	4:27:12 -	LMT	1924 May  2
			4:00	-	SAMT	1930 Jun 21 # Samarkand Time
			5:00	-	SAMT	1981 Apr  1
			5:00	1:00	SAMST	1981 Oct  1
			6:00	-	TAST	1982 Apr  1 # Tashkent Time
			5:00 RussiaAsia	SAM%sT	1991 Sep  1 # independence
[two lines follow which are the same for both zones]
Zone	Asia/Tashkent	4:37:12 -	LMT	1924 May  2
			5:00	-	TAST	1930 Jun 21 # Tashkent Time
			6:00 RussiaAsia	TAS%sT	1991 Mar 31 2:00
			5:00 RussiaAsia	TAS%sT	1991 Sep  1 # independence
[two lines follow which are the same for both zones]
According to the Theory file a zone must only include territory where
the clock's timestamps agreed after 1970-01-01 00:00:00 UTC.

According to "asia"-file between 1930-06-21 and 1981-04-01 Samarkand
had UTC+4 while Tashkent had UTC+5. So there is at least a difference
in timestamp from 1970 until 1981 and the requirements for having at
least two zones are met.

Q1: What were the 1970-01-01 subdivisions located between Samarkand in
the west and Tashkent in the east?

http://www.departments.bucknell.edu/russian/const/36cons01.html gives
1936 CONSTITUTION OF THE USSR ... ARTICLE 26. The Uzbek Soviet
Socialist Republic consists of the Bukhara, Samarkand, Tashkent,
Ferghana, and Khorezm Regions, and the Kara-Kalpak Autonomous Soviet
Socialist Republic.

There is a map that shows Bukhara, Samarkand, Tashkent, Ferghana, and
Khorezm oblasts and the ASSR.

Samarkand Oblast in its east is only bordered by Tashkent Oblast and
Tashkent Oblast in its west is only bordered by Samarkand Oblast.

Syr Darya Oblast may have been formed 1963-02-16 according to

http://statoids.com/uuz.html claims "1963-02-16: Syr-Darya oblast
split from Samarkand."

So 1970-01-01 there have been from west to east
-Samarkand Oblast
-Syr-Darya Oblast
-Tashkent Oblast

The territories of these entities might contain the border between
Asia/Tashkent and Asia/Samarkand.

Q2: What changes to subdivisions did occur after 1970-01-01?
http://encyclopedia2.thefreedictionary.com/Syr+Darya+Oblast says "In
1973 a large part of the oblast’s territory was transferred to the
newly formed Dzhizak Oblast.", while http://statoids.com/uuz.html
claims "1973-12-29: Dzhizak oblast split from Samarkand."

According to ru WP in 1982 and according to
http://statoids.com/uuz.html in "~1981" Navoiy Oblast has been

According to all three sources in 1973 between Samarkand Oblast in the
west and Tashkent Oblast in the east there seem to have been two new
oblasts compared with 1936, Dzhizak in the west and Syr-Darya in the
east. Corresponding viloyats / provinces today from west to east are
- Samarqand Viloyat
- Jizzakh Viloyat
- Sirdaryo Viloyat
- Tashkent Viloyat

statoids only records one change in that area after these four have
been created, namely "~1996: Tashkent City split from Tashkent

Tobias Conradi
Rheinsberger Str. 18
10115 Berlin


More information about the tz mailing list