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'''BraVSQ''' Oak Chronology for the region Västra Götaland by Alf Bråthen. It was originally published in the book: Alf Bråthen: ''Dendrokronologisk serie från västra Sverige 831-1975''. Rapport RAÄ 1982:1. ISBN 91-7192-511-2.
'''BrVQ'''. In 1982<ref>Alf Bråthen: ''Dendrokronologisk serie från västra Sverige 831-1975''. Rapport RAÄ 1982:1. ISBN 91-7192-511-2</ref> and 1983<ref name="Bråthen1983">Alf Bråthen: ''The tree-ring chronology of Western Sweden 753-1720'' in: Dendrokronologiska Sällskapet: Meddelanden 6, 1983.</ref> [[Alf Bråthen]] published [[Quercus]] Master Chronologies for Western Sweden, mainly the historical province Västergötland, although he to some extend mixed with samples from [[Halland]] in the chronologies from 1983. He calls them simply "Block 1", "Block 2", "Block 2b", "Block 3", "Block 4" and "Block 5", but we will instead use the identities [[BrVQ1]], [[BrVQ2]], [[BrVQ3]], [[BrVQ4]], [[BrVQ5]]. All of them except "Block 2b"/BrVQ2b are useful chronologies even if "block 3" needs to be redated. The measurements were originally done in 0.1 mm resolution, but the average series are given in 0.01 mm resolution.


In the book four different Chronologies are given, with annual average values and the number of measurements behind each value. There are also detailed documentation about the origins of each sample. The four chronologies are originally named: "Block 1", "Block 2", "Block 2b" and "Block 3". Unfortunately there are some severe errors in the material, which have to be corrected before the chronologies can be used. The wrong date for the Lödöse Chronology was discovered soon after the publication, and a corrected (and enlarged) chronology was published by Bråthen later [ref needed].  
1983 he calls Block 2b "superseded", and in fact it contains severe mistakes which is [[BrVQ2b|revealed by an analysis]], which was done before I become aware of his corrections in the publication 1983.  


Still the material from the book is very valuable and useful, when missdatings are corrected and bad sequences are removed. The measurements were originally done in 0.1 mm resolution, but the average series are given in 0.01 mm resolution.  
A disadvantage of the regional references published in the supplement 1983 (BrVQ4 and BrVQ5) are the mixing material also from [[Halland]]. It would have been better if the material from [[Västergötland]]/[[Diocese of Skara]] had been kept separated from the Halland material. Now we do not have that "clean" local Västergötland/Skara references as we might have had otherwise. The local Halland reference, [[HallandQU]], is now partly based on the same samples as "block 4" and "Block 5".  


==An analysis of the BraVSQ-material==
In addition to the five BrVQ1-5 chronologies, also two weighted chronologies compiled of BrVQ1-3 by [[Torbjörn Axelson]]. They are not very meaningful but sometimes mentioned in dating reports and therefor in need of documentation. ''BraVSQ'' and ''BVSQgt4''. In the later all sequences with less than four samples depth was removed.
For the following analysis, I have used four independent oak-chronologies: [[OlandQUSP]], [[WestDK]], [[BohusRec]] and [[HllndQUB]] (see [[List of references useful in southern and central Scandinavia#Quercus references useful in Scandinavia|List of references]]). The documentation and result of this analysis is available at http://www2.hemsida.net/taxelson/dendro/BrathenEk.zip ([http://www.webcitation.org/5hPagdLcW WebCite]). A weighted chronology of correct and corrected blocks when at least four samples are present is available at http://www2.hemsida.net/taxelson/dendro/BraVSQ.dec .  


===BrVQ1===
'''Block 1'''. Recent: 1615-1975. At least 4 samples depth: 1634-1974, 9 contemporary stems as best. No problems found.


===Block 1===
===BrVQ2===
'''Recent:''' 1615-1975. At least 4 samples depth: 1634-1974, 9 contemporary stems as best. No problems found.
'''Block 2'''. Historical: 1337-1804. At least 4 samples depth: 1380-1779, 16 contemporary stems as best. Bråthen 1983 do not reports any problems.<ref name="Bråthen1983"></ref>. Known problem:
*Value for 1650 is missing.


===Block 2===
===BrVQ2b===
'''Historical:''' 1337-1804. At least 4 samples depth: 1380-1779, 16 contemporary stems as best. Problems:
'''Block 2b'''. Useless. See [[BrVQ2b]] for details.
* The period 1554-1613 has almost zero-correlation towards other references, and has to be removed. It is obviously erroneous. The reason for this problem is not yet known.
*Value for 1650 is missing.  


===Block 2b===
===BrVQ3===
'''Historical:''' 1197-1490
'''Block 3'''. Lödöse, archeological: 780-1298 (Originally mis-dated to 831-1349). At least 4 samples depth: 867-1185. As best: 19. No other problems found.


Block 2b is very problematic. It is dated by Bråthen to 1490, and the youngest part is obviously correctly dated, but the older part does not correlate at all to other references at its given position! Instead that older part correlates as if the whole 2b-block should be dated to 1197, i.e the samples in the oldest part are erroneously dated 293 years too late! Samples of two very different ages have been mixed together.
===BrVQ4===
'''Block 4'''. This chronology is mainly based on buildings in the [[Diocese of Skara]], but also some samples from Lindberg in [[Halland]] is included. Some of the Lindberg samples may also be included in [[HallandQ]]. The chronology is published in the supplement 1983.<ref name="Bråthen1983"></ref>


When carefully reading the documentation and constructing the samples positions and lengths these mistakes were revealed: Six samples from Götene and Kungslena churches which are from early 12'th century have been mixed into the chronology at a position 293 years too late. As there is only an average series available only the "clean ends" may be used as reference, i.e  1419-1490 and 904-974 (misdated as 1197-1267). And of those only 939-974 (35 yrs) and 1419-1482 (63 years) has at least 4 samples depth.  
===BrVQ5===
'''Block 5'''. This chronology contains the Lödöse material from "Block 3", but also a lot of other material from an extended region including [[Diocese of Skara]] and Halland (Halmstad). Some of the material from Halland used in this chronology, is also included in [[HallandQU]].  The chronology is published in the supplement 1983.<ref name="Bråthen1983"></ref>


On page 32-33 is a list of 12 samples which are said to be the samples in the average serie "Block2b", but that list is not correct. That is obvious when compared to the number of samples said to be behind each value in the average chronology. The correct list could almost be reconstructed from the complementary list at pp. 90-94 and the years when the number of years are altered. It is than revealed that one sample from Hedared is forgotten in the first list and that one sample from Götene church is confused i the table.
==Downloads==
 
* The five useful "blocks" is available in [http://taxelson.se/dendro/brvq15.rwl digitalized form] ({{WebCite|5ymIx45zD}})  
{| class="wikitable" border=1
* Two weighted chronologies of correct and corrected blocks (based on the book from 1982) are present is [http://taxelson.se/dendro/BraVSQ.dec available]. In ''BVSQgt4'' all parts with less than four samples depth is removed.
|-
*Material related to the analysis of Block 2b and the construction of the BVSQ-means available at http://taxelson.se/dendro/BrathenEk.zip ({{WebCite|5hPagdLcW}}).
!Id !! Bråthen's id !! Description !! use !! Correct dating (used part)
|-
|Ba1 || Bälinge 1 || 1436-1314 || yes || yes
|-
|Ba2 || Bälinge S. remstycke || 1482-1313 || yes || yes
|-
|Ba3 || Bälinge N. remstycke || 1506-1280 || 1490-1280 || yes
|-
|Go1 || Götene 1 || 1418-1213 || yes || 1125-920<ref>At p.102 Bråthen remarks that there are [[Earlywood]] only for the year 1418. According to the missdating this is to be interpreted as summer (june) 1125! He also remarks that Prof. Erik Lundberg, in a paper 1968, dated the church to 12' century. Lundberg was right! (The correct dating (1125) is noted in [http://www.bebyggelseregistret.raa.se/cocoon/bbr/byggnad_formatted_property.html?propertyId=21000003297528&baseObjectId=21000000349543&baseObjectType=historik&rubrik=Historik&menu1=Byggnad&menu2=Historik Bebyggelseregistret])
</ref>
|-
|Go3 || Götene 3 || 1396-1239 || yes || 1103-946
|-
|Go4 || Götene 4 || 1301-1157 || 1301-1197 || 1008-864 (-904)
|-
|Go5 || Götene 5 || 1383-1198<ref>See p.91 (erroneously 1488-1346 in main table)
</ref> || yes || 1090-905
|-
|He1 || Hedared 1 || 1487-1338 || yes || yes
|-
|He3 || Hedared 3<ref>Not in list, but according to p.91, and as the youngest year corresponds with an altering of the annual number of samples.</ref> || 1426-1268 || 1426-1302<ref>It may also possibly continue backwards in all its length. There are several possibilities which sample is the truncated one: It may be He3 or Go4 (young end) or Ku1 (old end).
</ref> || yes
|-
|He4 || Hedared 4 || 1455-1327 || yes || yes
|-
|He5 || Hedared 5  || 1488-1346 || yes || yes
|-
|Ku1 || Kungslena 1 || 1401-1268 || yes || 1108-975<ref>The logs from Kungslena church are cut after 1108 and not after 1401.
</ref>
|-
|Ku2 || Kungslena 2 || 1393-1227 || yes || 1100-934
|}
<!--(Altitude of Hedared: 200 m a.s.l, Götene: 75 m a.s.l)-->
 
===Block 3===
'''Lödöse, archeological''': 780-1298 (Missdated: 831-1349). At least 4 samples depth: 867-1185. As best: 19. No other problems found.


==Notes==
==Notes==
<references/>
<references/>


[[Category:Tree Ring data]]
[[Category:Tree ring data]]

Latest revision as of 18:54, 18 May 2011

BrVQ. In 1982[1] and 1983[2] Alf Bråthen published Quercus Master Chronologies for Western Sweden, mainly the historical province Västergötland, although he to some extend mixed with samples from Halland in the chronologies from 1983. He calls them simply "Block 1", "Block 2", "Block 2b", "Block 3", "Block 4" and "Block 5", but we will instead use the identities BrVQ1, BrVQ2, BrVQ3, BrVQ4, BrVQ5. All of them except "Block 2b"/BrVQ2b are useful chronologies even if "block 3" needs to be redated. The measurements were originally done in 0.1 mm resolution, but the average series are given in 0.01 mm resolution.

1983 he calls Block 2b "superseded", and in fact it contains severe mistakes which is revealed by an analysis, which was done before I become aware of his corrections in the publication 1983.

A disadvantage of the regional references published in the supplement 1983 (BrVQ4 and BrVQ5) are the mixing material also from Halland. It would have been better if the material from Västergötland/Diocese of Skara had been kept separated from the Halland material. Now we do not have that "clean" local Västergötland/Skara references as we might have had otherwise. The local Halland reference, HallandQU, is now partly based on the same samples as "block 4" and "Block 5".

In addition to the five BrVQ1-5 chronologies, also two weighted chronologies compiled of BrVQ1-3 by Torbjörn Axelson. They are not very meaningful but sometimes mentioned in dating reports and therefor in need of documentation. BraVSQ and BVSQgt4. In the later all sequences with less than four samples depth was removed.

BrVQ1

Block 1. Recent: 1615-1975. At least 4 samples depth: 1634-1974, 9 contemporary stems as best. No problems found.

BrVQ2

Block 2. Historical: 1337-1804. At least 4 samples depth: 1380-1779, 16 contemporary stems as best. Bråthen 1983 do not reports any problems.[2]. Known problem:

  • Value for 1650 is missing.

BrVQ2b

Block 2b. Useless. See BrVQ2b for details.

BrVQ3

Block 3. Lödöse, archeological: 780-1298 (Originally mis-dated to 831-1349). At least 4 samples depth: 867-1185. As best: 19. No other problems found.

BrVQ4

Block 4. This chronology is mainly based on buildings in the Diocese of Skara, but also some samples from Lindberg in Halland is included. Some of the Lindberg samples may also be included in HallandQ. The chronology is published in the supplement 1983.[2]

BrVQ5

Block 5. This chronology contains the Lödöse material from "Block 3", but also a lot of other material from an extended region including Diocese of Skara and Halland (Halmstad). Some of the material from Halland used in this chronology, is also included in HallandQU. The chronology is published in the supplement 1983.[2]

Downloads

Notes

  1. Alf Bråthen: Dendrokronologisk serie från västra Sverige 831-1975. Rapport RAÄ 1982:1. ISBN 91-7192-511-2
  2. 2.0 2.1 2.2 2.3 Alf Bråthen: The tree-ring chronology of Western Sweden 753-1720 in: Dendrokronologiska Sällskapet: Meddelanden 6, 1983.