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Sunday, January 6, 2019

A forgotten upheaval

Among the many amazing stories from India that went into the pages of science is that of Sindri fort. It is hardly mentioned in India anymore but it was of interest to Charles Lyell whose work was significant for Charles Darwin. This fort sank along with a large area around it on 16 January 1819 around 6.45 PM when the region was struck by an earthquake that also caused a tsunami. While this region sank, the northern edges a few kilometers away rose up. It formed a feature that was named as Allah Bund. It apparently became, for a while, a standard textbook example demonstrating a dynamic earth, one that was no longer God's static creation but one where sudden and catastrophic changes could occur. Some years ago, when I learned about the significance of this location in the history of geology and evolutionary thought, I decided that it needed a bit more coverage and began an entry in Wikipedia - Sindri Fort. When referring to geographical entities, Wikipedia articles can also be marked by coordinates (so as to show up on maps) but I had a lot of trouble figuring out where this fort stood, and having never been anywhere near Gujarat, I had set it aside after some fruitless searches across the largely featureless Rann of Kutch as seen on Google Earth. Today, I happened to look up the work of a geologist A.B. Wynne and found that he had mapped the region in 1869 (along with the very meticulous people from the Survey of India). Fortunately, the Memoirs of the Geological Survey have recently been scanned by the Biodiversity Heritage Library and are readily available online. I downloaded the four map pages and stitched them into one large map which I then uploaded the map to Wikimedia Commons (the shared image repository of Wikipedias in various languages) at https://commons.wikimedia.org/wiki/File:Kutch_geology.jpg and then altered the metadata template from one for information to "map" instead - this then allowed the image to be transferred to the MapWarper (an open-source system) installation at https://warper.wmflabs.org/ - finding a few corresponding points on the old map and a geo-referenced base map allowed me to overlay the image atop Google Earth by exporting a kml file of the alignment.
Wynne's 1869 map of the region (stitched)

I then looked up Google Earth to see what lay under the location of the ruins of the Sindri Fort indicated on the old map from 1869 and not very far (within a kilometer) from the marked location, lo and behold, there were faint traces of a structure which would be right where Sindri Fort stood. So here it is for anyone interested. It is quite possible that the location is well-known to locals, but it was still quite thrilling that one could work this out from afar thanks to the accessibility of information. It would not have been possible but for a combination of Wikipedia, the Biodiversity Heritage Library, the Internet Archive, Google Earth, the Warper project, and the numerous people behind all these who are working not just as researchers but as research enablers.


It would seem that this was not visible until the imagery of 2013 became available.

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