METEORITE CRATERS — SPENCER 



321 



Argentine Survey, and excavations were made in the hoyo called 

 " Rubin de Cells " (also called " Pozo del Cielo "). 



This is circular with a diameter of 56 meters and a depth of 5 

 meters. Pits dug in the rim and in the center of the depression 

 showed disturbed beds of sandy loess mixed with " white volcanic 

 ashes " and " transparent glass in angular, curved, and striated 

 pieces." There are no volcanic rocks in the surrounding panipa, and 

 the Andean volcanoes are 500 miles away. This transparent glass, 

 if examined, would most probably prove to be silica glass. Small 

 fragments of rusted meteoric iron were found in one of the pits near 

 the rim of the hoyo. A piece of typical iron shale (very similar to 

 that from Henbury) from this excavation was presented to the Brit- 

 ish Museum by Dr. Antenor Alvarez in 1927, but unfortunately none 

 of the glass was sent. Dr. Nagera concludes that the hoyas were not 

 formed by the fall of the masses of meteoric iron, but that they were 

 made by man. There seems, however, little doubt that they are 

 really meteorite craters. They are easily accessible and close to the 

 railway, and should certainly be further investigated. There are 

 other suggestive features worthy of investigation in this district. 

 Many small lakes and pozos are scattered around ; and in particular 

 a chain of small lakes extends southward from the spot where the 

 large masses of meteoric iron have been found for a distance of nearly 

 100 miles into the province of Santa Fe. 



SUMMARY OF CHARACTERS OF METEORITE CRATERS 



The following tabulation of the dimensions of the described craters 

 shows that there is a very wide variation in the ratio of width to 

 depth. This ratio must be rapidly affected by denudation, and 

 perhaps gives some indication of the relative age of the craters. 

 This ratio will also depend on the type of rock, as shown in the two 

 mine craters of La Boisselle and Hill 60. 



Ratio of 



width to 



depth 



Texas 



Ashanti 



Siberia 



Campo del Cielo 



Estonia 



Do 



Do 



Henhiiry 



Do 



Do 



Wabar 



Arizona.. 



Hill 60, Ypres 



La Boisselle, Somme 



29.4 

 26.4 

 12.5 

 11.4 

 11.0 

 9.9 

 6.0 

 10.0 

 9.6 

 6.0 

 8.0 

 6.8 

 6.1 

 3.8 



