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ANNUAL REPORT SMITHSONIAN INSTITUTION, 1932 



Geologically, the Henbury area consists of Ordovician sediments, 

 mostly sandstones and quartzites, which are known as the Larapin- 

 tine series, the nomenclature being derived from the aboriginal name 

 for the adjacent Finke River. Characteristic Ordovician fossils are 

 found in these beds at Tempe Downs, some 60 miles distant. At 

 Henbury wide alluvial plains are interrupted by ridges and hills 

 which generally consist of the more resistant quartzites. 



FiGDRE 1. — Sketch map of the locality 

 THE CRATERS 



The view of the craters from the plain is decidedly unimpressive 

 (pi. 1, fig, 1), so much so that they could very easily escape the 

 notice of an observer who did not approach quite close to them. The 

 only indication of anything unusual is the presence in one of them of 

 green trees, the tops of which are prominent in a region where, owing 

 to the aridity, green vegetation is extraordinarily scarce. 



The number and size of the craters were found to be much greater 

 than was anticipated. Within an area of half a mile square at least 

 12 probable craters were located (fig. 2), varying in size from the 

 smallest with a diameter of about 10 yards up to the largest of which 

 the longest diameter is about 220 yards from rim to rim. The author 

 believes that a more detailed survey over a wider area will probably 

 lead to other craters being: located. 



