607 



of little thickness, this again being surmounted bv very thick, coarse 

 blocks of breccia. All the breccia are sloping towards the West and 

 the wiiole arrangement seems to be the normal one, resulting from 

 their being deposited as effusiva of the G. Handjawong. In the fine- 

 grained breccia — an integral and transported component of the 

 "Old andesites" — numerous, small enclosures of tertiary sliale 

 were found. 



In the foregoing we saw then that by far the greater part of the 

 sedimentary Tertiary, east of Buitenzorg, is built up of a veiy fine- 

 grained clay -formal ion, in which volcanic material is all but wanting 

 or completely so. Higher up, however, course clastic banks of vol- 

 canic mateiial found their way to (he sui-face. It appeals, then, that 

 the state of matters is just the reverse of Verbeek and Fennema's 

 hypothesis. They supposed the deep-seated portions of the Tertiary 

 to be "brecciated", the upper portions to be "marly". This paralyses 

 their main argument for the higli antiquity of the "old andesites". 



Let us now summarise our arguments against a high antiquity 

 of these rocks : 



J. In no place in the deepest plications of the Tertiaiy did we 

 encounter disclosures of andesite. 



2. The fact that in many places, close to the andesites, a sedi- 

 mentary formation, free from volcanic material, was found, goes 

 very uiuch against a higher antiquity of andesites than of sediments. 

 For this contact the only explanation could be furnished by an ex- 

 tremely complicated system of shifts — of which there are no 

 indications — if the andesites wei-e oldei* than the sedimentary 

 Tertiary. 



3. The fact that in several places, near the contact, the tertiarj^ 

 clays dip in the direction of the andesite goes very much against 

 a higher antiquity of andesite than of shales. 



4. The silicitication of shales at the G. Pantjak can be explained 

 satisfactorily only when assuming that the andesites are younger 

 than the shales. 



5. The occurrence of clay-enclosures in loose andesite fragments 

 west and east of the G. Paint.iar also points to a recent date of 

 andesite. 



6. The fact that between Tji Djanggel and Tji Handjawar 

 andesite breccia are in some places superposed on shales is best 

 explained by assuming that the andesites are younger than the 

 sediments. 



7. Lastly the discovery of enclosures of shale in breccia of the 

 "Old Andesites" at the G. Handjawong proves unequivocally that 



44* 



