266 C. SCHUCHERT MORRISON AND TENDAGURU FORMATIONS 



pS^o break in sedimentation. 

 Marine T. smeel sandstones, 65 feet. 



Kimmeridgian J Middle dinosaur limy-sandy clay, 50 feet. 



Dinosaurs, Morrison-like. Best skele- 

 I tons here. 



Exact age not yet C Marine Nerinea sandstones, 80 feet, 

 establislied 1 Lower dinosaur sandy clay. 65 feet. 



Upper 

 Jurassic 



Ancient granite and gneiss. Possibly Pre 

 Cambrian in age. 



The Tendaguru series of brackish- to fresh-water shales and shallow- 

 water marine sandstones, together a little over 400 feet thick, overlaps 

 an old gneiss-granite foundation, possibly of Precambian age; all are 

 fully described by Janensch and Hennig in Parts I and II of the German 

 publication. The series is exposed in southern German East Africa in an 

 east and west direction for at least 27 kilometers and north and south for 

 over 100 kilometers. The deposits were laid down between hills and 

 islands of granite. At the base the Tendaguru series is marked by a great 

 unconformity, and on it lies the Makonde formation, and all are to be seen 

 on the high plateaus and in the many deep ravines cutting through them. 

 The three marine zones, together 130 feet thick, are hard, coarse-grained, 

 or even conglomeratic (arkosic), cross-bedded sandstones, with the fore- 

 setting toward the east and northeast, and this feature is in harmony 

 with the general dip, which is in the same direction. The dinosaur zones 

 consist in the main of greenish shales, though certain beds are brick-red 

 in color. The latter color appears to be due to secondary causes, as weath- 

 ering or the percolating of aerial ground waters. In places the dinosaur 

 shales become sandy and are then also cross-bedded, rippled, and have 

 some intraformational shale pieces. Nowhere do the authors mention the 

 presence of sun-cracking. The Makonde variegated red and white muddy 

 sandstones are unfossiliferous, 617 feet in thickness, and are said by 

 Hennig to lie unbroken on the Tendaguru series. Beyond the Tendaguru 

 region the Makonde formation becomes abundantly fossiliferous and the 

 fossils correlate the sandstones with the Urgonian and Aptian, or, in other 

 terms, with the Lower Cretaceous. It would therefore seem that the 

 Makonde is also an overlapping formation and toward the southwest. 

 This feature indicates to the present writer that there is in all probability 

 a break in deposition between it and the Tendaguru series, at least in the 

 Tendaguru area. Unconformably over the Makonde series are the very 

 young Mikindani beds of fluviatile sands and conglomerates (Schotter). 



