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VII. — On the Geology of the Neighbourhood of Lisbon. 



By DANIEL SHARPE, Esq., F.G.S. 



[Read January 9 and 23, 1839.] 



Plates XIV. and XV. 



CONTENTS. 



Preliminary Remarks, p. 107. 



PART I. 



Aqueous Deposits, p. 108. 



Tertiary Formations, p. 108. 

 " 1. Upper Tertiary Sand, p. 108. 

 Mineral contents, p. 109. 



2. Almada Beds, p. 109. 

 Organic remains, p. 112. 

 Comparison with the tertiary beds of the 



South of Spain, p. 113. 



3. Lower Tertiary Conglomerate, p. 113. 

 Secondary Formations, p. 115. 



1. Hippurite Limestone, Tp. \\5. 

 Organic remains, p. 116. 



2. Red Sandstone, p. 117. 

 Mineral contents, p. 119. 

 Organic remains, p. 120. 



3. Espichel Limestone, p. 120. 



Organic remains, p. 121. 



4. Slate-clay and Shale, p. 122. 



5. San Pedro Limestone, p. 122. 

 Organic remains, p. 123. 



6. Older Red Conglomerate, p. 123. 



PART IL 



Igneous Rocks, p. 124. 



Basalt, p. 1 24. 



Granitic Rocks, p. 127. 

 Faults and Dislocations, p. 128. 



Near Cintra, p. 128. 



Between Palmella and Cape Espichel, 

 p. 129. 

 Superficial Detritus, p. 130. 

 Appendix. On the earthquake of Lisbon, 1755, 



p. 130. 

 Postscript, Sept. 1840, p. 132. 



PRELIMINARVr REMARKS. 

 In 1832 I laid before the Geological Society a few remarks on the strata in the 

 neighbourhood of Lisbon ; but having since spent some time in that city, I have been 

 able to extend my observations and to correct the errors into which I had before 

 fallen. During the latter part of my stay, I had the advantage of becoming ac- 

 quainted with the Baron d'Eschwege, the author of a paper upon part of the district, 

 in the eleventh volume of the Memoirs of the Royal Academy of Sciences of 

 Lisbon, to whom I am indebted for much valuable information. 



In the present paper my former remarks are repeated only as far as is necessary 

 to render the rest intelligible, I shall first describe the aqueous formations, fol- 



p2 



