AUGUST 30, 1901.] 



SCIENCE. 



327 



western Louisiana through Texas into Mexico, 

 is one of the newest made and least understood 

 of our American geographic provinces. 



In topographic aspect it is apparently an al- 

 most level plain sloping at the rate of about one 

 foot to the mile seaward, but within its area 

 there are slight irregularities or undulations, 

 hitherto unnoticed or at least not described, 

 which are now attracting great attention, owing 

 to their supposed relation to the occurrence 

 beneath them of oil. 



The Louisiana extension of the prairie is gen- 

 erally acknowledged to be a subsiding land as 

 attested by actual bench marks, by the drowned 

 character of the bayous and by the cycles of 

 cypress growth on the swamps. I know of no 

 actual previous observations bearing upon the 

 isostasy of the Texas portion of the prairie, but 

 McGee in a recent article in the National Geo- 

 graphic Magazine assumed that it was also sub- 

 siding. 



I have just made some observations, how- 

 ever, which lead me to believe that west of the 

 Trinity river, at least as far south as the mouth 

 of the Colorado — beyond which we know noth- 

 ing — the plain is rising. 



Between the Trinity and the Colorado all the 

 streams have new-cut channels, characteristic 

 of rising land, while the Brazos is actually cut- 

 ting down through its own alluvium at sea level 

 and for many miles above its mouth. Not only 

 is the coast prairie now undergoing differential 

 movement — subsiding in one part and rising in 

 another — but there is strong evidence that it is 

 being wrinkled and folded, the strata so affected 

 being so recent in age that they cannot be as- 

 signed to any other period of time than Pleisto- 

 cene or recent. These folds are so slight that 

 they could never have been detected had it not 

 been for the discovery of oil on Spindletop Hill, 

 four miles south of Beaumont, by Captain A. 

 F. Lucas, in January last. 



When this gentleman endeavored to point 

 out to me this hill, my trained topographic eye 

 could hardly detect it, for it rises by a gradual 

 slope only ten feet above the sea of prairie plain 

 which surrounds it. I was still more incredu- 

 lous when Captain Lucas insisted that this 

 mound, only two hundred acres in extent, was 

 a dome, and that it had been uplifted by the 



pressure of gas from the great pool of oil now 

 proved to be coincident in extent beneath it. 

 Captain Lucas said that I should be convinced 

 of the uplift if I could see Damon's Mound in 

 Brazoria County. I have just returned from 

 Damon and a second look at Spindletop, and 

 am convinced that if these hills are not recent 

 quaquavefsal uplifts no other hypothesis will 

 explain their existence. 



Damon's Mound is an elliptical oval hill a 

 mile or more in greatest diameter. It rises 

 ninety feet above the surrounding level plain. 

 Its profile is everywhere convex instead of 

 concave, and it is not a hill of erosion or of 

 volcanic material. Furthermore, a bed of lime- 

 stone follows the contour of its "surface, show- 

 ing deformation. The ascent of the plain will 

 not carry the latter to the height of this mound 

 for one hundred miles interiorward. The oil 

 men have insisted on this structure and are 

 spending $200,000 upon Damon's Mound alone, 

 merely upon their belief that its structure is 

 anticlinal. Not only this, but they have seized 

 upon every hill of this character on the coast 

 prairie of western Louisiana and Texas, and 

 are sinking at least 100 wells at an ex- 

 pense of $10,000 a piece to demonstrate their 

 theory. 



Concerning the stratigraphy of the coastal 

 plain, it can only be said that at Galveston it is 

 composed of at least 3,000 feet of unconsolidated 

 land, derived sands and clays, with occasional 

 lignite logs and estuai'ine shells. All this is 

 later than the Eocene Tertiary — the last datum 

 point we have in the Tertiary and Pleistocene 

 stratigraphy of Texas. Of this thickness Harris 

 has shown 2,000 feet to be post Tertiary or not 

 proved as old as Tertiary. Fossils from the 

 Beaumont wells, depth 1,030 feet, have been 

 assigned to the 'Neocene,' but as 'Neocene' 

 means nothing — being merely a word to con- 

 ceal our ignorance of all the later Tertiary 

 strata of the United States — the position of the 

 oil is still uncertain. It is my opinion that the 

 oil is in strata which may as well be called 

 Pleistocene or recent. They are certainly later 

 than any proved Tertiary strata. 



One thing is certain. This oil occurs in un- 

 derground pools, and another thing is probable, 

 that these pools underlie dome-shaped anti- 



