. Maryland geological survey . Fig. 2.—view showing valley truncated by wave erosion, il/2 miles south of point OF ROCKS, CALVERT COUNTY. MARYLAND GEOLOGICAL SURVEY 129 rents of the Talbot sea rapidly built bars and beaches which ponded thewaters behind and transformed them from brackish-water estuaries tofresh-water lagoons. These lagoons were gradually changed into marchesand meadows by the deposition of detritus brought in from the surround-ing region and on this new land surface various kinds of vegetation tookup their abode (Fig. 7). At first the beach sands advanced in the lagoon. Fig. 7
. Maryland geological survey . Fig. 2.—view showing valley truncated by wave erosion, il/2 miles south of point OF ROCKS, CALVERT COUNTY. MARYLAND GEOLOGICAL SURVEY 129 rents of the Talbot sea rapidly built bars and beaches which ponded thewaters behind and transformed them from brackish-water estuaries tofresh-water lagoons. These lagoons were gradually changed into marchesand meadows by the deposition of detritus brought in from the surround-ing region and on this new land surface various kinds of vegetation tookup their abode (Fig. 7). At first the beach sands advanced in the lagoon. Fig. 7.—Diagram showing advancing Talbot shore-line and ponded stream. and filled up completely that portion of the submerged trough which layimmediately beneath them, but later as the lagoon was silted in more andmore with mud derived from the surrounding basin, the advancing beachcame to rest on this lagoon deposit as a foundation and arrived at lengthat the point where the lagoon had been filled up to the level of wave baseor higher. When this place was reached, another process was added tothat of the beach advance. Heretofore the waves and wind had beensimply pushing forward material over the advancing front, but now that9 130 THE PLIOCENE AND PLEISTOCENE DEPOSITS OF MARYLAND the rrnid deposit in the lagoon had actually reached the level of wavework and had transformed the lagoon from a pond to a marsh or meadow,the breakers attacked the upper portion of the lagoon deposit and denudedit down to the level of wave base as rapidly as they could reach it fromunder the superficial ve
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectpaleont, bookyear1901
