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Subject: buried coastline geol. Подскажите, пож-та, существует ли какой-нибудь принятый термин для buried coastline? Заранее большое спасибо.This conceptual coastal bluff profile is important in that it illustrates the top of the coastal bluff, which coincides with the seaward edge of the coastal terrace, the geologic contact between the lower cliff-forming sediments, and the upper terrace deposits and the contemporary shore platform, which has been created by relatively recent, in geologic terms, relatively recent marine erosion. The contact between the cliff-forming sediments and the upper terrace deposits is important also, in that this geologic contact itself represents an abrasion platform, which formed about 125,000 years ago when sea level was about 25 feet higher than it is today. Obviously, the ***buried coastline*** would be off to the right of this picture; actually, in Solana Beach, it’s about 1,200 feet to the right of this picture along Cedros Boulevard. When sea level dropped some 120,000 years ago, the terrace deposits formed on this old abrasion surface. The relic abrasion surface and the contemporary shore platform have the same geomorphic origins and represent the abraded surface of the sea floor, as marine erosion advances the coastal bluff landward. Recognize also that the transient sand beach resides on top of this bedrock shore platform surface, with a healthyback beach berm at around elevation +12 feet, and throughout Solana Beach and Encinitas, this cliff/platform junction elevation is around –1 foot MSL. Thus, when compared to the healthy backbeach of a decade ago, today we have lost upwards of 13 to 14 feet of a protective barrier that in the past has protected this coastline from marine erosion.
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