山东半岛东北部全新统研究新进展

New Advance in the Study on the Holocene Sediments in Northeastern Shandong Peninsula

全新世以来山东半岛东北部沿岸的相对海面（基准面）变化控制了入海河流河谷内全新统的发育，并通过影响进入海岸带碎屑物质的类型与数量，深刻影响了海岸带全新统的发育。全新世早期（１０～６ｋａ Ｂ． Ｐ．）快速的相对海面上升导致河谷溯源堆积，河流输沙中的推移质均堆积于河谷中，仅有悬移质进入海岸带堆积，因而海岸全新统下部均为细粒的海湾、湖、沼泽相沉积。全新世中期（６～４ｋａ Ｂ．Ｐ．）时海面虽已相对稳定，但早期基准面上升导致的河谷堆积作用仍在进行，因而中全新统的粗碎屑海岸沉积均为源于基岩海岸侵蚀的含贝壳砂砾石。从全新世后期（４ｋａ Ｂ．Ｐ．以来）开始有较丰富的河流推移质输沙进入海岸带，但由于不同规模河流对相对海面变化的地貌响应有显著差别，不同河流对海岸全新统发育的影响各不相同。上述结论为精确地解释低序列。

Based on field surveying, drilling, dating, pollen and spore analyzing and mapping, this paper deals with the genetic types and ages of the Holocene sediments in the northeastern Shandong Peninsula. The Holocene relative sea level (base level) changes along the northeastern Shandong Peninsula have controlling the formation of the Holocene in the river valleys into the sea, then controlled the formation of the marine Holocene by affecting the type and amount of the debris into the coastal zone. During the early Holocene (1-6ka.B.P.), the relative sea level's rapid rising resulted in backfilling in river valleys, and the river's bed load deposited in their valleys with only suspended load into the coastal zone, so the lower coastal Holocene consists of fine grained bay, lagoon and marsh deposits. During the middle Holocene (6-4ka.B.P.), the relative sea level changes had reached a high stillstand phase, but the backfilling resulted from the base level's rapid rising in the early Holocene still continued, so the coastal middle Holocene consists of coarse sand and gravel with marine shells and their fragments, which were eroded from the rock coastal compartments. In the late Holcene (4ka.B.P.—present) there are abundant river bed load carried into the coastal zone, but rivers with different size have different geomorphic responses to the same relative sea level change, so different rivers have affected the coastal Holocene formation differently. The above results raise theoretical foundation to interpret the lower and small scale sequences.