[问答题] 简述海洋地质学的定义。

以下采用附属市场模式进行运作的二板市场是（） ["美国NASDAQ","韩国KOSDAQ","新加坡的第二板市场","日本JASDAQ"] Clearances of bridges and overhead cables below Bonneville Dam refer to heights in feet above mean （）. ["lower low water","high water","low water","sea level"] 自由降落艇在收回归位后操作人员应该首先做的工作是（）。 ["挂好吊艇钩收紧吊艇索","解脱吊环存放在艇内顶棚上","解脱吊环固定在艇尾左右吊环座盒内"] M型焦炉炭化室有效容积为（）m3。 ["37.6","38.5","40"] Clearance gauges at bridges indicate （）. ["the height of the tide","depth of water under the bridge","charted vertical clearance at mean low water","distance from the water to low steel of the bridge"] 简述海洋地质学的定义。