Oceans are an accumulation feature and alluvial fan are depositional feature
Explanation:
An alluvial fan is a triangular-shaped deposit that is often referred to as alluvium. Are an example of unconsolidated sedimentary deposits, and thus tend to be larger and more predominant in arid and semi-arid regions.
They are typically found in mountainous regions where there is a rapid change in slope. Various types of fan are a proximal fan, medial fan, and the distal fan.
An oceanic basin is a hydrologically formed and covers about 70% of the earth's surface, they collect sediments that are eroded by the continents known as clastic sediments, as well as precipitous sediments.
As alluvial fans feature is associated with elevated highlands the upliftment is necessary as compared to the oceanic basins there exist mid-oceanic ridges and abyssal hills and plains.