Soru

Passage A
During the late nineteenth century, oceanography relied almost exclusively on mechanical wire sounding to estimate ocean depths. Pioneer expeditions, most notably that of the HMS Challenger (1872–1876), lowered weighted hemp lines and later steel piano wire to measure discrete points along transatlantic traverses. Scientists recorded depths by measuring the length of wire unspooled before bottom impact was detected. Because sounding a single point required stopping the vessel for hours and unspooling thousands of meters of line, data points were separated by dozens or even hundreds of nautical miles.

Interpolating between these sparse data points naturally smoothed out topographical variations. Oceanographers concluded that the seabed consisted primarily of featureless abyssal plains—immense, sediment-covered basins devoid of significant relief. Prominent geological features were assumed to be isolated volcanic islands rising sharply from flat sea floors rather than continuous mountain chains. While wire sounding successfully disproved the long-held myth that the deep ocean was bottomless, its methodological sampling limitations unwittingly fostered a conceptual paradigm of marine topography as fundamentally quiescent and flat.

Passage B
The introduction of acoustic echo sounding in the 1920s transformed marine geophysics by substituting mechanical lines with sound waves. By emitting ultrasonic pulses and recording the precise travel time required for the sound waves to bounce off the seafloor and return to the surface, echo sounders enabled moving vessels to collect continuous profiles of oceanic depth.

When the German Research Vessel Meteor surveyed the South Atlantic between 1925 and 1927, acoustic profiles revealed a startlingly dynamic underwater landscape. Rather than a flat, featureless abyssal plain, the bathymetric data demonstrated that the ocean floor was bisected by an enormous, rugged underwater ridge system. Continuous acoustic data captured steep slopes, sharp peaks, and deep axial rift valleys that had escaped detection during sparse wire-sounding surveys. The data synthesized by Meteor researchers demonstrated that oceanic bathymetry was structurally complex and geologically active.

Subsequent synthesis of cross-passage evidence shows how technological shifts alter scientific models. Where mechanical sounding provided static, localized data points that led researchers to infer vast topographic uniformity, continuous acoustic sounding supplied dense spatial data revealing extensive tectonic structures. Echo sounding did not merely refine previous measurements; it overturned the foundational assumption of abyssal flatness, establishing that ocean basins contain active geological features comparable in scale to continental mountain ranges.

Based on both passages, how does the evidence gathered by acoustic echo sounding (Passage B) most directly challenge the main conclusions drawn from wire sounding data (Passage A)?