# All of them are natural geophysical or cryogenic sounds (icequakes, grounding icebergs, volcanic eruptions…

> Most likely: All of them are natural geophysical or cryogenic sounds (icequakes, grounding icebergs, volcanic eruptions and tremor).

Source: https://mysteriesdept.com/mysteries/noaa-ocean-sounds/answers/ANS0D9C7DH635Z3/all-of-them-are-natural-geophysical-or-cryogenic-sounds  
Publisher: Mysteries Department  
Licence: CC BY 4.0 (credit Mysteries Department and link the page)  

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[Questions](https://mysteriesdept.com/questions)[Bloop and NOAA's unexplained ocean sounds](https://mysteriesdept.com/mysteries/noaa-ocean-sounds)[What made the loud unidentified sounds recorded by NOAA's Pacific hydrophones in the 1990s?](https://mysteriesdept.com/mysteries/noaa-ocean-sounds/questions/QST0D9C7CA41BJB/what-made-the-loud-unidentified-sounds-recorded-by-noaas)Answer

Answer · Bloop and NOAA's unexplained ocean sounds

# All of them are natural geophysical or cryogenic sounds (icequakes, grounding icebergs, volcanic eruptions…

All of them are natural geophysical or cryogenic sounds (icequakes, grounding icebergs, volcanic eruptions and tremor).

**Most likely** Answers **1** questionPublished0

## Where it stands

**Most likely** Its tests partly supported it: four pieces of evidence for, one against. It needs two reviews to be accepted.

## What it predicts

- Each sound's bearing points to a region with ice or active volcanoes at the recorded time.
- Each spectrogram falls inside the range of modern labelled recordings of ice or volcanic sources.
- Similar sounds recur in later records from the same directions.

## What would rule it out

- A sound whose recomputed bearing and spectrum fit no known ice or volcanic source, and which recurs with a pattern no ice or volcano follows.

## Evidence 4 for · 1 against

[Antarctic icebergs are a major natural sound source heard at mid and equatorial latitudes, with seasonal…](https://mysteriesdept.com/mysteries/noaa-ocean-sounds/evidence/EVD0D9C7DS01TAX/antarctic-icebergs-are-a-major-natural-sound-source-heard-at)

Established

FOR

[Ice tremor reaches estimated source levels near 245 dB re 1 µPa at 1 m and travels thousands of kilometres.](https://mysteriesdept.com/mysteries/noaa-ocean-sounds/evidence/EVD0D9C7E0T3FGG/ice-tremor-reaches-estimated-source-levels-near-245-db-re-1)

Established

FOR

[NOAA assigns four of the six sounds to ice and one to a volcano; Upsweep remains unresolved.](https://mysteriesdept.com/mysteries/noaa-ocean-sounds/evidence/EVD0D9C7EGE4BDY/noaa-assigns-four-of-the-six-sounds-to-ice-and-one-to-a)

Supported

FOR

[Ross Sea icebergs were recorded as far away as French Polynesia around the same years.](https://mysteriesdept.com/mysteries/noaa-ocean-sounds/evidence/EVD0D9C7E8M6XH4/ross-sea-icebergs-were-recorded-as-far-away-as-french)

Established

FOR

[The original records and bearings have not been published, so the individual attributions cannot be checked…](https://mysteriesdept.com/mysteries/noaa-ocean-sounds/evidence/EVD0D9C7ER81E4N/the-original-records-and-bearings-have-not-been-published-so)

Established

AGAINST

## The questions it answers

[What made the loud unidentified sounds recorded by NOAA's Pacific hydrophones in the 1990s?](https://mysteriesdept.com/mysteries/noaa-ocean-sounds/questions/QST0D9C7CA41BJB/what-made-the-loud-unidentified-sounds-recorded-by-noaas)

Most likelyAll of them are natural geophysical or cryogenic sounds (icequakes, grounding icebergs, volcanic eruptions…

## Cite it

```
Mysteries Department. (2026). All of them are natural geophysical or cryogenic sounds (icequakes, grounding icebergs, volcanic eruptions… [Answer ANS0D9C7DH635Z3]. https://mysteriesdept.com/r/ANS0D9C7DH635Z3
```

Key

**ANS** 0D9C7DH635Z3

Kind

Answer · hypothesis

Origin

Published

Version

1

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