Geography of Guam
Open-knowledge reference entry
Guam is a U.S. territory in the western Pacific Ocean, at the boundary of the Philippine Sea. It is the southernmost and largest member of the Mariana Islands archipelago, which is itself the northernmost group of islands in Micronesia. The closest political entity is the Commonwealth of the Northern Mariana Islands (CNMI), another U.S. territory. Guam shares maritime boundaries with CNMI to the north and the Federated States of Micronesia to the south. It is located approximately one quarter of the way from the Philippines to Hawaii. Its location and size make it strategically important. It is the only island with both a protected harbor and land for multiple airports between Asia and Hawaii, on an east–west axis, and between Papua New Guinea and Japan, on a north–south axis.
The island is a result of the volcanic activity created by subduction of the Pacific Plate under the Philippine Sea Plate at the nearby Mariana Trench, which runs from the east of Guam to the southwest. Volcanic eruptions established the base of the island in the Eocene, roughly 56 to 33.9 million years ago (mya). The north of Guam is a result of this base being covered with layers of coral reef, turning into limestone, and then being thrust by tectonic activity to create a plateau.
This brief starts where responsible research should: with the source description of “Geography of Guam” as open-knowledge reference entry. Everything that follows is an evidence route, not borrowed authority.
Why this record matters
The subject matters to the general reference register because the source frames it as open-knowledge reference entry. Its deeper value depends on whether names, dates, institutions and citations support that framing.
The citation trail is more important than the brevity of the summary: it shows where individual claims can be examined in context. The source revision retrieved here is dated Jul 14, 2026. The linked authority identifier is Q5535153. Authority coordinates are 13.442, 144.776. None of the 1 selected statements returned an explicit reference.
Overview language is designed for orientation and should not be treated as a substitute for the evidence cited beneath it. The source lead contains qualifying language; that uncertainty should survive quotation, summary and reuse. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.
How to read it
Use the entry as an orientation point, then follow its citations and revision history. Names, dates and institutional relationships should be checked against the original record.
- Subject orientation
- Search vocabulary
- Locating named sources
The closest primary source, responsible institution and strongest cited specialist reference.
Three-step research path
- Establish the record: confirm the title “Geography of Guam”, its source revision and the description used here.
- Expand the search: follow Geography of Guam primary sources, Geography of Guam archive and Geography research across catalogues and specialist indexes.
- Test the account: compare the strongest cited source with the responsible institution’s current record and note any disagreement.
Questions for further research
- Which source most directly establishes the central claim about “Geography of Guam”?
- Which institution is responsible for the underlying evidence?
- Which cited source is closest to the event, object or claim?
Search terms from this dossier
This entry incorporates text from “Geography of Guam” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.