How the field library is made
LithoMap is designed to make geology useful without making it sound more certain than the evidence allows. These standards apply to formation profiles, state geology, identification guides, comparisons, and interactive resources.
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Our working principles
Each page should help a reader answer a real question, show the evidence behind the answer, and explain what the page cannot establish.
We prefer government geological surveys, national scientific databases, university or museum collections, peer-reviewed research, and formal stratigraphic references. Secondary sources may help locate a primary record, but they do not replace it when a stronger source is available.
Sources support facts, dates, definitions, and interpretations. LithoMap does not copy source prose or mechanically rearrange it. Guides are synthesized in new language for the specific question a field user is likely to ask.
Geologic boundaries, ages, names, fossil ranges, mineral occurrences, and field identifications can be approximate, disputed, revised, or scale-dependent. We state important limits beside the claim instead of hiding them in a general disclaimer.
A scientific record or mapped unit does not prove that a specimen occurs at a particular point, that land is open, or that collecting is lawful. Visitors must confirm ownership, access, closures, permits, and current rules with the responsible authority.
Scientific pages use public-domain or openly licensed images only after the source record, creator, license, and required attribution are checked. When an image is resized, cropped, or converted for web delivery, the page discloses that modification when the license requires it.
We correct material errors, update source-led facts, and improve explanations as evidence changes. Page dates and source lists help readers judge recency. We do not claim named expert review unless that review actually occurred and can be credited accurately.
Research workflow
Rock and mineral names on this website are preliminary possibilities derived from visible properties and simple tests. Weathering, coatings, mixed grains, alteration, treatments, and manufactured materials can mislead. Valuable, hazardous, or ambiguous samples may require a qualified specialist, microscopy, chemistry, spectroscopy, or X-ray diffraction.
Map layers combine records created at different scales, dates, and levels of detail. A boundary can be generalized or uncertain, GPS can be wrong, and field conditions can change. LithoMap maps are informational and never establish a legal boundary, ownership, permission, safe access, or the presence of a collectible specimen.
If a page appears inaccurate, outdated, unclear, or improperly attributed, email contact@ptwreferrals.com with the page URL, the specific concern, and a supporting source when available. We evaluate the evidence before changing scientific content.
