Matches in SemOpenAlex for { <https://semopenalex.org/work/W90717809> ?p ?o ?g. }
Showing items 1 to 62 of
62
with 100 items per page.
- W90717809 abstract "The Belmont diabase sheet (BDS) is one of numerous hypabyssal tholeiitic intrusions common to the early Mesozoic rift valleys of the mid-Atlantic states. Petrographic, microprobe and whole rock major and trace element analyses in conjunction with limited field and geophysical evidence indicate that the BDS is a westward dipping, irregular basin-shaped intrusive sheet of high-TiO/sub 2/ quartz-normative type diabase. The bulk of the exposed portion of the BDS is fractionated relative to the chill zone composition. A semi-circular outcrop pattern of relatively high MgO rocks surrounds the main body of the BDS. These high-MgO rocks share a distinctive petrography characterized by large, anhedral OPX grains often mantled by inverted pigeonite and are interpreted as a basal cumulate zone. Drill core samples collected from the western portion of the sheet penetrate 500' of fractionated diabase without intersecting the high-MgO layer or a lower chill margin, however,subhedral grains of inverted pigeonite appear in the lowermost core samples. This suggests that the cumulate layer underlies the sheet of >500' depth on the W side and crops out up-dip to the E, N and S where the sheet margins are turned upward. Mass balance calculations indicate that the exposed high-MgO rocks may be derivedmore » from the chill margin composition by accumulation of 13% OPX + 2% CPX + 5% PLAG (AN52) and the remaining rocks of the BDS are derived through fractional crystallization of varying amounts of CPX, OPX and PLAG. Magmatic features characteristic of similar tholeiitic intrusions such as rhythmic layering and a Mg-olivine layer were not observed. However, examination of the BDS and other hypabyssal intrusions offers insight into the limitations and circumstances under which these features may be developed.« less" @default.
- W90717809 created "2016-06-24" @default.
- W90717809 creator A5010513654 @default.
- W90717809 creator A5013212309 @default.
- W90717809 date "1985-01-01" @default.
- W90717809 modified "2023-09-23" @default.
- W90717809 title "Geochemistry and petrogenesis of the Belmont diabase sheet, northern Culpeper Basin, Virginia" @default.
- W90717809 hasPublicationYear "1985" @default.
- W90717809 type Work @default.
- W90717809 sameAs 90717809 @default.
- W90717809 citedByCount "0" @default.
- W90717809 crossrefType "journal-article" @default.
- W90717809 hasAuthorship W90717809A5010513654 @default.
- W90717809 hasAuthorship W90717809A5013212309 @default.
- W90717809 hasConcept C127313418 @default.
- W90717809 hasConcept C151730666 @default.
- W90717809 hasConcept C161509811 @default.
- W90717809 hasConcept C173347748 @default.
- W90717809 hasConcept C17409809 @default.
- W90717809 hasConcept C44938399 @default.
- W90717809 hasConcept C58097730 @default.
- W90717809 hasConcept C5900021 @default.
- W90717809 hasConcept C59235061 @default.
- W90717809 hasConcept C77928131 @default.
- W90717809 hasConceptScore W90717809C127313418 @default.
- W90717809 hasConceptScore W90717809C151730666 @default.
- W90717809 hasConceptScore W90717809C161509811 @default.
- W90717809 hasConceptScore W90717809C173347748 @default.
- W90717809 hasConceptScore W90717809C17409809 @default.
- W90717809 hasConceptScore W90717809C44938399 @default.
- W90717809 hasConceptScore W90717809C58097730 @default.
- W90717809 hasConceptScore W90717809C5900021 @default.
- W90717809 hasConceptScore W90717809C59235061 @default.
- W90717809 hasConceptScore W90717809C77928131 @default.
- W90717809 hasLocation W907178091 @default.
- W90717809 hasOpenAccess W90717809 @default.
- W90717809 hasPrimaryLocation W907178091 @default.
- W90717809 hasRelatedWork W104752717 @default.
- W90717809 hasRelatedWork W1518565720 @default.
- W90717809 hasRelatedWork W1572635196 @default.
- W90717809 hasRelatedWork W178158234 @default.
- W90717809 hasRelatedWork W2055247334 @default.
- W90717809 hasRelatedWork W2095271054 @default.
- W90717809 hasRelatedWork W2099914459 @default.
- W90717809 hasRelatedWork W2274674309 @default.
- W90717809 hasRelatedWork W2281045429 @default.
- W90717809 hasRelatedWork W2299673976 @default.
- W90717809 hasRelatedWork W2551530228 @default.
- W90717809 hasRelatedWork W2731176898 @default.
- W90717809 hasRelatedWork W2801876511 @default.
- W90717809 hasRelatedWork W2887972661 @default.
- W90717809 hasRelatedWork W2912669319 @default.
- W90717809 hasRelatedWork W2958811358 @default.
- W90717809 hasRelatedWork W3009724231 @default.
- W90717809 hasRelatedWork W3022045906 @default.
- W90717809 hasRelatedWork W347479748 @default.
- W90717809 hasRelatedWork W78691971 @default.
- W90717809 hasVolume "17" @default.
- W90717809 isParatext "false" @default.
- W90717809 isRetracted "false" @default.
- W90717809 magId "90717809" @default.
- W90717809 workType "article" @default.