grainstone

grainstone

[′grān‚stōn]
(petrology)
A mud-free (micrite-free) limestone.
References in periodicals archive ?
The Kaugatuma Formation traces were made in crinoid grainstone with marl interlayers, those of the Kuressaare Formation in clayey limestone containing fine fossil debris.
Arwa (Kimmeridgian to Tithonian) Fm is composed of argillaceous limestone, deep-water lime mudstone, and locally minor packstone, wackestone, grainstone, and black shale.
SAMPLE 1: DOLOMITIZED OOID GRAINSTONE WITH ISOPACHOUS DOLOMITE CEMENT
The Ninase Member contains fragments of brachiopods and crinoids, and also some tabulate corals (favositids) in the layers of marlstone intercalating with grainstone.
There are scattered bioclastic packstone and grainstone horizons which commonly show fining upward (Wong, 2002); these represent deposition during brief storm events.
A mound in Lawrence County consists chiefly of packstone and grainstone dominated by eclnirnoderrni ossicles amid fragments of fenestrate bryozoarns.
2:00 POROSITY LOSS, FLUID FLOW, AND MASS TRANSFER IN OOID GRAINSTONE RESERVOIRS OF THE SMACKOVER FORMATION, MISSISSIPPI
Carbonates accumulated largely in situ, with micritic wackestones in shallow-water areas, skeletal, oncoid--and stromatoporoid-bearing grainstone facies in mid-ramp settings and muddy, nodular, brachiopod-dominated packstones with minor grainstone beds in areas below normal wave base to the north.
1 Facies Facies Name Subfacies Code JA JA1 Benthic foraminifera Nummulites /Orbitolites bioclast pelloidal bioclast pelloidal packstone packstone JA2 Pelloidal benthic -- foraminifera packstone to grainstone JB JB1 Nummulites wackestone Nummulites packstone to packstone to wackestone Peloid Nummulites packstone Nummulites bioclast pelloidal packstone JC JC1 Planktonic foraminiferal Nummulites/ Discocyclina/ Nummulites/ Discocyclina Operculina wackestone pelloidal wackestone to packstone to packstone Nummulites/ Assilina packstone JC2 Operculina/(smaW) -- Nummulites pelloidal packstone 0.
The classification of Dunham, 1962 divides limestone on the basis of texture into grainstone, packstone, mudstone, wackestone and boundstone.
Most of the formation is composed of skeletal wackestone-packstone and oolitic grainstone.