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Details Title: Sed Rocks Description: principles of sedimentology and stratigraphy by Boggs Total Flash Cards: 12 Created: 03/07/2006 21:04:59	To study from this set of flash cards, or to create your own your own study flash cards, register HERE. If you are already a registered user, CLICK HERE.
Cards Term ALLUVIAL FAN Definition 1.DEPOSIT AT EDGE OF MOUNTAIN FRONT (OR GLACIER) WHOSE SURFACE FORMS A SEGMENT OF A CONE THAT RADIATES DOWNSLOPE FROM THE STREAM SOURCE 2. DECREASE IN STREAM GRADIENT AT FOOT OF MOUNTAIN & LOSS OF CONFINING CHANNEL RESULTS IN LOSS OF COMPETENCY OF STREAM, SO SEDIMENT IS DEPOSITED Term DEBRIS FLOWS Definition HIGH DENSITY, HIGH VELOCITY FLOW POORLY SORTED; 1-3 M THICK LOBATE TONGUES EXTENDING FROM SHEETS "OVERSIZE" CLASTS; STRUCTURELESS OR GRADED Term MUD FLOWS Definition "DEBRIS FLOW" THAT LACKS GRAVEL <0.5 M THICK; POORLY SORTED; STRUCTURELESS Term CHANNEL FLOWS Definition TYPICAL BRAIDED STREAM DEPOSITS Term SHEET FLOOD Definition THIN FLOW OF WATER <0.3 M THICK SHEET-LIKE SAND &SILT (LITTLE CLAY) PARALLEL LAMINATIONS; BEDS <0.3 M THICK Term SIEVE DEPOSITS Definition LOBES OF GRAVEL THAT ARE DEPOSITED WHEN WATER INFILTRATES POROUS SURFACE OF FAN WELL-SORTED; 1-3 M THICK; CLASTS > 1 M RARE; STRUCTURELESS; CHIEFLY ON UPPER FAN; LOBATE GEOMETRY Term Rip Currents Definition Term microtidal BACKSHORE Definition Dunes = typical eolian stratification; possibly root traces & burrows Storm beach = same as swash zone Term microtidal FORESHORE Definition 1. Swash zone = parallel laminations dipping <10?seaward (= low angle cross- beds) 2. Sand waves or dunes = trough and tabular cross-beds Term microtidal SHOREFACE Definition current ripples & wave ripples & cross laminations formed from them; minor bioturbation Term microtidal TRANSITION ZONE Definition mud interlaminated with rippled or laminated sand; more bioturbation than shoreface Term Detrital Definition is a geological term used to describe particles of rock derived from pre-existing rock through processes of weathering and erosion. Detrital particles can consist of lithic fragments (particles of recogniseable rock), or of monomineralic fragments (mineral grains). These particles are often transported through sedimentary processes into depositional systems such as riverbeds, lakes or the ocean forming sedimentary successions. Diagenetic processes can transform these sediments into rock through cementation and lithification, forming sedimentary rocks such as sandstone. These rocks can then in turn again be weathered