Sequence Stratigraphy of the Lane Island Creek Shales and the Farley Limestone in Northeastern Kansas and Geologic Factors Affecting the Quality of Limestone Aggregates

008002002000PDFResearch PaperK-TRAN: KU-97-1Limestone aggregatesAggregate testsDurability testsAggregate durabilityClay contentFarley LimestoneKansasLithologic compositionKansasKansas. Dept. of TransportationGoldstein, R.H.Franseen, E.K.McKirahan, J.University of KansasKansas. Dept. of TransportationNTL-HIGHWAY/ROAD TRANSPORTATION-MaterialsNTL-HIGHWAY/ROAD TRANSPORTATION-Pavement Management and PerformanceNTL-HIGHWAY/ROAD TRANSPORTATION-Soils and GeologyUS Transportation CollectionProcedures should be implemented for rapidly evaluating durability of limestone aggregate to prevent use of substandard material in highway construction and to assure availability of highly durable aggregate. The objective of this study is to evaluate lithologic (rock type) variables that control durability of limestone aggregate. The Farley Limestone (Pennsylvanian, Missourian) is one of many limestone units quarried in Kansas for production of highly durable, Class 1 aggregate. By understanding the lithologic factors that control durability of aggregate from the Farley, an analog for other limestone units can be developed. The Farley Limestone was described from 17 localities to define associations of rock types (lithofacies) and to establish correlations to aggregate durability. Data on lithofacies characteristics, spar (coarse calcite or dolomite) percentage, spar size, and insoluble residue percentage exhibit no correlations to durability factor or expansion percentage. Data on total percentage of clay-rich rock, clay distribution, and mineralogy of insoluble residues are correlated to durability and expansion percentage. Limestones containing low percentages of diffuse or disseminated clay are more likely to produce aggregates of high durability. Aggregates containing multiple clay minerals exhibit reduced durability. Smectite, even in small quantities, negatively impacts durability, whereas illite apparently has little impact on durability. If changes in clay content deleterious to aggregate quality can be identified during lateral production of a ledge, then quarrying can be halted or can proceed in another direction while physical tests are run. Such a procedure could prevent use of substandard concrete in highway construction projects. Aggregate-producing phylloid-algal limestones of the lower Farley Limestone thicken into the local depositional lows. However, fine quartz-, feldspar-, and clay-rich sediments (siliciclastics) also seem to be deposited preferentially in paleotopographic lows. Thus, local paleotopographic low areas most distal from sources of siliciclastics can be predicted as the prime area for location of durable aggregate. Due to large file size, this document has been divided into a series of PDF files, accessed from a HTML front page