10,323
edits
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Line 90: − − ''Literature on lacustrine deposits.'' <ref name=Twenhofel_1950>Twenhofel, W. H., 1950, Principles of sedimentation: New York, McGraw-Hill, 673 p.</ref> <ref name=Fisk_1952>Fisk, H. N., 1952, Geological investigation of the Atchafalaya Basin and problems of Mississippi River diversion: U.S. Army Corps of Engineers, Mississippi River Commission, Vicksburg, Miss., p. 1-145.</ref> <ref name=Bradley_1964>Bradley, W. H., 1964, Geology of Green River Formation and associated Eocene rocks in southwestern Wyoming and adjacent parts of Colorado and Utah: U. S. Geol. Survey Prof. Paper 496A, 86 p.</ref> <ref name=Vanhouton_1964>van Houton, F. B., 1964, Cyclic lacustrine sedimentation, Upper Triassic Lockatong Formation: in D. F. Merriam, ed., Symposium on cyclic sedimentation: Kansas Geol. Bull. 169, p. 497-531.</ref> <ref name=Colemanandgagliano_1965>Coleman, J. M., and S. M. Gagliano, 1964, Cyclic sedimentation in the Mississippi River deltaic plain: Gulf Coast Assoc. Geol. Socs. Trans., v. 14, p. 67-80.</ref> <ref name=Coleman_1966>Coleman, J. M., 1966, Ecological changes in a massive freshwater clay sequence: Gulf Coast Assoc. Geol. Soc. Trans., v. 16, p. 159-174.</ref> <ref name=Axelson_1967>Axelson, V., 1967, The Laitaure Delta, a study of deltaic morphology and processes: Geog. Ann., Stockholm, v. 49, p. 1-127.</ref> <ref name=Colemanandho_1968>Coleman, J. M., and C. L. Ho, 1968, Early diagenesis and compaction in clays: Proc. Symp. on Abnormal Subsurface Pressures, Louisiana State Univ., Baton Rouge, p. 23-50.</ref> <ref name=Reeves_1968>Reeves, C. C., Jr., 1968, Introduction to paleolimnology: in Developments in sedimentology, v. II: Amsterdam, Elsevier, 228 p.</ref> <ref name=Muller_1971>Muller, G., 1971, Sediments of Lake Constance: Guidebook, 8th Inter. Sedimentology Cong., p. 237-252.</ref> −
→Lacustrine delta-fill deposits
The lower two diagrams in Figure 6 illustrate a typical isopach map of a small lake delta infill and variations in log response through such a deposit. The isopach tends to indicate a wedge of coarse clastic sediments sandwiched between lower freshwater organic lacustrine deposits and overlying swamp and marsh deposits. Most often the logs will document the coarsening-upward sequence of this delta fill. Within the sand body, dip angles are often quite high, reaching 10 to 15°, and result primarily from the foresets of the rapidly prograding lacustrine delta. Often, resistivity kicks are extremely common within such a setting and are responses to lignite, coal, and iron-rich seams which form within these essentially red bed deposits. The sand body itself normally displays a graded base; however, in some areas, generally near breaks in the riverbank, thick, sharp-based sands can often accumulate immediately within the region of the actual crevassing.
The lower two diagrams in Figure 6 illustrate a typical isopach map of a small lake delta infill and variations in log response through such a deposit. The isopach tends to indicate a wedge of coarse clastic sediments sandwiched between lower freshwater organic lacustrine deposits and overlying swamp and marsh deposits. Most often the logs will document the coarsening-upward sequence of this delta fill. Within the sand body, dip angles are often quite high, reaching 10 to 15°, and result primarily from the foresets of the rapidly prograding lacustrine delta. Often, resistivity kicks are extremely common within such a setting and are responses to lignite, coal, and iron-rich seams which form within these essentially red bed deposits. The sand body itself normally displays a graded base; however, in some areas, generally near breaks in the riverbank, thick, sharp-based sands can often accumulate immediately within the region of the actual crevassing.
==See also==
==See also==