Earth and Planetary Sciences ETDs


Sean Connell

Publication Date



The stratigraphic architecture of intracontinental rift basins is defined by a dynamic relationship between depositional belts associated with the basin floor and flanking tributary streams on the piedmont. Spatiotemporal distributions of these deposits are sensitive to basin geometry, subsidence rate, and discharge. Understanding how these depositional belts respond to allogenic forcing is examined using experimental and field approaches. Physical experiments focused on the geomorphic evolution of drainage and the resulting stratigraphic architecture in an asymmetrically subsiding basin based on the form of a simple half graben with four interacting supply points of sediment and water that produced an axial fan and longitudinal channel flanked by transverse fans. Imposition of various combinations of lateral and axial sediment flux showed that the locations and widths of the deposits were controlled by relative sediment discharges and not by the location of the subsidence maximum. Except during the highest of axial sediment discharges in the experiment, the axial drainage was dominated by transverse sources through toe cutting. Footwall fans persisted under conditions of high axial-sediment discharge, aided by topographic inheritance and steeper deposit slopes. The hanging-wall fan responded to changes in sediment discharge more slowly than the footwall. Field comparisons focused on a study of Plio-Pleistocene deposits in the tectonically active Albuquerque Basin of New Mexico. Deposits on the distal hanging-wall ramp onlapped a widespread Miocene erosion surface, burying it by 3.0 Ma. These deposits coarsened after 2.6 Ma, forming a broad sheet of amalgamated channel deposits that prograded into the basin until 1.8 Ma. Axial-river deposition focused near the eastern master-fault system until piedmont deposits prograded away from the basin border after 1.8 Ma. Basin-fill deposition ceased when the axial river began incising shortly after 0.8 Ma. The asynchronous progradation of coarse-grained, margin-sourced detritus may be a consequence of half-graben basin shape that promoted extensive bypass of sediment. Integration of the axial drainage and development of this Plio-Pleistocene sequence likely formed as a result of increased discharge due to late Pliocene and early Pleistocene climatic changes.

Degree Name

Earth and Planetary Sciences

Level of Degree


Department Name

Department of Earth and Planetary Sciences

First Committee Member (Chair)

Geissman, John

Second Committee Member

Crossey, Laura

Third Committee Member

Meyer, Grant

Fourth Committee Member

Paola, Christopher

Project Sponsors

National Science Foundation Saint Anthony Falls Laboratory Industrial Consortium, University of Minnesota National Center for EarthSurface Dynamics




Neogene tectonics, nonmarine stratigraphy, basin analysis, Rio Grande Rift, magnetostratigraphy, geomorphology, experimental stratigraphy, Sedimentary basins

Document Type

Dissertation (83598 kB) (111642 kB) (65218 kB) (166024 kB) (140037 kB) (147228 kB) (142075 kB) (149546 kB) (80367 kB) (3659 kB) (73795 kB) (58566 kB) (58307 kB) (55397 kB) (37434 kB) (2490 kB) (79856 kB) (42004 kB) (128419 kB) (150412 kB) (198815 kB) (121008 kB) (139138 kB) (118427 kB) (148684 kB) (64 kB) (2672 kB) (107405 kB) (217582 kB) (198887 kB) (110230 kB)