This dissertation presents results from a multi-year interdisciplinary study of the Late Quaternary geomorphic history of northwest Calvert Island, British Columbia, Canada. There is a considerable knowledge gap in the region pertaining to Cordilleran ice cover and extent as well as landscape response to a uniquely stable relative sea-level history. The objective of this study was to reconstruct this regional landscape response to deglaciation including post-LGM ice cover and extent, relative sea-level changes, coastal landform development, and climate and ecological variance. Methods used to inform this reconstruction included airborne lidar, aerial photography interpretation, sedimentary stratigraphy and detailed sedimentology of samples from shovel pits and lake cores, surficial geology and geomorphic mapping, palaeoecological examinations, and the development of a geochronology using radiocarbon and optical dating. To assist with landscape reconstruction, a new method was developed and used to differentiate littoral and aeolian sands in sediment samples that range in age from Mid to Late Holocene by using modern reference samples. The method utilized a standard optical microscope paired with freely available software (ImageJ) to characterize grain shape parameters. The method was tested on nearly 6,000 sand grains from samples of known and hypothesized depositional settings and was able to correctly identify the depositional setting for 76% of the samples. After testing, the method was used to differentiate littoral and aeolian sands in a number of shovel pit, exposure, and core sediment samples to give context to stratigraphic and geomorphic interpretations. A short-lived Late Pleistocene re-advance of Cordilleran ice occurred in the study area, with radiocarbon ages indicating ice advanced to, and then retreated from, the western edge of Calvert Island between 14.2 and 13.8 ka cal BP, respectively. Sedimentological and palaeoecological information that suggests a cold climate and advancing/retreating glacier as well as lidar remote sensing and field-based geomorphic mapping of moraines in the region provide evidence of the re-advance. After ice retreated from the area, a broad suite of geomorphic landforms developed, including flood plains, iv aeolian dunes, beaches, spits, marshes, and tombolos. Coastal reworking was extensive, with progradation rates greater than 1 m a-1 occurring in some locations during the Late Holocene. These data provide the first evidence of a re-advance of the retreating ice sheet margin on the central coast of British Columbia, contribute an important methodology to advance Quaternary reconstructions, and give a unique account of the geomorphic development of a Pacific Northwest coastline that experienced little relative sea-level change over the Late Pleistocene and Holocene. Results help fill a spatial and temporal gap in the landscape history of British Columbia and have implications for climate and sea-level reconstructions, early human migration patterns, and the palaeoenvironment of an understudied area of the Pacific Northwest coast of North America. / Graduate / 0368 / 0372 / 0426 / jeamer7@gmail.com

A basin analysis was conducted at the Conway Flat coast (Marlborough Fault Zone, South Island, New Zealand) to investigate the interaction of regional and local structure in a transpressional plate boundary and its control on basin formation. A multi-tiered approach has been employed involving: (i) detailed analysis of sedimentary deposits; (ii) geomorphic mapping of terraces, fault traces and lineaments; (iii) dating of deposits by 14C and OSL and (iv) the integration of data to form a basin-synthesis in a sequence stratigraphy framework. A complex thrust fault zone (the Hawkswood Thrust Fault Zone), originating at the hinge of the thrust-cored Hawkswood anticline, is interpreted to be a result of west-dipping thrust faults joining at depth with the Hundalee Fault and propagating eastwards. The faults uplift and dissect alluvial fans to form terraces along the Conway Flat coast that provide the necessary relief to form the fan deltas. These terrace/fan surfaces are ~9 km long and ~3 km wide, composite features, with their upper parts representing sub-aerial alluvial fans. These grade into delta plains of Quaternary Gilbert-style fan deltas. Uplift and incision have created excellent 3D views of the underlying Gilbert-style fan delta complexes from topsets to prodelta deposits. Erosive contacts between the Medina, Rafa, Ngaroma and modern Conway fan delta deposits, coupled with changes in terrace elevations allow an understanding of the development of multiple inset terraces along the Conway Flat coast. These terraces are divided into five stages of evolution based on variations in sedimentary facies and geomorphic mapping: Stage I involves the uplift of the Hawkswood Range and subsequent increased sedimentation rate such that alluvial fans prograded to the sea to form the Medina fan delta Terrace. Stage II began with a period of incision, from lowering sea level or changes in the uplift and sedimentation rate and continued with the deposition of the Dawn and Upham fan deltas. Stage III starts with the incision of the Rafa Terrace and deposition of aggradational terraces in the upper reaches. Stage IV initiated by a period of incision followed by deposition of estuarine facies at ~8ka and Stage V began with a period of incision and continues today with the infilling of the incised valley by the modern fan delta of the Conway River and its continued progradation. New dates from within the Gilbert-type fan deltas along the Conway Flat coast are presented, using OSL and 14C dating techniques. Faulting at the Conway Flat coast began ~ 94 ka, based on the development of the Medina Terrace fan delta with uplift rates ~1.38~1.42 m/ka. The interplay of tectonics and sea level fluctuations continued as the ~79 ka Rafa Terrace fan deltas were created, with uplift rates calculated at ~1.39 m/ka. Detailed 14C ages from paleoforest (~8.4-~6.4 ka) in the Ngaroma Terrace and from the mouths of smaller streams have established uplift rates during the Holocene ~1-3 m/ka, depending on sea level.