DOI: 10.6084/m9.figshare.19575448
title: Tectonic subsidence and uplift within the Canterbury Basin, South Island, New Zealand

description: Supplementary file 1: The following tables show the input data compiled from lithologic, age and paleo water-depth data for all sites in this project. The Clipper-1 well sediment composition and thicknesses are based on detailed descriptions of cuttings in Schiøler et al. (2011) and Hawkes and Mound (1984). The composition, depth and thickness (in meters) of sediments from sites drilled by IODPExpedition 317 (Figure 3) were calculated based on shipboard smear slide and thin section data (Fulthorpe et al. 2011). For our analyses, sediments were classified as clay, silt or sand (clastic sediments) or micrite, bio-silt or bio-sand (biogenic/chemical sediments) following Kominz et al. (2011). This process was aided by the fact that most (90-95%) of the shipboard data included particle size ratios (Expedition Scientists, 2011a-c). Where sediment particle size ratios were not provided, estimates of sand, silt and clay were based on sediment types. In those rare cases, all lithic fragments were assumed to be half sand-sized and half silt-sized. Half of the chlorite grains were assumed to be silt-sized, and the other half clay-sized. For the biogenic sediments, protist tests were placed in appropriate particle sizes (e.g., silt-size for coccolithophores and diatoms and sand-sized for foraminifera and radiolarians). Clay-sized particles were quantified as the sum of clay minerals observed, as well as half of the chlorite present. After applying these assumptions, particle sizes were normalized to 100 percent. Density is the grain density of the unit in grams per cubic centimeter and was estimated based on the composition from the smear slide or thin section data. Ratios of clay (or shale), micrite, sandstone, bio-sand (sand-sized biogenic grains), silt, bio-silt (silt-sized biogenic grains) are provided in parts per one. That is, they sum to 1.00 = 100%. Estimates of the lithologies and thicknesses of the strata beneath the IODP Expedition 317 boreholes were estimated using the sediment lithologies of the Clipper-1 well. Water depths are generally those of the Clipper-1 well. Thicknesses and ages of Neogene strata are modified based on seismic imaging (Figure 5). These data are included in the analysis only to allow for compaction beneath the observed boreholes and are not used for interpretation or conclusions in our manuscript. They are indicated by the shaded data in these tables. The known age of each unit at its top (end of deposition) is provided in Ma. Unknown ages of units are indicated by using zero (0). Numerical ages were obtained by interpolating within the backstripping program. Interpolated ages are included in Data Supplement File 4 (output data). The age at the base of the syn-rift sediments was taken to be 100 Ma. Minimum paleo water depth (Min. wd, also, at the end of deposition of this unit), mean paleo water depth (water depth), and maximum paleo water depth (Max. wd) are provided (in meters). Ages and environments for the Clipper-1 well were from Schiøler et al. (2011) for Eocene and older sediments and from our work (see Data Supplement File 3) for Oligocene and younger strata. Supplementary File 2: POROSITY DATA Dvorak et al. "Tectonic subsidence and uplift within Canterbury Basin, South Island, New Zealand" All porosity data used in this manuscript are provided as well as the intercept (porosity at zero depth = f, in percent), decay constant (c, in meters) and the correlation coeficient (R-squared) for the four porosity vs. depth curves (equation below) that we defined based on silt, clay, sand and biogenic sand-sized samples from the IODP 317 boreholes. ϕ=ϕ_0 ∫1▒e^((-z)⁄c) Porosities are based on Moisture and Density shipboard analyses (Fulthorpe et al. 2011). Lithologies are described in the text and Supplementary Data File 1 (input data). Supplementary File 3: Clipper-1 Well Biostratigraphic Data - Dvorak et al. "Tectonic subsidence and uplift within Canterbury Basin, South Island, New Zealand" Interpretations and comparison with earlier models are provided in the Biostrat Data. Interpretations of ages and sedimentation rates in columns AG-AL are not those used in this manuscript. Raw data on fossil ranges are provided in the Range Chart. Raw data showing fossil distributions are provided on the Distribution Chart. Raw laboratory data are also provided. For further information contact m.crundwell@gns.cri.nz. Supplementary File 4: Supplement Output File5. Dvorak et al. "Tectonic subsidence and uplift within Canterbury Basin, South Island, New Zealand" This file provides the backstripped data from the Clipper-1 well and the site U1351, U1352 and U1353 boreholes. Ages are interpolated using the control input ages in supplement file 1, input data. 'Well-sed' is the tectonic subsidence obtained based only on unloading the decompacted sediments. 'Well-min' is 'well-sed' plus the minimum paleo water depth estimate. 'Well-best' is 'well-sed' plus the average of the high and low ranges of paleo water depth. 'Well-max' is 'well-sed' plus the maximum paleo water depth estimate. 'Well-sstar' is the decompacted sediment thickness of the entire sediment colum at that time. 'Well-obs' is the observed sediment thickness of the column at that time. Only the Clipper-1 well was compared to the theoretical subsidence of stretched continental lithosphere. This data set includes the two curves generated by looking at the difference between theoretical thermal subsidence and the observed subsidence. The first, "∆SLAiry" is the result of titting the "Clipper-SL" tectonic subsidence curve to a thermal cooling plate model "MK∆SL" from 84 to 10 Ma. The second, "DiffminWD" is the missfit to the "Clipper-min" tectonic subsidence result. The numbers above these two columns are the best-fit Mckenzie (1978) stretching factors. The best fit thermal model curves to all tectonic subsidence curves are also provided. Finally we have plotted the backstripping results for the Clipper-1 well as well as tectonic subsidence results for each well in this study.