A dataset of the mid-brunhes period at site MD05-2925, Solomon Sea: Surface-subsurface planktonic foraminifera stable C-O isotope and Mg/Ca ratios

Here we present derived thermal-hydrological variations data during the Marine isotope stages (MISs) 10–12 using surface and subsurface dwelling planktonic foraminiferal geochemical proxies of a sedimentary core of MD05-2925 (9.3oS, 151.5oE, water depth 1661 m, core depth 1842–2430 cm), Solomon Sea. Globigerinoides ruber (s.s., white, 250–300 µm) and Pulleniatina obliquiloculata (355–425 µm) tests were hand-picked and cleaned for stable carbon and oxygen isotopes and Mg/Ca analyses. Composite benthic foraminifera tests (>250 µm, Uvigerina spp., and Bulimina spp.) are also hand-picked and cleaned for stable oxygen isotope stratigraphy. In total, 235 and 148 measurements for C-O stable isotopes and Mg/Ca ratios for planktonic foraminifera in 2–5 cm resolution for the period from 352.1 to 462.3 ka are presented in this data report, respectively. Age model is established by tuning composite benthic foraminiferal oxygen isotope to global composite benthic foraminifera oxygen isotope stack LR04. Surface and subsurface temperatures and seawater oxygen isotopes (δ18OW, without ice volume correction) were calculated.


a b s t r a c t
Here we present derived thermal-hydrological variations data during the Marine isotope stages (MISs) 10-12 using surface and subsurface dwelling planktonic foraminiferal geochemical proxies of a sedimentary core of MD05-2925 (9.3 o S, 151.5 o E, water depth 1661 m, core depth 1842-2430 cm), Solomon Sea. Globigerinoides ruber ( s.s. , white, 250-300 μm) and Pulleniatina obliquiloculata (355-425 μm) tests were hand-picked and cleaned for stable carbon and oxygen isotopes and Mg/Ca analyses. Composite benthic foraminifera tests ( > 250 μm, Uvigerina spp. , and Bulimina spp. ) are also hand-picked and cleaned for stable oxygen isotope stratigraphy. In total, 235 and 148 measurements for C-O stable isotopes and Mg/Ca ratios for planktonic foraminifera in 2-5 cm resolution for the period from 352.1 to 462.3 ka are presented in this data report, respectively. Age model is established by tuning composite benthic foraminiferal oxygen isotope to global composite benthic foraminifera oxygen isotope stack LR04.

Value of the Data
• Composite benthic foraminiferal oxygen isotope stratigraphy sets foundation for age correlation across regions. Solomon Sea vertical thermal and hydrological profiles across the MIS 11 provide insight to study Indo Pacific Warm Pool (IPWP) dynamics during the past warm interglacial period. • This dataset is in particular useful for regional paleoceanographic and paleoclimatological studies, however, it would be important for global compilations or physical simulations as well. • Composite benthic foraminiferal oxygen isotope data could be used to revise regional oxygen isotope stratigraphy. Surface and subsurface temperature-oxygen isotopes and their gradients could be used to reconstruct the dynamics in the south marginal of IPWP.

Data Description
The dataset contains four worksheets, including depth, planktonic foraminifera oxygen isotope ( δ 18 O C ), Mg/Ca ratio and inferred temperature, calculated seawater oxygen isotope and benthic foraminifera oxygen isotope data, age control point, and average sedimentation rate.
We adopted Anand et al. [2] Mg/Ca-temperature equation to calculate seawater temperature for the selected two planktonic foraminiferal species.  [2] . The most abundant benthic genus in MD05-2925 is Uvigerina spp. ; however, in several levels, especially during termination periods, we could not find enough Uvigerina spp. tests ( < 2 individuals) for benthic foraminifera oxygen isotope analysis. Previous study from MD05-2925 [4] adapted composite benthic foraminifera oxygen isotope stratigraphy for the past 350-kyr. Here we report the original oxygen isotope records from different species/genus in an excel worksheet. In total, there are four age control points are acquired by tuning to global benthic foraminiferal stack LR04 [5] in the study period and calculated sedimentation rates ranged from 3.1-6.5 cm/kyr.
In this dataset we report depth in sediment core, age (ka), geochemical data ( δ 18 O C , δ 13 C C and Mg/Ca ratios) and climatic parameters derived from geochemical proxies (temperatures and δ 18 O W ) in both worksheets for G. ruber and P. obliquiloculata . Composite benthic foraminifera oxygen without species corrections in depth and age in benthic foraminiferal worksheet. Finally, age control points and average sedimentation rate are reported in respectively worksheet.

Experimental design
We hand-picked well-preserved, unbroken and without clear dark spots benthic and planktonic foraminifera tests. Specific cleaning procedures for stable isotope and Mg/Ca were then conducted for subsamples before geochemical analyses [4] . Off-line data reduction and standard calibrations were also introduced after analyses by using standard bracket method. Planktonic foraminiferal Mg/Ca ratios are then converted to temperature and seawater oxygen isotope values then calculated based on the respective species δ 18 O C and corresponding Mg/Ca temperature values [2 , 3] .

Materials
The marine sediment core, MD05-2925, 2843 cm in length, and recovered during the
For oxygen stable isotope analysis, 7-10 planktonic and 2-4 benthic foraminiferal tests were immersed in methanol, ultrasonicated for 10 s, and then rinsed with deionized water 5 times. Samples were immersed afterward in sodium hypochlorite (NaOCl) for 24-hr, and then analyzed with an isotopic ratio mass spectrometer (IRMS), Micromass IsoPrime, at the National Taiwan Normal University. The long-term 1 σ precision of this instrument is better than ±0.05 ‰ ( N = 701, [4] and data are reported with respect to the Vienna Pee Dee Belemnite (VPDB) standard through the calibration of NBS-19 (National Bureau Standards; δ 18 O = −2.20 ‰ ).

CRediT Author Statement
Li Lo: requested samples and designed this study; Tzu-Ling Chang and Yu-Chu Su: picked planktonic foraminifera, sample preparations and measured Mg/Ca ratios; Chih-Kai Chuang, Chuan-Chou Shen, Horng-Sheng Mii and Li Lo: helped on instrument operations, oxygen stable isotope analyses and all authors contributed manuscript preparation and improvement.

Declaration of Competing Interest
The authors declare that they have no known competing financial interests or personal relationships which have or could be perceived to have influenced the work reported in this article.