在更高起点上推动井神盐化实现转型、创新、率先发展

借鉴台盐公司发展的成功经验,结合井神股份公司发展实际,对井神盐化实现转型、创新、率先发展进行探究与思考。

Composition and Origin of Ferromanganese Crusts from Equatorial Western Pacific Seamounts

In the equatorial western Pacific, iron-manganese oxyhydroxide crusts(Fe-Mn crusts) and nodules form on basaltic seamounts and on the top of drowned carbonate platform guyots that have been swept free of pelagic sediments. To date, the Fe-Mn crusts have been considered to be almost exclusively of abiotic origin. However, it has recently been suggested that these crusts may be a result of biomineralization. Although the Fe-Mn crust textures in the equatorial western Pacific are similar to those constructed by bacteria and algae, and biomarkers also document the existence of bacteria and algae dispersed within the Fe-Mn crusts, the precipitation, accumulation and distribution of elements, such as Fe, Mn, Ni and Co in Fe-Mn crusts are not controlled by microbial activity. Bacteria and algae are only physically incorporated into the crusts when dead plankton settle on the ocean floor and are trapped on the crust surface. Geochemical evidence suggests a hydrogenous origin of Fe-Mn crusts in the equatorial western Pacific, thus verifying a process for Fe-Mn crusts that involves the precipitation of colloidal phases from seawater followed by extensive scavenging of dissolved trace metals into the mineral phase during crust formation.

The importance of non-carbonate mineral weathering as a soil formation mechanism within a karst weathering profile in the SPECTRA Critical Zone Observatory, Guizhou Province,China

Soil degradation, including rocky desertification,of the karst regions in China is severe. Karst landscapes are especially sensitive to soil degradation as carbonate rocks are nutrient-poor and easily eroded. Understanding the balance between soil formation and soil erosion is critical for long-term soil sustainability, yet little is known about the initial soil forming processes on karst terrain. Herein we examine the initial weathering processes of several types of carbonate bedrock containing varying amounts of non-carbonate minerals in the SPECTRA Critical Zone Observatory, Guizhou Province, Southwest China. We compared the weathering mechanisms of the bedrock to the mass transfer of mineral nutrients in a soil profile developed on these rocks and found that soil formation and nutrient contents are strongly dependent upon the weathering of interbedded layers of more silicate-rich bedrock(marls). Atmospheric inputs from dust were also detected.

The main phosphorous sources in the Changjiang estuary

Analysis using historical data on the phosphate sources in Changjiang （Yangtze River） estuary show that phosphate was supplied equally from the east, south, west and north of the estuary. These sources include the Changjiang River, the Taiwan Warm Current （TWC）, a cyclone-type eddy, and the 32°N Upwelling, supplying different phosphates in different times, ways and intensities. The magnitude of their supplying phosphate concentration was related with the size in the order of the Changjiang River 〈 the TWC 〈 the 32°N Upwelling 〈 the cyclone-type eddy, and the duration of the supplying was： the Changjiang River 〉 the TWC 〉 the cyclone-type eddy 〉 the 32°N Upwelling. The four sources supplied a great deal of phosphate so that the phosphate concentration in the estuary was kept above 0.2 pmol/L in previous years, satisfying the phytoplankton growth. The horizontal and vertical distribution of the phosphate concentration showed that near shallow marine areas at 122°E/31°N, the TWC in low nutrient concentration became an upwelling through sea bottom and brought up nutrients from sea bottom to marine surface. In addition, horizontal distribution of phosphate concentration was consistent with that of algae： Rhizosolenia robusta, Rhizosolenia calcaravis and Skeletonema, which showed that no matter during high water or low water of Changjiang River, these species brought by the TWC became predominant species. Therefore, the authors believe that the TWC flowed from south to north along the coast and played a role in deflecting the Changjiang River flow from the southern side.

Nutrient Structure of the Taiwan Warm Current and Estimation of Vertical Nutrient Fluxes in Upwelling Areas in the East China Sea in Summer

Based on field data for nutrients collected on the continental shelf of the East China Sea(ECS) during summer 2006, the structure and variations of nutrients in every water mass related to the Taiwan Warm Current(TWC) were analyzed. The supplementary effect of nutrient of upwelling on harmful algal blooms(HABs) in the ECS was also estimated, based on upwelling data. Then the maintenance contribution of nutrient of upwelling to HABs was assessed. The results showed that N/P ratio is fairly low in both surface and deep layers of the TWC, which possibly controls nutrient structure of the HABs-frequently-occuring areas. In upwelling areas, the rate of phosphate(PO4-P) uptake exceeds that of nitrate(NO3-N) of the TWC. The TWC may relieve PO4-P limitation during the process of HABs. Furthermore, upwelling plays an important role in providing nutrients to HABs. After estimating nutrient fluxes(NO3-N, PO4-P, Si O3-Si) in the upwelling areas along a typical section(S07), the results showed that the nutrient uptake rate is the greatest at 10-20 m below euphotic zone, sustaining the ongoing presence of HABs. The uptake rate of PO4-P is the highest among dissolved inorganic nutrients. Therefore, upwelling is most likely the main source of PO4-P supply to HABs.

Mega-shoaling in carbonate platform of the Middle Triassic Leikoupo Formation,Sichuan Basin, Southwest China

Shoaling is a common type of sedimentation in the evolution of carbonate platform,and commonly has poor continuity.This paper presents a newly discovered and rare type of shoaling,i.e.,mega-shoaling in nearly basin scale,which is developed in the Middle Triassic Leikoupo Formation of the Sichuan Basin,southwest China.During the Leikoupo time,the studied Sichuan Basin experienced hot and dry climate conditions and developed a carbonate platform within a restricted epicontinental sea.In B sub-layer of the Lei-1-1 sub-member of the Leikoupo Formation a series of grainstones of shoal facies accumulated throughout almost the entire basin,thereby generating features associated with basin-scale mega-shoaling.By detailed core examination and microscopic observation of thin sections,it is shown that the lithology of this set of grainstones is dominated by doloarenite(calcarenite)followed by oolitic dolomite(limestone).In addition,it contains three types of sedimentary sequences characterized by upward-coarsening and upward-shallowing as the followings:restricted lagoon to platform interior beach;restricted lagoon to platform interior beach and to platform flat;and tidal flat to peritidal beach.Subsequently,a multicyclic stratigraphic division and correlation revealed that this set of grainstones can be well traced and compared horizontally,and is generally isochronous.In addition,a template for logging facies,established based on core calibrations and logging data,was employed to analyze the 235 wells in the basin.The results demonstrate the shoal grainstones to be 10–40 m thick with a15×104km2continuous distribution area.These findings indicate that the carbonate platform developed mega-shoals within a short period of time.The genesis of such a mega-shoaling was investigated by focusing on various shoaling conditions,such as paleo-tectonics,paleo-geomorphology,paleo-climate,sea-level changes,and palaeo-hydrodynamics.A specific combination of independent geological factors creates beneficial geomorphologic conditions for the mega-shoaling including a quiescent paleo-tectonic environment,relatively flat paleo-geomorphology and evaporites filling up and leveling off.In addition,a stably settling carbonate platform underwent sea-level fluctuations through swift transgressions and protracted regressions,which is not only conducive to continuous,multicyclic and superimposed vertical development of grain beaches but also beneficial for the horizontal migration,coalescence and superimposition of individual grain beaches.As a consequence,large-scale and continuously-distributed grain beach sedimentation emerges and mega-shoals develop.

Distinct sedimentary environments and their influences on carbonate reservoir evolution of the Lianglitag Formation in the Tarim Basin,Northwest China

The Upper Ordovician Lianglitag Formation carbonate rocks are important oil and gas reservoirs in the Tarim Basin, Northwest China, with obviously distinct reservoir properties among different oilfields. As a case area of the above carbonate reser- voirs correlation, Tahe and Tazhong oilfields are chosen for the study through an integrated analysis of biostratigraphic isoch- ronous framework, cores, thin sections, logs, and strontium isotopes. The research shows that the two areas were respectively attributed to different carbonate platforms during the Lianglitag Formation depositional phase. For the Lianglitag Formation, five fourth-order sequences may be divided in Tazhong, whereas only four fourth-order sequences are preserved in Tahe that correspond to the lower ones observed in Tazhong. The Lianglitag Formation carbonate platform in Tahe was characterized by ramp and/or weak rimmed types, with low depositional rates （37 ktm/a）, higher whole-rock clastic contents, and higher 878r/86Sr isotope ratios of carbonate matrix, showing relatively deep-water environment and evident terrigenous input for car- bonate deposition. However, a strongly rimmed carbonate platform was developed in Tazhong, with high depositional rates of 250 p.m/a and less whole-rock clastic contents, indicating a high-energy depositional environment. Because of the sedimentary environment differences mentioned above, less high-energy facies but relatively intense syndepositional （early diagenetic） sea-water cementation of carbonates were developed in Tahe, and ubiquitous high-energy reef and shoal facies, with a frequent exposure to subaerial, and weak syndepositional sea-water cementation of carbonates in Tazhong. Therefore, fewer primary pores occurred in the Lianglitag Formation carbonate rocks of Tahe, whereas more primary pores were preserved in the same lithostratigraphic unit of the Tazhong （No. 1 fault zone）. Available high-energy reef-shoal facies and early diagenesis, with more primary pores preserved, provided a key material basis for the Lianglitag Formation carbonate reservoirs that largely oc- curred in Tazhong.

Paleo-redox conditions across the Permian-Triassic boundary in shallow carbonate platform of the Nanpanjiang Basin, South China

Ocean anoxia has been widely implicated in the Permian-Triassic extinction. However, the duration and distribution of the ocean anoxia remains controversial. In this study, the detailed redox changes across the Permian-Triassic boundary （PTB） in the shallow platform interior at Great Bank of Guizhou （GBG） has been reconstructed based on the high-resolution microfossil composition and multiple paleo-redox proxies. The shallow platform is characterized by low sulfur （total sulfur （TS） and pyrite sulfur （Spy）） concentrations, low Spy/TOC ratios, and low DOP values before the mass extinction, representing oxic conditions well. Following the mass extinction, the shift of multiple geochemical proxies, including high Spy/TOC ratios and DOP values, indicates dysoxic-anoxic conditions in shallow ocean. Furthermore, we reconstruct the transition of the redox conditions of Nanpanjiang Basin： the intense volcanic eruptions, which release huge COz and SO2 before the mass extinction, provoke the temperature rising and the collapse of terrestrial ecosystem. As a result, the increased weathering influx causes the carbon iso- topic negative excursion and the expansion of the ocean oxygen minimum zone （OMZ）. When the OMZ expanded into the photic zone, the episodic H2S release events enhance the pyrite burial at Dajiang section. Thus, intense volcanic eruptions, temperature increase, and oceanic hypoxia together lead to the PTB extinction. Recent studies show high temperature might be the key mechanism of the PTB extinction. In addition, this study confirms that the microbialites were formed in the dysoxic- anoxic shallow water.

干劲冲天 信心百倍——全国省市统计工作保定现场会议胜利闭幕

全国省市统计工作保定现场会议在6月26、27日大会发言后,本着政治挂帅,以虚带实,大会发言与现场参观相桔合的精神,从28日起,全体代表首先参观了以河北省统计局为主,并由国家统计局及北京、上海、山西、四川等省市统计局参加举办的改革统计工作展览会,接着又组成了20个参观团分赴河北省各市县并深入到工厂、工地、学校。