Tumor deposits in axillary adipose tissue in patients with breast cancer:Do they matter?

Tumor deposits(TDs)are defined as discrete,irregular clusters of tumor cells lying in the soft tissue adjacent to but separate from the primary tumor,and are usually found in the lymphatic drainage area of the primary tumor.By definition,no residual lymph node structure should be identified in these tumor masses.At present,TDs are mainly reported in colorectal cancer,with a few reports in gastric cancer.There are very few reports on breast cancer(BC).For TDs,current dominant theories suggest that these are the result of lymph node metastasis of the tumor with complete destruction of the lymph nodes by the tumor tissue.Even some pathologists classify a TD as two lymph node metastases for calculation.Some pathologists also believe that TDs belong to the category of disseminated metastasis.Therefore,regardless of the origin,TDs are an indicator of poor prognosis.Moreover,for BC,sentinel lymph node biopsy is generally used at present.Whether radical axillary lymph node dissection should be adopted for BC with TDs in axillary lymph nodes is still inconclusive.The present commentary of this clinical issue has certain guiding significance.It is aimed to increase the awareness of the scientific community towards this under-recognized problem in BC pathology.

Depositional process of hyperpycnal flow deposits:A case study on Lower Cretaceous Sangyuan outcrop in the Luanping Basin,Northeast China

Sedimentary process research is of great significance for understanding the distribution and characteristics of sediments.Through the detailed observation and measurement of the Sangyuan outcrop in Luanping Basin,this paper studies the depositional process of the hyperpycnal flow deposits,and divides their depositional process into three phases,namely,acceleration,erosion and deceleration.In the acceleration phase,hyperpycnal flow begins to enter the basin nearby,and then speeds up gradually.Deposits developed in the acceleration phase are reverse.In addition,the original deposits become unstable and are taken away by hyperpycnal flows under the eroding force.As a result,there are a lot of mixture of red mud pebbles outside the basin and gray mud pebbles within the basin.In the erosion phase,the reverse deposits are eroded and become thinner or even disappear.Therefore,no reverse grading characteristic is found in the proximal major channel that is closer to the source,but it is still preserved in the middle branch channel that is far from the source.After entering the deceleration phase,normally grading deposits appear and cover previous deposits.The final deposits in the basin are special.Some are reverse,and others are normal.They are superimposed with each other under the action of hyperpycnal flow.The analysis of the Sangyuan outcrop demonstrates the sedimentary process and distribution of hyperpycnites,and reasonably explain the sedimentary characteristics of hyperpycnites.It is helpful to the prediction of oil and gas exploration targets in gravity flow deposits.

Effects of soil crust on the collapsing erosion of colluvial deposits with granite residual soil

Collapsing erosion is a unique phenomenon commonly observed on the granite residue hillslopes in the tropical and subtropical regions of southern China,characterized by its abrupt occurrence and significant erosion volumes.However,the impacts of soil crust conditions on the erosion of colluvial deposits with granite residual soils have only been studied to a limited extent.To address this issue,this study investigates the impacts of three soil crust conditions(i.e.,without crust,10-minute crust,and 20-minute crust)on gully morphology,rainfall infiltration,and runoff and sediment yield during slope erosion of colluvial deposits with granite residues(classified as Acrisols)in Yudu County,Ganzhou City,Jiangxi Province,China,using simulated rainfall tests and photographic methods.The results showed that as the strength of the soil crust increased,the capacity of moisture infiltration and the width and depth of the gully as well as the sediment concentration and yield ratio decreased;at the same time,the runoff ratio increased.The sediment yield in the without-crust test was found to be 1.24 and 1.43 times higher than that observed in the 10-minute crust and 20-minute crust tests,respectively.These results indicate that soil crusts can effectively prevent slope erosion and moisture infiltration,while providing valuable insights for the management of soil erosion in natural environments.

A Novel Three-stage Tectonic Model for Mississippi Valleytype Zn-Pb Deposits in Orogenic Fold-and-Thrust Belts

Mississippi Valley-type(MVT) Zn-Pb deposits predominantly form within both orogenic forelands and fold-andthrust belts, yet the mineralization process within the latter tectonic setting remains inadequately understood. This study, through a comprehensive review of MVT deposits across global fold-and-thrust belts, introduces a novel model elucidating the mineralization process in the context of tectonic belt evolution. It is demonstrated that during the stage Ⅰ, regional compression is introduced by early stages of plate convergence, causing the folding and thrusting and creating structural or lithological traps such as evaporite diapirs and unconformity-related carbonate dissolution-collapse structures. Thereafter, in stage Ⅱ, hydrocarbons begin to migrate and accumulate within these traps, where reduced sulfur is generated through thermochemical or bacterial sulfate reduction concurrent with or preceding Zn-Pb mineralization. In the subsequent stage Ⅲ, as plate convergence persists, the regional stress transitions from compression to transpression or extension. Under these conditions, steeply-dipping extensional faults are generated, facilitating the ascent of metalliferous brines into early-formed structural or lithological traps. Precipitation of Zn and Pb sulfides occurs through the mixing of Zn-Pb-transporting fluids with pre-existing reduced sulfur or by interaction with hydrocarbons.

Storm Liquefaction Deposits:A Possibility of Time Reversal in Sedimentary Strata of an Estuarial Coastal Area

In the sedimentary strata dating of estuarial coastal areas,it is often found that there is phenomenon of time-reversal in strata.The seabed sediments could be liquefied under storm waves.A laboratory wave flume experiment demonstrated that storm-induced liquefaction deposits are formed by the oscillations of liquefied sediments.In this paper,the particle size distribution and ^(210)Pb_(ex) specific activity of the sediment samples from the liquefaction disturbed zone and adjacent stable zone of the Yellow River Delta were tested.The stratigraphic divisions based on storm liquefaction deposit sequence can effectively explain the vertical changes in particle size and ^(210)Pb_(ex) specific activity.Due to the differentiation of particles during the storm induced liquefaction,coarse and fine particles regrouped,which could explain the phenomenon of time-reversal in dating data.

Classification and mineralization of global lithium deposits and lithium extraction technologies for exogenetic lithium deposits

A reasonable classification of deposits holds great significance for identifying prospecting targets and deploying exploration. The world ’s keen demand for lithium resources has expedited the discovery of numerous novel lithium resources. Given the presence of varied classification criteria for lithium resources presently, this study further ascertained and classified the lithium resources according to their occurrence modes, obtaining 10 types and 5 subtypes of lithium deposits(resources) based on endogenetic and exogenetic factors. As indicated by surveys of Cenozoic exogenetic lithium deposits in China and abroad,the formation and distribution of the deposits are primarily determined by plate collision zones, their primary material sources are linked to the anatectic magmas in the deep oceanic crust, and they were formed primarily during the Miocene and Late Paleogene. The researchers ascertained that these deposits,especially those of the salt lake, geothermal, and volcanic deposit types, are formed by unique slightly acidic magmas, tend to migrate and accumulate toward low-lying areas, and display supernormal enrichment. However, the material sources of lithium deposits(resources) of the Neopaleozoic clay subtype and the deep brine type are yet to be further identified. Given the various types and complex origins of lithium deposits(resources), which were formed due to the interactions of multiple spheres, it is recommended that the mineralization of exogenetic lithium deposits(resources) be investigated by integrating tectono-geochemistry, paleoatmospheric circulation, and salinology. So far, industrialized lithium extraction is primarily achieved in lithium deposits of the salt lake, clay, and hard rock types. The lithium extraction employs different processes, with lithium extraction from salt lake-type lithium deposits proving the most energy-saving and cost-effective.

Sediment-hosted Pb-Zn Deposits in Southwest Sanjiang Tethys and Kangdian Area on the Western Margin of Yangtze Craton

The western margin of Yangtze Craton is known as a significant sediment-hosted base-metal aggregate cluster,especially for Pb-Zn deposits in China,e.g.Jinding,Daliangzi,Tianbaoshan, Kuangshanchang and Qinlinchang deposits.In comparison with the classic MVT deposits in the world, based on the basic geology of the sediment-hosted Pb-Zn deposits,this paper focuses on temporal-spatial distribution of this deposit to further discuss its large scale mineralization and tectonic evolution history.In the SW Sanjiang Thethys,Jinding deposit is typically thrust fault-controlled and hosted mainly in the sandstones and breccia-bearing sandstones,whereas MVT-type deposits are controlled by lithology and faulting/fracturing with a strong preference for carbonate-hosted rocks.Most importantly,Jinding Pb-Zn deposit differs from the other types of sediment-hosted Pb-Zn deposits in which it was formed in a strongly deformed foreland basin within a continental collision zone.In the Kangdian area,the sediment-hosted Pb-Zn deposits were formed in the extensional basin on the side of the continental orogenic belt along the Yangtze Craton.Compared with classic MVT deposits,the Pb-Zn deposits in the Kangdian area belong to MVT deposits.This paper is significant not only for interpretation of the genesis of sediment-hosted Pb-Zn deposits but also for exploiting large base metal deposits in large sedimentary target areas.

REE and C-O Isotopic Geochemistry of Calcites from the World-class Huize Pb-Zn Deposits,Yunnan,China:Implications for the Ore Genesis

The world-class Huize Pb-Zn deposits of Yunnan province,in southwestern China,located in the center of the Sichuan-Yunnan-Guizhou Pb-Zn polymetallic metallogenic province,has Pb＋Zn reserves of more than 5 million tons at Pb＋Zn grade of higher than 25%and contains abundant associated metals,such as Ag,Ge,Cd,and Ga.The deposits are hosted in the Lower Carboniferous carbonate strata and the Permian Emeishan basalts which distributed in the northern and southwestern parts of the orefield.Calcite is the only gangue mineral in the primary ores of the deposits and can be classified into three types,namely lumpy,patch and vein calcites in accordance with their occurrence.There is not intercalated contact between calcite and ore minerals and among the three types of calcite,indicating that they are the same ore-forming age with different stages and its forming sequence is from lumpy to patch to vein calcites. This paper presents the rare earth element（REE） and C-O isotopic compositions of calcites in the Huize Pb-Zn deposits.From lumpy to patch to vein calcites,REE contents decrease as LREE/ HREE ratios increase.The chondrite-normalized REE patterns of the three types of calcites are characterized by LREE-rich shaped,in which the lumpy calcite shows（La）_N〈（Ce）_N〈（Pr）_N≈（Nd）_N with Eu/Eu~＊〈1,the patch calcite has（La）_N〈（Ce）_N〈（Pr）_N≈（Nd）_N with Eu/Eu~＊〉1,and the vein calcite displays（La）_N〉（Ce）_N〉（Pr）_N〉（Nd）_N with Eu/Eu~＊〉1.The REE geochemistry of the three types of calcite is different from those of the strata of various age and Permian Emeishan basalt exposed in the orefield.Theδ^（13） C_（PDb） andδ^（18）O_（Smow） values of the three types of calcites vary from-3.5‰to-2.1‰and 16.7‰to 18.6‰,respectively,falling within a small field between primary mantle and marine carbonate in theδ^（13）C_（PDb） vsδ^（18）O_（Smow） diagram. Various lines of evidence demonstrate that the three types of calcites in the deposits are produced from the same source with different stages.The ore-forming fluids of the deposits resulted from crustal -mantle mixing processes,in which the mantle-derived fluid components might be formed from degassing of mantle or/and magmatism of the Permian Emeishan basalts,and the crustal fluid was mainly provided by carbonate strata in the orefield.The ore-forming fluids in the deposits were homogenized before mineralization,and the ore-forming environment varied from relatively reducing to oxidizing.

豫西熊耳山蒿坪沟Ag-Au-Pb-Zn多金属矿床闪锌矿矿物学和微量元素组成特征及其成矿启示

蒿坪沟银金铅锌多金属矿床是豫西熊耳山地区重要的铅锌多金属矿床之一,矿体主要赋存在蚀变破碎带和断裂带内,成矿与区内岩浆活动关系密切。目前该矿床的研究集中于同位素地球化学、成矿时代和成矿物质来源等方面,但从矿物角度示踪成矿过程的报道较少。本文以矿石中不同世代闪锌矿为研究对象,开展电子探针和LA-ICP-MS原位主微量元素分析,查明不同世代闪锌矿的矿物学和微量元素组成特征,以反演矿床成矿物理化学条件进而约束矿床成因类型。结果表明,该矿床中闪锌矿主要存在两个世代:第一世代闪锌矿(Sp1)呈黑褐色或浅褐色,常与黄铁矿和黄铜矿共生,相对富集Fe、Mn、Cd、Cu和In;第二世代闪锌矿(Sp2)呈黄褐色或暗褐色,与大量方铅矿共生,裂隙被它形黄铁矿和碳酸盐充填,相对富集Co、Ge、Sn和Pb。闪锌矿中主要富集的元素为Fe、Co和In,其中Fe、Mn、Cd、Co和In等元素基本是以类质同象的形式赋存在闪锌矿的矿物晶格中,而Ag、Sb、Cu和Pb可能是以子矿物或显微包裹体的形式赋存。此外,Zn/Cd、Zn/Fe和Ga/In比值以及Fe温度计指示闪锌矿形成于中低温(沉淀时流体温度为229~259℃)和低硫逸度(lgƒ(S_(2))=-12.0~-10.1)的环境下,由成矿阶段II(Sp1到成矿阶段Ⅲ(Sp2其成矿温度可能发生了显著变化,结合面扫描分析结果,指示闪锌矿从核部到边缘温度逐渐降低。通过与国内外典型铅锌矿床闪锌矿微量元素特征对比,结合本矿床闪锌矿中低的Ga/In和Ge/In比值及Ge含量的特征,指示蒿坪沟银金铅锌多金属矿床成矿过程有岩浆活动的参与。综合认为蒿坪沟银金铅锌多金属矿床可能属于岩浆期后热液蚀变岩型和脉型矿床。

Development and validation of a nomogram for preoperative prediction of tumor deposits in colorectal cancer

BACKGROUND Based on the clinical data of colorectal cancer(CRC)patients who underwent surgery at our institution,a model for predicting the formation of tumor deposits(TDs)in this patient population was established.AIM To establish an effective model for predicting TD formation,thus enabling clinicians to identify CRC patients at high risk for TDs and implement personalized treatment strategies.METHODS CRC patients(n=645)who met the inclusion criteria were randomly divided into training(n=452)and validation(n=193)cohorts using a 7:3 ratio in this retrospective analysis.Least absolute shrinkage and selection operator regression was employed to screen potential risk factors,and multivariable logistic regression analysis was used to identify independent risk factors.Subsequently,a predictive model for TD formation in CRC patients was constructed based on the independent risk factors.The discrimination ability of the model,its consistency with actual results,and its clinical applicability were evaluated using receiveroperating characteristic curves,area under the curve(AUC),calibration curves,and decision curve analysis(DCA).RESULTS Thirty-four(7.5%)patients with TDs were identified in the training cohort based on postoperative pathological specimens.Multivariate logistic regression analysis identified female sex,preoperative intestinal obstruction,left-sided CRC,and lymph node metastasis as independent risk factors for TD formation.The AUCs of the nomogram models constructed using these variables were 0.839 and 0.853 in the training and validation cohorts,respectively.The calibration curve demonstrated good consistency,and the training cohort DCA yielded a threshold probability of 7%-78%.CONCLUSION This study developed and validated a nomogram with good predictive performance for identifying TDs in CRC patients.Our predictive model can assist surgeons in making optimal treatment decisions.

Origin of Ore-Forming Fluids of Mississippi Valley-Type (MVT) Pb-Zn Deposits in Kangdian Area, China

Analyses of fluid\|inclusion leachates from ore deposits show that Na/Br ratios are within the range of 75-358 and Cl/Br 67-394, respectively, and this variation trend coincides with the seawater evaporation trajectory on the basis of the Na/Br and Cl/Br ratios. The average Cl/Br and Na/Br ratios of mineralizing fluids are 185 and 173 respectively, which are very close to the ratios (120 and 233) of the residual evaporated seawater past the point of halite precipitation. It is suggested that the original mineralizing brine was derived from highly evaporated seawater with a high salinity. However, the inclusion fluids have absolute Na values of \{69.9\}-\{2606.2\} mmol kg\+\{-1\} and Cl values of \{106.7\}-\{1995.5\} mmol kg\+\{-1\}. Most of the values are much less than those of seawater: Na, 485 mmol kg\+\{-1\} and Cl, 566 mmol kg\+\{-1\}, respectively; the salinity measured from fluid inclusions of the deposits ranges from \{2.47 wt%\} to \{15.78 wt%\} NaCl equiv. The mineralizing brine has been diluted. The \{δ\{\}\+\{18\}O\} and δD values of ore\|forming fluids vary from \{-8.21‰\} to \{9.51‰\} and from \{-40.3‰\} to \{-94.3‰\}, respectively. The δD values of meteoric water in this region varied from \{-80‰\} to \{-100‰\} during the Jurassic. This evidenced that the ore\|forming fluids are the mixture of seawater and meteoric water. Highly evaporated seawater was responsible for leaching and extracting Pb, Zn and Fe, and mixed with and diluted by descending meteoric water, which resulted in the formation of ores.

Risk factors predict microscopic extranodal tumor deposits in advanced stage Ⅲ colon cancer patients

BACKGROUND Colorectal cancer is a frequent cause of cancer-related mortality in patients with lymph node or distant metastases.Pericolonic tumor deposits(TDs)are considered prognostically distinct from lymph node metastases.AIM To investigate risk factors for extranodal TDs in stage III colon cancer.METHODS This was a retrospective cohort study.We selected 155 individuals diagnosed with stage III colon cancer from the database of the Cancer Registry of the Tri-Service General Hospital.The patients were allocated into the groups with/without N1c.Multivariate Cox regression analysis and Kaplan-Meier method were done.The primary outcomes investigate the association between the covariates and extranodal TDs,and prognostic significance of the covariates regarding the survival.RESULTS There were 136 individuals in the non-N1c group and 19 individuals in the N1c group.Patients with lymphovascular invasion(LVI)had a higher risk of TDs.Overall survival rates of patients with and without LVI were 6.64 years and 8.61 years,respectively(P=0.027).The N1c patients without LVI had higher overall survival than those who with LVI(7.73 years vs 4.42 years,P=0.010).CONCLUSION Patients having stage III colon cancer with LVI have a higher probability of having TDs than those with stage III colon cancer without LVI.Stage III colon cancer patients with TDs and LVI could have poor prognosis and outcome.

Volcanism Pacing Slumping Gravity Flow Deposits during the Late Carboniferous in the Southern Margin of the Junggar Basin,China

Deep-water gravity depositional processes and evolution in arc systems have become topics of intense research focus in recent years.This study discusses the co-evolution of volcanism and deep-water gravity flow deposits at the southern margin of the Junggar Basin,based on petrology,geochronology and geochemical analyses.The results show that a massive collapse of unstable sediments from the slope was triggered by volcanism,resulting in the formation of slumping gravity flows.The occurrence of volcanic beds in the slump deposits confirm that synchronous volcanism likely affected sediment instability,triggering gravity flows.The Th/Yb,Ta/Yb and Th/Ta elemental ratios,U-Pb ages of detrital zircons and paleocurrent directions indicate that the North Tianshan(NTS)island arc represents the provenance of the Qianxia Formation.Moreover,statistical data on the pyroclastic components in the gravity flow deposits reveal an intensity index of volcanism,indicating that volcanism is strongly related to gravity flow deposits,especially in terms of the type and distribution of the deposits.A model for volcanically-triggered deep-water gravity flow deposits is established,in order to provide a more in-depth understanding of the co-evolution of volcanism and gravity flow deposits within the depositional setting of the late Paleozoic NTS oceanic subduction margin in the Junggar Basin.

Rb-Sr and Sm-Nd Isochron Ages of the Dongmozhazhua and Mohailaheng Pb-Zn Ore Deposits in the Yushu area, southern Qinghai and Their Geological Implications

Located on the northeast margin of the Qiangtang terrane between the Jinshajiang suture zone and Bangonghu-Nujiang suture zone,the Dongmozhazhua and Mohailaheng Pb-Zn deposits in the Yushu area of Qinghai Province are representative Pb-Zn deposits of the Pb-Zn-Cu polymetallic mineralization belt in the northern part of the Nujiang-Lancangjiang-Jinshajiang area,which are in the front belt of the Yushu thrust nappe system.The formed environments of these two deposits are different from those of sediment-hosted base metal deposits elsewhere in the world.The authors hold that they were formed during the Indian-Asian continental collision and developed within the fold-thrust belt combined with thrust and strike-slip-related Cenozoic basins in the interior of the collisional zone.Studying on the metallogenic epochs of these two deposits is helpful to the understanding of ore-forming regularity of the regional Pb-Zn-Cu mineralization belt and also to the search for new deposits in this region.The age of the Dongmozhazhua deposit has been determined by the Rb-Sr isochron method for sphalerite residues,whereas the age of the Mohailaheng deposit has been determined by the Rb-Sr isochron method for sphalerite residues and the Sm-Nd isochron method for fluorite.The age of the Dongmozhazhua deposit is 35.0-±0.0 Ma （（87Sr/86Sr）0=0.708807） for sphalerite residues.The age of the Mohailaheng deposit is 32.2±0.4 Ma （（87Sr/86Sr）o=0.708514） for sphalerite residues and 31.8±0.3 Ma （（143Nd/144Nd）o=0.512362） for fluorite with an average of 32.0 Ma.Together with the regional geological setting during mineralization,a possible tectonic model for metallogeny of the Dongmozhazhua and Mohailaheng Pb-Zn deposits has been established.These two ages are close to the ages of the Pb-Zn deposits in the Lanping and Tuotuohe basins,indicating that it is possible that the narrow 1000-kilometer-long belt controlled by a thrust nappe system on the eastern and northern margins of the Tibetan plateau could be a giant Pb-Zn mineralized belt.

Incorporation of perigastric tumor deposits into the TNM staging system for primary gastric cancer

BACKGROUND The current prognostic significance of perigastric tumor deposits(TDs)in gastric cancer(GC)remains unclear.AIM To assess the prognostic value of perigastric TDs and put forward a new TNM staging framework involving TDs for primary GC.METHODS This study retrospectively analyzed the pathological data of 6672 patients with GC who underwent gastrectomy or surgery for GC with other diseases from January 1,2012 to December 31,2017 at the Chinese PLA General Hospital.According to the presence of perigastric TDs or not,the patients were divided into TD-positive and TD-negative groups by using the method of propensity score matching.The differences between TD-positive and TD-negative patients were analyzed using binary logistic regression modeling.The Kaplan-Meier method was used to plot survival curves.Multivariate Cox regression modeling and the log-rank test were used to analyze the data.RESULTS Perigastric TDs were found to be positive in 339(5.09%)of the 6672 patients with GC,among whom 237 were men(69.91%)and 102 were women(30.09%)(2.32:1).The median age was 59 years(range,27 to 78 years).Univariate and multivariate survival analyses indicated that TD-positive GC patients had a poorer prognosis than TD-negative patients(P<0.05).The 1-,3-,and 5-year overall survival rates of GC patients with TDs were 68.3%,19.6%,and 11.2%,respectively,and these were significantly poorer than those without TDs of the same stages.There was significant variation in survival according to TD locations among the GC patients(P<0.05).A new TNM staging framework for GC was formulated according to TD location.When TDs appear in the gastric body,the original stages T1,T2,and T3 are classified as T4a with the new framework,and the original stages T4a and T4b both are classified as T4b.When TDs appear in the lesser curvature,the previous stages N0,N1,N2,and N3 now both are classified as N3.When TDs appear in the greater curvature or the distant tissue,the patient should be categorized as having M1.With the new GC staging scheme including TDs,the survival curves of patients in the lower grade TNM stage with TDs were closer to those of patients in the higher grade TNM stage without TDs.CONCLUSION TDs are a poor prognostic factor for patients with primary GC.The location of TDs is associated with the prognosis of patients with primary GC.Accordingly,we developed a new TNM staging framework involving TDs that is more appropriate for patients with primary GC.

Types,characteristics and geological significance of event deposits of Chang 9 Member of Triassic Yanchang Formation in southwestern Ordos Basin,NW China

Through core observation,thin section identification,and logging and testing data analysis,the types and characteristics of event deposits in the ninth member of Yanchang Formation of Triassic(Chang 9 Member)in southwestern Ordos Basin,China,are examined.There are 4 types and 9 subtypes of event deposits,i.e.earthquake,gravity flow,volcanic and anoxic deposits,in the Chang 9 Member in the study area.Based on the analysis of the characteristics and distribution of such events deposits,it is proposed that the event deposits are generally symbiotic or associated,with intrinsic genetic relations and distribution laws.Five kinds of sedimentary microfacies with relatively developed event deposits are identified,and the genetic model of event deposits is discussed.Seismites are mainly developed in the lake transgression stage when the basin expands episodically,and commonly affected by liquefaction flow,gravity action and brittle shear deformation.Gravity flow,mainly distributed in the high water level period,sandwiched in the fine-grained sediments of prodelta or semi-deep lake,or creates banded or lobate slump turbidite fan.It is relatively developed above the seismites strata.The volcanic event deposits are only seen in the lower part of the Chang 9 Member,showing abrupt contact at the top and bottom,which reflects the volcanic activity at the same time.Anoxic deposits are mostly formed in the late stage of lake transgression to the highstand stage.Very thick organic-rich shales are developed in the highstand stage of Chang 9 Member,and the event deposits in the depositional period of these shales are conducive to potential reservoirs.

Petrogenesis and Physicochemical Conditions of Fertile Porphyry in Non-arc Porphyry Mineralization:A Case from Habo Porphyry Cu-Mo Deposits,SW China

The Habo deposit is a typical porphyry Cu-Mo deposit in the Ailaoshan–Red River metallogenic belt.Ore minerals in the Habo deposit typically occur as veins in the monzonite porphyry.Zircon U-Pb dating suggests that the monzonite porphyry formed at 35.07±0.38 Ma.The monzonite porphyry is characterized by high SiO_(2),Al_(2)O_(3),K_(2)O and Na_(2)O contents,with A/CNK ratios ranging from 0.97 to 1.02.All samples exhibit fractionated REE patterns,characterized by high(La/Yb)N ratios(9.4–13.6,average of 11.2).They show adakite-like geochemical features,high Sr concentrations(627–751 ppm,average of 700 ppm),low Y concentrations(15.13–16.86 ppm,average of 15.81 ppm)and high Sr/Y values(39.5–47.4,average of 44.3).These samples have high initial^(87)Sr/^(86)Sr ratios(0.7074–0.7076)and negativeεNd(t)values(-5.1 to-3.7),whereas the zirconεHf(t)values range from-2.2 to+0.4,suggesting that the monzonite porphyry was derived from the partial melting of a thickened juvenile lower crust.The oxygen fugacity,calculated on the basis of the chemical composition of the amphiboles,shows?NNO values ranging from+1.65 to+2.16(average of 1.94)and lg(fO_(2))ranging from-12.72 to-11.99(average of-12.25),indicating that the monzonite porphyry has high oxygen fugacity.Zircons have high Ce^(4+)/Ce^(3+)ratios(29.29–164.24,average of 84.92),with high?FMQ values ranging from+0.50 to+1.51(average of 0.87)and high lg(fO_(2))values ranging from-14.72 to-12.85(average of-14.07),which also indicates that the oxygen fugacity of the magma was high.The dissolved water content of the Habo monzonite porphyry is 9.5–11.5 wt%,according to the geochemical characteristics,zircon-saturation thermometry(692–794°C)and the mineral phases(amphibole,no plagioclase)in the deep magma chamber.Combined with previous studies,we propose that the high oxygen fugacity and high water content of magma played key roles in controlling the formation of the Habo and other Cu-Mo-Au deposits in the Ailaoshan–Red River metallogenic belt.

Research Progress of the Mineralization of Carbonate-Hosted Pb-Zn Deposits in the Sichuan-Yunnan-Guizhou Pb-Zn Metallogenic Province, Southwest China

The Sichuan-Yunnan-Guizhou （SYG） Pb-Zn metallogenic province in the western Yangtze Block, is a key component of the low-temperature metallogenic domain in South China. In this area, more than 400 Pb-Zn deposits have been discovered, and the total proven reserves are up to 260 million tons with lead and zinc grade reaching 10%, even up to 30%.

A Preliminary Review on the Metallogeny of Pb-Zn Deposits in China

Lead and zinc resources are abundant in China, with the reserves of 100 million tons ranking only second in the world. There are more than 3000 lead-zinc mine areas nationwide. The classification of lead-zinc （Pb-Zn） deposits has been a highly controversial issue. From the standpoint of evaluating the potential of mineral resources, we construct a Pb-Zn deposit predictive type of classification scheme, and propose a Pb-Zn deposit comprehensive classification scheme （including 5 classes and 13 sub-types） that regards mineralization as the primary factor and the ore rock as secondary. According to the temporal and spatial distribution of Pb-Zn deposits, we conclude that a multi-period, multi-cycle orogenic environment is the most favorable for lead-zinc deposit growth, that the Proterozoic is the major eon for the growth of igneous-type deposits, the Paleozoic is an important development era for sedimentary Pb-Zn deposits, and the Mesozoic and Cenozoic are the heyday eras of magmatic type lead-zinc deposits. On this basis, we analyse the relationship between tectonic evolution and Pb-Zn metallogenic, and propose that the key factors determining geological mineralization are the metallogenic epoch of mineralization and tectonic environment, which determine the temporal and spatial distribution.

滇西腾冲大硐厂Pb-Zn矿床成因:来自稀土元素地球化学的证据

腾冲大硐厂Pb-Zn矿床是西南“三江”成矿带腾冲地块东部具有代表性的矽卡岩型矿床之一,其成矿过程可划分为矽卡岩期(早、晚矽卡岩阶段)和石英-硫化物期(早、晚硫化物阶段)。方解石是该矿床中最主要的脉石矿物,其形成与铅锌矿密切相关。本文对主成矿期(石英-硫化物期)不同阶段方解石的REE特征与成矿早期(矽卡岩期)符山石、绿帘石以及大弯山单元花岗岩、大理岩和灰岩的REE特征进行对比研究。结果表明,主成矿期2个阶段方解石REE配分模式均为右倾型,∑REE分别为84.68×10^(-6)~125.58×10^(-6)和35.08×10^(-6)~38.24×10^(-6),LREE/HREE值为1.59~2.04和4.36~5.38,(La/Yb)_(N)值为1.12~1.81和4.01~5.72,(La/Sm)_(N)值为2.62~3.16和5.09~6.38,(Gd/Yb)_(N)值为0.64~0.97和1.22~1.30。2个阶段方解石的Yb/La-Yb/Ca投点位于岩浆成因与热液成因的交界部位,符山石、绿帘石、早硫化物阶段方解石和大理岩的Y/Ho值与大弯山单元花岗岩关系密切,晚硫化物阶段方解石的Y/Ho值介于大弯山单元花岗岩和围岩之间,暗示矿床主成矿期两阶段方解石皆为岩浆热液成因,成矿流体主要来源于岩浆热液,但成矿流体在主成矿期晚硫化物阶段的水岩反应过程中可能遭受了二叠系灰岩地层的强烈混染。从成矿早期到主成矿期δEu值分别为1.25~1.75和0.54~0.78,δCe值为0.85~0.94和0.94~1.05,氧化还原环境的转变可能是导致矿质沉淀的主要原因,后期水岩反应对矿质沉淀也存在少量影响。矿区中矿体离早白垩世花岗斑岩体较近,主要呈层状、似层状产于断裂的蚀变碳酸盐岩(矽卡岩)中,矽卡岩矿物自深向浅具有分带性。综合区域地质特征及矿床控矿因素分析,认为大硐厂Pb-Zn矿床属于矽卡岩型Pb-Zn矿床。